JP2011053723A - Optical waveguide and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing an optical waveguide, which produces a core part (optical path) which has a high optical transmission performance, a large degree of freedom in designing a pattern form, and a high dimensional accuracy with a simple method, and to provide an optical waveguide manufactured by the method and to provide an optical waveguide structure equipped with the optical waveguide. <P>SOLUTION: The method of manufacturing the optical waveguide 90 includes: a process to obtain a first layer for a clad layer which is not completely solidified or hardened; a process to obtain a second layer for core layer which is not completely solidified or hardened and of which the refractive index varies by radiation of an active radiation ray or additional heating, and to laminate the second layer on the first layer to obtain a laminated body; and a process to generate a difference in the refractive indices between irradiated regions and non-irradiated regions by the active radiation ray in the second layer by selectively radiating the active radiation ray on the laminated body or additionally heating the laminated body, thus defining either one of two regions as a core part 94 and the other region as a clad part 95. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an optical waveguide and a method for manufacturing the same.

  In recent years, optical branching couplers (optical couplers), optical multiplexers / demultiplexers, and the like have been developed as optical components in the field of optical communications, and optical waveguide devices used for these are promising. As this optical waveguide type element (hereinafter also simply referred to as “optical waveguide”), there are polymer optical waveguides that are easy to manufacture (patterning) and are versatile, in addition to conventional quartz optical waveguides. (For example, refer to Patent Document 1).

  This optical waveguide is generally formed by curing a polymer for a cladding layer to form a lower cladding layer (cladding portion), and then curing a polymer for a core portion to form a core portion. The upper cladding layer (cladding portion) is formed by curing the polymer for the cladding layer so as to cover it.

However, the optical waveguide manufactured by such a method has the following problems. 1. High adhesion between the clad part and the core part cannot be obtained, and high optical transmission performance cannot be obtained.
2. The optical waveguide formation process is complicated, and the degree of freedom in designing and selecting the pattern shape of the core portion is narrow.
3. The core pattern shape accuracy and dimensional accuracy are poor.
4). When combined with a wiring pattern, the degree of freedom in designing the wiring pattern is narrow.

JP 2002-173532 A

  An object of the present invention is to provide an optical waveguide manufacturing method capable of forming a core part (optical path) with high optical transmission performance, a high degree of freedom in pattern shape design, and high dimensional accuracy by a simple method, and An object of the present invention is to provide an optical waveguide manufactured by this manufacturing method.

Such an object is achieved by the present inventions (1) to (45) below.
(1) An optical waveguide manufacturing method comprising: a core layer including a core portion; a cladding portion having a lower refractive index than the core portion; and a cladding layer provided in contact with at least one surface of the core layer. There,
Supplying a cladding layer forming material to form a liquid film, and obtaining a first layer in a state where the liquid film does not completely solidify or cure;
On the first layer, a core layer forming material whose refractive index is changed by irradiation with actinic radiation or by further heating is supplied to form a liquid film, and the liquid film is completely solidified or cured. A second step of obtaining a second layer in an unachieved state and forming a laminate;
By selectively irradiating the laminate with the active radiation or further heating, a refractive index difference is generated between the active radiation irradiated region and the non-irradiated region in the second layer. Thus, there is provided a method for manufacturing an optical waveguide, comprising: a third step in which one of the irradiated region and the non-irradiated region is the core portion and the other is the cladding portion.

(2) The core layer forming material includes a polymer, a monomer that is compatible with the polymer and has a refractive index different from the polymer, a first substance that is activated by irradiation with the active radiation, A second substance capable of initiating a monomer reaction, the second substance having an activation temperature changed by the action of the activated first substance,
In the third step, the first substance is activated in the irradiation region of the second layer by irradiating the active material with the active radiation, and the second substance Change the activation temperature of
Next, by applying heat treatment to the stacked body, the lower one of the second substance or the second substance whose activation temperature is changed is activated, and the second substance is activated. Reacting the monomer either in the irradiated region of the layer or in the non-irradiated region of the actinic radiation to produce a refractive index difference between the irradiated region and the unirradiated region; The method for manufacturing an optical waveguide according to (1), wherein any one of the unirradiated regions is the core portion and the other is the cladding portion.

(3) In the third step, as the reaction of the monomer proceeds in either the irradiated region or the unirradiated region of the second layer, the unreacted monomer gathers from the other region. The manufacturing method of the optical waveguide as described in said (2).

(4) The first substance includes a compound that generates a cation and a weakly coordinating anion upon irradiation with the active radiation, and the second substance is produced by the action of the weakly coordinating anion. The method for producing an optical waveguide according to the above (2) or (3), wherein the activation temperature varies.

(5) The activation temperature of the second substance is lowered by the action of the activated first substance, and irradiation with the actinic radiation is caused by heating at a temperature higher than the temperature of the heat treatment. The method for producing an optical waveguide according to any one of (2) to (4), wherein the optical waveguide is activated without any problems.

(6) The method for manufacturing an optical waveguide according to (5), wherein the second substance includes a compound represented by the following formula Ia.
(E (R) ₃ ) ₂ Pd (Q) ₂ ... (Ia)
[Wherein E (R) ₃ represents a neutral electron donor ligand of Group 15; E represents an element selected from Group 15 of the periodic table; and R represents a hydrogen atom (or One of its isotopes) or a moiety containing a hydrocarbon group, Q represents an anionic ligand selected from carboxylate, thiocarboxylate and dithiocarboxylate. ]

(7) The method for producing an optical waveguide according to (5) or (6), wherein the second substance includes a compound represented by the following formula Ib.
[(E (R) ₃ ) _a Pd (Q) (LB) _b ] _p [WCA] _r (Ib)
[Wherein E (R) ₃ represents a neutral electron donor ligand of Group 15; E represents an element selected from Group 15 of the periodic table; and R represents a hydrogen atom (or One of its isotopes) or a moiety containing a hydrocarbon group, Q represents an anionic ligand selected from carboxylate, thiocarboxylate and dithiocarboxylate, LB represents a Lewis base, WCA Represents a weakly coordinating anion, a represents an integer of 1 to 3, b represents an integer of 0 to 2, the sum of a and b is 1 to 3, p and r are This represents the number that balances the charge between the palladium cation and the weakly coordinated anion. ]

(8) The method for manufacturing an optical waveguide according to (7), wherein p and r are each selected from an integer of 1 or 2.

(9) The method according to any one of (2) to (8), further including a step of performing heat treatment on the stacked body at a second temperature higher than the temperature of the heat treatment after the third step. The manufacturing method of the optical waveguide of description.

(10) After the step of subjecting the laminate to a heat treatment at the second temperature, the step of subjecting the laminate to a heat treatment at a third temperature higher than the second temperature. The manufacturing method of the optical waveguide as described in said (9) which has.

(11) The method for manufacturing an optical waveguide according to (10), wherein the third temperature is 20 ° C. or more higher than the second temperature.

(12) The method for manufacturing an optical waveguide according to any one of (2) to (11), wherein the monomer includes a crosslinkable monomer.

(13) The method for producing an optical waveguide according to any one of (2) to (12), wherein the monomer is mainly a norbornene-based monomer.

(14) The method for producing an optical waveguide according to (12), wherein the monomer is mainly a norbornene-based monomer and contains dimethylbis (norbornenemethoxy) silane as the crosslinkable monomer.

(15) The polymer has a leaving group capable of leaving at least a part of the molecular structure from the main chain by the action of the activated first substance,
In the third step, by selectively irradiating the actinic radiation to the laminate, the leaving group of the polymer is released in the irradiation region of the second layer (2 The manufacturing method of the optical waveguide in any one of (14) thru | or (14).

(16) The first substance includes a compound that generates a cation and a weakly coordinating anion upon irradiation with the actinic radiation, and the leaving group is separated from the acid by the action of the cation. The manufacturing method of the optical waveguide as described in said (15) which is a property group.

(17) The material for forming the core layer includes a substance activated by irradiation with the actinic radiation, a main chain, and the action of the substance branched and activated from the main chain, so that at least a part of the molecular structure is And a polymer having a leaving group capable of leaving the main chain,
In the third step, by irradiating the laminated body with the actinic radiation, the substance is activated in the irradiation region of the second layer, and the leaving group of the polymer is released. Then, by causing a refractive index difference between the irradiated region and the non-irradiated region, either the irradiated region or the non-irradiated region is the core portion, and the other is the cladding portion. The manufacturing method of the optical waveguide as described in (2).

(18) The method for manufacturing an optical waveguide according to (17), further including a step of performing heat treatment on the stacked body after the third step.

(19) The substance includes a compound that generates a cation and a weakly coordinating anion upon irradiation with the actinic radiation, and the leaving group is an acid leaving group that is released by the action of the cation. A method for producing an optical waveguide according to the above (17) or (18).

(20) The light guide according to the above (16) or (19), wherein the acid leaving group has at least one of an —O— structure, an —Si—aryl structure, and an —O—Si— structure. A method for manufacturing a waveguide.

(21) The method for producing an optical waveguide according to any one of (15) to (20), wherein the leaving group causes a decrease in the refractive index of the polymer due to the leaving.

(22) The method for producing an optical waveguide according to (21), wherein the leaving group is at least one of a -Si-diphenyl structure and a -O-Si-diphenyl structure.

(23) The method for producing an optical waveguide according to any one of (2) to (22), wherein the polymer is mainly a norbornene-based polymer.

(24) The method for producing an optical waveguide according to (23), wherein the norbornene-based polymer is an addition polymer.

(25) The method for producing an optical waveguide according to any one of (1) to (24), wherein the active radiation has a peak wavelength in a range of 200 to 450 nm.

(26) The method for producing an optical waveguide according to any one of (1) to (25), wherein the irradiation amount of the active radiation is 0.1 to 9 J / cm ² .

(27) The optical waveguide manufacturing method according to any one of (1) to (26), wherein the active radiation is applied to the stacked body through a mask.

(28) The method for manufacturing an optical waveguide according to any one of (1) to (27), wherein the second layer further includes an antioxidant.

(29) The method for manufacturing an optical waveguide according to any one of (1) to (28), wherein the second layer further includes a sensitizer.

(30) The cladding layer forming material contains a polymer,
The method for producing an optical waveguide according to any one of (1) to (29), wherein the polymer is mainly a norbornene-based polymer.

(31) The method for producing an optical waveguide according to (30), wherein the norbornene-based polymer is an addition polymer.

(32) The method for producing an optical waveguide according to (30) or (31), wherein the norbornene-based polymer includes a repeating unit of alkyl norbornene.

(33) The method for producing an optical waveguide according to any one of (30) to (32), wherein the norbornene-based polymer includes a norbornene repeating unit having a substituent containing a polymerizable group.

(34) The norbornene repeating unit having a substituent containing a polymerizable group is a norbornene repeating unit having a substituent containing an epoxy group, a norbornene repeating unit having a substituent containing a (meth) acryl group, and The method for producing an optical waveguide according to the above (33), which is at least one of repeating units of norbornene having a substituent containing an alkoxysilyl group.

(35) The method for producing an optical waveguide according to (33) or (34), wherein at least a part of the norbornene-based polymer is crosslinked at a polymerizable group.

(36) The method for producing an optical waveguide according to any one of (30) to (32), wherein the norbornene-based polymer includes a norbornene repeating unit having a substituent containing an aryl group.

(37) The method for producing an optical waveguide according to (36), wherein at least a part of the norbornene-based polymer is crosslinked through a crosslinking agent.

(38) The method for manufacturing an optical waveguide according to any one of (1) to (37), wherein the viscosity (normal temperature) of the core layer forming material is higher than the viscosity (normal temperature) of the cladding layer forming material.

(39) The method for manufacturing an optical waveguide according to any one of (1) to (38), further including a step of drying the laminated body prior to the third step.

(40) Prior to the third step, a second clad layer forming material is supplied on the second layer to form a liquid film, and the liquid film does not completely solidify or cure. The method for manufacturing an optical waveguide according to any one of (1) to (39), further including a step of obtaining a third layer in a state to obtain the laminated body.

(41) An optical waveguide manufactured by the method for manufacturing an optical waveguide according to any one of (1) to (40).

(42) The optical waveguide according to (41), wherein an average thickness of the cladding layer is 0.1 to 1.5 times an average thickness of the core layer.

(43) An optical waveguide structure comprising the optical waveguide according to (41) or (42) and a conductor layer provided on at least one surface side of the optical waveguide.

(44) The optical waveguide structure according to (43), wherein an average thickness of the conductor layer is 10 to 90% of an average thickness of the optical waveguide.

(45) The optical waveguide structure according to (43) or (44), wherein the conductor layer is formed by at least one of a dry plating method, a wet plating method, and a bonding of a conductive sheet material. body.

  According to the present invention, high adhesion can be obtained between the core layer (core portion) and the clad layer (cladding portion). Thereby, peeling at the interface of each part is prevented, and an optical waveguide having high optical transmission performance can be obtained.

  Further, according to the present invention, the core portion can be patterned by a simple method of irradiation with active radiation, and the core portion having a wide degree of freedom in designing the pattern shape of the core portion and high dimensional accuracy can be obtained. .

  In addition, when the core layer is made of a desired material, when the stress is applied to the optical waveguide or deformation occurs, particularly even when repeatedly curved and deformed, delamination between the core portion and the cladding portion, Defects such as the occurrence of microcracks in the core are unlikely to occur, and as a result, the optical transmission performance of the optical waveguide is maintained and the durability is excellent.

  Furthermore, when the core part is composed of a norbornene polymer as a main material, the effect of being particularly strong against the deformation and being difficult to cause defects is high, and the difference in refractive index between the core part and the cladding part is made larger. In addition, an optical waveguide having excellent heat resistance and higher performance and durability can be obtained.

  In addition, when the conductor layer is formed, wiring to the element is easy, and wiring suitable for the element is possible regardless of the type of the element (terminal installation location), and the versatility is high. Moreover, such a wiring circuit pattern using a conductor layer has a wide degree of freedom in design (for example, a degree of freedom in selection of a terminal installation location).

  Such an optical waveguide or optical waveguide structure of the present invention has a wide range of optical circuit (optical waveguide pattern) and electrical circuit design, good yield, high optical transmission performance, reliability and durability. Excellent in versatility. Therefore, the optical waveguide and the optical waveguide structure of the present invention can be used for various electronic parts, electronic devices, and the like.

1 is a perspective view (partially cut away) showing an embodiment of an optical waveguide structure of the present invention. It is sectional drawing which shows typically the process example of the 1st manufacturing method of the optical waveguide structure of this invention. It is sectional drawing which shows typically the process example of the 1st manufacturing method of the optical waveguide structure of this invention. It is sectional drawing which shows typically the process example of the 1st manufacturing method of the optical waveguide structure of this invention. It is sectional drawing which shows typically the process example of the 1st manufacturing method of the optical waveguide structure of this invention. It is sectional drawing which shows typically the process example of the 1st manufacturing method of the optical waveguide structure of this invention. It is sectional drawing which shows typically the process example of the 1st manufacturing method of the optical waveguide structure of this invention. It is a chart which shows the change of the total optical loss accompanying the change of the length of a core part.

  Hereinafter, the manufacturing method of an optical waveguide of the present invention, an optical waveguide, and an optical waveguide structure are explained in detail based on a suitable embodiment shown in an accompanying drawing.

  FIG. 1 is a perspective view (partially cut away) showing an embodiment of an optical waveguide structure of the present invention.

In the following description, the upper side in FIG. 1 is “upper” or “upper”, and the lower side is “lower” or “lower” (the same applies to the following drawings).
Each figure is exaggerated in the thickness direction of the layer (the vertical direction in each figure).

  The optical waveguide structure 9 shown in FIG. 1 has an optical waveguide 90 and conductor layers 901 and 902 provided on the upper surface and the lower surface, respectively, and these layers are bonded.

  The constituent materials of the conductor layers 901 and 902 are, for example, various metal materials such as copper, copper-based alloy, aluminum, and aluminum-based alloy, indium tin oxide (ITO), and fluorine-containing indium tin oxide (FTO). And various oxide materials.

  The average thicknesses of the conductor layers 901 and 902 are each preferably about 10 to 90% of the average thickness of the optical waveguide 90, and more preferably about 20 to 80%. Specifically, the average thickness of the conductor layers 901 and 902 is not particularly limited, but is usually preferably about 3 to 100 μm and more preferably about 5 to 70 μm. Thereby, it is possible to make the conductor layers 901 and 902 excellent in conductivity while preventing the flexibility of the optical waveguide structure 9 from being lowered.

  Moreover, in the structure shown in FIG. 1, both the conductor layers 901 and 902 have comprised flat form (sheet form). In this case, after processing into a predetermined pattern of the conductor layers 901 and 902, an optical element (light emitting element, light receiving element, etc.) is mounted at a desired location, thereby manufacturing a composite device including an optical circuit and an electric circuit. can do.

  The conductor layers 901 and 902 may be previously patterned (wiring). Moreover, you may abbreviate | omit either one of the conductor layers 901 and 902 as needed.

  Further, between the conductor layers 901 and 902 and the optical waveguide 90, one layer or two or more layers for any purpose (for example, the purpose of improving adhesion) may be provided.

  The optical waveguide 90 is formed by laminating a clad layer (lower clad layer) 91, a core layer 93, and a clad layer (upper clad layer) 92 in this order from the lower side in FIG. A pattern core portion 94 and a clad portion 95 adjacent to the core portion (waveguide channel) 94 are formed.

