JPH05266708A - Printing ink for silver conductor circuit and method of forming silver conductor circuit - Google Patents

Abstract

PURPOSE:To provide a preset pattern in a convenient and smooth way by using an offset printing and to form a printed pattern with high resolution and positional precision. CONSTITUTION:A printing ink for a silver conductor circuit is obtained by containing at least one type of resin component selected out of terpine polymer, terpine phenol copolymer,. alpha-pinene polymer and beta-pinene polymer resin, above- mentioned polymer modified resin and hydrogen added resin, solvent component, metallic silver powder and flux component, if necessary. The ink is used to print a pattern on a substrate and form a conductor circuit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing ink and a forming method for forming a silver conductor circuit on various substrates used as electronic industrial materials.

[0002]

2. Description of the Related Art Conventionally, a screen printing method using a silver paste has been widely used for forming a silver conductor circuit on a substrate. Although this method is inexpensive and can produce a large amount of printed patterns, it has a drawback that it is difficult to form a fine pattern having a line / space of 50 μm. Further, in screen printing, since a screen mesh is used for the printing plate, there is a drawback that the positional accuracy is deteriorated because of positional deviation when printing on a large base material. Further, the offset printing using an alkyd resin or a rosin-based resin has a problem that the printed pattern has unevenness and is not smoothed.

On the other hand, a photolithography method is used as a method for forming a fine pattern. Although this method can form a fine fine pattern, it requires a large amount of equipment for manufacturing, and the process is complicated and time-consuming.
The production cost is high, and the product cannot be supplied at low cost.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned drawbacks of the conventional method. The offset for a silver conductor circuit contains a resin component, a solvent component, a metallic silver powder and, if necessary, a flux component. A method for offset printing a pattern on a substrate using a printing ink to provide a fine pattern forming method with high positional accuracy and high line / space resolution.

[0005]

The present invention provides a terpene polymer, a terpene phenol copolymer, an α-pinene polymer,
a resin of β-pinene polymer and a modified resin of the polymer,
The present invention relates to a silver conductor circuit printing ink containing at least one resin component selected from hydrogenated resins, a solvent component, a metallic silver powder and, if necessary, a flux component.

Further, the present invention provides at least one selected from the group consisting of terpene polymers, terpene phenol copolymers, α-pinene polymers, β-pinene polymer resins, modified resins of the above polymers and hydrogenated resins. Step of printing a pattern on a substrate using a printing ink for a silver conductor circuit containing a resin component, a solvent component, a metallic silver powder and optionally a flux component, the printing pattern as it is or / or an active energy ray A step of curing and / or smoothing by irradiation and / or heating, a step of printing the cured and / or smoothed printing pattern as it is / or overprinting with the same pattern, and a step of drying or baking. The present invention relates to a method for forming a silver conductor circuit.

The resin of the present invention is suitable for offset printing, and it is necessary to select a resin having smoothness. The terpene polymer, the terpene phenol copolymer, the α-pinene polymer and the β-pinene polymer should be selected. A resin, a modified resin of the above-mentioned polymer, a hydrogenated resin, and the like are preferable, and those which are used alone or in combination are used. The amount of resin varies depending on the content of silver, but it is preferably 3 to 40% in consideration of printability. or,
Since the resin has a lower decomposition temperature than the alkyd resin or the rosin resin, it has been found that the adhesion of the conductor is enhanced.

The solvent used in the present invention has the purpose of dissolving a solid resin or additive in a liquid state and the role of a thickener for lowering the viscosity. There are terpene-based solvents (gum turpentine oil, dipentene, limonene, terpinol), xylene, toluene, butanol, mineral spirits, petroleum-based solvents (solvesso, naphtha), etc. that are used to dissolve solid resins. Solvents 3-6 are used to lower.

The metallic silver powder is spherical with a particle size of 0.05 to 1.0 μm,
It is preferably monodispersed with a particle size of 0.1 to 0.7 μm. The flake powder is 0.1-10 μm, more preferably
0.5 to 5 μm is preferable, spherical ones are used alone, or flakes are 10% to 75%, preferably 20% in terms of silver.
Mix ~ 50%. The purity of the silver powder at this time is 95-99.9
Use 9%.

