JPS61138253A - Ultraviolet-hardenable resin composition - Google Patents

Abstract

PURPOSE:To enhance hardening speed in the presence of oxygen by mixing an acrylate type polymer as a filler, a free-radically polymerizable monomer having an unsatd. double bond, a UV polymn. initiator, and a sensitizer each in a specified proportion. CONSTITUTION:The UV resin compsn. is prepared by mixing as essential components, (A) the acrylate type polymer as a filler, (B) the free-radically polymerizable monomer or oligomer having an unsatd. double bond, (C) the UV polymerization initiator of a mixture of (a) benzophenone, (b) 4,4- diethylaminobenzophenone, (c) tribromomethylphenylsulfone, and (d) 2- mercaptobenzothiazole, in an amt. of 5-15pts.wt. of (C) per 100pts.wt. of (B), and the total wt. of (a) and (b) being less than the total weight of (c) and (d), and a sensitizer.

Description

Detailed Description of the Invention [Technical Field 1] The present invention relates to ultraviolet curing, which is applied as a photosensitive layer to 7r) resist dry film used in forming wiring patterns on printed wiring boards and in turret masks. The present invention relates to a synthetic resin composition.

[Background Art J] When forming a mask, solder mask, etc. for forming a wiring pattern on a printed wiring board, a resist ink is applied to the printed wiring board substrate by silk screen printing, etc., using the 7-Otrenost method. 7t) In the Renost method, the method of printing and applying liquid photoresist, a liquid photosensitive liquid, to the surface of the printed wiring board substrate has become mainstream, but this method has problems with workability, safety, etc. Because there is
Recently, the construction method using Otrenost dry film has been attracting attention due to its excellent workability and safety, and its range of use is gradually expanding.

7 The conventionally used otorenost dry film is polyethylene terephthalate film (
A photosensitive liquid made of an ultraviolet curable resin composition is coated on one side of a support film such as PET film) and dried 51! A photosensitive layer is applied to the surface of the photosensitive layer, and a cover film made of a polyolefin film such as a polypropylene film is laminated on the surface of the photosensitive layer.Then, this 7-Otrenost dry film is used to form a wiring pattern on a printed wiring board substrate. To form the film, use a dry film laminator to first peel off the cover film to expose the photosensitive layer, and then apply 7r) Renost Dry to the surface of the printed wiring board substrate, with the support film on the outside and the photosensitive layer on the inside. The films are stacked and the photosensitive layer is adhered to the printed wiring board substrate while being pressed with a heating roll or the like.6 Next, a pattern mask film having a wiring pattern shape is stacked on top of the support film and vacuum suction is applied. The patterned mask film is brought into close contact or in a so-called soft contact state, and exposed to ultraviolet light having a wavelength of, for example, 365n haze, to photocure the photosensitive layer in the portions where the ultraviolet light passes through the pattern mask film. Thereafter, the support film is peeled off and a developer is sprayed onto the photosensitive layer to dissolve and remove the uncured portion of the photosensitive layer. The photosensitive layer is then hardened using an etching machine to form a wiring pattern by etching away the copper foil and metal foil of the printed wiring board except for the remaining portions, or the photosensitive layer is removed using an electroless plating machine. A wiring pattern is formed by growing a film of metal such as copper on the surface of the printed wiring board substrate other than the portions that remain after hardening. After forming the wiring pattern in this way, if the hardened portion of the photosensitive layer is not needed, peel it off 111.
1!11 to dissolve or swell this part and peel it off.

In such conventional 7-otrenost dry film, the photopolymerization of the ultraviolet curable resin composition is generally inhibited by the presence of oxygen, so that the photopolymerization of the ultraviolet curable resin composition is generally inhibited by the presence of oxygen. Therefore, the photosensitive layer is photopolymerized in a state where oxygen (air) is blocked by a support film. But what's more?
If the photosensitive layer is exposed with a support film covering it, the resolution will decrease due to the refraction and spreading of light by the support film, making it difficult to create fine patterns. It also becomes difficult to automate lamination of otorenost dry film and soft contact exposure. Furthermore, since the support film must be peeled off during development, automation of wiring pattern formation becomes difficult.

