JP2010151889A - Positive photosensitive paste - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a positive photosensitive paste which enables to stably form an inorganic fine pattern. <P>SOLUTION: The positive photosensitive paste includes organic components and an inorganic powder, wherein the positive photosensitive paste includes at least an alkali-soluble resin, a photoacid generator and a hindered phenol compound as the organic components. Alternatively, the positive photosensitive paste includes organic components and an inorganic powder, wherein the positive photosensitive paste includes a resin in which an alkali-soluble group is protected by a group which is eliminated under acid and a photoacid generator, or a resin in which an alkali-soluble group is protected by a group which is eliminated under alkali and a photobase generator, and further includes a hindered phenol compound. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a positive photosensitive paste that makes it possible to stably form an inorganic fine pattern. The positive photosensitive paste of the present invention is used for electronic parts and displays.

  Conventionally, as a method for forming a pattern of an inorganic material, it has been often proposed to use a negative photosensitive paste (for example, Patent Document 1). However, since the negative photosensitive paste contains a large amount of a crosslinking agent, there is a problem in that a baking shrinkage force acts on the crosslinking agent and pattern defects such as pattern peeling and disconnection are likely to occur. . Furthermore, particularly when the negative photosensitive paste contains a large amount of light-shielding conductive powder, such as a conductive paste for forming a conductive pattern, the exposure light does not reach the bottom of the coating film, and the coating film There was a problem that the developing solution resistance of the lower part was lowered, and the pattern lower part and edge curl were generated, and a conductive pattern with a thick film could not be formed.

As a method for solving these problems, it has been proposed to use a positive photosensitive paste (for example, Patent Documents 2 and 3). Further, on page 10 of Patent Document 2, it is proposed to add a phenol compound, an organic acid, or the like in order to enhance solubility in a developer. However, as a result of further trials by the present inventors, the effect of shortening the development time could be confirmed, but the development margin was narrow and not practically used.
JP-A-1-296534 JP 2004-110019 A JP 2006-108072 A

  The present invention provides a positive photosensitive paste that makes it possible to stably form an inorganic fine pattern.

  The present invention relates to a positive photosensitive paste containing an organic component and an inorganic powder, and includes at least an alkali-soluble resin, a photoacid generator, and a hindered phenol compound as organic components. It is.

  Further, it is a positive photosensitive paste containing an organic component and an inorganic powder, in which an alkali-soluble group is protected with an acid-eliminating group and a photoacid generator, or an alkali-soluble group is removed with an alkali. A positive photosensitive paste comprising a resin protected with a releasing group and a photobase generator, and further comprising a hindered phenol compound.

  ADVANTAGE OF THE INVENTION According to this invention, the positive photosensitive paste which makes it possible to form the inorganic fine pattern stably can be provided.

  The positive photosensitive paste of the present invention is a positive photosensitive paste containing an organic component and an inorganic powder, and contains at least an alkali-soluble resin, a photoacid generator, and a hindered phenol compound as the organic component, or A resin in which an alkali-soluble group is protected with an acid-eliminating group, a photoacid generator, a hindered phenol compound, a resin in which an alkali-soluble group is protected with an alkali-eliminating group, It is necessary to contain a photobase generator and a hindered phenol compound.

  The alkali-soluble resin used in the present invention is not particularly limited as long as the part exposed at the time of development is alkali-soluble and can be eluted into an alkali developer, but it is preferable to mainly use an acrylic resin and a novolac resin. it can.

  As the acrylic resin, for example, an acrylic resin obtained by polymerizing hydroxystyrene, acrylic acid, methacrylic acid, maleic acid and derivatives thereof, which are monomers having an alkali-soluble group, can be used. In addition, alkali-soluble monomers and alkali-insoluble acrylic acid esters, methacrylic acid esters, maleic acid esters, hydroxystyrene esters, styrene, vinyl alcohol, vinyl acetate, vinyl esters, and derivatives thereof remain alkali-soluble. Copolymerization may be performed within a range of dripping. When the alkali-soluble resin is polyhydroxystyrene, specifically, o-hydroxystyrene, m-hydroxystyrene, p-hydroxystyrene, 2- (o-hydroxyphenyl) propylene, 2- (m-hydroxyphenyl) propylene A polymer obtained by polymerizing hydroxystyrenes such as 2- (p-hydroxyphenyl) propylene alone or in combination in the presence of a radical polymerization initiator, an anionic polymerization initiator or a cationic polymerization initiator can be used.