The particle size of the spherical silver powder is set to 0.05 to 1.0 μm because if the particle size is 0.05 μm or less, the particle size is too small and elasticity is not obtained, and printability is unsuitable. This is because the handling becomes difficult because of this. On the other hand, when the thickness is 1 μm or more, there is a problem that the ink cannot be uniformly deposited on the roller at the time of inking and stable printing cannot be performed.

The reason why the flaky powder is mixed with the spherical powder is that when the flakes are located on the line, the powder and powder can make a large contact with each other and the resistance of the conductor can be reduced.

The additive components of the present invention are a leveling agent, a polymerization initiator, an oxidation promoter, an anti-skinning agent, a thickener, a metal chelate resin, a dispersant and a filler, which are added depending on the suitability of the ink. For example, if it is a leveling agent, it is advisable to add 0.1 to several% of a silicon compound. Acrylic oligomers as polymerization initiators, cobalt naphthenate and manganese naphthenate as oxidation promoters, methyl ethyl ketone oxime as an anti-skinning agent, thickening varnishes and coupling agents as thickeners, and linseed oil fatty acid salts and stearic acid as metal chelate resins. Salt, oleate, etc. The filler is Al ₂
Fine powder of O ₃ , TiO ₂ , BiO ₂ , SnO ₂ or the like may be used, and powder of 0.05 μm to 10 μm or less may be used.
The filler is added for the purpose of removing or reducing the strain generated in the silver thin film or the interface between the silver and the substrate during firing. It also leads to improved chemical resistance.

The flux component is an organometallic compound and / or
Alternatively, it may be added with a glass frit. P as a metal component
b, B, Si, Zn, Bi, Sn, Cr, Mn, Ti,
Select one that contains Al, alkali, alkaline earth, etc. As the organic metal compound, 2-ethylhexanoate, naphthenate, neodecanoate, metal alkoxide, linseed oil fatty acid salt, oleate, stearate and the like are used.

The flux component is added for the purpose of improving the adhesion between the silver conductor thin film and the base material. For example, if the base material is a glass substrate, PbO-B ₂ O ₃ -SiO ₂ , Pb.
A glass frit having a softening point of about 350 to 600 ° C. may be used for the OB ₂ O ₃ —ZnO ₂ system, and SiO ₂ —Al ₂ O ₃ —CaO and SiO ₂ —PbO—Ca for an alumina substrate.
O-based glass frit having a high softening point may be used.

The above-mentioned resin, solvent, additives, metallic silver powder and, if necessary, flux components are premixed and then melted and kneaded by a triple roll until they are sufficiently homogeneous. A predetermined pattern is obtained by offset printing using the printing ink for a silver conductor circuit thus adjusted.

The method for printing the predetermined pattern is offset printing, which may be either a planographic printing plate or an intaglio printing plate, and the predetermined pattern is obtained by transferring the ink from the printing plate to the blanket or from the blanket to the substrate.

When the ink transfer of the predetermined pattern is not sufficiently performed once, the overprinting may be performed. By performing this overprinting, the total amount of ink transfer and the film thickness can be increased. You can continue overprinting, but
In the case of overprinting, if the transfer amount does not increase due to backtrapping, backtrapping can be prevented by curing the ink on the pattern before overprinting. Irradiation with active energy rays and / or curing method
Alternatively, it can be cured by heating. Further, at this time, leveling also promotes smoothing of the pattern.
Active energy rays mean ultraviolet rays, infrared rays, and electron rays,
By combining these active energy rays and heating, curing and / or smoothing proceed. To further accelerate the curing, it is advisable to add an ultraviolet curable resin, a polymerization initiator and an oxidation accelerator.

The pattern obtained by offset printing is subjected to a drying process. The drying temperature and time are not particularly specified, but the printing surface can be sufficiently dried at a drying temperature of 60 ° C to 200 ° C.