  The difference in refractive index between the core portion 94 and the clad portion 95 is not particularly limited, but is preferably about 0.3 to 5.5%, and particularly preferably about 0.8 to 2.2%. If the difference in refractive index is less than the lower limit, the effect of transmitting light may be reduced, and even if the upper limit is exceeded, no further increase in light transmission efficiency can be expected.

The refractive index difference is expressed by the following equation, where A is the refractive index of the core portion 94 and B is the refractive index of the cladding portion 95.
Refractive index difference (%) = | A / B-1 | × 100

  In the configuration shown in FIG. 1, the core portion 94 is formed in a straight line shape in a plan view, but may be curved or branched in the middle, and the shape is arbitrary. In addition, if the manufacturing method of the optical waveguide structure 9 which is mentioned later is used, the core part 94 of a complicated and arbitrary shape can be formed easily and with a sufficient dimensional accuracy.

  The core section 94 has a quadrangular shape such as a square shape or a rectangular shape (rectangular shape).

The width and height of the core portion 94 are not particularly limited, but are preferably about 1 to 200 μm, more preferably about 5 to 100 μm, and still more preferably about 10 to 60 μm.

  The core portion 94 is made of a material having a higher refractive index than that of the cladding portion 95, and is also made of a material having a higher refractive index than the cladding layers 91 and 92.

  The clad layers 91 and 92 constitute the clad portions located at the lower part and the upper part of the core part 94, respectively. With such a configuration, the core portion 94 functions as a light guide path whose outer periphery is surrounded by the cladding portion.

  The average thickness of the clad layers 91 and 92 is preferably about 0.1 to 1.5 times the average thickness of the core layer 93, more preferably about 0.3 to 1.25 times, Specifically, the average thickness of the clad layers 91 and 92 is not particularly limited, but is usually preferably about 1 to 200 μm, more preferably about 5 to 100 μm, and about 10 to 60 μm. More preferably. Thereby, the function as a clad layer is suitably exhibited while preventing the optical waveguide 90 from becoming unnecessarily large (pressure film).

  The constituent materials of the clad layer 91, the clad portion 95, and the clad layer 92 may be the same (same type) or different from each other, but they have the same or similar refractive index. Is preferred. Details of the constituent materials of the cladding layers 91 and 92 and the core layer 93 will be described later.

  The optical waveguide structure 9 of the present invention is slightly different depending on the optical characteristics of the material of the core portion 94 and is not particularly limited. For example, the optical waveguide structure 9 is preferably used in data communication using light in the wavelength region of about 600 to 1550 nm. The

Next, an example of a method for manufacturing the optical waveguide structure 9 will be described.
<First manufacturing method>
First, the 1st manufacturing method of the optical waveguide structure 9 is demonstrated.

  2-7 is sectional drawing which shows typically the process example of the 1st manufacturing method of the optical waveguide structure of this invention, respectively.

[1A] First, a clad layer forming material (first varnish) including a clad material is applied to the support substrate 1000 to form a liquid film, and this liquid film does not completely solidify or harden (unfinished) A first layer 1110 in a solidified or uncured state is obtained (see FIG. 2).

  When the liquid film is formed by a coating method, examples thereof include a doctor blade method, a spin coating method, a dipping method, a table coating method, a spray method, an applicator method, a curtain coating method, a die coating method, and the like. It is not done.

  As the support substrate 1000, for example, a silicon substrate, a silicon dioxide substrate, a glass substrate, a quartz substrate, a polyethylene terephthalate (PET) film, or the like is used.

  The average thickness of the first layer 1110 is not particularly limited, but is preferably about 5 to 200 μm, more preferably about 10 to 100 μm, and still more preferably about 15 to 65 μm.

[2A] Next, a core layer forming material (second varnish) is applied onto the first layer 1110 using the same method as described above to form a liquid film. Thus, the second layer 1120 in a state of not solidifying or curing (unsolidified or uncured) is obtained (see FIG. 3).

  The average thickness of the second layer 1120 is not particularly limited, but is preferably about 5 to 200 μm, more preferably about 15 to 125 μm, and still more preferably about 25 to 100 μm.

  The core layer forming material is a material whose refractive index changes by irradiation with active radiation or by further heating.

  The core layer forming material of this embodiment is a photo-induced heat-developable material (PITDM) composed of a polymer 915 and an additive 920 (in this embodiment, including at least a monomer, a promoter and a catalyst precursor). In the polymer 915, a monomer reaction occurs upon irradiation with actinic radiation and heating.

  In the resulting second layer 1120, any polymer (matrix) 915 is distributed substantially uniformly and randomly, and the additive 920 is substantially uniformly and randomly distributed within the polymer 915. Are distributed. Thereby, the additive 920 is substantially uniformly and arbitrarily dispersed in the second layer 1120.

  The polymer 915 has sufficiently high transparency (colorless and transparent) and is compatible with the monomer described later, and the monomer can react (polymerization reaction or crosslinking reaction) as described later. Even after the monomers are polymerized, those having sufficient transparency are preferably used.

  Here, “having compatibility” means that the monomer is at least mixed and does not cause phase separation with the polymer 915 in the core layer forming material or the second layer 1120.

  Examples of such polymers 915 include cyclic olefin resins such as norbornene resins and benzocyclobutene resins, acrylic resins, methacrylic resins, polycarbonates, polystyrenes, epoxy resins, polyamides, polyimides, polybenzoxazoles, and the like. Among them, one or a combination of two or more thereof (polymer alloy, polymer blend (mixture), copolymer, etc.) can be used.

  Among these, those mainly composed of norbornene resins (norbornene polymers) are preferable. By using a norbornene-based polymer as the polymer 915, the core layer 93 having excellent optical transmission performance and heat resistance can be obtained.

  Moreover, since norbornene-type polymer has high hydrophobicity, the core layer 93 which cannot produce the dimensional change by water absorption etc. easily can be obtained.

  The norbornene polymer may be either one having a single repeating unit (homopolymer) or one having two or more norbornene repeating units (copolymer).

  Examples of such norbornene-based polymers include (1) addition (co) polymers of norbornene monomers obtained by addition (co) polymerization of norbornene monomers, and (2) norbornene monomers and ethylene or α-olefins. (3) addition polymers such as addition copolymers with norbornene-type monomers and non-conjugated dienes, and other monomers as required, (4) ring opening of norbornene-type monomers ( A (co) polymer, and a resin obtained by hydrogenating the (co) polymer if necessary, (5) a ring-opening copolymer of a norbornene-type monomer and ethylene or α-olefins, and ( (Co) polymer hydrogenated resin, (6) ring-opening copolymer of norbornene type monomer and non-conjugated diene or other monomer, and (co) polymerization if necessary And a ring-opening polymer such as a polymer obtained by hydrogenating the body. Examples of these polymers include random copolymers, block copolymers, and alternating copolymers.

  These norbornene-based polymers include, for example, ring-opening metathesis polymerization (ROMP), combination of ROMP and hydrogenation reaction, polymerization by radical or cation, polymerization using a cationic palladium polymerization initiator, and other polymerization initiators ( For example, it can be obtained by any known polymerization method such as polymerization using a polymerization initiator of nickel or another transition metal).

  Among these, as the norbornene-based polymer, those having at least one repeating unit represented by the following chemical formula 1 (Structural Formula B), that is, an addition (co) polymer is preferable. This is preferable because it is rich in transparency, heat resistance and flexibility.

  Such a norbornene polymer is suitably synthesized by using, for example, a norbornene monomer described later (a norbornene monomer represented by Chemical Formula 3 described below or a crosslinkable norbornene monomer).

  In order to obtain a polymer 915 having a relatively high refractive index, a monomer having an aromatic ring (aromatic group), a nitrogen atom, a bromine atom or a chlorine atom in the molecular structure is generally selected, A polymer 915 is synthesized (polymerized). On the other hand, in order to obtain a polymer 915 having a relatively low refractive index, a monomer having an alkyl group, a fluorine atom or an ether structure (ether group) is generally selected in the molecular structure, and the polymer 915 is synthesized ( Polymerization).

  As the norbornene-based polymer having a relatively high refractive index, those containing a repeating unit of aralkylnorbornene are preferable. Such norbornene-based polymers have a particularly high refractive index.

  Examples of the aralkyl group (arylalkyl group) of the aralkylnorbornene repeating unit include benzyl group, phenylethyl group, phenylpropyl group, phenylbutyl group, naphthylethyl group, naphthylpropyl group, fluorenylethyl group, fluorene group, and the like. Examples thereof include a nylpropyl group, and a benzyl group and a phenylethyl group are particularly preferable.

  A norbornene-based polymer having such a repeating unit is preferable because it has a very high refractive index.

  Further, the norbornene-based polymer preferably contains an alkylnorbornene repeating unit. Since the norbornene-based polymer containing the alkylnorbornene repeating unit has high flexibility, high flexibility (flexibility) can be imparted to the optical waveguide 90 by using such norbornene-based polymer.

  Examples of the alkyl group that the alkylnorbornene repeating unit has include a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, and a decyl group, and a hexyl group is particularly preferable. These alkyl groups may be either linear or branched.

  By including the repeating unit of hexyl norbornene, it is possible to prevent the refractive index of the entire norbornene-based polymer from being lowered and to maintain high flexibility. Such a norbornene-based polymer is preferable because of its excellent transmittance with respect to light in the wavelength region as described above (particularly in the wavelength region near 850 nm).

  Preferred examples of such norbornene polymers include hexyl norbornene homopolymer, phenylethyl norbornene homopolymer, benzyl norbornene homopolymer, hexyl norbornene and phenylethyl norbornene copolymer, and hexyl norbornene and benzyl norbornene copolymer. However, it is not limited to these.

  The core layer forming material of this embodiment includes a monomer, a promoter (first substance), and a catalyst precursor (second substance) as the additive 920.

  The monomer reacts with an actinic radiation, which will be described later, to form a reaction product in an irradiation region of the active radiation, and due to the presence of the reaction product, an irradiation region in the second layer 1120 and an unirradiated region of the active radiation In this case, the compound can cause a difference in refractive index.

  Here, as this reaction product, a polymer (polymer) formed by polymerizing a monomer in a polymer (matrix) 915, a crosslinked structure that cross-links the polymers 915, and a polymer 915 that is polymerized from the polymer 915 Examples thereof include at least one of branched structures (branch polymer and side chain (pendant group)).

  Here, in the second layer 1120, when it is desired that the refractive index of the irradiated region be high, a polymer 915 having a relatively low refractive index, a monomer having a high refractive index with respect to the polymer 915, and Are used in combination, and it is desired that the refractive index of the irradiated region be lowered, a polymer 915 having a relatively high refractive index and a monomer having a low refractive index for this polymer 915 are used in combination. Is done.

  Note that “high” or “low” in the refractive index does not mean the absolute value of the refractive index but means a relative relationship between certain materials.

  When the refractive index of the irradiated region in the second layer 1120 decreases due to the reaction of the monomer (reactant generation), the portion becomes the cladding portion 95, and when the refractive index of the irradiated region increases, the portion It becomes the core part 94.

  Such a monomer is not particularly limited as long as it is a compound having a polymerizable site, and examples thereof include norbornene monomers, acrylic acid (methacrylic acid) monomers, epoxy monomers, styrene monomers, and the like. These can be used alone or in combination of two or more.

  Among these, it is preferable to use a norbornene-based monomer as the monomer. By using the norbornene-based monomer, it is possible to obtain the core layer 93 (optical waveguide 90) having excellent optical transmission performance and excellent heat resistance and flexibility.

  Here, the norbornene-based monomer is a generic term for monomers containing at least one norbornene skeleton represented by the following chemical formula 2 (structural formula A), and examples thereof include compounds represented by the following chemical formula 3 (structural formula C). .

［式中、ａは、単結合または二重結合を表し、Ｒ¹〜Ｒ⁴は、それぞれ独立して、水素原子、置換もしくは無置換の炭化水素基、または官能置換基を表し、ｍは、０〜５の整数を表す。ただし、ａが二重結合の場合、Ｒ¹およびＲ²のいずれか一方、Ｒ³およびＲ⁴のいずれか一方は存在しない。］

[Wherein, a represents a single bond or a double bond, R ^{1 to} R ⁴ each independently represents a hydrogen atom, a substituted or unsubstituted hydrocarbon group, or a functional substituent; Represents an integer of 0 to 5; However, when a is a double bond, either one of R ¹ and R ² or one of R ³ and R ⁴ does not exist. ]

Examples of the unsubstituted hydrocarbon group (hydrocarbyl group) include, for example, a linear or branched alkyl group having 1 to 10 carbon atoms (C _{1 to} C ₁₀ ), a linear or branched carbon number of 2 -10 (C ₂ -C ₁₀ alkenyl group, linear or branched alkynyl group having 2 to 10 carbon atoms (C ₂ -C ₁₀ ), cycloalkyl having 4 to 12 carbon atoms (C ₄ -C ₁₂ ) Group, a C 4-12 (C ₄ -C ₁₂ ) cycloalkenyl group, a C 6-12 (C ₆ -C ₁₂ ) aryl group, and a C 7-24 (C ₇ -C ₂₄ ) aralkyl group In addition, R ¹ and R ² , R ³ and R ⁴ may each be an alkylidenyl group having 1 to 10 carbon atoms (C _{1 to} C ₁₀ ).

  Specific examples of the alkyl group include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, neopentyl group, hexyl group, heptyl group, octyl group. , Nonyl and decyl groups, but are not limited thereto.

  Specific examples of the alkenyl group include, but are not limited to, a vinyl group, an allyl group, a butenyl group, and a cyclohexenyl group.

  Specific examples of the alkynyl group include, but are not limited to, ethynyl group, 1-propynyl group, 2-propynyl group, 1-butynyl group and 2-butynyl group.

  Specific examples of the cycloalkyl group include, but are not limited to, a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group.

  Specific examples of the aryl group include, but are not limited to, a phenyl group, a naphthyl group, and an anthracenyl group.

  Specific examples of the aralkyl group include, but are not limited to, a benzyl group and a phenylethyl (phenethyl) group.

  Further, specific examples of the alkylidenyl group include, but are not limited to, a methylidenyl group and an ethylidenyl group.

  Examples of the substituted hydrocarbon group include those in which some or all of the hydrogen atoms of the hydrocarbon group are substituted with halogen atoms, that is, halohydrocarbyl groups, perhalohydrocarbyl groups. Or halogenated hydrocarbon groups such as perhalocarbyl groups.

  In these halogenated hydrocarbon groups, the halogen atom substituted with a hydrogen atom is preferably at least one selected from a chlorine atom, fluorine and bromine, more preferably a fluorine atom.

  Among these, specific examples of the perhalogenated hydrocarbon group (perhalohydrocarbyl group, perhalocarbyl group) include, for example, a perfluorophenyl group, a perfluoromethyl group (trifluoromethyl group), and a perfluoroethyl group. Perfluoropropyl group, perfluorobutyl group, perfluorohexyl group and the like.

As the halogenated alkyl group, those having 11 to 20 carbon atoms can be suitably used in addition to those having 1 to 10 carbon atoms. That is, as the halogenated alkyl group, a group that is partially or completely halogenated, linear or branched, and represented by the general formula: —C _Z X ″ _{2Z + 1} can be selected. . Here, X '' represents a halogen atom or a hydrogen atom each independently, and Z represents the integer of 1-20.

In addition to the halogen atom, the substituted hydrocarbon group may be a linear or branched alkyl group having 1 to 5 carbon atoms (C ₁ -C ₅ ), a haloalkyl group, an aryl group, and a cycloalkyl group. Examples thereof include a substituted cycloalkyl group, aryl group and aralkyl group (aralkyl group).

Moreover, as a functional substituent, for example, — (CH ₂ ) _n —CH (CF ₂ ) ₂ —O—Si (Me) ₃ , — (CH ₂ ) _n —CH (CF ₃ ) ₂ —O—CH ₂ —O—CH ₃ , — (CH ₂ ) _n —CH (CF ₃ ) ₂ —O—C (O) —O—C (CH ₃ ) ₃ , — (CH ₂ ) _n —C (CF ₃ ) ₂ — OH, — (CH ₂ ) _n —C (O) —NH ₂ , — (CH ₂ ) _n —C (O) —Cl, — (CH ₂ ) _n —C (O) —O—R ⁵ , — ( _{CH 2) n-O-R} 5, - (CH 2) n -O-C (O) -R 5, - (CH 2) n -C (O) -R 5, - (CH 2) n -O ^{-C (O) -OR 5, -} (CH 2) n -Si (R 5) 3, - (CH 2) n -Si (OR 5) 3, - (CH 2) n -O-Si (R 5 ) ₃ and — (CH ₂ ) _n —C (O) —OR ^{6 and the} like.

Here, in each of the formulas above, each, n is an integer of 0, R ⁵ are each independently a hydrogen atom, a linear or branched C 1 to 20 (C ₁ -C ₂₀₎ alkyl group, a linear or branched halogenated or perhalogenated alkyl group having a carbon number 1 to 20 (C ₁ -C ₂₀₎ linear or branched C 2 to 10 (C ₂ ~ alkenyl group of C _10), a linear or branched alkynyl group having 2 to 10 carbon atoms (C ₂ ~C _10), a cycloalkyl group having 5 to 12 carbon atoms (C ₅ ~C _12), to 6 carbon atoms -14 (C ₆ -C ₁₄ ) aryl group, C 6-14 (C ₆ -C ₁₄ ) halogenated or perhalogenated aryl group or C 7-24 (C ₇ -C ₂₄ ) aralkyl group Represents.