  In addition, after polymerization, a hydrogenated product may be used in order to reduce the absorbance of the resin and improve the pattern processability. When using an acrylic resin, a preferable weight average molecular weight is 5,000-100,000 in polystyrene conversion, More preferably, it is 5,000-20,000.

  A novolak resin is also preferably used as the resin used in the present invention. The novolak resin can be obtained by polycondensation of various phenols alone or a mixture of a plurality of them with aldehydes such as formaldehyde and paraformaldehyde at 80 to 200 ° C. In addition, polymers obtained by partially etherifying or partially esterifying these polymers can also be used.

  Examples of phenols constituting the novolak resin include phenol, p-cresol, m-cresol, o-cresol, 2,3-dimethylphenol, 2,4-dimethylphenol, 2,5-dimethylphenol, 2,6- Dimethylphenol, 3,4-dimethylphenol, 3,5-dimethylphenol, 2,3,4-trimethylphenol, 2,3,5-trimethylphenol, 3,4,5-trimethylphenol, 2,4,5- Trimethylphenol, methylene bisphenol, methylene bis p-cresol, resorcin, catechol, 2-methyl resorcin, 4-methyl resorcin, o-chlorophenol, m-chlorophenol, p-chlorophenol, 2,3-dichlorophenol, m-methoxy Phenol, p-methoxy Enol, p-butoxyphenol, o-ethylphenol, m-ethylphenol, p-ethylphenol, 2,3-diethylphenol, 2,5-diethylphenol, p-isopropylphenol, α-naphthol, β-naphthol, etc. These can be used alone or as a mixture of two or more. Examples of aldehydes include formaldehyde, paraformaldehyde, acetaldehyde, benzaldehyde, hydroxybenzaldehyde, chloroacetoaldehyde, and the like. These can be used alone or as a mixture of a plurality of them.

  As the novolak resin of the present invention, for example, a product obtained by condensation polymerization of the above-mentioned mixture of phenols and aldehydes under an acid catalyst can be used.

  The preferred weight average molecular weight of the novolak resin used in the photosensitive resin composition of the present invention is 1,000 to 100,000, more preferably 1,500 to 25,000, and even more preferably 4,000 to 10 in terms of polystyrene. , 000.

  In the present invention, a resin in which an alkali-soluble group is protected with a group capable of leaving with an acid or an alkali can also be used. When such a resin is used, a non-exposed portion is not dissolved in the developer, so that a large contrast can be obtained.

  As the resin in which the alkali-soluble group used in the present invention is protected with an acid or a group capable of leaving with an alkali, an acid generated from a photoacid generator or an alkali generated from a photobase generator at the time of exposure, Although it will not specifically limit if it remove | eliminates by the heating after exposure and reproduces | regenerates an alkali-soluble group, For example, a methoxymethyl group, 1-methoxyethyl group, 1-methoxypropyl group, 1-methoxybutyl group, 1-ethoxy Carbonate such as acetal group such as ethyl group, 1-ethoxypropyl group, 1-ethoxybutyl group, tetrahydrofuranyl group, tetrahydropyranyl group, ketal group such as 1-methoxy-1-methylethyl group, and t-butoxycarbonyl group Such as an ester group. Of these, an acetal group is particularly preferably used. The protection of the alkali-soluble group does not need to be performed for all of the resin, and it is preferable to protect 10 to 100 mol% of the entire alkali-soluble group. It is also possible to mix 1 to 100 parts by weight of unprotected resin with 100 parts by weight of protected resin. By including such an unprotected group or resin, the sensitivity can be increased.

  The preferred weight average molecular weight of the resin in which the alkali-soluble group is protected with an acid or an alkali-eliminating group is 1,000 to 100,000, more preferably 3,000 to 50,000, still more preferably in terms of polystyrene. Is 10,000 to 30,000.

  Examples of the photoacid generator used in the present invention include onium salts, halogen-containing compounds, diazomethane compounds, sulfone compounds, sulfonic acid ester compounds, sulfonimide compounds, and diazo ketone compounds.