When a printing ink for a silver conductor circuit containing a flux component is used, the predetermined pattern obtained by offset printing is subjected to a firing process. The firing temperature is the temperature at which the organic substances contained in the resin component, solvent component, additive component, etc. must evaporate, sublime, or decompose.
It is desired that the temperature is 00 ° C or higher. Further, in order to improve the adhesion between silver and the base material, the flux component must be melted and a reaction phase must be formed at the interface with the base material, and the temperature must be raised to the temperature required for melting and baked. ..

Production Example 1 Terpene polymer resin (Yasuhara Chemical Co., Ltd .: YS
Resin PX300) 20 g, 0.3 μm spherical metallic silver powder 80 g
Was premixed and then kneaded with a triple roll to prepare a silver ink.

Production Example 2 To 14.5 g of a terpene phenol copolymer resin (YS Hara Chemical Co., Ltd .: YS Polystar T30), 85 g of 0.3 μm spherical metallic silver powder and 0.5 g of No. 5 solvent were added to prepare an ink.

Production Example 3 β-pinene polymer resin (Yasuhara Chemical Co., Ltd .: Y
S resin PXN300N) (13 g) was mixed with 0.8 g of spherical metallic silver powder (85 g), No. 5 solvent (0.5 g), methyl ethyl ketone oxime (1 g) and cobalt naphthenate (0.5 g) and kneaded to prepare an ink.

Production Example 4 α-pinene polymer resin (Yasuhara Chemical Co., Ltd .: Y
S Resin A 800) 0.1 gm spherical metallic silver powder 75 g in 75 g
g, No. 5 solvent 0.5 g, methyl ethyl ketone oxime 1 g, and thickening varnish 3.5 g were kneaded to prepare an ink.

Production Example 5 13 g of a terpene polymer resin (Dimaron manufactured by Yasuhara Chemical Co., Ltd.), 20 g of chloroform and 6 g of No. 5 solvent.
Is added to dissolve rosin, and then chloroform is removed under reduced pressure. 1 g of methyl ethyl ketone oxime on 40 g of 0.3 μm spherical metallic silver powder and 40 g of 5 μm flaky silver powder.
Were mixed and kneaded to prepare an ink.

Production Example 6 20 g of aromatic modified terpene polymer resin and 20 g of terpene-based hydrogenated resin (Yasuhara Chemical Co., Ltd .: YS Resin TO)
115, chloralon M), 1 g of a polymerization initiator (acrylic oligomer), 4 g of methyl ethyl ketone, 45 g of 0.3 μm spherical metallic silver powder and 15 g of 8 μm flake silver powder were mixed and kneaded to prepare an ink.

Production Example 7 To 16 g of an alkyd resin (manufactured by Dainippon Ink and Chemicals, Inc .: Beccosol EL-8001), 80 g of 0.3 μm spherical metallic silver powder and 4 g of a glass frit (1350 manufactured by Asahi Glass Co., Ltd.) were premixed, and then three-rolled. And kneaded to prepare ink.

[0027]

Conventional Example 1 As a resin component, 7.5 g of ethyl cellulose was dissolved in 7.5 g of methyl isobutyl ketone, 80 g of spherical metal silver powder having a size of 0.3 μm and 5 g of α-terpinol were added, premixed, and then homogenized with a three-roll mill. Kneaded thoroughly until 50cm x 50cm using this silver paste
Screen printing (325 mesh) was performed once on the glass substrate.

As a result, the pattern of 30 μm lines / spaces is contacted with the lines adjacent to the whole and is printed solidly.
It wasn't resolved at all. At the line / space of 50 μm, it was in contact with the adjacent line in some parts and short-circuited. All were resolved at 100 μm line / space. As a result of measuring the displacement of the pattern printed on the glass substrate, there was a displacement of +180 μm in the vertical direction and +80 μm in the horizontal direction with respect to the printing direction of 50 cm × 50 cm. At this time, the membrane pressure was 20 μm and the sheet resistance was 40 mΩ / □.

[0029]

PRIOR ART EXAMPLE 2 After printing four times with the ink of Production Example 7, ultraviolet rays are irradiated for 1 minute. Similarly, printing was repeated 4 times and UV irradiation was repeated, and printing was performed 20 times in total. As a result of printing, the line / space of 30 μm was resolved, and the positional deviation in the vertical and horizontal directions was 5 μm or less. However, the smoothness of the printed pattern was not obtained.