Incidentally, the hydrocarbon group represented by R ⁵ represents the same hydrocarbon groups as those represented by R ¹ to R ^4. As represented by R ^{1 to} R ⁴ , the hydrocarbon group represented by R ⁵ may be halogenated or perhalogenated.

For example, when R ⁵ is a halogenated or perhalogenated alkyl group having 1 to 20 carbon atoms (C _{1 to} C ₂₀ ), R ⁵ is represented by the general formula: —C _Z X ″ _{2Z + 1} . Here, z and X ″ are the same as defined above, and at least one of X ″ is a halogen atom (for example, a bromine atom, a chlorine atom, or a fluorine atom).

Here, the perhalogenated alkyl group is a group in which all X ″ in the general formula is a halogen atom, and specific examples thereof include a trifluoromethyl group, a trichloromethyl group, —C ₇ F _15. Although -C ₁₁ F ₂₃ and the like, but are not limited to.

  Specific examples of the perhalogenated aryl group include, but are not limited to, a pentachlorophenyl group and a pentafluorophenyl group.

Examples of R ⁶ include —C (CH ₃ ) ₃ , —Si (CH ₃ ) ₃ , —CH (R ⁷ ) —O—CH ₂ CH ₃ , —CH (R ⁷ ) OC (CH ₃ ). ₃ and the cyclic group of the following chemical formula 4 and the like.

ここで、Ｒ⁷は、水素原子、あるいは直鎖状または分岐状の炭素数１〜５（Ｃ₁〜Ｃ₅）のアルキル基を表す。

Here, R ⁷ represents a hydrogen atom or a linear or branched alkyl group having ₁ to ₅ carbon atoms (C _{1 to} C ₅ ).

  Examples of the alkyl group include methyl group, ethyl group, propyl group, i-propyl group, butyl group, i-butyl group, t-butyl, pentyl group, t-pentyl group, and neopentyl group.

  In the cyclic group represented by Chemical Formula 4, an ester bond is formed between the single bond extending from the ring structure and the acid substituent.

Specific examples of R ⁶ include, for example, a 1-methyl-1-cyclohexyl group, an isobornyl group, a 2-methyl-2-isobornyl group, a 2-methyl-2-adamantyl group, a tetrahydrofuranyl group, Examples thereof include a tetrahydropyranoyl group, a 3-oxocyclohexanoyl group, a mevalonic lactonyl group, a 1-ethoxyethyl group, and a 1-t-butoxyethyl group.

Other examples of R ⁶ include a dicyclopropylmethyl group (Dcpm) and a dimethylcyclopropylmethyl group (Dmcp) represented by the following chemical formula 5.

  Moreover, it can replace with said monomer for a monomer, or can also use a crosslinkable monomer (crosslinking agent) with said monomer. This crosslinkable monomer is a compound capable of causing a crosslinking reaction in the presence of a catalyst precursor described later.

  The use of the crosslinkable monomer has the following advantages. That is, since the crosslinkable monomer is polymerized faster, the time required for the formation (process) of the core layer 93 (optical waveguide 90) can be shortened. Moreover, since the crosslinkable monomer is difficult to evaporate even when heated, an increase in vapor pressure can be suppressed. Furthermore, since the crosslinkable monomer is excellent in heat resistance, the heat resistance of the core layer 93 can be improved.

  Among these, the crosslinkable norbornene-based monomer is a compound including a norbornene-based moiety (norbornene-based double bond) represented by Formula 2 (Structural Formula A).

  As the crosslinkable norbornene-based monomer, there are a compound of a continuous polycyclic ring system and a compound of a linked multicyclic ring system.

  Examples of the continuous polycyclic ring-based compound (continuous polycyclic ring-based crosslinkable norbornene-based monomer) include compounds represented by the following chemical formula (6).

［式中、Ｙは、メチレン（−ＣＨ₂−）基を表し、ｍは、０〜５の整数を表わす。ただし、ｍが０である場合、Ｙは、単結合である。］

[Wherein Y represents a methylene (—CH ₂ —) group, and m represents an integer of 0 to 5. However, when m is 0, Y is a single bond. ]

  For simplicity, norbornadiene is considered to be included in a continuous polycyclic ring system and includes a polymerizable norbornene double bond.

  Specific examples of this continuous polycyclic compound include, but are not limited to, compounds represented by the following chemical formula (7).

  On the other hand, examples of the linked polycyclic ring-based compound (linked polycyclic ring-based crosslinkable norbornene-based monomer) include compounds represented by the following chemical formula (8).

［式中、ａは、それぞれ独立して、単結合または二重結合を表し、ｍは、それぞれ独立して、０〜５の整数を表し、Ｒ⁹は、それぞれ独立して二価の炭化水素基、二価のエーテル基または二価のシリル基を表す。また、ｎは、０または１である。］

[Wherein, a independently represents a single bond or a double bond, m represents each independently an integer of 0 to 5, and R ⁹ each independently represents a divalent hydrocarbon. Represents a group, a divalent ether group or a divalent silyl group. N is 0 or 1. ]

  Here, the divalent substituent refers to a group having two bonds that can be bonded to the norbornene structure at the end.

Specific examples of the divalent hydrocarbon group (hydrocarbyl group) include an alkylene group represented by the general formula: — (C _d H _2d ) — (d is preferably an integer of 1 to 10). And a divalent aromatic group (aryl group).

The divalent alkylene group is preferably a linear or branched alkylene group having 1 to 10 carbon atoms (C _{1 to} C ₁₀ ), such as a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, Examples include a hexylene group, a heptylene group, an octylene group, a nonylene group, and a decylene group.

  The branched alkylene group is one in which a main chain hydrogen atom is substituted with a linear or branched alkyl group.

On the other hand, the divalent aromatic group is preferably a divalent phenyl group or a divalent naphthyl group.
The divalent ether group is a group represented by —R ¹⁰ —O—R ¹⁰ —.
Here, R < ¹⁰ > represents the same thing as R < ⁹ > each independently.

  Specific examples of this linked polycyclic ring compound include compounds represented by the following chemical formula 9, chemical formula 10, chemical formula 11, chemical formula 12, chemical formula 13, and fluorine-containing compounds represented by chemical formulas 14 and 15 ( Fluorine-containing crosslinkable norbornene-based monomer), but is not limited thereto.

  The compound represented by the chemical formula 10 is dimethylbis [bicyclo [2.2.1] hept-2-ene-5-methoxy] silane, and is named dimethylbis (norbornenemethoxy) silane (“ Abbreviated as “SiX”).

［式中、ｎは、０〜４の整数を表す。］

[Wherein, n represents an integer of 0 to 4. ]

［式中、ｍおよびｎは、それぞれ、１〜４の整数を表す。］

[Wherein, m and n each represent an integer of 1 to 4. ]

  Among various crosslinkable norbornene monomers, dimethylbis (norbornenemethoxy) silane (SiX) is particularly preferable. SiX has a sufficiently low refractive index with respect to a norbornene-based polymer containing a repeating unit of alkylnorbornene and / or a repeating unit of aralkylnorbornene. For this reason, the refractive index of the irradiation region irradiated with actinic radiation, which will be described later, can be reliably lowered to form the clad portion 95. Moreover, the refractive index difference between the core part 94 and the clad part 95 can be increased, and the characteristics (optical transmission performance) of the core layer 93 (optical waveguide 90) can be improved.

  In addition, you may make it use the above monomers individually or in arbitrary combinations.

  The catalyst precursor (second substance) is a substance capable of initiating the above-described monomer reaction (polymerization reaction, crosslinking reaction, etc.), and is a promoter (first substance) activated by irradiation with actinic radiation described later. It is a substance whose activation temperature changes by the action of.

  As the catalyst precursor (procatalyst), any compound may be used as long as the activation temperature changes (increases or decreases) with irradiation of actinic radiation. Those whose activation temperature decreases with irradiation are preferred. As a result, the core layer 93 (optical waveguide 90) can be formed by heat treatment at a relatively low temperature, and unnecessary heat is applied to the other layers, which degrades the characteristics (optical transmission performance) of the optical waveguide 90. Can be prevented.

  As such a catalyst precursor, a catalyst precursor containing (mainly) at least one of the compounds represented by the following formulas (Ia) and (Ib) is preferably used.

［式Ｉａ、Ｉｂ中、それぞれ、Ｅ（Ｒ）₃は、第１５族の中性電子ドナー配位子を表し、Ｅは、周期律表の第１５族から選択される元素を表し、Ｒは、水素原子（またはその同位体の１つ）または炭化水素基を含む部位を表し、Ｑは、カルボキシレート、チオカルボキシレートおよびジチオカルボキシレートから選択されるアニオン配位子を表す。また、式Ｉｂ中、ＬＢは、ルイス塩基を表し、ＷＣＡは、弱配位アニオンを表し、ａは、１〜３の整数を表し、ｂは、０〜２の整数を表し、ａとｂとの合計は、１〜３であり、ｐおよびｒは、パラジウムカチオンと弱配位アニオンとの電荷のバランスをとる数を表す。］

[In the formulas Ia and Ib, each E (R) ₃ represents a neutral electron donor ligand of Group 15; E represents an element selected from Group 15 of the periodic table; , Represents a moiety containing a hydrogen atom (or one of its isotopes) or a hydrocarbon group, and Q represents an anionic ligand selected from carboxylate, thiocarboxylate and dithiocarboxylate. In Formula Ib, LB represents a Lewis base, WCA represents a weakly coordinating anion, a represents an integer of 1 to 3, b represents an integer of 0 to 2, and a and b , P and r represent numbers that balance the charge of the palladium cation and the weakly coordinated anion. ]

Typical catalyst precursors according to Formula Ia include Pd (OAc) ₂ (P (i-Pr) ₃ ) ₂ , Pd (OAc) ₂ (P (Cy) ₃ ) ₂ , Pd (O ₂ CCMe ₃ ) ₂ (P (Cy) ₃ ) ₂ , Pd (OAc) ₂ (P (Cp) ₃ ) ₂ , Pd (O ₂ CCF ₃ ) ₂ (P (Cy) ₃ ) ₂ , Pd (O ₂ CC ₆ H ₅ ) ₃ (P (Cy) ₃ ) ₂ may be mentioned, but is not limited thereto. Here, Cp represents a cyclopentyl group, and Cy represents a cyclohexyl group.

  The catalyst precursor represented by the formula Ib is preferably a compound in which p and r are each selected from integers of 1 and 2.

Typical catalyst precursors according to such formula Ib include Pd (OAc) ₂ (P (Cy) ₃ ) ₂ . Here, Cy represents a cyclohexyl group, and Ac represents an acetyl group.

  These catalyst precursors can efficiently react with a monomer (in the case of a norbornene-based monomer, an efficient polymerization reaction, a crosslinking reaction, etc. by an addition polymerization reaction).

  In the state where the activation temperature is lowered (active latent state), the catalyst precursor has an activation temperature lower by about 10 to 80 ° C. (preferably about 10 to 50 ° C.) than the original activation temperature. Is preferred. Thereby, the refractive index difference between the core part 94 and the clad part 95 can be produced reliably.

Such a catalyst precursor includes (mainly) one containing at least one of Pd (OAc) ₂ (P (i-Pr) ₃ ) ₂ and Pd (OAc) ₂ (P (Cy) ₃ ) _2. Is preferred.

Hereinafter, Pd (OAc) ₂ (P (i-Pr) ₃ ) ₂ may be abbreviated as “Pd545”, and Pd (OAc) ₂ (P (Cy) ₃ ) ₂ may be abbreviated as “Pd785”. .

  The cocatalyst (first substance) is a substance that can be activated by irradiation with actinic radiation to change the activation temperature of the catalyst precursor (procatalyst) (the temperature at which the monomer reacts).

  As the cocatalyst (cocatalyst), any compound can be used as long as it has a molecular structure that changes (reacts or decomposes) when activated by irradiation with actinic radiation. A compound (photoinitiator) that decomposes upon irradiation with actinic radiation and generates a cation such as a proton or other cation and a weakly coordinated anion (WCA) that can be substituted with a leaving group of the catalyst precursor ( (Mainly) is preferably used.

Examples of the weak coordination anion include tetrakis (pentafluorophenyl) borate ion (FABA ⁻ ), hexafluoroantimonate ion (SbF ₆ ⁻ ), and the like.

  Examples of the cocatalyst (photoacid generator or photobase generator) include tetrakis (pentafluorophenyl) borate and hexafluoroantimonate represented by the following chemical formula 17, tetrakis (pentafluorophenyl) Examples include gallates, aluminates, antimonates, other borates, gallates, carboranes, halocarboranes, and the like.

  As a commercial product of such a promoter, for example, “RHODORSIL (registered trademark, the same applies hereinafter) PHOTOINITIATOR 2074 (CAS No. 178233-72-2) available from Rhodia USA, Cranberry, NJ "TAG-372R ((dimethyl (2- (2-naphthyl) -2-oxoethyl) sulfonium tetrakis (pentafluorophenyl) borate: CAS No. 193957) available from Toyo Ink Manufacturing Co., Ltd., Tokyo, Japan" -54-9)), "MPI-103 (CAS No. 87709-41-9)" available from Midori Chemical Co., Tokyo, Japan, available from Toyo Ink Manufacturing Co., Ltd., Tokyo, Japan "TAG-371 (CAS No. 193957-53-8) "TTBPS-TPFPB (tris (4-tert-butylphenyl) sulfonium tetrakis (pentapentafluorophenyl) borate)" available from Toyo Gosei Co., Ltd., Tokyo, Japan Examples thereof include “NAI-105 (CAS number 85342-62-7)” available from the company.

  When RHODORSIL PHOTOINITIATOR 2074 is used as the cocatalyst (first substance), ultraviolet rays (UV light) are preferably used as actinic radiation (chemical rays) described later, and mercury lamps ( A high-pressure mercury lamp) is preferably used. Thereby, ultraviolet rays (active radiation) having sufficient energy of less than 300 nm can be supplied to the stacked body 2000 (second layer 1120), and RHODOLSIL PHOTOINITIATOR 2074 is efficiently decomposed, and the above cations and WCA can be generated.

  Moreover, you may make it add a sensitizer in the core layer forming material (2nd varnish) as needed.

  The sensitizer increases the sensitivity of the cocatalyst to actinic radiation, reduces the time and energy required for the activation (reaction or decomposition) of the cocatalyst, and the wavelength of the actinic radiation to a wavelength suitable for the activation of the cocatalyst It has a function of changing the wavelength.

  Such a sensitizer is appropriately selected depending on the sensitivity of the promoter and the peak wavelength of absorption of the sensitizer, and is not particularly limited. For example, 9,10-dibutoxyanthracene (CAS No. 76275) is selected. 14-4) anthracenes, xanthones, anthraquinones, phenanthrenes, chrysenes, benzpyrenes, fluoranthenes, rubrenes, pyrenes, indanthrines, thioxanthen-9-ones (Thioxanthen-9-ones) and the like, and these are used alone or as a mixture.

  Specific examples of the sensitizer include 2-isopropyl-9H-thioxanthen-9-one, 4-isopropyl-9H-thioxanthen-9-one, 1-chloro-4-propoxythioxanthone, phenothiazine, and these Of the mixture.

  9,10-dibutoxyanthracene (DBA) can be obtained from Kawasaki Kasei Kogyo Co., Ltd., Kanagawa, Japan.

  The content of the sensitizer in the core layer forming material (second varnish) is not particularly limited, but is preferably 0.01% by weight or more, and more preferably 0.5% by weight or more. More preferably, it is 1% by weight or more. In addition, it is preferable that an upper limit is 5 weight% or less.

  Furthermore, an antioxidant can be added to the core layer forming material. Thereby, generation | occurrence | production of an undesired free radical and the natural oxidation of the polymer 915 can be prevented. As a result, the characteristics of the obtained core layer 93 (optical waveguide 90) can be improved.

  Examples of the antioxidant include Ciba (registered trademark, the same applies hereinafter) IRGANOX (registered trademark, the same applies hereinafter) 1076 and Ciba IRGAFOS (registered trademark, available) from Ciba Specialty Chemicals of Tarrytown, New York. The same applies hereinafter.) 168 is preferably used.

  Other antioxidants include, for example, Ciba Irganox (registered trademark, hereinafter the same) 129, Ciba Irganox 1330, Ciba Irganox 1010, Ciba Cyanox (registered trademark, the same applies below) 1790, Ciba Irg. (Registered trademark) 3114, Ciba Irganox 3125, etc. can also be used.

  Note that such an antioxidant can be omitted, for example, when the second layer 1120 (stacked body 2000) is not exposed to oxidation conditions or when the exposure period is extremely short.

  Examples of the solvent used for preparing the core layer forming material (second varnish) include diethyl ether, diisopropyl ether, 1,2-dimethoxyethane (DME), 1,4-dioxane, tetrahydrofuran (THF), and tetrahydropyran. (THP), anisole, diethylene glycol dimethyl ether (diglyme), ether solvents such as diethylene glycol ethyl ether (carbitol), cellosolv solvents such as methyl cellosolve, ethyl cellosolve, phenyl cellosolve, aliphatics such as hexane, pentane, heptane, cyclohexane Hydrocarbon solvents, aromatic hydrocarbon solvents such as toluene, xylene, benzene, mesitylene, aromatic heterocyclic compounds solvents such as pyridine, pyrazine, furan, pyrrole, thiophene, methylpyrrolidone, Amide solvents such as N, N-dimethylformamide (DMF) and N, N-dimethylacetamide (DMA), halogen compound solvents such as dichloromethane, chloroform and 1,2-dichloroethane, ethyl acetate, methyl acetate, ethyl formate, etc. Examples thereof include various organic solvents such as ester solvents, sulfur compound solvents such as dimethyl sulfoxide (DMSO) and sulfolane, and mixed solvents containing these.