  Specific examples of the onium salt include diazonium salt, ammonium salt, iodonium salt, sulfonium salt, phosnium salt, oxonium salt and the like. Preferred onium salts include diphenyliodonium triflate, diphenyliodonium pyrenesulfonate, diphenyliodonium dodecylbenzenesulfonate, triphenylsulfonium triflate, triphenylsulfonium hexafluoroantimonate, triphenylsulfonium naphthalenesulfonate, (hydroxyphenyl) benzylmethylsulfonium toluenesulfonate Etc.

  Specific examples of the halogen-containing compound include haloalkyl group-containing hydrocarbon compounds and haloalkyl group-containing heterocyclic compounds. Preferred halogen-containing compounds include 1,1-bis (4-chlorophenyl) -2,2,2-trichloroethane, 2-phenyl-4,6-bis (trichloromethyl) -s-triazine, and 2-naphthyl-4,6. -Bis (trichloromethyl) -s-triazine and the like can be mentioned.

  Specific examples of the diazomethane compound include bis (trifluoromethylsulfonyl) diazomethane, bis (cyclohexylsulfonyl) diazomethane, bis (phenylsulfonyl) diazomethane, bis (p-tolylsulfonyl) diazomethane, and bis (2,4-xylyl). Sulfonyl) diazomethane, bis (p-chlorophenylsulfonyl) diazomethane, methylsulfonyl-p-toluenesulfonyldiazomethane, cyclohexylsulfonyl (1,1-dimethylethylsulfonyl) diazomethane, bis (1,1-dimethylethylsulfonyl) diazomethane, phenylsulfonyl ( And benzoyl) diazomethane.

  Specific examples of the sulfone compound include β-ketosulfone compounds and β-sulfonylsulfone compounds. Preferred compounds include 4-trisphenacyl sulfone, mesityl phenacyl sulfone, bis (phenylsulfonyl) methane, and the like.

  Examples of the sulfonate compound include alkyl sulfonate, haloalkyl sulfonate, aryl sulfonate, imino sulfonate, and the like. Specific examples of the sulfonic acid compound include benzoin tosylate, pyrogallol trimesylate, nitrobenzyl-9,10-diethoxyanthracene-2-sulfonate, and the like.

  Specific examples of the sulfonimide compound include N- (trifluoromethylsulfonyloxy) succinimide, N- (trifluoromethylsulfonyloxy) phthalimide, N- (trifluoromethylsulfonyloxy) diphenylmaleimide, N- (trifluoromethyl). Sulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxylimide, N- (trifluoromethylsulfonyloxy) -7-oxabicyclo [2.2.1] hept-5 Ene-2,3-dicarboxylimide, N- (trifluoromethylsulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy-2,3-dicarboxylimide, N- (trifluoromethylsulfonyl) Oxy) naphthyl dicarboxylimide, N- (camphorsulfur Nyloxy) succinimide, N- (camphorsulfonyloxy) phthalimide, N- (camphorsulfonyloxy) diphenylmaleimide, N- (camphorsulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxyl Imido, N- (camphorsulfonyloxy) -7-oxabicyclo [2.2.1] hept-5-ene-2,3-dicarboxylimide, N- (camphorsulfonyloxy) bicyclo [2.2.1] Heptane-5,6-oxy-2,3-dicarboxylimide, N- (camphorsulfonyloxy) naphthyl dicarboxylimide, N- (4-methylphenylsulfonyloxy) succinimide, N- (4-methylphenylsulfonyloxy) Phthalimide, N- (4-methylpheny Sulfonyloxy) diphenylmaleimide, N- (4-methylphenylsulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxylimide, N- (4-methylphenylsulfonyloxy) -7 -Oxabicyclo [2.2.1] hept-5-ene-2,3-dicarboxylimide, N- (4-methylphenylsulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy- 2,3-dicarboxylimide, N- (4-methylphenylsulfonyloxy) naphthyl dicarboxylimide, N- (2-trifluoromethylphenylsulfonyloxy) succinimide, N- (2-trifluoromethylphenylsulfonyloxy) phthalimide N- (2-trifluoromethylphenylsulfonyloxy) diphe Nilmaleimide, N- (2-trifluoromethylphenylsulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxylimide, N- (2-trifluoromethylphenylsulfonyloxy)- 7-oxabicyclo [2.2.1] hept-5-ene-2,3-dicarboxylimide, N- (2-trifluoromethylphenylsulfonyloxy) bicyclo [2.2.1] heptane-5,6 -Oxy-2,3-dicarboximide, N- (2-trifluoromethylphenylsulfonyloxy) naphthyl dicarboxylimide, N- (4-fluorophenylsulfonyloxy) succinimide, N- (2-fluorophenylsulfonyloxy) Phthalimide, N- (4-fluorophenylsulfonyloxy) diphenylmale N- (4-fluorophenylsulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxylimide, N- (4-fluorophenylsulfonyloxy) -7-oxabicyclo [ 2.2.1] Hept-5-ene-2,3-dicarboximide, N- (4-fluorophenylsulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy-2,3- Examples thereof include dicarboxylimide and N- (4-fluorophenylsulfonyloxy) naphthyl dicarboxylimide.