[0030]

[Example 1] Using the ink of Production Example 1 on a glass substrate
A predetermined pattern of 50 cm × 50 cm was subjected to offset printing four times by overprinting and dried at 150 ° C. for 10 minutes. As a result, a line / space resolution of 30 μm was found. The positional deviation in the vertical and horizontal directions was ± 5 μm or less.

[0031]

[Example 2] After printing four times with the ink of Production Example 1, irradiation with ultraviolet rays was performed for 1 minute. Similarly, printing was repeated 4 times and UV irradiation was repeated, and printing was performed 20 times in total. Then, after drying at 150 ° C. for 10 minutes, the line / space of 30 μm was resolved.
The positional deviation in the vertical and horizontal directions was ± 5 μm or less.

[0032]

[Example 3] After printing four times using the ink of Production Example 2, after irradiating with ultraviolet rays for 1 minute, printing was repeated four times and irradiation with ultraviolet rays was repeated in the same manner to print 20 times in total. As a result, the smoothing of the pattern progressed. The 30 μm line / space was resolved. The positional deviation in the vertical and horizontal directions was 5 μm or less.

[0033]

[Examples 4 to 7] The results of performing the same operations as above are shown in Table 1.
I wrote it in.

[0034]

[Table 1]

Production Example 8 Terpene polymer resin (YSHARA CHEMICAL CO., LTD .: YS
Resin PX300) 20 g, 0.3 μm spherical metallic silver powder 80
g was premixed and then kneaded with a triple roll to prepare a silver ink.

Production Example 9 To 16 g of a terpene phenol copolymer resin (YS Polystar T30 manufactured by Yasuhara Chemical Co., Ltd.), 80 g of 0.3 μm spherical metallic silver powder, and 4 g of glass frit (1350 manufactured by Asahi Glass Co., Ltd.)
g was premixed and then kneaded with a triple roll to prepare a silver ink.

Production Example 10 β-pinene polymer resin (Yasuhara Chemical Co., Ltd .: Y)
S resin PXN300N) 10g, 0.3μm spherical metallic silver powder
Ink was prepared by mixing 85 g, 4.5 g of glass frit (1370 manufactured by Asahi Glass) and 0.5 g of No. 5 solvent and kneading.

Production Example 11 α-pinene polymer resin (Yasuhara Chemical Co., Ltd .: Y)
S Resin A800) 0.5 gm spherical metallic silver powder 85 g on 10 g
g, No. 5 solvent 0.5 g, methyl ethyl ketone oxime 1 g, cobalt naphthenate 0.5 g, and glass frit (Asahi Glass: 1307) 3.5 g were mixed and kneaded to prepare an ink.

Production Example 12 15 g of a terpene polymer resin (manufactured by Yasuhara Chemical Co., Ltd .: Daimaron), 75 g of 0.1 μm spherical metallic silver powder, 0.5 g of No. 5 solvent, 1 g of eugenol, 3.5 g of thickening varnish, 2.5 g of bismuth octylate, octyl. 2.5 g of lead acid was mixed and kneaded to prepare an ink.

Production Example 13 80 g of 0.3 μm spherical metallic silver powder and 15 g of glass frit (Asahi Glass: 1350) per 15 g of aromatic modified terpene polymer resin (YS Hara Chemical Co., Ltd .: YS resin TO115) 3
g, bismuth octylate 1.5 g, as filler 0.5 g
Were mixed and kneaded to prepare an ink.

Production Example 14 Terpene-based hydrogenated resin (Yasuhara Chemical Co., Ltd .: Floorlon M) dissolved in No. 5 solvent 6 g
40 g of 0.3 μm spherical metallic silver powder, 40 g of 5 μm flake-shaped silver powder, 1 g of methyl ethyl ketone oxime, and 3 g of glass frit (manufactured by Asahi Glass: 1350) were mixed and kneaded to prepare an ink.

Production Example 15 α-pinene polymer resin (Yasuhara Chemical Co., Ltd .: Y)
S resin A800) 15 g, 0.3 μm spherical metal powder 80 g,
3 g of glass frit (manufactured by Asahi Glass: 1581), 1.5 g of bismuth naphthenate and 0.5 g of alumina filler were mixed and kneaded to prepare an ink.