[3A] Next, a clad layer forming material (third varnish) including a clad material is applied onto the second layer 1120 by the same method as described above to form a liquid film. The third layer 1130 in a state where the liquid film does not completely solidify or cure (unsolidified or uncured) is formed (see FIG. 4).

The average thickness of the third layer 1130 is not particularly limited, but is preferably about 5 to 200 μm, more preferably about 10 to 100 μm, and still more preferably about 15 to 65 μm.
Thereby, the laminated body 2000 is obtained.

  Examples of the constituent material (cladding material) of the clad layer 91 (92) include acrylic resin, methacrylic resin, polycarbonate, polystyrene, epoxy resin, polyamide, polyimide, polybenzoxazole, benzocyclobutene resin, and norbornene resin. Cyclic olefin-based resins, etc. can be used, and one or more of these can be used in combination (polymer alloy, polymer blend (mixture), copolymer, composite (laminate), etc.). .

  Of these, epoxy resins, polyimides, polybenzoxazoles, cyclic olefin resins such as benzocyclobutene resins and norbornene resins, and those containing them (mainly) in terms of particularly excellent heat resistance It is preferable to use, and particularly, those mainly composed of norbornene-based resins (norbornene-based polymers) are preferable.

  Since the norbornene-based polymer has extremely high heat resistance, when the conductor layers 901 and 902 are formed on the optical waveguide 90 in the optical waveguide 90 using this as a constituent material of the cladding layer 91 (92), the conductor layers 901 and 902 are formed. Even when heated to mount an optical element or the like when forming the wiring by processing, the cladding layer 91 (92) can be softened and prevented from being deformed.

  Moreover, since it has high hydrophobicity, it is possible to obtain the clad layer 91 (92) that is less likely to undergo dimensional changes due to water absorption.

  Norbornene-based polymers or norbornene-based monomers that are raw materials thereof are also preferable because they are relatively inexpensive and easily available.

  Further, when a material mainly composed of norbornene-based polymer is used as the material of the clad layer 91 (92), the material is preferably the same as the material suitably used as the constituent material of the core layer 93. Further, it becomes higher, and delamination between the clad layer 91 (92) and the core layer 93 can be prevented. For this reason, the optical waveguide 90 having excellent durability can be obtained.

  Examples of such norbornene-based polymers include (1) addition (co) polymers of norbornene monomers obtained by addition (co) polymerization of norbornene monomers, and (2) norbornene monomers and ethylene or α-olefins. (3) addition polymers such as addition copolymers with norbornene-type monomers and non-conjugated dienes, and other monomers as required, (4) ring opening of norbornene-type monomers ( A (co) polymer, and a resin obtained by hydrogenating the (co) polymer if necessary, (5) a ring-opening copolymer of a norbornene-type monomer and ethylene or α-olefins, and ( (Co) polymer hydrogenated resin, (6) ring-opening copolymer of norbornene type monomer and non-conjugated diene or other monomer, and (co) polymerization if necessary And a ring-opening polymer such as a polymer obtained by hydrogenating the body. Examples of these polymers include random copolymers, block copolymers, and alternating copolymers.

  These norbornene-based polymers include, for example, ring-opening metathesis polymerization (ROMP), combination of ROMP and hydrogenation reaction, polymerization by radical or cation, polymerization using a cationic palladium polymerization initiator, and other polymerization initiators ( For example, it can be obtained by any known polymerization method such as polymerization using a polymerization initiator of nickel or another transition metal).

  Among these, as the norbornene-based polymer, an addition (co) polymer is preferable. This is preferable because it is rich in transparency, heat resistance and flexibility.

  In particular, the norbornene-based polymer preferably includes a norbornene repeating unit having a substituent containing a polymerizable group or a norbornene repeating unit having a substituent containing an aryl group.

  By including a norbornene repeating unit having a substituent containing a polymerizable group, in the cladding layer 91 (92), the polymerizable groups of at least some of the norbornene-based polymers are crosslinked directly or via a crosslinking agent. be able to. Depending on the type of polymerizable group, the type of crosslinking agent, the type of polymer used for the core layer 93, the norbornene-based polymer and the polymer used for the core layer 93 can be cross-linked. In other words, it is preferable that at least a part of the norbornene-based polymer is crosslinked at the polymerizable group.

  As a result, the strength of the clad layer 91 (92) itself and the adhesion between the clad layer 91 (92) and the core layer 93 can be further improved.

  Examples of the norbornene repeating unit containing a polymerizable group include a norbornene repeating unit having a substituent containing an epoxy group, a norbornene repeating unit having a substituent containing a (meth) acryl group, and an alkoxysilyl group. At least one of the repeating units of norbornene having a substituent to be included is preferable. These polymerizable groups are preferable because of their high reactivity among various polymerizable groups.

  Moreover, if the thing containing 2 or more types of norbornene repeating units containing such a polymeric group is used, a crosslinking density can be improved further and the said effect will become more remarkable.

  On the other hand, by including a norbornene repeating unit having a substituent containing an aryl group, the aryl group has extremely high hydrophobicity, so that the dimensional change due to water absorption of the cladding layer 91 (92) can be more reliably prevented. it can. In addition, since the aryl group is excellent in fat solubility (lipophilicity) and has a high affinity with the polymer used in the core layer 93 as described above, an interlayer between the clad layer 91 (92) and the core layer 93 is used. Separation can be prevented more reliably, and an optical waveguide 90 with higher durability can be obtained.

  Furthermore, the norbornene-based polymer preferably contains an alkylnorbornene repeating unit. The alkyl group may be linear or branched.

  By including the repeating unit of alkyl norbornene, the norbornene-based polymer has high flexibility, so that high flexibility (flexibility) can be imparted to the cladding layers 91 and 92 (optical waveguide 90).

  A norbornene-based polymer containing an alkylnorbornene repeating unit is also preferable because of its excellent transmittance for light in the wavelength region as described above (particularly in the wavelength region near 850 nm).

  The norbornene-based polymer used for the clad layer 91 (92) is preferably a polymer having a relatively low refractive index. On the other hand, if the norbornene-containing polymer having a substituent containing an aryl group is included, the norbornene-based polymer generally has a refractive index. However, an increase in the refractive index can be prevented by including an alkyl norbornene repeating unit.

  Therefore, as the norbornene-based polymer used for the clad layer 91 (92), those represented by the following chemical formulas 18 to 21 and chemical formula 25 are preferable.

［式中、Ｒは、炭素数１〜１０のアルキル基を表し、ａは、０〜３の整数を表し、ｂは、１〜３の整数を表し、ｐ／ｑが２０以下である。］

[Wherein R represents an alkyl group having 1 to 10 carbon atoms, a represents an integer of 0 to 3, b represents an integer of 1 to 3, and p / q is 20 or less. ]

  Among the norbornene-based polymers represented by Chemical formula 18, a compound in which R is an alkyl group having 4 to 10 carbon atoms and a and b are each 1, for example, a copolymer of butylbornene and methylglycidyl ether norbornene A copolymer of hexyl norbornene and methyl glycidyl ether norbornene, a copolymer of decyl norbornene and methyl glycidyl ether norbornene, and the like are preferable.

［式中、Ｒは、炭素数１〜１０のアルキル基を表し、Ｒ¹は、水素原子またはメチル基を表し、ａは、０〜３の整数を表し、ｐ／ｑが２０以下である。］

[Wherein, R represents an alkyl group having 1 to 10 carbon atoms, R ¹ represents a hydrogen atom or a methyl group, a represents an integer of 0 to 3, and p / q is 20 or less. ]

  Of the norbornene-based polymers represented by Chemical formula 19, compounds in which R is an alkyl group having 4 to 10 carbon atoms and a is 1, for example, butylbornene and 2- (5-norbornenyl) methyl acrylate And a copolymer of hexylnorbornene and 2- (5-norbornenyl) methyl acrylate, a copolymer of decylnorbornene and 2- (5-norbornenyl) methyl acrylate, and the like.

［式中、Ｒは、炭素数１〜１０のアルキル基を表し、Ｘは、それぞれ独立して、炭素数１〜３のアルキル基を表し、ａは、０〜３の整数を表し、ｐ／ｑが２０以下である。］

[Wherein, R represents an alkyl group having 1 to 10 carbon atoms, X represents each independently an alkyl group having 1 to 3 carbon atoms, a represents an integer of 0 to 3, and p / q is 20 or less. ]

  Among the norbornene-based polymers represented by Chemical Formula 20, in particular, compounds in which R is an alkyl group having 4 to 10 carbon atoms, a is 1 or 2, and X is a methyl group or an ethyl group, such as butylbornene Copolymer of norbornenylethyltrimethoxysilane, copolymer of hexylnorbornene and norbornenylethyltrimethoxysilane, copolymer of decylnorbornene and norbornenylethyltrimethoxysilane, copolymer of butylbornene and triethoxysilylnorbornene, hexyl Copolymers of norbornene and triethoxysilyl norbornene, copolymers of decyl norbornene and triethoxysilyl norbornene, copolymers of butylbornene and trimethoxysilyl norbornene, hexyl norbornene and tri Copolymers of butoxy silyl norbornene copolymer and the like of decyl norbornene and trimethoxysilyl norbornene are preferred.

［式中、Ｒは、炭素数１〜１０のアルキル基を表し、Ａ¹およびＡ²は、それぞれ独立して、下記化２２〜２４で表される置換基を表すが、同時に同一の置換基であることはない。また、ｐ／ｑ＋ｒが２０以下である。］

[Wherein, R represents an alkyl group having 1 to 10 carbon atoms, and A ¹ and A ² each independently represent a substituent represented by the following chemical formulas 22 to 24, but at the same time, the same substituent Never. Moreover, p / q + r is 20 or less. ]

［式中、ａは、０〜３の整数を表し、ｂは、１〜３の整数を表す。］

[Wherein, a represents an integer of 0 to 3, and b represents an integer of 1 to 3. ]

［式中、Ｒ¹は、水素原子またはメチル基を表し、ａは、０〜３の整数を表す。］

[Wherein, R ¹ represents a hydrogen atom or a methyl group, and a represents an integer of 0 to 3. ]

［式中、Ｘは、それぞれ独立して、炭素数１〜３のアルキル基を表し、ａは、０〜３の整数を表す。］

[In formula, X represents a C1-C3 alkyl group each independently, and a represents the integer of 0-3. ]

  As the norbornene-based polymer represented by Chemical formula 21, for example, any of butylbornene, hexylnorbornene or decylnorbornene, 2- (5-norbornenyl) methyl acrylate, norbornenylethyltrimethoxysilane, triethoxysilyl Terpolymers with either norbornene or trimethoxysilyl norbornene, terpolymers of either butylbornene, hexyl norbornene or decyl norbornene with 2- (5-norbornenyl) methyl acrylate and methylglycidyl ether norbornene, butylbornene, hexyl norbornene or One of decyl norbornene, methyl glycidyl ether norbornene, norbornenyl ethyl trimethoxysilane, triethoxysilyl norbornene Terpolymers, etc. with either Nen or trimethoxysilyl norbornene.

［式中、Ｒは、炭素数１〜１０のアルキル基を表し、Ｒ²は、水素原子、メチル基またはエチル基を表し、Ａｒは、アリール基を表し、Ｘ¹は、酸素原子またはメチレン基を表し、Ｘ²は、炭素原子またはシリコン原子を表し、ａは、０〜３の整数を表し、ｃは、１〜３の整数を表し、ｐ／ｑが２０以下である。］

[Wherein, R represents an alkyl group having 1 to 10 carbon atoms, R ² represents a hydrogen atom, a methyl group or an ethyl group, Ar represents an aryl group, and X ¹ represents an oxygen atom or a methylene group. X ² represents a carbon atom or a silicon atom, a represents an integer of 0 to 3, c represents an integer of 1 to 3, and p / q is 20 or less. ]

Among the norbornene-based polymers represented by Chemical Formula 25, in particular, R is an alkyl group having 4 to 10 carbon atoms, X ¹ is an oxygen atom, X ² is a silicon atom, Ar is a phenyl group, and R ² is methyl. A group in which a is 1 and c is 2, for example, a copolymer of butylbornene and diphenylmethylnorbornenemethoxysilane, a copolymer of hexylnorbornene and diphenylmethylnorbornenemethoxysilane, a copolymer of decylnorbornene and diphenylmethylnorbornenemethoxysilane, etc. Or R is an alkyl group having 4 to 10 carbon atoms, X ¹ is a methylene group, X ² is a carbon atom, Ar is a phenyl group, R ² is a hydrogen atom, a is 0, and c is 1, for example, Copolymer of butylbornene and phenylethylnorbornene, hexylnorbornene and phenyl Copolymers of chill norbornene copolymer and the like of decyl norbornene and phenyl ethyl norbornene are preferred.

  Moreover, although p / q or p / q + r should just be 20 or less, it is preferable that it is 15 or less, and about 0.1-10 is more preferable. Thereby, the effect including the repeating unit of multiple types of norbornene is exhibited.

  The norbornene-based polymer as described above has a relatively low refractive index in addition to the above-described characteristics. By forming the clad layer 91 (92) using such a norbornene-based polymer as a main material, the optical waveguide 90 The optical transmission performance can be further improved.

  When the norbornene-based polymer includes a norbornene repeating unit having a substituent containing a (meth) acryl group, the (meth) acryl groups can be crosslinked (polymerized) relatively easily by heating. By mixing a radical generator in the cladding layer forming material, the cross-linking reaction between (meth) acrylic groups can be promoted.

  As the radical generator, for example, 2,2-dimethoxy-1,2-diphenylethane-1-one, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane and the like are preferably used. .

  In addition, when the norbornene-based polymer includes a norbornene repeating unit having a substituent containing an epoxy group or a norbornene repeating unit having a substituent containing an alkoxysilyl group, in order to directly crosslink these polymerizable groups In the clad layer forming material, the same kind of substance (photoacid generator or photobase generator) as the above-mentioned promoter is mixed, and the epoxy group or alkoxysilyl group is crosslinked by the action of this substance. Just do it.

  On the other hand, in order to crosslink epoxy groups, (meth) acrylic groups, or alkoxysilyl groups via a crosslinking agent, it corresponds to each polymerizable group as a crosslinking agent in the cladding layer forming material. A compound having at least one polymerizable group may be mixed.

  As the crosslinking agent having an epoxy group, for example, 3-glycidoxypropyltrimethoxysilane (γ-GPS), silicone epoxy resin, and the like are preferably used.

As a crosslinking agent having a (meth) acryl group, for example, 3-methacryloxypropyltrimethoxysilane tricyclo [5.2.1.0 ^2,6 ] decane dimethanol diacrylate, tripropylene glycol diacrylate, and the like are preferable. Used for.

  As the crosslinking agent having an alkoxysilyl group, for example, a silane coupling agent such as 3-glycidoxypropyltrimethoxysilane or 3-aminopropyltrimethoxysilane is preferably used.

  In the case of this embodiment, it is preferable to perform the crosslinking reaction between these polymerizable groups at the final stage of this step [3A].

  Further, various additives may be added (mixed) to the cladding layer forming material.

  For example, the monomer, the catalyst precursor, and the co-catalyst mentioned in the material for forming the core layer may be mixed in the material for forming the cladding layer. As a result, in the cladding layer 91 (92), the monomer can be reacted to change the refractive index of the cladding layer 91 (92), as will be described later.

  In particular, when a monomer containing a crosslinkable monomer is used as the monomer, at least a part of the norbornene-based polymer in the clad layer 91 (92) can be crosslinked via the crosslinkable monomer. Depending on the type of crosslinking agent, the type of polymer used for the core layer 93, the norbornene-based polymer and the polymer used for the core layer 93 can be cross-linked.

  In this case, since it is not required to provide a difference in refractive index in the clad layer 91 (92), it is possible to omit the promoter and use a catalyst precursor that is easily activated by heating.

Examples of such a catalyst precursor include [Pd (PCy ₃ ) ₂ (O ₂ CCH ₃ ) (NCCH ₃ )] tetrakis (pentafluorophenyl) borate, [2-methyl Pd (PCy3) 2] tetrakis (pentafluorophenyl). ) Borate, [Pd (PCy3) 2H (NCCH3)] tetrakis (pentafluorophenyl) borate, [Pd (P (iPr) 3) 2 (OCOCH3) (NCCH3)] tetrakis (pentafluorophenyl) borate, and the like.

  Examples of other additives include the antioxidants described above. By mixing the antioxidant, it is possible to prevent deterioration of the clad material (norbornene polymer) due to oxidation.

  The first varnish to the third varnish are each prepared so that the viscosity (normal temperature) is preferably about 100 to 10000 cP, more preferably about 150 to 5000 cP, and further preferably about 200 to 3500 cP. Thereby, it is possible to prevent the layers 1110 to 1130 from being mixed more than necessary at their interfaces, and to prevent the thickness of the layers 1110 to 1130 from becoming uneven.