  Specific examples of the diazoketone compound include 1,3-diketo-2-diazo compounds, diazobenzoquinone compounds, diazonaphthoquinone compounds, and the like.

From the viewpoint of pattern formation and low firing residue, diazonaphthoquinone compounds are particularly preferably used as photoacid generators, among which 1,2-naphthoquinonediazide-4-sulfonic acid and 2,3,4,4 Esters with '-tetrahydroxybenzophenone, esters of 1,2-naphthoquinonediazide-4-sulfonic acid with 1,1,1-tris (4-hydroxyphenyl) ethane, tetrahydroxybenzophenone and 2-diazo-1-naphthoquinone An ester with -5-sulfonic acid, bis (cyclohexylsulfonyl) diazomethane and the like can be further exemplified as preferred compounds. '
One type of photoacid generator that can be used in the present invention may be used alone, or a mixture of two or more types may be used. The mixing ratio of the photoacid generator is preferably 2 to 50 parts by mass, more preferably 100 parts by mass with respect to 100 parts by mass of the resin in which the alkali-soluble resin or the alkali-soluble group is protected with an acid or an alkali. Is blended at a ratio of 10 to 40 parts by mass. High contrast is achieved by setting the concentration of the photoacid generator to 2 parts by mass or more, and sensitivity can be kept high by setting it to 50 parts by mass or less.

  Examples of the photobase generator preferably used in the present invention include transition metal complexes, orthonitrobenzyl carbamates, α, α-dimethyl-3,5-dimethoxybenzyl carbamates, acyloxyiminos and the like.

  Transition metal complexes include bromopentammonium cobalt perchlorate, bromopentamethylamine cobalt perchlorate, bromopentapropylamine cobalt perchlorate, hexaammonium cobalt perchlorate, hexamethylamine cobalt perchlorate Salt, hexapropylamine cobalt perchlorate and the like.

  Orthonitrobenzyl carbamates include [[(2-nitrobenzyl) oxy] carbonyl] methylamine, [[(2-nitrobenzyl) oxy] carbonyl] propylamine, [[(2-nitrobenzyl) oxy] carbonyl. ] Hexylamine, [[(2-nitrobenzyl) oxy] carbonyl] cyclohexylamine, [[(2-nitrobenzyl) oxy] carbonyl] aniline, [[(2-nitrobenzyl) oxy] carbonyl] piperidine, bis [[ (2-Nitrobenzyl) oxy] carbonyl] hexamethylenediamine, bis [[(2-nitrobenzyl) oxy] carbonyl] phenylenediamine, bis [[(2-nitrobenzyl) oxy] carbonyl] toluenediamine, bis [[( 2-Nitrobenzyl) oxy] carbo Ru] diaminodiphenylmethane, [[(2,6-dinitrobenzyl) oxy] carbonyl] methylamine, [[(2,6-dinitrobenzyl) oxy] carbonyl] propylamine, [[(2,6-dinitrobenzyl) oxy ] Carbonyl] butylamine, [[(2,6-dinitrobenzyl) oxy] carbonyl] hexylamine, [[(2,6-dinitrobenzyl) oxy] carbonyl] aniline, bis [[(2,6-dinitrobenzyl) oxy ] Carbonyl] ethylenediamine, bis [[(2,6-dinitrobenzyl) oxy] carbonyl] hexamethylenediamine, bis [[(2,6-dinitrobenzyl) oxy] carbonyl] phenylenediamine, and the like.