Therefore, various attempts have been made to photopolymerize the photosensitive layer in an exposed state without being covered with a support film. 46-35
687 Publication, Special Publication No. 46-9179, Special Publication No. 5
As provided in JP-A-5-49729, JP-A-51-71123, JP-A-56-75643, etc., an oxygen inhibition prevention layer is formed on the surface of the photosensitive layer to block the influence of oxygen. There have been attempts to do this, but this method requires an additional step to form an oxygen inhibition prevention layer, so it cannot be said to be a fundamental solution.
That is, the above problems can be fundamentally solved only by providing an ultraviolet curable resin composition that can be cured by ultraviolet light even in the presence of oxygen.

However, as such ultraviolet curable resin compositions that can be cured in the presence of oxygen, Japanese Patent Publication No. 46-33530, Japanese Patent Publication No. 53-40123, and Japanese Patent Application Laid-open No. 56-1
Although there are some methods provided by Publication No. 1904, etc., they each have their own merits and demerits, and they have not yet been put to practical use.

[Object of the Invention 1] The present invention has been made in view of the above points, and an object of the present invention is to provide an ultraviolet curable resin composition that can be rapidly cured in the presence of oxygen.

[Disclosure of the Invention J] However, the present invention comprises (A) an acrylic compound as a filled polymer, (B)
A radically polymerizable monomer having an unsaturated double bond and/or
or oligomer, (C) having (A), (B), and (C') of a system of ultraviolet polymerization initiator and sensitizer as main components, and (C) having (C) as a main component;
a) Benzophenone (b) 4,4'-diethylamide/benzophenone (c)
It is a mixture of tribromomethylphenylsulfone (d) 2-mercaptobenzothiazo-1 and (i) (b) (
c) The total amount of (d) is 5 to 15% by weight of (B), the sum of weights of (a) and (cl) is smaller than the sum of weights of (c) and (d), and (a) The weight ratio of (el) is 10:1 to 1
2:1 and the weight ratio of (c) to (d) is 2:1 ~
The first invention is an ultraviolet curable resin composition characterized by a ratio of 10 to 1, (A) a half-esterified copolymer of vinyltoluene, itaconic acid, and maleic acid as a filled polymer; (B) A lanocal polymerizable monomer and/or oligomer having an unsaturated double bond, (C) a system of ultraviolet polymerization initiator and sensitizer (A), (B), and (C) as main components; stomach)
It is a mixture of benzophenone (b) 4'-diethylaminobenzo7ene/ene (c) tribromomethylphenylsulfone (d) 2-norcaptobenzothiazole, and (a) (b) (
)), the total amount of (d) is 5 to 15% by weight of (B), and (
The sum of weights of (a) and (b) is the same as or greater than the sum of weights of (11) and (d), and the weight ratio of (a) to (b) is 10:1
The second invention is an ultraviolet curable resin composition characterized in that the weight ratio of <I> to (d) is 2:1 to 10:1, and the following: The present invention will be described in detail.

7. When using the ultraviolet curable resin composition according to the present invention to form a photosensitive layer for photoresist film, either one-positive type or full-positive type can be used; In addition, it can be used with any of the solvent development stripping type, alkaline aqueous solution development stripping type, and dry development type. In order to meet this requirement, it is preferable to apply an ultraviolet curable resin composition to both sides of the support film to form a photosensitive layer on both sides, in accordance with the method of using the photoresist dry film described below. In order to have different adhesion (peelability) of the photosensitive layer on each side, different UV curable resin compositions with corresponding adhesive properties were prepared, and each UV curable resin composition was It is preferable to coat each side of the support film.

However, by applying physical or chemical treatment to each side of the support film to make the adhesion of each side of the support film different, even if the formulation of the ultraviolet curable resin composition is the same, The adhesion of the photosensitive layers on each side can be made to differ, and this may be preferable in some cases.