  The viscosity of the second varnish is preferably higher than that of the first varnish. Accordingly, it is possible to reliably prevent the first layer 1110 and the second layer 1120 from being mixed more than necessary at the interface between them.

[4A] Next, the solvent in the laminate 2000 is removed (desolvent), that is, dried.
Examples of the method for removing the solvent (drying) include methods such as heating, leaving under atmospheric pressure or reduced pressure, and spraying (blowing) an inert gas, etc., but a method using heating is preferred. Thereby, it is possible to remove the solvent relatively easily and in a short time.

  The heating temperature is preferably about 25 to 60 ° C, and more preferably about 30 to 45 ° C.

  The heating time is preferably about 15 to 60 minutes, and more preferably about 15 to 30 minutes.

  As described above, a solidified laminated body 2000 is obtained on the support substrate 1000. Thereby, it is possible to prevent the optical waveguide 90 from being deformed due to a loss of shape in the laminated body 2000 in a later step.

  At this time, the second layer (PITDM dry film) 1120 has a first refractive index (RI). This first refractive index is due to the action of the polymer 915 and the monomer uniformly dispersed (distributed) in the second layer 1120.

[5A] Next, a mask (masking) 935 in which an opening (window) 9351 is formed is prepared, and active radiation (active energy ray) 930 is irradiated to the stacked body 2000 through the mask 935 (FIG. 5).

  In the following, as the core layer forming material, a monomer having a refractive index lower than that of the polymer 915 is used, and a catalyst precursor whose activation temperature decreases with irradiation of the active radiation 930 is used. Will be described as an example.

  That is, in the example shown here, the irradiation region 925 of the active radiation 930 becomes the clad portion 95.

  Therefore, in the example shown here, an opening (window) 9351 equivalent to the pattern of the clad portion 95 to be formed is formed in the mask 935. This opening 9351 forms a transmission part through which the active radiation 930 to be irradiated passes.

  The mask 935 may be formed in advance (separately formed) (for example, plate-shaped) or may be formed on the stacked body 2000 (third layer 1130) by, for example, a vapor deposition method or a coating method. .

  Preferred examples of the mask 935 include a photomask made of quartz glass or a PET base material, a stencil mask, a metal thin film formed by a vapor deposition method (evaporation, sputtering, etc.), etc. Among these, it is particularly preferable to use a photomask or a stencil mask. This is because a fine pattern can be formed with high accuracy, and handling is easy, which is advantageous in improving productivity.

  In FIG. 5, an opening (window) 9351 equivalent to the pattern of the clad portion 95 to be formed is obtained by partially removing the mask along the pattern of the non-irradiated region 940 of the active radiation 930. In the case of using a photomask made of quartz glass, PET base material, or the like, it is also possible to use a photomask provided with a shielding portion of active radiation 930 made of a shielding material made of metal such as chromium. it can. In this mask, the part other than the shielding part is the window (transmission part).

  The actinic radiation 930 to be used is not particularly limited as long as it can cause a photochemical reaction (change) to the promoter. For example, in addition to visible light, ultraviolet light, infrared light, and laser light, an electron beam or X Lines or the like can also be used.

  Among these, the actinic radiation 930 is appropriately selected depending on the type of co-catalyst and the type of sensitizer when it contains a sensitizer, and is not particularly limited, but has a peak wavelength in the range of 200 to 450 nm. It is preferable to have it. Thereby, a cocatalyst can be activated comparatively easily.

The irradiation dose of the actinic radiation 930 is preferably in the range of about 0.1~9J / cm ^2, more preferably about ^{0.2~6J / cm 2, 0.2~3J / cm} 2 of about More preferably. Thereby, a promoter can be activated reliably.

  When the stacked body 2000 is irradiated with the active radiation 930 through the mask 935, the promoter (first substance: cocatalyst) present in the irradiation region 925 irradiated with the active radiation 930 of the second layer 1120 is: It reacts or decomposes by the action of actinic radiation 930 to liberate (generate) cations (protons or other cations) and weakly coordinating anions (WCA).

  These cations and weakly coordinating anions cause a change (decomposition) in the molecular structure of the catalyst precursor (second substance: procatalyst) present in the irradiation region 925, and this changes the active latent state (latent potential). Active state).

  Here, the catalyst precursor in the active latent state (or the latent active state) has an activation temperature lower than the original activation temperature, but there is no temperature increase, that is, at about room temperature, the irradiation region. It refers to a catalyst precursor that is in a state where a monomer reaction cannot occur within 925.

  Therefore, even after irradiation with the active radiation 930, if the laminate 2000 is stored at, for example, about −40 ° C., the state can be maintained without causing a monomer reaction. For this reason, the optical waveguide 90 can be obtained by preparing a plurality of the laminated bodies 2000 after the irradiation with the active radiation 930 and subjecting them to a heat treatment, which is highly convenient.

  Note that in the case where light having high directivity such as laser light is used as the active radiation 930, the use of the mask 935 may be omitted.

[6A] Next, the laminated body 2000 is subjected to a heat treatment (first heat treatment).
Thereby, in the irradiation region 925, the catalyst precursor in the active latent state is activated (becomes active), and monomer reaction (polymerization reaction or cross-linking reaction) occurs.

  As the monomer reaction proceeds, the monomer concentration in the irradiation region 925 gradually decreases. As a result, there is a difference in monomer concentration between the irradiated region 925 and the unirradiated region 940, and the monomer diffuses from the unirradiated region 940 and collects in the irradiated region 925 in order to eliminate this.

  As a result, in the irradiated region 925, the monomer and its reaction product (polymer, cross-linked structure or branched structure) increase, and the structure derived from the monomer greatly affects the refractive index of the region, so that the first refraction The second refractive index lower than the refractive index. As the monomer polymer, an addition (co) polymer is mainly produced.

  On the other hand, in the unirradiated region 940, the amount of monomer decreases due to the diffusion of the monomer from the region to the irradiated region 925, so that the influence of the polymer 915 greatly appears on the refractive index of the region, and the first refraction The third refractive index is higher than the refractive index.

  In this way, a refractive index difference (second refractive index <third refractive index) occurs between the irradiated region 925 and the non-irradiated region 940, and the core portion 94 (non-irradiated region 940) and the cladding portion 95. (Irradiation region 925) is formed (see FIG. 6).

  Although the heating temperature in this heat processing is not specifically limited, It is preferable that it is about 30-80 degreeC, and it is more preferable that it is about 40-60 degreeC.

  The heating time is preferably set so that the reaction of the monomer in the irradiation region 925 is almost completed. Specifically, the heating time is preferably about 0.1 to 2 hours, and 0.1 to 1 hour. More preferred is the degree.

[7A] Next, the laminated body 2000 is subjected to a second heat treatment.
Thereby, the catalyst precursor remaining in the unirradiated region 940 and / or the irradiated region 925 of the second layer 1120 is activated (activated) directly or with activation of the promoter. The monomer remaining in each region 925, 940 is reacted.

  In this way, by reacting the monomer remaining in each of the regions 925 and 940, the core portion 94 and the clad portion 95 obtained can be stabilized.

  The heating temperature in the second heat treatment is not particularly limited as long as it can activate the catalyst precursor or the cocatalyst, but is preferably about 70 to 100 ° C, and is about 80 to 90 ° C. Is more preferable.

  The heating time is preferably about 0.5 to 2 hours, more preferably about 0.5 to 1 hour.

[8A] Next, the laminated body 2000 is subjected to a third heat treatment.
Thereby, the internal stress generated in the obtained core layer 93 can be reduced, and the core portion 94 and the cladding portion 95 can be further stabilized.

  The heating temperature in the third heat treatment is preferably set to 20 ° C. or more higher than the heating temperature in the second heat treatment, specifically, preferably about 90 to 180 ° C., 120 to 160 ° C. More preferred is the degree.

  The heating time is preferably about 0.5 to 2 hours, more preferably about 0.5 to 1 hour.

  Through the above steps, the core layer 93 and the clad layers 91 and 92 are formed, and the optical waveguide 90 is obtained.

  For example, when a sufficient refractive index difference is obtained between the core portion 94 and the clad portion 95 in a state before the second heat treatment or the third heat treatment is performed, this step is performed. [8A] and the step [7A] may be omitted.

  As described above, in the present invention, the non-solidified or uncured layers 1110, 1120, and 1130 are stacked, and the processing for forming the core portion 94 is performed on the stacked body 2000 to obtain the optical waveguide 90. Therefore, these constituent materials are mixed with each other at the interface between the first layer 1110 and the second layer 1120 and the interface between the second layer 1120 and the third layer 1130. Thereby, in the obtained optical waveguide 90, the adhesion between the clad layer 91 and the core layer 93 and the adhesion between the core layer 93 and the clad layer 92 can be improved. As a result, separation at the interface of each layer can be prevented and the optical transmission performance of the optical waveguide 90 can be improved.

  As the first varnish and the third varnish, the same composition as that of the second varnish, that is, one containing a polymer 915, a monomer, a promoter and a catalyst precursor may be used. Accordingly, the monomer reaction causes the interface between the first layer 1110 and the third layer 1130 and the second layer 1120, and / or beyond the interface, in the first layer 1110 and the third layer 1130. And the peeling between the clad layers 91 and 92 and the core layer 93 can be prevented more reliably.

  In this case, for example, I: As the polymer 915 of the first layer 1110 and the third layer 1130, one having a refractive index (RI) relatively lower than the refractive index of the polymer 915 of the second layer 1120 is selected. II: The same monomer as that of the second layer 1120 is used as the monomer of the first layer 1110 and the third layer 1130, but the catalyst precursor and the monomer in the first layer 1110 and the third layer 1130 are used. The ratio may be adjusted to be lower than that of the second layer 1120.

  Accordingly, even when the active radiation 930 is irradiated, it is possible to prevent the formation of a region having a refractive index higher than that of the core portion 94 of the core layer 93 in the cladding layers 91 and 92.

  In this case, a promoter that is not activated when the core layer 93 (core portion 94) is formed may be selected. For example, a cocatalyst that does not absorb actinic radiation suitable for activating the cocatalyst contained in the second varnish or is activated by the action of heat in place of the actinic radiation may be selected.

  Examples of such a co-catalyst include a non-absorbing photobase generator (PBG) and a thermal base generator (TBG).

[9A] Next, conductor layers 901 and 902 are formed on the upper and lower surfaces of the optical waveguide 90, respectively (see FIG. 7).

As a method for forming each of the conductor layers 901 and 902, for example, a chemical vapor deposition method (CVD method) such as a plasma CVD method, a thermal CVD method, or a laser CVD method, a vacuum deposition method, a sputtering method, or an ion is used. Among the bonding of conductive sheet materials by dry plating methods such as physical vapor deposition methods (PVD methods) such as plating methods, wet plating methods such as electrolytic plating, immersion plating and electroless plating, and laminating methods At least one of the following can be used. Thereby, high adhesiveness between each of the conductor layers 901 and 902 and the optical waveguide 90 is obtained.
As described above, the optical waveguide structure 9 of the present invention is completed.

  In such a method, the core portion 94 can be visually confirmed in the stacked body 2000 after the first heat treatment.

  In a preferable example of such an optical waveguide structure 9, in the core layer 93, the core portion 94 is configured using the first norbornene-based material as a main material, and the cladding portion 95 has a lower refractive index than that of the first norbornene-based material. The second norbornene-based material is used as a main material, and the cladding layers 91 and 92 each have a lower refractive index than the first norbornene-based material, and the third norbornene-based material containing the norbornene-based polymer is used as the main material. Configured as

  The first norbornene-based material and the second norbornene-based material both contain the same norbornene-based polymer, but contain a reaction product of a norbornene-based monomer having a refractive index different from that of the norbornene-based polymer. Due to the different amounts, the refractive indices are different from each other.

  Since the norbornene-based polymer has high transparency, the optical waveguide structure 9 having such a configuration can provide high optical transmission performance of the optical waveguide 90.

  Further, with such a configuration, not only high adhesion between the core portion 94 and the clad portion 95 but also high adhesion between the core layer 93, the clad layer 91, and the clad layer 92 can be obtained. Even when deformation such as bending occurs in the structure 9, peeling between the core portion 94 and the clad portion 95 and delamination between the core layer 93 and the clad layers 91 and 92 do not easily occur. It is also possible to prevent micro cracks from occurring in 95. As a result, the optical transmission performance of the optical waveguide 90 is maintained.

  Furthermore, since the norbornene-based polymer has high heat resistance and high hydrophobicity, the optical waveguide 90 (optical waveguide structure 9) having such a configuration has excellent durability.

  In addition, since high heat resistance and high hydrophobicity can be imparted to the optical waveguide 90, the conductor layers 901 and 902 can be formed by adopting various methods as described above while preventing deterioration (deterioration) of the characteristics. It can be reliably formed. In particular, even when the conductor layers 901 and 902 are formed so as to overlap with the core portion 94 important for light transmission, the core portion 94 can be prevented from being deteriorated or deteriorated.

  Further, according to the manufacturing method as described above, the optical waveguide structure 9 having the core portion 94 having a desired shape and high dimensional accuracy can be obtained by a simple process and in a short time. .

<Second production method>
Next, a second manufacturing method of the optical waveguide structure 9 will be described.

  Hereinafter, the second manufacturing method will be described, but the description will focus on differences from the first manufacturing method, and description of similar matters will be omitted.

  In the second manufacturing method, the composition of the core layer forming material is different, and other than that is the same as the first manufacturing method.

  That is, the core layer-forming material used in the second production method comprises a release agent (substance) that is activated by irradiation with actinic radiation, and a main chain and a release agent that is branched from the main chain and activated. And at least a part of the molecular structure contains a polymer 915 having a detachable group (detachable pendant group) that can detach from the main chain.

As the releasing agent, the same promoter as that mentioned in the first production method can be used.
Examples of the polymer 915 used in the second production method include those obtained by substituting the substituents of the polymer 915 exemplified in the first production method with a leaving group, and polymers 915 exemplified in the first production method. The thing which introduce | transduced the leaving group is mentioned.

  The refractive index of the polymer 915 changes (increases or decreases) due to the leaving (cleavage) of the leaving group.

  The leaving group may be any of those leaving by the action of a cation, anion or free radical, that is, any of an acid (cation) leaving group, a base (anion) leaving group, and a free radical leaving group. Although it is good, it is preferably a group capable of leaving by the action of a cation (proton) (acid group leaving group).

  As the acid leaving group, those having at least one of an —O— structure, an —Si—aryl structure and an —O—Si— structure in its molecular structure are preferable. Such an acid leaving group is released relatively easily by the action of a cation.

  Among these, as the acid leaving group that causes a decrease in the refractive index of the polymer 915 by leaving, at least one of a -Si-diphenyl structure and a -O-Si-diphenyl structure is preferable.

  In addition, as a free radical leaving group which leaves | separates by the effect | action of a free radical, the substituent etc. which have an acetophenone structure at the terminal are mentioned, for example.

  The polymer 915 is preferably a norbornene polymer for the same reason as described in the first production method, and more preferably a norbornene polymer containing a repeating unit of alkyl (particularly hexyl) norbornene. preferable.

  In consideration of the above, as the polymer 915 whose refractive index decreases due to the leaving group leaving, a homopolymer of diphenylmethylnorbornenemethoxysilane or a copolymer of hexylnorbornene and diphenylmethylnorbornenemethoxysilane is preferably used. .

  Hereinafter, as an example, a case in which a material whose refractive index is reduced by the removal of a leaving group (particularly, an acid leaving group) is used as the polymer 915 in the core layer forming material will be described.

  That is, in the example shown here, the irradiation region 925 of the active radiation 930 becomes the clad portion 95.

[1B] A step similar to the step [1A] is performed.
[2B] A step similar to the step [2A] is performed.
[3B] A step similar to the step [3A] is performed.
[4B] A step similar to the step [4A] is performed.

  At this time, the second layer (PITDM dry film) 1120 has a first refractive index (RI). This first refractive index is due to the action of the polymer 915 that is uniformly dispersed (distributed) in the second layer 1120.

[5B] A step similar to the step [5A] is performed.
When the active body 930 is irradiated with the active radiation 930 through the mask 935, the release agent present in the irradiation region 925 irradiated with the active radiation 930 of the second layer 1120 reacts (bonds) by the action of the active radiation 930. ) Or decompose to liberate (generate) cations (protons or other cations) and weakly coordinating anions (WCA).

  Then, the cation causes the leaving group itself to leave the main chain, or cleaves from the middle of the molecular structure of the leaving group (photo bleach).

  As a result, in the irradiated region 925, the number of leaving groups in a complete state is decreased as compared with the unirradiated region 940, and the second refractive index is lower than the first refractive index. At this time, the refractive index of the unirradiated region 940 is maintained at the first refractive index.

  In this way, a refractive index difference (second refractive index <first refractive index) occurs between the irradiated region 925 and the non-irradiated region 940, and the core portion 94 (non-irradiated region 940) and the cladding portion 95. (Irradiation region 925) is formed.

In this case, the irradiation dose of the actinic radiation 930 is preferably in the range of about 0.1~9J / cm ^2, more preferably about 0.3~6J / cm ^2, 0.6~6J / More preferably, it is about cm ² . Thereby, a release agent can be activated reliably.

[6B] Next, the laminated body 2000 is subjected to heat treatment.
As a result, the leaving group detached (cut) from the polymer 915 is removed from the irradiated region 925 or rearranged or cross-linked in the polymer 915.