Production Example 16 16 g of alkyd resin (manufactured by Dainippon Ink and Chemicals, Inc .: Beckosol EL-8001) was premixed with 80 g of spherical metal silver powder of 0.3 μm and 4 g of glass frit (1350 manufactured by Asahi Glass Co., Ltd.). Kneading was performed to prepare an ink.

[0044]

Conventional Example 3 As a resin component, 7.5 g of ethyl cellulose is dissolved in 7.5 g of methyl isobutyl ketone, 75 g of spherical metallic silver powder of 0.3 μm, 5 g of α-terpineol and Pb.
1 μm glass frit 5 of OB ₂ O ₃ —SiO ₂ system
g was added and premixed, and then thoroughly kneaded with a three-roll mill until homogenous. With this silver paste,
Screen printing (325 mesh) was performed once on a 50 cm × 50 cm glass substrate. The glass substrate on which this predetermined pattern was printed was baked in an electric furnace. The firing profile at this time was such that the temperature was raised to 550 ° C. in 30 minutes, held for 10 minutes, and then cooled in 1 hour. As a result of measuring the displacement of the pattern printed on the glass substrate, it is +180 μm in the vertical direction and +80 in the horizontal direction.
There was a displacement of μm. At this time, the membrane pressure was 10 μm and the sheet resistance was 2 μmΩ / □.

As a result, the pattern of the line 1 space of 30 μm was in contact with the line adjacent to the whole and was printed solidly and was not resolved at all.

[0046]

[Comparative Example 1] Using the ink of Production Example 8 on a glass substrate
As a result of performing offset printing by overprinting a predetermined pattern of 50 cm × 50 cm four times, a line / space of 30 μm was resolved. The positional deviation in the vertical and horizontal directions was +5 μm or less. This glass substrate was fired at 550 ° C. as in the conventional example. As a result, the resolution and displacement of the line / space of 30 μm were similar. However, the adhesion was weak enough to peel off in the tape peel test. The sheet resistance is 25m
It was Ω / □.

[0047]

[Comparative Example 2] The ink of Production Example 16 was printed four times and then irradiated with ultraviolet rays for 1 minute. Similarly, printing was repeated 4 times and UV irradiation was repeated to print 20 times in total. As a result of firing at 550 ° C. for 10 minutes, the line / space of 30 μm was resolved, and the positional deviation in the vertical and horizontal directions was +5 μm or less.

[0048]

Example 8 The same operation as in Comparative Example 1 was performed using the ink of Production Example 9. As a result of firing, resolution of 30 μm line / space was confirmed and the positional deviation was 5 μm or less.
Adhesion did not come off in the tape peel test.

[0049]

[Example 9] The ink of Production Example 9 was printed four times and then irradiated with ultraviolet rays for 1 minute. Similarly, printing was repeated 4 times and UV irradiation was repeated, and printing was performed 20 times in total. As a result of firing at 550 ° C. for 10 minutes, the line / space of 30 μm was resolved, and the positional displacement in the vertical and horizontal directions was +5 μm or less.

[0050]

[Example 10] After printing four times with the ink of Production Example 10 and irradiating with ultraviolet rays for 1 minute, printing was repeated four times and irradiation with ultraviolet rays was repeated in the same manner to print a total of 20 times. The 30 μm line / space was resolved. The length and width were each 5 μm or less. As a result of baking this glass substrate at 550 ° C. for 10 minutes,
The resolution was up to a line / space of 30 μm, and the positional accuracy was 20 μm or less as before firing. Sheet resistance
The adhesion was good at 12 μm.

[0051]

[Examples 11-14] Table 2 shows the results of the same operations as above.
I wrote it in.

[0052]

Example 15 The ink of Production Example 15 was used to print on an alumina substrate of 50 × 50 μm four times, after which it was irradiated with ultraviolet rays for 2 minutes and then repeatedly printed 20 times. This printed alumina substrate
It was calcined at 650 ° C. The 30 μm line / space was resolved. The positional deviation in the vertical and horizontal directions was 5 μm or less. The results are shown in Table 2.