As is well known, the ultraviolet curable resin composition contains (A) a filled polymer, CB) a photopolymerizable monomer and/or oligomer, (C) a photopolymerization initiator, a polymerization agent system, CD) a thermal polymerization inhibitor, ( E) The dye system, (F) other additives, etc., and (G) the solvent are combined to give 111g&.

First, as the filled polymer (A), an acrylic compound is used in the first invention, and a half-esterified copolymer of vinyltoluene, itaconic acid, and maleic acid is used in the second invention. is used. A typical example of acrylic compound polymers is polymethyl methacrylate-F, but in order to make it possible to develop with alkali dissolution to lI wetness, a copolymer of methyl methacrylate and methacrylic acid, etc., has been developed. It is preferable to use the copolymers described in No. 1, US Pat. Those described in JP-A-57-2035 and the like can be used. In order to make them soluble in alkaline water and swellable, -〇〇〇H groups, -3O2H groups, -NHs groups, etc. may be subjected to addition reaction or graft polymerization (Japanese Patent Publication No. 50-15033). (Introduced in publications such as Japanese Patent Publication No. 57-40841, etc.) However, a small amount of alkali-insoluble polymers can also be mixed and used.

As the photopolymerizable radically polymerizable monomer and/or oligomer (B), monofunctional and/or polyfunctional acrylic ester-based monomers having unsaturated double bonds are used. In order to make it soluble in alkaline water to swellable type, -COO
Some or all of the compounds containing H groups, -3O, H groups, -NH groups, etc. will be used, but if they are made too hydrophilic, they will not be used in developing solutions, etching solutions, or electroless plating solutions. There is a risk that the cured film will be attacked by the action of
) It is necessary to reconsider the selection as appropriate in consideration of the filling polymer.1 For example, trimethylolpropane tri(meth)acrylate, etc. Japanese Patent Publication No. 1983-40537, 4
# Publication No. 56-8417, Special Publication No. 59-31052
Polymerizable monomers described in Japanese Patent Publication No. 1, etc. can be used. Monofunctional monomers such as trimethyl 7-minoethyl methacrylate, acrylic acid, methyl methacrylate, 2-ethylhexyl (ivy) 7-acrylate, etc. can also be used, but these are mainly used as plasticizers, adhesives,
It acts as a pH adjuster, and therefore, these substances can be used in the composition of the photosensitive layer on each side in order to vary the adhesion (releasability) of the photosensitive layer on each side to the support film. become.

(The system of ultraviolet polymerization initiator and stimulant for C1 includes (a) benzophenone (BP), (b) 4,4'-noethylaminopenzophenone (EAB), (c) a, a, α
-tribromomethylphenylsulfone (BMPS), (
1) Four types of 2-mercaptobenzothiazole (MBT) are used as a quaternary system. In addition to these, a wide variety of substances can be used, and can be used as a combination of multiple elements.For example, carbonyl compounds, nitrogen-containing heterocyclic compounds, organic sulfur compounds, peroxide compounds, redox compounds, azo In addition, noazo compounds, halogen compounds, photoreducible dyes, etc. can be used (Special Publication No. 42
-16587 Publication, Special Publication No. 54-25957,
Japanese Patent Publication No. 47-1895, Japanese Patent Publication No. 57-14164
(Introduced in Japanese Patent Publication No. 19284-19284, Japanese Patent Publication No. 44-1972)
6361 Publication, Japanese Patent Publication No. 44-20067, Japanese Patent Publication No. 48-38403, Publication No. 37902-1982, Publication No. 43988-1988, Japanese Patent Publication No. 53-4
3989 Publication, Special Publication No. 59-818, Special Publication No. 1987
9-1283, JP 54-130693, JP 53-37211, JP 55-609
This can be carried out according to the methods described in Japanese Patent Application Laid-open No. 42, Japanese Patent Application Laid-open No. 171406/1983, and the like. Among these are Special Publication No. 40-17986 and Special Publication No. 40-17986.
As described in Japanese Patent Application No. 5-37377, there are many compounds, such as halogen compounds, which have the effect of imparting salt resistance and also function as coloring agents for photochromic compounds.