  Further, at this time, it is considered that a part of the leaving group remaining in the cladding part 95 (irradiation region 925) is further detached (cut).

  Therefore, the refractive index difference between the core portion 94 and the cladding portion 95 can be further increased by performing such heat treatment.

  The heating temperature in this heat treatment is not particularly limited, but is preferably about 70 to 195 ° C, and more preferably about 85 to 150 ° C.

  Further, the heating time is set so as to sufficiently remove the leaving group detached (cut) from the irradiation region 925, and is not particularly limited, but is preferably about 0.5 to 3 hours, More preferably, it is about 2 hours.

  For example, when a sufficient refractive index difference is obtained between the core portion 94 and the cladding portion 95 in a state before the heat treatment, this step [6B] may be omitted. .

  Moreover, the process of 1 time or several times of heat processing (for example, about 150-200 degreeC x about 1 to 8 hours) can also be added as needed.

  Through the above steps, the core layer 93 and the clad layers 91 and 92 are formed, and the optical waveguide 90 is obtained.

  When the second production method is used, the cladding layer forming material (first varnish, third varnish) is prepared using a polymer 915 that does not have a leaving group, or is detached. A polymer 915 having a functional group is used, but it is preferable to use a polymer that does not contain a release agent.

  Accordingly, even when the active radiation 930 is irradiated, it is possible to prevent the formation of a region having a refractive index higher than that of the core portion 94 of the core layer 93 in the cladding layers 91 and 92.

[7B] A step similar to the step [9A] is performed.
As described above, the optical waveguide structure 9 of the present invention is completed.

  In a preferred example of such an optical waveguide structure 9, the core layer 93 is composed of a norbornene-based material as a main material, and the cladding layers 91 and 92 each have a lower refractive index than the core portion 94 of the core layer 93, and norbornene The main material is a norbornene-based material containing a polymer.

  The core portion 94 and the clad portion 95 are mainly composed of a norbornene-based polymer having a main chain and a main chain branched from the main chain and having a leaving group capable of leaving at least a part of the molecular structure from the main chain. The core part 94 and the clad part 95 have different refractive indexes due to the difference in the number of leaving groups bonded to the main chain.

  Since the norbornene-based polymer has high transparency, the optical waveguide structure 9 having such a configuration can provide high optical transmission performance of the optical waveguide 90.

  Further, with such a configuration, not only high adhesion between the core portion 94 and the clad portion 95 but also high adhesion between the core layer 93, the clad layer 91, and the clad layer 92 can be obtained. Even when deformation such as bending occurs in the structure 9, peeling between the core portion 94 and the clad portion 95 and delamination between the core layer 93 and the clad layers 91 and 92 do not easily occur. It is also possible to prevent micro cracks from occurring in 95. As a result, the optical transmission performance of the optical waveguide 90 is maintained.

  Furthermore, since the norbornene-based polymer has high heat resistance and high hydrophobicity, the optical waveguide 90 (optical waveguide structure 9) having such a configuration has excellent durability.

  In addition, since high heat resistance and high hydrophobicity can be imparted to the optical waveguide 90, the conductor layers 901 and 902 can be formed by adopting various methods as described above while preventing deterioration (deterioration) of the characteristics. It can be reliably formed. In particular, even when the conductor layers 901 and 902 are formed so as to overlap with the core portion 94 important for light transmission, the core portion 94 can be prevented from being deteriorated or deteriorated.

  Further, according to the manufacturing method as described above, the optical waveguide structure 9 having the core portion 94 having a desired shape and high dimensional accuracy can be obtained by a simple process and in a short time. .

  In particular, according to the second manufacturing method, at least actinic radiation may be used, and the core layer 93 can be formed by an extremely simple process.

<Third production method>
Next, the 3rd manufacturing method of the optical waveguide structure 9 is demonstrated.

  Hereinafter, the third manufacturing method will be described, but the description will focus on differences from the first and second manufacturing methods, and the description of the same matters will be omitted.

  In the third manufacturing method, a combination of the core layer forming materials used in the first and second manufacturing methods is used as the core layer forming material. Otherwise, the first or second manufacturing method is used. It is the same.

  That is, the core layer forming material used in the third manufacturing method includes the polymer 915 having a leaving group as described above, a monomer, a promoter (first substance), and a catalyst precursor (second Substance). The cocatalyst is the same as the release agent in the second production method, and has a function of releasing the release agent.

  In such a core layer forming material, the refractive index difference between the core portion 94 and the clad portion 95 in the core layer 93 obtained by the combination of the leaving group to be selected and the monomer to be selected is further increased. It becomes possible to adjust to.

  As described above, a monomer having a refractive index lower than that of the polymer 915 is used as a monomer, and a catalyst precursor whose activation temperature is reduced with irradiation of the active radiation 930 is used as a polymer 915. If a material whose refractive index is lowered by the removal of the leaving group is used, the irradiation region 925 can be used as the cladding portion 95, and the core layer 93 having a very large refractive index difference from the core portion 94 can be obtained.

  Hereinafter, the case where such a combination of polymer 915, monomer, and catalyst precursor is used in the core layer forming material will be described as an example.

  That is, in the example shown here, the irradiation region 925 of the active radiation 930 becomes the clad portion 95.

[1C] A step similar to the step [1A] is performed.
[2C] A step similar to the step [2A] is performed.
[3C] The same step as the above step [3A] is performed.
[4C] A step similar to the step [4A] is performed.

  At this time, the second layer (PITDM dry film) 1120 has a first refractive index (RI). This first refractive index is due to the action of the polymer 915 and the monomer uniformly dispersed (distributed) in the second layer 1120.

[5C] The same step as the above step [5A] is performed.
When the active body 930 is irradiated with the active radiation 930 through the mask 935, the promoter (first substance: cocatalyst) present in the irradiation region 925 irradiated with the active radiation 930 of the first layer 1120 is It reacts or decomposes by the action of actinic radiation 930 to liberate (generate) cations (protons or other cations) and weakly coordinating anions (WCA).

  These cations and weakly coordinating anions cause a change (decomposition) in the molecular structure of the catalyst precursor (second substance: procatalyst) present in the irradiation region 925, and this changes the active latent state (latent potential). Active state).

  In addition, the cation causes the leaving group itself to leave the main chain, or cleaves from the middle of the molecular structure of the leaving group.

  As a result, in the irradiated region 925, the number of leaving groups in a complete state is reduced as compared with the unirradiated region 940, and the refractive index is lowered to be lower than the first refractive index. At this time, the refractive index of the unirradiated region 940 is maintained at the first refractive index.

In this case, the irradiation dose of the actinic radiation 930 is preferably in the range of about 0.1~9J / cm ^2, more preferably about 0.2~5J / cm ^2, 0.2~4J / More preferably, it is about cm ² . Thereby, a promoter can be activated reliably.

[6C] The same step as the above step [6A] is performed.
Thereby, in the irradiation region 925, the catalyst precursor in the active latent state is activated (becomes active), and monomer reaction (polymerization reaction or cross-linking reaction) occurs.

  As the monomer reaction proceeds, the monomer concentration in the irradiation region 925 gradually decreases. As a result, there is a difference in monomer concentration between the irradiated region 925 and the unirradiated region 940, and the monomer diffuses from the unirradiated region 940 and collects in the irradiated region 925 in order to eliminate this.

  In addition, by this heat treatment, the leaving group detached (cut) from the polymer 915 is removed from, for example, the irradiation region 925, or rearranged or crosslinked in the polymer 915.

  As a result, in the irradiated region 925, the monomer and its reactant (polymer, cross-linked structure and branched structure) increase, and the structure derived from the monomer greatly affects the refractive index of the region. The refractive index is further lowered to the second refractive index due to a decrease in the leaving (cleaved) leaving group.

  On the other hand, in the unirradiated region 940, the amount of monomer decreases due to the diffusion of the monomer from the region to the irradiated region 925, so that the influence of the polymer 915 greatly appears on the refractive index of the region, and the first refraction The third refractive index is higher than the refractive index.

  In this way, a refractive index difference (second refractive index <third refractive index) occurs between the irradiated region 925 and the non-irradiated region 940, and the core portion 94 (non-irradiated region 940) and the cladding portion 95. (Irradiation region 925) is formed.

[7C] The same step as the above step [7A] is performed.
[8C] The same step as the above step [8A] is performed.
[9C] The same step as the above step [9A] is performed.

As described above, the optical waveguide structure 9 of the present invention is completed.
In a preferred example of such an optical waveguide structure 9, the core layer 93 is a norbornene polymer having a main chain and a leaving group that is branched from the main chain and at least a part of the molecular structure can be detached from the main chain. The core portion 94 and the clad portion 95 are different in the number of leaving groups bonded to the main chain and the reaction product of a norbornene monomer having a refractive index different from that of the norbornene polymer. Due to the different contents, their refractive indexes are different, and the cladding layers 91 and 92 are each composed mainly of a norbornene-based material containing a norbornene-based polymer.

  Since the norbornene-based polymer has high transparency, the optical waveguide structure 9 having such a configuration can provide high optical transmission performance of the optical waveguide 90.

  Further, with such a configuration, not only high adhesion between the core portion 94 and the clad portion 95 but also high adhesion between the core layer 93, the clad layer 91, and the clad layer 92 can be obtained. Even when deformation such as bending occurs in the structure 9, peeling between the core portion 94 and the clad portion 95 and delamination between the core layer 93 and the clad layers 91 and 92 do not easily occur. It is also possible to prevent micro cracks from occurring in 95. As a result, the optical transmission performance of the optical waveguide 90 is maintained.

  Furthermore, since the norbornene-based polymer has high heat resistance and high hydrophobicity, the optical waveguide 90 (optical waveguide structure 9) having such a configuration has excellent durability.

  In addition, since high heat resistance and high hydrophobicity can be imparted to the optical waveguide 90, the conductor layers 901 and 902 can be formed by adopting various methods as described above while preventing deterioration (deterioration) of the characteristics. It can be reliably formed. In particular, even when the conductor layers 901 and 902 are formed so as to overlap with the core portion 94 important for light transmission, the core portion 94 can be prevented from being deteriorated or deteriorated.

  Further, according to the manufacturing method as described above, the optical waveguide structure 9 having the core portion 94 having a desired shape and high dimensional accuracy can be obtained by a simple process and in a short time. .

  In particular, according to the third manufacturing method, the refractive index difference between the core portion 94 and the cladding portion 95 can be set in multiple stages.

  Further, in each of the first to third manufacturing methods, it has been described that the support substrate 1000 is removed. You may do it.

  Moreover, you may abbreviate | omit either one or both of the clad layers 91 and 92 as needed.

  Further, the optical waveguide 90 is not limited to the configuration shown in the figure. For example, the optical waveguide 90 may have a configuration in which a plurality of core layers are provided between two cladding layers. May be laminated in order, or a laminated body in which a single core layer is provided between two clad layers may be laminated.

  In addition, an inclined surface (reflecting surface) inclined by approximately 45 ° with respect to the optical path, that is, the longitudinal direction of the core portion 94 may be formed in the middle of the core portion 94. Thereby, the light (transmission light) propagating through the core portion 94 can be bent by approximately 90 ° on this inclined surface.

  Then, by appropriately setting the direction of the inclined surface, the optical path of the transmitted light is changed not only in the core layer 90 (two-dimensional direction) but also in a three-dimensional direction including the thickness direction of the optical waveguide 90. Is possible.

  This inclined surface can be formed by, for example, cutting or removing (deleting) the core portion 94. A reflective film such as a multilayer optical thin film or a metal thin film (for example, an aluminum vapor deposition film) or a reflection increasing film may be formed on the inclined surface.

  The optical waveguide manufacturing method, the optical waveguide, and the optical waveguide structure according to the present invention have been described based on the illustrated embodiments. However, the present invention is not limited to these, and the configuration of each part is the same. It can be replaced with an arbitrary configuration that can exhibit the function, and an arbitrary configuration may be added.

Hereinafter, specific examples of the present invention will be described.
1. Synthesis of Catalyst Precursor << Catalyst Precursor C1: Synthesis of Pd (OAc) ₂ (P (i-Pr) ₃ ) ₂ >>
To a nitrogen-filled flask equipped with a funnel, a CH ₂ Cl ₂ solution (20 mL) of P (i-Pr) ₃ (8.51 mL (44.6 mmol)) was added to Pd (OAc) ₂ (5.00 g, 22.3 mmol). ) And CH ₂ Cl ₂ (30 mL) was added dropwise to a stirred red-brown suspension at −78 ° C.

  The suspension gradually passed through a yellowish green solution, then warmed to room temperature and stirred for 2 hours. Then, it filtered with the 0.45 micrometer filter.

The filtrate was concentrated to 10 mL and hexane (20 mL) was added to give a yellow solid.
This was filtered (in air), washed with hexane (5 × 5 mL) and vacuum dried.

The yield was 10.937 g (89%). The NMR data was as follows. ¹ H-NMR (δ, CD ₂ Cl ₂ ): 1.37 (dd, 36H, CHCH ₃ ), 1.77 (s, 6H, CCH ₃ ), 2.12 (m, 6H, CH), ³¹ P _{-NMR (δ, CD 2 Cl 2} ): 32.9 (s).

<< Catalyst Precursor C2: Synthesis of Pd (OAc) ₂ (P (Cy) ₃ ) ₂ >>
In a 2-neck round bottom flask equipped with a funnel, a reddish brown suspension consisting of Pd (OAc) ₂ (5.00 g, 22.3 mmol) and CH ₂ Cl ₂ (30 mL) was stirred at −78 ° C.

A funnel was charged with a solution of P (Cy) ₃ (13.12 mL (44.6 mmol)) in CH ₂ Cl ₂ (30 mL) and added dropwise to the stirred suspension over 15 minutes. As a result, the color gradually changed from reddish brown to yellow.

  After stirring at −78 ° C. for 1 hour, the suspension was warmed to room temperature, stirred for an additional 2 hours, and diluted with hexane (20 mL).

The yellow solid was then filtered in air, washed with pentane (5 × 10 mL) and dried in vacuo.
The secondary collection was separated by cooling the filtrate to 0 ° C., washed and dried as above.

The yield was 15.42 g (88%). The NMR data was as follows. ¹ H-NMR (δ, CD ₂ Cl ₂ ): 1.18-1.32 (brm, 18H, Cy), 1.69 (brm, 18H, Cy), 1.80 (brm, 18H, Cy), 1.84 (s, 6H, CH ₃ ), 2.00 (br d, 12H, Cy), ³¹ P-NMR (δ, CD ₂ Cl ₂ ): 21.2 (s).

<< catalyst precursor _{C3: trans-Pd (O 2} C-t-Bu) 2 (P (Cy) 3) 2 Synthesis >>
Pd (O ₂ Ct-Bu) ₂ (1.3088 g, 4.2404 mmol) was dispersed in CH ₂ Cl ₂ (10 mL) in a Schlenker flask and the flask contents were cooled to −78 ° C. and allowed to stir. It was.

To this solution was added a solution of P (Cy) ₃ (2.6749 g, 9.5382 mmol) in CH ₂ Cl ₂ (15 mL) and stirred at −78 ° C. for 1 hour and at room temperature for 2 hours.

  Hexane (20 mL) was added to the reaction mixture to give the title yellow solid complex (1.391 g).

The solid was filtered, washed with hexane (10 mL) and dried under reduced pressure.
Solvent was removed from the filtrate to give an orange solid which was then dissolved in a CHCl ₃ / hexane mixture (1/1: v / v) and the resulting solution was evaporated in a fume hood. The indicated complex was further obtained (648 mg).

The overall yield was 2.039 g (2.345 mmol, 55.3%).
When calculated as C ₄₆ H ₈₄ O ₄ P ₂ Pd, C is 63.54% and H is 9.74%.

<< Catalyst Precursor C4: Synthesis of Pd (OAc) ₂ (P (Cp) ₃ ) ₂ >>
A red-brown suspension of Pd (OAc) ₂ (2.00 g, 8.91 mmol) in CH ₂ Cl ₂ (˜25 mL) was stirred at −78 ° C. in a nitrogen-filled flask.

With a cannula, P (Cp) ₃ (4.25 g, 17.83 mmol) was dissolved in CH ₂ Cl ₂ (˜20 mL) and added dropwise to the suspension over 10 minutes. As a result, the color gradually changed from reddish brown to yellow.

  The suspension was warmed to room temperature and stirred for an additional hour. The solvent was concentrated (˜5 mL) and hexane (˜15 mL) was added to give a yellow solid.

  It was filtered in air, washed with hexane (5 × 10 mL) and dried in vacuo. The secondary collection was separated by cooling the filtrate to 0 ° C., filtered, washed and dried in the same manner as catalyst precursor C3.

The yield was 4.88 g (85%). The NMR data was as follows. ¹ H-NMR (δ, CD ₂ Cl ₂ ): 1.52-1.56 (brm, 12H, Cp ₃ ), 1.67-1.72 (brm, 12H, Cp ₃ ), 1.74 _{(s, 6H, CH 3)} , 1.85-1.89 (br m, 12H, Cp 3), 1.96-1.99 (br d, 6H, Cp 3), 2.03-2.09 _{(br m, 12H, Cp 3} ). ³¹ P-NMR (δ, CD ₂ Cl ₂ ): 22.4 (s).