[0053]

[Table 2]

[0054]

According to the method of the present invention, it is possible to easily obtain a smooth predetermined pattern by offset printing, and it is possible to create a print pattern having high resolution, adhesion and positional accuracy.

Claims (15)

[Claims] 1. At least one resin component selected from a terpene polymer, a terpene phenol copolymer, an α-pinene polymer, a β-pinene polymer resin, a modified resin of the polymer, and a hydrogenated resin, A printing ink for a silver conductor circuit, which contains a solvent component and metallic silver powder. 2. The printing ink for silver conductor circuits according to claim 1, which further contains a flux component. 3. The method according to claim 1, further comprising one or more of a leveling agent, a polymerization initiator, an oxidation accelerator, an anti-skinning agent, a thickener, a metal chelate resin and a dispersant. Item 2. A printing ink for a silver conductor circuit according to item 2. 4. The silver according to claim 1, wherein the metallic silver powder is a spherical powder having a particle size of 0.05 to 1.0 μm and / or a flake powder having a particle size of 0.5 to 5 μm. Printing ink for conductor circuits. 5. A resin of a terpene polymer, a terpene phenol copolymer, an α-pinene polymer, a β-pinene polymer and a modified resin of the polymer, or at least one resin component selected from hydrogenated resins, A step of printing a pattern on a substrate using a printing ink for a silver conductor circuit containing a solvent component and a metallic silver powder, curing and / or smoothing the printed pattern as it is / or by irradiation with active energy rays and / or heating. Process of curing, curing and / or
Alternatively, a method of forming a silver conductor circuit, comprising a step of overprinting a smoothed print pattern as it is or the same pattern, and a step of drying. 6. The method for forming a silver conductor circuit according to claim 5, wherein the metallic silver powder is a spherical powder having a particle diameter of 0.05 to 1.0 μm and / or a flake powder having a particle diameter of 0.5 to 5 μm. 7. The printing ink for silver conductor circuits according to claim 2, 3 or 4, wherein the flux component is an organic metal compound and / or a glass frit. 8. The method for forming a silver conductor circuit according to claim 5, wherein the active energy rays are one or more of ultraviolet rays, infrared rays, and electron rays. 9. A printing ink for a silver conductor circuit comprises a leveling agent, a polymerization initiator, an oxidation accelerator, an anti-skinning agent, a thickener,
The method for forming a silver conductor circuit according to claim 5, 6, or 8, containing one or more of a metal chelate resin and a dispersant. 10. A resin component of a terpene polymer, a terpene phenol copolymer, an α-pinene polymer, a β-pinene polymer and a modified resin of the polymer, and at least one resin component selected from hydrogenated resins, A step of printing a pattern on a substrate using a printing ink for a silver conductor circuit containing a solvent component, a metallic silver powder and a flux component, and curing the printed pattern as it is / or by irradiation with active energy rays and / or heating. A method for forming a silver conductor circuit, which comprises a step of squeezing, a step of overprinting a cured print pattern as it is or with the same pattern, and a step of firing. 11. The method for forming a silver conductor circuit according to claim 10, wherein the firing temperature is 200 ° C. or higher. 12. The method for forming a silver conductor circuit according to claim 10, wherein the metallic silver powder is a spherical powder having a particle size of 0.05 to 1.0 μm and / or a flake powder having a particle size of 0.5 to 5 μm. 13. The active energy ray is an ultraviolet ray, an infrared ray,
The method for forming a silver conductor circuit according to claim 10, 11 or 12, which is one or more kinds of electron beams. 14. A printing ink for a silver conductor circuit further comprises one or more of a leveling agent, a polymerization initiator, an oxidation accelerator, an anti-skinning agent, a thickener, a metal chelate resin, a dispersant and a filler. Claims 10 and 1 containing
The method for forming a silver conductor circuit according to claim 1, claim 12, or claim 13. 15. The method according to claim 10, wherein the flux component is an organometallic compound and / or a glass frit.
The method for forming a silver conductor circuit according to claim 12, claim 13 or claim 14.