(As thermal polymerization inhibitors for DJ, the inhibitors mixed in commercially available Motsumar for polymerization are not sufficient, and it is often necessary to add them. p-benzoquinone, anthraquinone, and other thermal polymerization inhibitors described in Japanese Patent Publication No. 55-38961 can be used.In the present invention, 7t) When the resist dry film is used in the structure described below, the cover The photosensitive layer on which the film is laminated is exposed to heat a-
Since heating is applied twice using the UV curable resin composition, it is necessary to pay more attention to the weighing accuracy when adding the thermal polymerization inhibitor to the ultraviolet curable resin composition than in the case of a photosensitive layer on which a cover film is not laminated.

As the dye system (E), color-forming compounds such as leuco dyes are usefully used. A mixed system of a dye and a color-forming compound can also be used. In this case, JP-A-51-7
As shown in Japanese Patent Laid-open No. 3432 and Japanese Patent Application Laid-Open No. 56-75642, exposure gives a colored visible bright m-image of a mixed tone of a dye and a colored substance. Of course, it is not necessary to contain dye, but in this case,
As suggested in Japanese Patent No. 9-28325, it is desirable to use a colored and transparent support film, and the coloring agent for coloring the coloring compound is the above-mentioned (C).
It is considered to be included in the

Other additives in (F) include plasticizers, toners, dispersants, anti-capri agents, antistatic agents, adhesion improvers, etc.
These may be added separately, or may be used as chemically bonded to the compounding agents (A) to (E) above.

As the solvent (G), an organic solvent is mainly used,
Methyl ethyl ketone, toluene, isopropyl alcohol, etc. are used as examples.

Thus, an ultraviolet curable resin composition is prepared by mixing each of the above-mentioned formulations, but in the invention, (a) benzo-7enone (
BP), (b) 4.4'-noethyl 7minobenzo 7/
(EAB), (c) α, α, a-tribromomethylphenylsulfone (BMPSL) (d) 2-Flucaptobenzothi7zole (M B T >), their blending amounts and blending ratios It is necessary to specify, that is, the blending ratio of (a):(b) is set to a weight ratio of 10:1 to 12:1, but in this case, the ratio of (+7) is very delicate, Even if the ratio of (B) is higher than this range, the photosensitization effect will hardly improve, and the photosensitive layer will become yellowish, which may impair the appearance of the 7-otrenost dry film. If the ratio (b) is lowered, the photosensitizing effect will drop sharply.If the ratio is out of this range, only a bad effect will appear, so it is necessary to pay particular attention to the weighing accuracy of (b). In addition, the blending ratio of (c):(d) needs to be a weight ratio of 2:1 to 10:1, and especially if the amount of (d) is increased beyond this range, scum is likely to occur during development and peeling. In addition, if (2) is reduced more than this, the photosensitizing effect will be significantly reduced.
Although the theoretical elucidation of the weight sum ratio of a) + (b): (c) + (d) is insufficient, when using an acrylic compound as the filled polymer, (7%) + (
The system (d) has a more sensitive effect on photosensitization, and when a half-esterified product of a copolymer of vinyltoluene, itaconic acid, and maleic acid is used as the filled polymer, (a) + (f)
Since the system f) has a more sensitive effect on photosensitization, when using an acrylic compound as the filled polymer, set the blending weight ratio to (a) + (b) < (c) + (d), and When using a half-esterified copolymer of vinyltoluene, itaconic acid, and maleic acid as a filled polymer, (
It is necessary to set the blending weight ratio to b) + (b) ≧ (c) + (d). This is thought to be due to the compatibility between the length and thickness of the filled polymer and the system of polymerizable monomer (B), ultraviolet polymerization initiator, and sensitizer entangled therein.
In any case, it is necessary to also include a system with a lower photosensitizing effect. The reason for this is that there is a slight difference between the "1 molar extinction coefficient" disclosed in JP-A-58-171406 when measured alone and the "combined molar extinction coefficient J" measured within this composition. It is thought that this is due to the presence of
c) The total weight of (d) is set at 5 to 15% by weight based on the radically polymerizable monomer and/or oligomer of (B). If the amount of fi exceeds 15% by weight, the so-called ν-capri phenomenon tends to occur, making it necessary to use a large amount of polymerization inhibitors and anti-capri agents, which is economically disadvantageous, and if it is less than 5% by weight, the exposure will take longer. However, it takes time, and the photosensitive layer is heated by the thermal energy from the ultraviolet lamp during exposure, raising the temperature, which may cause the photosensitive layer to become sticky, resulting in problems such as sticking between the photosensitive layer and the pattern mask. A photosensitive layer is formed by coating the above ultraviolet curable resin composition on a support film and drying it, and a cover film is applied to the photosensitive layer to form a 7-otrenost dry film. It is used for storage and transportation by cutting it into a predetermined width and rolling it up.