2. Synthesis of Polymer (Polymer Matrix) Each polymer P5, 6, 8, 9, 12, 13, 14 was synthesized as follows.

  In the following, hexyl norbornene (CAS number 22094-83-3) is “HxNB”, diphenylmethylnorbornene methoxysilane (CAS number 376634-34-3) is “diPhNB”, phenylethyl norbornene ( CAS number 29415-09-6) is “PENB”, butylnorbornene (CAS number 22094-81-1) is “BuNB”, and decylnorbornene (CAS number 22094-85-5) is “ DeNB ", benzylnorbornene (CAS number 2665989-73-9)" BzNB ", methylglycidyl ether norbornene (CAS number 3188-75-8)" AGENB ", norbornenylethyltrimethoxy Silane (CAS No. 68245-19- No.) "TMSENB", triethoxysilyl norbornene (CAS number 18401-43-9) "TESNB", trimethoxysilyl norbornene (CAS number 7538-46-7) "TMSNB", Each may be abbreviated.

<< Polymer P5: Synthesis of hexylnorbornene (HxNB) / diphenylmethylnorbornene methoxysilane copolymer (diPhNB) >>
HxNB (8.94 g, 0.050 mol), diPhNB (16.06 g, 0.050 mol), 1-hexene (5.0 g, 0.060 mol) and toluene (142 g) were mixed in a 500 mL sealam bottle and oil A solution was formed by heating to 80 ° C. in a bath.

To this solution, Pd1446 (2.90 × 10 ⁻³ g, 2.00 × 10 ⁻⁶ mol) and DANFABA (3.2 × 10 ⁻³ g, 4.01 × 10 ⁻⁶ mol) were concentrated in dichloromethane. Added in the form of a solution.

  After the addition, the resulting solution was maintained at 80 ° C. for 6 hours. When methanol was added dropwise to the vigorously stirred mixture, the copolymer precipitated.

  The precipitated copolymer was collected by filtration and dried in an oven at 60 ° C. under vacuum. The weight after drying was 19.3 g (yield: 77%).

  When the molecular weight of the copolymer was measured by GPC method using THF as a solvent (polystyrene standard), it was Mw = 58,749 and Mn = 18,177.

When the composition of the copolymer was measured by ¹ H-NMR, it was ¹ H-NMR: 53/47 = HxNB / diPhNB copolymer.

  When the refractive index of this copolymer was measured by the prism coupling method, it was 1.5572 in the TE mode and 1.5558 in the TM mode at a wavelength of 633 nm.

<< Polymer P6: Synthesis of Butylnorbornene (BuNB) / Diphenylmethylnorbornenemethoxysilane (diPhNB) Copolymer >>
BuNB (2.62 g, 0.017 mol), diPhNB (22.38 g, 0.07 mol), 1-hexene (8.83 g, 0.011 mol) and toluene (141.4 g) were mixed in a 500 mL sealam bottle. And heated to 80 ° C. in an oil bath to form a solution.

To this solution, Pd1446 (5.05 × 10 ⁻³ g, 3.49 × 10 ⁻⁶ mol) and DANFABA (1.12 × 10 ⁻² g, 1.40 × 10 ⁻⁵ mol) were concentrated in dichloromethane. Added in the form of a solution.

  After the addition, the resulting solution was maintained at 80 ° C. for 2 hours. When methanol was added dropwise to the vigorously stirred mixture, the copolymer precipitated.

  The precipitated copolymer was collected by filtration and dried in an oven at 60 ° C. under vacuum. The weight after drying was 7.5 g (yield: 30%).

  When the molecular weight of the copolymer was measured by GPC method using THF as a solvent (polystyrene standard), it was Mw = 32,665 and Mn = 19,705.

When the composition of the copolymer was measured by ¹ H-NMR, it was ¹ H-NMR: 28/72 = BuNB / diPhNB copolymer.

  When the refractive index of this copolymer was measured by the prism coupling method, it was 1.5785 in the TE mode and 1.5771 in the TM mode at a wavelength of 633 nm.

<< Polymer P8: Synthesis of Hexylnorbornene (HxNB) Homopolymer >>
HxNB (10.0 g, 0.056 mol), 1-hexene (4.71 g, 0.056 mol) and toluene (56.7 g) were mixed in a 250 mL sealam bottle and heated to 80 ° C. in an oil bath. A solution was formed.

To this solution, Pd1446 (4.10 × 10 ⁻⁴ g, 2.80 × 10 ⁻⁷ mol) and DANFABA (2.20 × 10 ⁻⁴ g, 2.80 × 10 ⁻⁷ mol) were concentrated in dichloromethane. Added in the form of a solution.

  After the addition, the resulting solution was maintained at 80 ° C. for 40 minutes. When methanol was added dropwise to the vigorously stirred mixture, the polymer precipitated.

  The precipitated polymer was collected by filtration and dried in an oven at 60 ° C. under vacuum. The weight after drying was 5.8 g (yield: 58%).

  When the molecular weight of the polymer was measured by GPC method using THF as a solvent (polystyrene standard), it was Mw = 121,541 and Mn = 59,213.

When the refractive index of this polymer was measured by the prism coupling method, it was 1.5146 in the TE mode and 1.5129 in the TM mode at a wavelength of 633 nm.
Tg based on thermomechanical analysis (TMA) of the polymer was 208 ° C.

<< Polymer P9: Synthesis of hexylnorbornene (HxNB) / diphenylmethylnorbornenemethoxysilane (diPhNB) copolymer >>
HxNB (9.63 g, 0.054 mol), diPhNB (40.37 g, 0.126 mol), 1-hexene (4.54 g, 0.054 mol) and toluene (333 g) were mixed in a 500 mL sealum bottle, A solution was formed by heating to 80 ° C. in an oil bath.

To this solution, Pd1446 (1.04 × 10 ⁻² g, 7.20 × 10 ⁻⁶ mol) and DANFABA (2.30 × 10 ⁻² g, 2.88 × 10 ⁻⁵ mol) were concentrated in dichloromethane. Added in the form of a solution.

  After the addition, the resulting solution was maintained at 80 ° C. for 2 hours. When methanol was added dropwise to the vigorously stirred mixture, the copolymer precipitated.

  The precipitated copolymer was collected by filtration and dried in an oven at 60 ° C. under vacuum. The weight after drying was 19.0 g (yield: 38%).

  When the molecular weight of the copolymer was measured by GPC method using THF as a solvent (polystyrene conversion), it was Mw = 118,000 and Mn = 60,000.

When the composition of the copolymer was measured by ¹ H-NMR, it was ¹ H-NMR: 32/68 = HxNB / diPhNB copolymer.

  When the refractive index of this copolymer was measured by the prism coupling method, it was 1.5695 in TE mode and 1.5681 in TM mode at a wavelength of 633 nm.

<< Polymer P12: Synthesis of hexylnorbornene (HxNB) / diphenylmethylnorbornenemethoxysilane (diPhNB) copolymer >>
HxNB (10.72 g, 0.06 mol), diPhNB (19.28 g, 0.06 mol), 1-hexene (3.5 g, 0.04 mol) and toluene (170.0 g) were mixed in a 250 mL sealam bottle. And heated to 80 ° C. in an oil bath to form a solution.

To this solution, Pd1446 (7.0 × 10 ⁻³ g, 4.8 × 10 ⁻⁶ mol) and DANFABA (3.9 × 10 ⁻³ g, 4.8 × 10 ⁻⁶ mol) were concentrated in dichloromethane. Added in the form of a solution.

  After the addition, the resulting solution was maintained at 80 ° C. for 3.5 hours. When methanol was added dropwise to the vigorously stirred mixture, the copolymer precipitated.

  The precipitated copolymer was collected by filtration and dried in an oven at 60 ° C. under vacuum. The weight after drying was 18.6 g (yield: 62%).

  When the molecular weight of the copolymer was measured by GPC method using THF as a solvent (polystyrene conversion), it was Mw = 102,000 and Mn = 38,000.

When the composition of the copolymer was measured by ¹ H-NMR, it was ¹ H-NMR: 54/46 = HxNB / diPhNB copolymer.

<< Polymer P13: Synthesis of Butylnorbornene (BuNB) / Diphenylmethylnorbornenemethoxysilane (diPhNB) Copolymer >>
BuNB (2.62 g, 0.038 mol), diPhNB (22.38 g, 0.057 mol), 1-hexene (8.83 g, 0.011 mol) and toluene (141.4 g) were mixed in a 500 mL sealam bottle. And heated to 80 ° C. in an oil bath to form a solution.

To this solution, Pd1446 (5.05 × 10 ⁻³ g, 3.49 × 10 ⁻⁶ mol) and DANFABA (1.12 × 10 ⁻² g, 1.40 × 10 ⁻⁵ mol) were concentrated in dichloromethane. Added in the form of a solution.

  After the addition, the resulting solution was maintained at 80 ° C. for 2 hours. When methanol was added dropwise to the vigorously stirred mixture, the copolymer precipitated.

  The precipitated copolymer was collected by filtration and vacuum dried in an oven at 60 ° C. The weight after drying was 7.5 g (yield: 30%).

  When the molecular weight of the copolymer was measured by GPC method using THF as a solvent (polystyrene conversion), it was Mw = 32,665 and Mn = 19,705.

When the composition of the copolymer was measured by ¹ H-NMR, it was ¹ H-NMR: 28/72 = BuNB / diPhNB copolymer.

  When the refractive index of this copolymer was measured by the prism coupling method, it was 1.5785 in the TE mode and 1.5771 in the TM mode at a wavelength of 633 nm.

<< Polymer 14: Synthesis of hexylnorbornene (HxNB) / diphenylmethylnorbornenemethoxysilane (diPhNB) copolymer >>
HxNB (9.63 g, 0.054 mol), diPhNB (1.92 g, 0.006 mol), 1-hexene (5.04 g, 0.060 mol) and toluene (56.7 g) were mixed in a 250 mL sealam bottle. And heated to 80 ° C. in an oil bath to form a solution.

To this solution, Pd1446 (4.30 × 10 ⁻⁴ g, 3.00 × 10 ⁻⁷ mol) and DANFABA (2.40 × 10 ⁻⁴ g, 3.00 × 10 ⁻⁷ mol) were concentrated in dichloromethane. Added in the form of a solution.

  After the addition, the resulting solution was maintained at 80 ° C. for 2 hours. When methanol was added dropwise to the vigorously stirred mixture, the copolymer precipitated.

  The precipitated copolymer was collected by filtration and vacuum dried in an oven at 60 ° C. The weight after drying was 7.7 g (yield: 67%).

  When the molecular weight of the copolymer was measured by GPC method using THF as a solvent (in terms of polystyrene), it was Mw = 82,000 and Mn = 40,000.

When the composition of the copolymer was measured by ¹ H-NMR, it was ¹ H-NMR: 89/11 = HxNB / diPhNB copolymer.

When the refractive index of this copolymer was measured by the prism coupling method, it was 1.5238 in the TE mode and 1.5225 in the TM mode at a wavelength of 633 nm.
Each polymer synthesized above is summarized in Table 1 below.

3. Preparation of varnish Each varnish V8-13 was prepared as follows. Each varnish was prepared under a yellow light because it contained a photosensitive material.

  Hereinafter, dimethylbis (norbornenemethoxy) silane (CAS No. 376609-87-9) may be abbreviated as “SiX”.

<< Preparation of Varnish V8 >>
HxNB (42.03 g, 0.24 mol) and SiX (7.97 g, 0.026 mol) were weighed and placed in a glass bottle.

  To this monomer solution, IRGANOX 1076 (0.5 g) and IRGAFOS 168 (0.125 g) were added as antioxidants to obtain a monomer antioxidant solution.

In a solution (18.3 g) of the above polymer P5 dissolved in mesitylene so as to be 10 wt%, a monomer antioxidant solution (3.06 g) and Pd785 (3.85 × 10 ⁻⁴ g, 4.91 × 10 ⁻⁷ mol in 0.1 mL of methylene chloride), RHODORSIL 2074 (1.99 × 10 ⁻³ g, 1.96 × 10 ⁻⁶ mol, in 0.1 mL of methylene chloride) as a photoacid generator ) And mesitylene (1.30 g) were added to prepare varnish V8.
This varnish V8 was used after being filtered with a 0.2 μm pore filter.

<< Preparation of Varnish V9 >>
HxNB (42.03 g, 0.24 mol) and SiX (7.97 g, 0.026 mol) were weighed and placed in a glass bottle.

  To this monomer solution, IRGANOX 1076 (0.5 g) and IRGAFOS 168 (0.125 g) were added as antioxidants to obtain a monomer antioxidant solution.

In a solution (9.15 g) of the above polymer P6 dissolved in mesitylene so as to be 10 wt%, a monomer antioxidant solution (1.53 g) and Pd785 (2.52 × 10 ⁻⁴ g, 3.21 × 10 ⁻⁷ mol, in 0.1 mL of methylene chloride), as a photoacid generator, RHODORSIL 2074 (1.30 × 10 ⁻³ g, 1.28 × 10 ⁻⁶ mol, in 0.1 mL of methylene chloride) ) And mesitylene (0.645 g) were added to prepare varnish V9.
This varnish V9 was used after being filtered with a 0.2 μm pore filter.

<< Preparation of Varnish V10 >>
HxNB (42.03 g, 0.24 mol) and SiX (7.97 g, 0.026 mol) were weighed and placed in a glass bottle.

  To this monomer solution, IRGANOX 1076 (0.5 g) and IRGAFOS 168 (0.125 g) were added as antioxidants to obtain a monomer antioxidant solution.

To a solution (20 g) of the above polymer P3 dissolved in mesitylene so as to be 10 wt%, a monomer antioxidant solution (2.4 g) and Pd785 (3.95 × 10 ⁻⁴ g, 5. 03 × 10 ⁻⁷ mol in 0.1 mL of methylene chloride), as a photoacid generator, RHODORSIL 2074 (2.55 × 10 ⁻³ g, 2.51 × 10 ⁻⁶ mol, in 0.1 mL of methylene chloride) and Toluene (2.5 g) was added to obtain varnish V10.
This varnish V10 was used after being filtered through a filter having a pore size of 0.2 μm.

<< Preparation of Varnish V11 >>
HxNB (42.03 g, 0.24 mol) and SiX (7.97 g, 0.026 mol) were weighed and placed in a glass bottle.

  To this monomer solution, IRGANOX 1076 (0.5 g) and IRGAFOS 168 (0.125 g) were added as antioxidants to obtain a monomer antioxidant solution.

In a solution (20 g) of the above polymer P8 dissolved in mesitylene so as to be 10 wt%, a monomer antioxidant solution (2.4 g) and Pd785 (3.95 × 10 ⁻⁴ g, 5. 03 × 10 ⁻⁷ mol in 0.1 mL of methylene chloride), as a photoacid generator, RHODORSIL 2074 (2.55 × 10 ⁻³ g, 2.51 × 10 ⁻⁶ mol, in 0.1 mL of methylene chloride) and Toluene (6.12 g) was added to prepare varnish V11.
This varnish V11 was used after being filtered with a filter having a pore size of 5 μm.

<< Preparation of Varnish V12 >>
HxNB (42.03 g, 0.24 mol) and SiX (7.97 g, 0.026 mol) were weighed and placed in a glass bottle.

  To this monomer solution, IRGANOX 1076 (0.5 g) and IRGAFOS 168 (0.125 g) were added as antioxidants to obtain a monomer antioxidant solution.

In a solution (30 g) of the above polymer P9 dissolved in mesitylene so as to be 10 wt%, a monomer antioxidant solution (1.0 g) and Pd785 (1.65 × 10 ⁻⁴ g, 2. 10 × 10 ⁻⁷ mol in 0.1 mL of methylene chloride), RHODORSIL 2074 (8.51 × 10 ⁻⁴ g, 8.38 × 10 ⁻⁷ mol, in 0.1 mL of methylene chloride) and photoacid generator Toluene (5.0 g) was added to prepare varnish V12.
This varnish V12 was used after being filtered with a 0.2 μm pore filter.

<< Preparation of Varnish V13 >>
HxNB (42.03 g, 0.24 mol) and SiX (7.97 g, 0.026 mol) were weighed and placed in a glass bottle.

  To this monomer solution, IRGANOX 1076 (0.5 g) and IRGAFOS 168 (0.125 g) were added as antioxidants to obtain a monomer antioxidant solution.

In a solution (30 g) of the polymer P14 dissolved in mesitylene so as to be 30 wt%, a monomer antioxidant solution (2.0 g) and Pd785 (3.29 × 10 ⁻⁴ g, 4. 19 × 10 ⁻⁷ mol, in 0.1 mL of methylene chloride), as a photoacid generator, TAG-372R (7.63 × 10 ⁻⁴ g, 8.38 × 10 ⁻⁶ mol, in 0.1 mL of methylene chloride) And toluene (10.0 g) was added to prepare varnish V13.
The composition of each varnish prepared above is summarized in Table 2 below.

  Moreover, as shown below, each varnish V21-V23 was prepared, respectively. Each varnish was prepared under a yellow light because it contained a photosensitive material.

<< Preparation of Varnish V21 >>
To the polymer P12 (5 g) described above, mesitylene (20 g), Irganox 1076 (0.05 g) and Irgafos 168 (0.0125 g) as antioxidants, and RHODORSIL 2074 (release agent) as a photoacid generator (release agent) 4.0 × 10 ⁻³ g in 0.1 mL of methylene chloride) was added to prepare varnish V21.
This varnish V21 was passed through a 0.2 μm pore filter for use.