Here, as the support film, use a transparent PET film as in the conventional 7t) Rhenost dry film, and as the cover film, use a polyolefin film such as polypropylene film, as in the conventional 7t) Rhenost dry film. I can do it. It goes without saying that it can be formed into a three-layer structure consisting of a support film, a photosensitive layer, and a cover film, similar to the conventional 7t) Renost Dry Film, but it can also be formed into a three-layer structure consisting of a support film, a photosensitive layer, and a cover film, but it can also be formed with a special structure as shown below. You can also create a 7t Trenost dry film.

That is, a photosensitive layer is formed on each side of the support film by applying an ultraviolet curable resin composition to both sides of the support film and drying, and m layers of the cover film are formed on the photosensitive layer on one side. In order to prepare a 70-ton dry film, the formation of the photosensitive layer on both sides can be continuously produced on an automated line by using a double-sided simultaneous extrusion coating device, a 70-ton drying device, or the like. At this time, the releasability of the photosensitive layer on each side of the support film with respect to the support film and the cover film is made to be different. In other words, the releasability of the photosensitive layer on which the cover film is not laminated to the support film is better than the releasability of the photosensitive layer on which the cover film is laminated to the support film or the cover film, or The releasability of the photosensitive layer with the cover film laminated to the film is better than the releasability of the photosensitive layer with no cover film laminated to the support film. The method of creating differences in the releasability of the photosensitive layer on each side of the support film has already been described.

Next, a method of using the 7r) Renost dry film produced in this way will be explained. First, the releasability of the photosensitive layer with no cover film laminated to the support film was better than that of the photosensitive layer with the cover film laminated to the support film or the cover film. In the case of 7 Otrenost dry film, the 7 Otrenost dry film is stacked on a printed wiring board substrate with the photosensitive layer on which the cover film is not laminated on the inside, and the photosensitive layer is pressed by passing it through a heated roll or the like. The layer is brought into close contact with a printed wiring board substrate, and then the photosensitive layer on which the cover film is laminated is peeled off from this adhesive layer. At this time, the three layers of the cover film, the photosensitive layer on which the cover film is laminated, and the support film are peeled off as one, and the photosensitive layer bonded to the printed wiring board substrate is exposed. .

Since the photosensitive layer on which the cover film is not laminated with respect to the special holiday film has good releasability, 3NJ is thus peeled off as one piece. In addition, this peeled three-layer film is rolled up, and then a pattern mask having a wiring pattern shape is placed over the photosensitive layer bonded to the printed wiring board substrate and brought into close contact by vacuum suction. state,
For example, the photosensitive layer is exposed to ultraviolet light having a wavelength of about 365 nm, and the photosensitive layer is photocured in the portions where the ultraviolet light passes through the pattern mask. Thereafter, the uncured portion of the photosensitive layer is dissolved and removed by spraying a developer onto the photosensitive layer.

Then, the photosensitive layer is hardened by the etching machine and the # of the printed wiring board substrate is removed except for the remaining portions.
A wiring pattern is formed by etching away metal foil such as foil, or a film of metal such as copper is grown on the surface of a printed wiring board except for the areas where the photosensitive layer is hardened using electroless plating equipment. After forming the wiring pattern in this way, if the hardened remaining portion of the photosensitive layer is unnecessary, this portion is dissolved or swelled and peeled off using a peeling device to form a printed wiring board. It is something that will be completed. On the other hand, there is a 3-layer film that has been peeled off from the 7-odrenost dry film as described above.The cover film is peeled off from the 3-layer film to expose the photosensitive layer in this 3-layer film, and the exposed photosensitive layer is turned inside. This photosensitive layer is pasted on the back side of another printed wiring board substrate different from the above or the same printed wiring board substrate as above, and is pressed with a hot roll or the like, so that the photosensitive layer is brought into close contact with the printed wiring board substrate. Glue the attachment. Although the surface of this photosensitive layer is covered with a support film, the support film may be peeled off at this stage. Then, in the same manner as above, when the surface of the support film or the support film is peeled off, a pattern mask is placed on the surface of the photosensitive layer and the photosensitive layer is photocured by UV irradiation, and if there is a support film, the support film is removed. After peeling off the photosensitive layer, the uncured portion of the photosensitive layer is dissolved and removed, and a wiring pattern is formed by etching the metal foil or electroless plating to create a printed wiring board.

In general, the releasability of the photosensitive layer on which the Kawai film is laminated to the support film is better than the releasability of one photosensitive layer on which the cover film is laminated to the support film (S). 7r) In the case of RENOST dry film, the photosensitive layer is layered on the printed wiring board substrate with the photosensitive layer on which the cover film is not laminated on the inside, and the photosensitive layer is pressed by passing it through a heated roll or the like. The layer is brought into close contact with the substrate for a printed wiring board to form an adhesive, and then the photosensitive layer on which the cover film is laminated is peeled off from the photoresist dry film that has become almost taut. At this time, the two layers of the cover film and the photosensitive layer laminated with the cover film are peeled off from the support film as one piece, so that the photosensitive layer adhered to the printed wiring board substrate is covered with the support film. do. Since the photosensitive layer on which the cover film is laminated with respect to the support film has good releasability, the two layers are thus peeled off as one from the support film. The peeled two-layer film is rolled up and then a pattern mask having a wiring pattern shape is placed over the support film covering the photosensitive layer adhered to the printed wiring board substrate and brought into close contact by vacuum suction. or put it in a so-called 77-point contact state.

Of course, the pattern mask may be directly overlaid on the photosensitive layer after peeling off the support film.
The photosensitive layer is exposed to ultraviolet light having a wavelength of 65 nm, and the photosensitive layer is photocured in the areas where the ultraviolet light passes through the pattern mask. After this, if a support film is present, the support film is peeled off and a developer is sprayed onto the photosensitive layer to dissolve and remove the uncured portion of the photosensitive layer. Then, an etching machine is used to remove the copper foil and metal foil of the printed wiring board except for the parts where the photosensitive layer is hardened and remains to form a wiring pattern.
Alternatively, a wiring pattern is formed by growing a film of metal such as copper on the surface of the printed wiring board substrate other than the portion where the photosensitive layer remains after hardening using an electroless plating device. After forming the wiring pattern in this way,
If the cured remaining portion of the photosensitive layer is not needed, this portion is dissolved or swelled and peeled off using a peeling device to complete the printed wiring board. On the other hand, in the case of the two-layer film peeled off from the 7-odrenost dry film as described above, the cover film is peeled off from the photosensitive layer and the photosensitive layer is transferred to another printed wiring board substrate different from the above or the same printed wiring board as above. Lay it on the back side of the board and glue it. Then, in the same manner as above, a pattern mask is placed on this photosensitive layer, and the photosensitive layer is photocured by UV irradiation.
Furthermore, the uncured portion of the photosensitive layer is dissolved and removed, and then a wiring pattern is formed by etching the metal foil or electroless plating to complete the printed wiring board.