<< Preparation of Varnish V22 >>
To the above polymer P13 (5 g), mesitylene (20 g), Irganox 1076 (0.05 g) and Irgafos 168 (0.0125 g) as antioxidants, and RHODORSIL 2074 (4.0 ×) as a photoacid generator. 10 ⁻³ g in 0.1 mL of methylene chloride) was added to prepare varnish V22.
This varnish V22 was passed through a 0.2 μm pore filter for use.

<< Preparation of Varnish V23 >>
Varnish V23 was prepared by adding mesitylene (20 g) and Irganox 1076 (0.05 g) and Irgafos 168 (0.0125 g) as an antioxidant to the polymer P14 (5 g).

This varnish V23 was passed through a 0.2 μm pore filter for use.
The composition of each varnish prepared above is summarized in Table 3 below.

4). Production and evaluation of optical waveguide structure 4-1. Production of Optical Waveguide Structure Ten optical waveguide structures of Examples 1 to 5 and Comparative Example were produced as shown below.

  In addition, the viscosity was adjusted and used for the varnish by removing or adding a solvent.

Example 1
First, as a cladding layer forming material, varnish V8 (viscosity: 750 cP) is poured onto a 250 μm thick polyethylene terephthalate (hereinafter abbreviated as “PET”) film and spread to a substantially constant thickness with a doctor blade. (Wet state thickness: 70 μm). This obtained the 1st layer.

  Thereafter, varnish V9 (viscosity: 1000 cP) was poured onto the first layer as a core layer forming material, and spread to a substantially constant thickness with a doctor blade (wet thickness: 80 μm). This obtained the 2nd layer.

  Finally, varnish V8 (viscosity: 1500 cP) was poured onto the second layer as a clad layer forming material and spread to a substantially constant thickness with a doctor blade (wet thickness: 80 μm).

  Thereafter, the coated PET film was placed on a hot plate and heated at 50 ° C. for 30 minutes to evaporate the solvent to obtain a solid laminated film.

This film was irradiated with UV light (wavelength: 365 nm) through a positive photomask (irradiation amount = 3000 mJ / cm ² ), and then on a hot plate at 45 ° C. for 30 minutes, followed by 85 ° C. for 30 minutes. Furthermore, it heated at 150 degreeC for 60 minutes. As a result, a linear optical waveguide having a width of 0.5 cm and a length of 10 cm was obtained.

  When the film was placed on a 45 ° C. hot plate for 10 minutes, the pattern of the linear core (width: 50 μm) could be visually confirmed on the film.

  Further, in the obtained optical waveguide, the average thickness of the core layer was 50 μm, and the average thickness of the cladding layers (upper and lower portions) was 50 μm.

  Next, a copper layer (conductor layer) having an average thickness of 45 μm was bonded to both surfaces of the optical waveguide by a roll laminating method to produce an optical waveguide structure.

(Example 2)
First, as a cladding layer forming material, varnish V11 (viscosity: 750 cP) was poured onto a PET film having a thickness of 250 μm and spread to a substantially constant thickness with a doctor blade (wet thickness: 70 μm). . This obtained the 1st layer.

  Thereafter, varnish V10 (viscosity: 1000 cP) was poured onto the first layer as a core layer forming material, and spread to a substantially constant thickness with a doctor blade (wet thickness: 80 μm). This obtained the 2nd layer.

  Finally, varnish V11 (viscosity: 1500 cP) was poured onto the second layer as a clad layer forming material and spread to a substantially constant thickness with a doctor blade (wet thickness: 80 μm).

  Thereafter, the coated PET film was placed on a hot plate and heated at 50 ° C. for 45 minutes to evaporate the solvent to obtain a solid laminated film.

This film was irradiated with UV light (wavelength: 365 nm) through a positive photomask (irradiation amount = 3000 mJ / cm ² ), then in an oven at 50 ° C. for 30 minutes, then at 85 ° C. for 30 minutes, and further 150 Heat at 60 ° C. for 60 minutes. As a result, a linear optical waveguide having a width of 0.5 cm and a length of 10 cm was obtained.

  When the film was placed in an oven at 50 ° C. for 10 minutes, the pattern of the core (width: 50 μm) could be visually confirmed on the film.

  In the obtained optical waveguide, the average thickness of the core layer was 50 μm, and the average thickness of the cladding layers (upper and lower portions) was 46 μm.

  Next, a copper layer (conductor layer) having an average thickness of 45 μm was bonded to both surfaces of the optical waveguide by a roll laminating method to produce an optical waveguide structure.

(Example 3)
First, as a cladding layer forming material, varnish V13 (viscosity: 750 cP) was poured onto a PET film having a thickness of 250 μm and spread to a substantially constant thickness with a doctor blade (thickness in a wet state: 70 μm). This obtained the 1st layer.

  Thereafter, varnish V12 (viscosity: 1000 cP) was poured onto the first layer as a core layer forming material, and spread to a substantially constant thickness with a doctor blade (wet thickness: 80 μm). This obtained the 2nd layer.

  Finally, varnish V13 (viscosity: 1500 cP) was poured onto the second layer as a clad layer forming material and spread to a substantially constant thickness with a doctor blade (wet thickness: 80 μm).

  Thereafter, the coated PET film was placed on a hot plate and heated at 50 ° C. for 45 minutes to evaporate the solvent to obtain a solid laminated film.

This film was irradiated with UV light (wavelength: 365 nm) through a positive photomask (irradiation amount = 3000 mJ / cm ² ), then in an oven at 50 ° C. for 30 minutes, then at 85 ° C. for 30 minutes, and further 150 Heat at 60 ° C. for 60 minutes. As a result, a linear optical waveguide having a width of 0.5 cm and a length of 10 cm was obtained.

  When the film was placed in an oven at 50 ° C. for 10 minutes, the pattern of the core (width: 50 μm) could be visually confirmed on the film.

  In the obtained optical waveguide, the average thickness of the core layer was 50 μm, and the average thickness of the cladding layers (upper and lower portions) was 45 μm.

  Next, a copper layer (conductor layer) having an average thickness of 45 μm was bonded to both surfaces of the optical waveguide by a roll laminating method to produce an optical waveguide structure.

Example 4
First, as a cladding layer forming material, varnish V23 (viscosity: 750 cP) was poured onto a glass plate having a thickness of 1 mm and spread to a substantially constant thickness with a doctor blade (wet state thickness: 70 μm). . This obtained the 1st layer.

  Thereafter, varnish V21 (viscosity: 1000 cP) was poured onto the first layer as a core layer forming material, and spread to a substantially constant thickness with a doctor blade (wet state thickness: 80 μm). This obtained the 2nd layer.

  Finally, as a cladding layer forming material, varnish V23 (viscosity: 1500 cP) was poured onto the second layer and spread to a substantially constant thickness with a doctor blade (wet thickness: 80 μm). .

  Thereafter, the coated glass plate was placed on a hot plate and heated at 50 ° C. for 30 minutes to evaporate the solvent, thereby obtaining a solid laminated film.

This film was irradiated with UV light (wavelength: 365 nm) through a positive photomask (irradiation amount = 3000 mJ / cm ² ), and then heated on a hot plate at 85 ° C. for 30 minutes and further at 150 ° C. for 60 minutes. . As a result, a linear optical waveguide having a width of 0.5 cm and a length of 10 cm was obtained.

  When the film was placed on a hot plate at 85 ° C. for 30 minutes, the pattern of the core (width: 50 μm) could be visually confirmed on the film.

  In the obtained optical waveguide, the average thickness of the core layer was 50 μm, and the average thickness of the cladding layers (upper and lower portions) was 46 μm.

  Next, a copper layer (conductor layer) having an average thickness of 45 μm was bonded to both surfaces of the optical waveguide by a roll laminating method to produce an optical waveguide structure.

(Example 5)
First, as a cladding layer forming material, varnish V23 (viscosity: 750 cP) was poured onto a glass plate having a thickness of 1 mm and spread to a substantially constant thickness with a doctor blade (wet state thickness: 70 μm). . This obtained the 1st layer.

  Thereafter, varnish V22 (viscosity: 1000 cP) was poured onto the first layer as a core layer forming material, and spread to a substantially constant thickness with a doctor blade (wet thickness: 80 μm). This obtained the 2nd layer.

  Finally, varnish V23 (viscosity: 1500 cP) was poured onto the second layer as a clad layer forming material and spread to a substantially constant thickness with a doctor blade (wet thickness: 80 μm).

  Thereafter, the coated glass plate was placed on a hot plate and heated at 50 ° C. for 30 minutes to evaporate the solvent, thereby obtaining a solid laminated film.

This film was irradiated with UV light (wavelength: 365 nm) through a positive photomask (irradiation amount = 3000 mJ / cm ² ), and then heated on a hot plate at 85 ° C. for 30 minutes and further at 150 ° C. for 60 minutes. . As a result, a linear optical waveguide having a width of 0.5 cm and a length of 10 cm was obtained.

  When the film was heated at 85 ° C. for 30 minutes, the pattern of the core (width: 50 μm) could be visually confirmed on the film.

  In the obtained optical waveguide, the average thickness of the core layer was 50 μm, and the average thickness of the cladding layers (upper and lower portions) was 45 μm.

  Next, a copper layer (conductor layer) having an average thickness of 45 μm was bonded to both surfaces of the optical waveguide by a roll laminating method to produce an optical waveguide structure.

(Comparative example)
First, varnish V8 (viscosity: 750 cP) was poured onto a glass plate as a cladding layer forming material and spread to a substantially constant thickness using spin coating (wet thickness: 70 μm).

Next, it is placed on a hot plate, heated at 100 ° C. for 10 minutes, irradiated with UV light without a photomask (irradiation amount = 400 mJ / cm ² ), and then 110 ° C. for 15 minutes and 160 ° C. for 1 hour. Heated. Thereby, a clad layer was obtained.

  Next, as a core layer forming material, varnish V9 (viscosity: 1000 cP) was poured onto the clad layer and spread to a substantially constant thickness with a doctor blade (wet thickness: 80 μm).

  The coated glass plate was then placed on a ventilated level table overnight to evaporate the solvent and form a substantially dry solid film.

The next day, this solid film was irradiated with UV light (wavelength: 365 nm) through a photomask (irradiation amount = 3000 mJ / cm ² ), heated at 45 ° C. for 30 minutes, then heated at 85 ° C. for 30 minutes, Furthermore, it heated at 150 degreeC for 60 minutes. As a result, a linear optical waveguide having a width of 0.5 cm and a length of 10 cm was obtained.

  In addition, the pattern of the linear core part (width: 50 micrometers) was able to be confirmed visually when it heated at 45 degreeC for 30 minutes.

  Next, as a cladding layer forming material, varnish V8 (viscosity: 1500 cP) was poured onto the core layer and spread to a substantially constant thickness with a spin coater (wet thickness: 80 μm).

This coated glass plate was placed on a hot plate and heated at 100 ° C. for 10 minutes, and irradiated with UV light without a photomask (irradiation amount: 400 mJ / cm ² ). Subsequently, it was cured at 110 ° C. for 15 minutes and then at 160 ° C. for 1 hour. As a result, a linear optical waveguide having a width of 0.5 cm and a length of 10 cm was obtained.

  In the obtained optical waveguide, the average thickness of the core layer was 50 μm, and the average thickness of the cladding layers (upper and lower portions) was 46 μm.

  Next, a copper layer (conductor layer) having an average thickness of 45 μm was bonded to both surfaces of the optical waveguide by a roll laminating method to produce an optical waveguide structure.

3-2. Evaluation 3-2-1. Measurement of Light Propagation Loss For each of the optical waveguide structures of Examples and Comparative Examples, the light propagation loss was measured using the “cutback method”.

This is because the light generated from the laser diode is input from one end of the core part through the optical fiber, the output from the other end is measured, and the length of the core part is cut into several lengths. This was done by measuring the light output.
The total optical loss in each length of the core part is expressed by the following formula.

Total optical loss (dB) = -10 log (Pn / Po)
Where Pn is the measured output at the other end of each core portion of length P1, P2,... Pn, and Po is at the end of the optical fiber before coupling the optical fiber to one end of the core portion. This is the measurement output of the light source.

  Next, the total optical loss is plotted as in FIG. 8 (Chart 1). The regression line of this data is expressed by the following equation.

y = mx + b
In the formula, m represents a light propagation loss, and b represents a coupling loss.

3-2-2. Adhesion Test An adhesion test between the core layer and the clad layer was performed on the optical waveguide structures of the examples and the comparative examples.

This was performed by a peel test in which the clad layer was peeled upward 90 ° from the core layer.
The results of measurement of light propagation loss and adhesion test are shown in Table 4 below.

In addition, each numerical value in a table | surface shows an average value of 5 each.
As is clear from Table 4, each of the optical waveguide structures of each example has a small light propagation loss, high optical transmission performance, and high adhesion between the core layer and the cladding layer. It was a thing.

  On the other hand, the optical waveguide structure of the comparative example had a light propagation loss slightly inferior to that of the example, but the adhesion between the core layer and the clad layer was clearly inferior.

  Further, after the optical waveguide structures of the examples and the comparative examples were exposed to a high humidity environment (60 ° C., 90% RH, 2000 hours), the light propagation loss was measured in the same manner as described above. As a result, each of the optical waveguide structures of the respective examples showed a tendency that a decrease in light propagation loss was suppressed to be lower than that of the optical waveguide structure of the comparative example.

  Further, as a constituent material of the cladding layer, a copolymer of alkyl norbornene and methyl glycidyl ether norbornene, a copolymer of alkyl norbornene and 2- (5-norbornenyl) methyl acrylate, a copolymer of alkyl norbornene and alkoxysilyl norbornene, alkyl norbornene and Terpolymer of 2- (5-norbornenyl) methyl acrylate and norbornenylethylalkoxysilane, terpolymer of alkyl norbornene, 2- (5-norbornenyl) methyl acrylate and methyl glycidyl ether norbornene, alkyl norbornene and methyl glycidyl Using the terpolymer of ether norbornene and norbornenylethylalkoxysilane, an optical waveguide structure was produced in the same manner as described above. And was measured for light propagation loss, tended to light propagation loss is reduced. This is considered to be caused by the fact that these polymers have a polymerizable group to improve the adhesion between the respective layers.

  Furthermore, the conductor layers of the optical waveguide structures (before exposure to a high humidity environment) produced in each of the examples and comparative examples are patterned to form wirings, and light emitting elements and light receiving elements are formed at predetermined locations. Was mounted to produce a composite device.

  When these composite devices were operated, it was confirmed that any of the composite devices using the optical waveguide structures of the examples and comparative examples can operate at high speed.

DESCRIPTION OF SYMBOLS 9 Optical waveguide structure 90 Optical waveguide 91,92 Clad layer 93 Core layer 94 Core part 95 Clad part 901,902 Conductor layer 915 Polymer 920 Additive 925 Irradiation area 930 Active radiation 935 Mask 9351 Opening 940 Unirradiated area 1000 Support substrate 1110 1st layer 1120 2nd layer 1130 3rd layer 2000 Laminate

Claims (9)

A method for producing an optical waveguide, comprising: a core layer comprising a core portion; a clad portion having a lower refractive index than the core portion; and a clad layer provided in contact with at least one surface of the core layer,
Supplying a cladding layer forming material to form a liquid film, and obtaining a first layer in a state where the liquid film does not completely solidify or cure;
On the first layer, a core layer forming material whose refractive index is changed by irradiation with actinic radiation or by further heating is supplied to form a liquid film, and the liquid film is completely solidified or cured. A second step of obtaining a second layer in an unachieved state and forming a laminate;
By selectively irradiating the laminate with the active radiation or further heating, a refractive index difference is generated between the active radiation irradiated region and the non-irradiated region in the second layer. Thus, a third step in which one of the irradiated region and the non-irradiated region is the core portion, and the other is the cladding portion,
By subjecting the laminate to a heat treatment at a second temperature higher than the temperature of the heat treatment, the first layer and the second layer are collectively solidified or cured at a time. 4 processes,
The core layer forming material includes a polymer and a monomer that is compatible with the polymer and has a refractive index different from that of the polymer.   The unreacted monomer gathers from the other region as the monomer reaction proceeds in one of the irradiated region and the unirradiated region of the second layer in the third step. The manufacturing method of the optical waveguide as described in any one of.   The method for manufacturing an optical waveguide according to claim 1, wherein the monomer includes a crosslinkable monomer.   The method for producing an optical waveguide according to claim 1, wherein the monomer is mainly a norbornene-based monomer. The core layer forming material includes a substance activated by irradiation with the actinic radiation, a main chain and a branch from the main chain, and at least a part of a molecular structure from the main chain by the action of the activated substance. A polymer having a leaving group capable of leaving,
In the third step, by irradiating the laminated body with the actinic radiation, the substance is activated in the irradiation region of the second layer, and the leaving group of the polymer is released. Then, by causing a refractive index difference between the irradiated region and the non-irradiated region, one of the irradiated region and the non-irradiated region is used as the core portion, and the other is used as the cladding portion. Item 5. A method for manufacturing an optical waveguide according to any one of Items 1 to 4.   6. The method for producing an optical waveguide according to claim 1, wherein the polymer is mainly a norbornene-based polymer. The cladding layer forming material contains a polymer,
The method for producing an optical waveguide according to claim 1, wherein the polymer is mainly a norbornene-based polymer.   The method for manufacturing an optical waveguide according to claim 1, further comprising a step of drying the laminated body prior to the third step.   An optical waveguide manufactured by the method for manufacturing an optical waveguide according to claim 1.

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