In this way, the printed wiring I! Wiring patterns can be formed on two sides of the tear board, and only two films, the support film and the cover film, need to be discarded to create the wiring patterns on the two sides. In other words, in the conventional 7t Trenost Dry Film I Rem 1, which has a three-layer structure of a support film, a photosensitive layer, and a cover film, each time a wiring pattern is formed on one surface of a printed wiring board substrate, the support film is The two films, the cover film and the cover film, have to be discarded, and the cost includes not only the cost of the photosensitive layer but also the cost of the support film and the cover film. , each time a wiring pattern is formed on one side of a printed wiring board substrate, a support film and a cover film are used.
Having to dispose of each film is a huge waste of material, and furthermore, disposal costs such as incineration and landfilling are required. Therefore, as mentioned above, when creating a wiring pattern on two sides, it is possible to dispose of two films, the support film and the cover film, which reduces the amount of waste film by half, making it economical (25 It is possible to reduce FusF by about 10%), meet the requirements for resource conservation, and reduce disposal costs.

Of course, in addition to forming and using a 7+r) photoresist dry film with the above-mentioned structure, it is also possible to form a 7+r) renost dry film with a 3N structure of a support film, a photosensitive layer, and a cover film as in the past, or A two-layer structure in which a photosensitive layer is formed on a support film can also be used. In this case, after attaching the photosensitive layer to the printed wiring board substrate, the support film is peeled off to expose the photosensitive layer, and in this state, the pattern mask is placed directly on the photosensitive layer and exposed. This often improves the resolution during exposure, making it possible to create wiring patterns with fine patterns, and also making it possible to automate various processes.

Next, the present invention will be specifically explained with reference to Examples.

and 19Y An ultraviolet curable resin composition was prepared by mixing the following formulations.

(Parts by weight) Half-esterified monostyrene/vinyltoluene/maleic acid/itaconic acid copolymer (molecular weight approximately 50,000 - OND Polymer VT/I manufactured by Okamoto Chemical Co., Ltd.) 3.O.trinothialpropane 177 acrylate 2.0・Benzo7ene/one (BP) 0.14・Tribromomethylphenylsulfone (BMPS) 0.06・4
．． 4'-diethylamide/benzophenone (EAB)
0.012・2-norcaptobenzothiazole (MBT) 0.02・paranodoxy7ethyl 0.04φ paratoluenesulfonamide 0.5・brilliant green o, o o s・leuco crystal violet 0.03・methyl ethyl ketone Toluene 2 and thickness 2
Using a 5μ thick untreated PET film as a support film, this ultraviolet curable resin composition was coated on one side using a variable pitch bar coater set to 75μm, and dried for 2 minutes at 80°C in a hot air dryer. A photosensitive layer was formed to prepare a 7-otrenost dry film. The thickness of the photosensitive layer was 25 μm.

Next, the iron-based plus epoxy laminate with a 35 μm thick copper foil pasted was inserted into a Debon A-type laminator, and a 7-oto-resist dry film was layered on top of it so that the photosensitive layer was in close contact with the laminate, and then heated and rolled. The support film was peeled off after lamination was carried out through a lamination mall.

Next, the electrical wiring to the vacuum pump motor of the i1DMBL exposure machine manufactured by Colite Co., Ltd. (USA) was removed, the exposure machine was put into service, and a lath dry plate with the size of a negative pattern was placed on top of the photosensitive layer as a pattern mask. exposed.

The illuminance of the exposed surface measured with an ultraviolet light meter (tJV-302) made by Oak Seisakusho is 3.5 mW/am2, and the integrated amount of fog light is 70+mJ/c2. 6 Next, 1% carbonated water soluble 8! (liquid temperature: 32° C.) was sprayed for 60 seconds to dissolve and remove the uncured portion of the photosensitive layer.

After this, cupric chloride etching (fi temperature 50'C)
was sprayed for 4 minutes to dissolve and remove the copper foil surface where the photosensitive layer was removed to create a wiring pattern, and then 5% hydroxide)
The cured portion of the photosensitive layer was removed by spraying t01L (temperature: 40°C) dissolved in water to obtain a printed wiring board.

Although the photosensitive layer was not covered by the support film and was in contact with oxygen (air), the curing progressed rapidly and favorably upon exposure, and a fine wiring pattern could be formed.

UV curable by mixing the following formulations! I
A Fat M product was prepared.

(parts by weight) ・Methyl methacrylate/butyl acrylate)/2-ethyl hequinyl methacrylate/typical compound of acrylic acid (molecular weight approximately 50,000) 3.0 ・Trimethylolpropane triacrylate
2,0 benzophenone (
BP) 0.08・Tribromomethylphenylsulfone (BMPS) 0.12・
4,4'-noethyl 7minobenzophenone (EAB)
0.007・2Mercaptobenzothiazole (MBT) 0.02・p-
t-Butylcatechol 0.04, butyl 7-thaletate 0.5, malachite green 0.005, leuco crystal bioleft 0.03, polyethylene glycol oleyl ether 0.2, methyl ethyl ketone No. 10 isopropyl alcohol 2 The above ultraviolet curable resin composition A 7-photoresist dry film was prepared in the same manner as in Example 1 using the following. Then, using this Photoreno-Kuto dry film, the copper foil-covered iron base was implanted in the same manner as in Example 1.
A printed wiring board was obtained by exposing, developing and etching the suede laminate. Even in this case, the photosensitive layer is covered with a support film and is in contact with oxygen (air), but curing progresses quickly and well by exposure, and fine wiring patterns can be formed. It was something.

[Effect of the invention 1 As mentioned above, the ultraviolet curable resin composition according to the present invention has
The action of the ultraviolet polymerization initiator combined with the quaternary system and the sensitizing system enables rapid ultraviolet curing even in the presence of oxygen. When formed using this ultraviolet curable resin composition, it is necessary to perform exposure while covered with a support film to block oxygen. This makes it possible to form wiring patterns with fine patterns and to automate the process.

Claims (1)

[Claims] [1] (A) an acrylic compound as a filled polymer, (B) a radically polymerizable monomer and/or oligomer having an unsaturated double bond, (C) an ultraviolet polymerization initiator and a sensitizer The main components are (A), (B), and (C) of the system, and (C) is (a) benzophenone (b) 4,4'-diethylaminobenzophenone (c)
It is a mixture of tribromomethylphenylsulfone (d) 2-mercaptobenzothiazole, in which the total amount of (a), (b), (c), and (d) is 5 to 15% by weight of (B), and (a) and ( The sum of the weights of (b) is smaller than the sum of the weights of (c) and (d), and (a) vs.
The weight ratio of (b) is 10:1 to 12:1, and (c)
An ultraviolet curable resin composition characterized in that the weight ratio of (d) is from 2:1 to 10:1. [2] (A) Half-esterified copolymer of vinyltoluene, itaconic acid, and maleic acid as a filled polymer, (B) Radically polymerizable monomer and/or oligomer having an unsaturated double bond, (C) Ultraviolet light The main components are (A), (B), and (C) of a polymerization initiator and sensitizer system, and (C) is (a) benzophenone (b) 4,4'-diethylaminobenzophenone (c)
It is a mixture of tribromomethylphenylsulfone (d) 2-mercaptobenzothiazole, in which the total amount of (a), (b), (c), and (d) is 5 to 15% by weight of (B), and (a) and ( The sum of the weights of (b) is the same as or greater than the sum of the weights of (c) and (d), and (a)
The weight ratio of (b) is 10:1 to 12:1, and (
An ultraviolet curable resin composition characterized in that the weight ratio of (c) to (d) is from 2:1 to 10:1.