  Examples of α, α-dimethyl-3,5-dimethoxybenzylcarbamate include [[(α, α-dimethyl-3,5-dimethoxybenzyl) oxy] carbonyl] methylamine, [[(α, α-dimethyl-3. , 5-dimethoxybenzyl) oxy] carbonyl] propylamine, [[(α, α-dimethyl-3,5-dimethoxybenzyl) oxy] carbonyl] butylamine, [[(α, α-dimethyl-3,5-dimethoxybenzyl). ) Oxy] carbonyl] hexylamine, [[(α, α-dimethyl-3,5-dimethoxybenzyl) oxy] carbonyl] cyclohexylamine, [[(α, α-dimethyl-3,5-dimethoxybenzyl) oxy] carbonyl Aniline, [[(α, α-dimethyl-3,5-dimethoxybenzyl) oxy] carbonyl] piperidine, [[(Α, α-dimethyl-3,5-dimethoxybenzyl) oxy] carbonyl] ethylenediamine, bis [[(α, α-dimethyl-3,5-dimethoxybenzyl) oxy] carbonyl] hexamethylenediamine, bis [ And [(α, α-dimethyl-3,5-dimethoxybenzyl) oxy] carbonyl] phenylenediamine.

  Acyloxyiminos include propionyl acetophenone oxime, propionyl benzophenone oxime, propionyl acetone oxime, butyryl acetophenone oxime, butyryl acetone oxime, adipoyl acetophenone oxime, adipoyl acetone oxime, acryloyl acetophenone oxime, alloyl benzophenone oxime, Examples include acroyl acetone oxime.

  One type of photobase generator that can be used in the present invention may be used alone, or a mixture of two or more types may be used. The mixing ratio of the photobase generator is preferably 2 to 50 parts by weight, more preferably 10 to 40 parts by weight based on 100 parts by weight of the resin in which the alkali-soluble group is protected with an acid or an alkali-eliminating group. It mix | blends in the ratio of a mass part. High contrast is achieved by setting the concentration of the photobase generator to 2 parts by weight or more, and sensitivity can be kept high by setting it to 50 parts by weight or less.

  In general, when a wiring such as an electronic component or a display is manufactured using a photosensitive conductive paste, it is desired that development time is fast in order to improve productivity. When a phenol compound as exemplified in Patent Document 2 is used, the development time can be increased, but the development margin becomes narrow and cannot be put to practical use. A narrow development margin means a state in which the exposed portion is dissolved and the pattern is peeled off when developing for a longer time than the desired resolution is obtained, and the desired resolution cannot be obtained. In order to improve the uniformity within the substrate surface, it is desired that the pattern does not peel off even if developed for a long time (the development margin is wide). The present inventors have obtained the knowledge that by using a hindered phenol compound, the development time can be shortened while maintaining the development margin, and the present invention has been achieved.

  Specific examples of the hindered phenol compound in the present invention include 2,6-di-tert-butyl-4-methylphenol, 2,6-di-tert-butyl-4-ethylphenol, and 2,6-di-tert. -Butyl-4-butylphenol, 2-tert-butyl-4-methoxyphenol, 6-tert-butyl-2,4-methylphenol, 2-tert-butyl-4-ethylphenol, n-octadecyl-3- (3 , 5-di-tert-butyl-4-hydroxyphenyl) propionate, dioctadecyl-4-hydroxy-3,5-di-tert-butylbenzyl phosphonate, diethyl-4-hydroxy-3,5-di-tert -Butyl benzyl phosphonate, 6- (4-oxy-3,5-di-tert-butyl alinino)- , 4-Bis- (n-octylthio) -1,3,5-triazine, 4,4′-methylenebis (6-tert-butylphenol), 4,4′-methylenebis (2,6-di-tert-butylphenol) 4,4′-thiobis (6-tert-butyl-o-cresol), 4,4′-thiobis (3-methyl-6-tert-butylphenol), 2,2′-methylenebis (4-methyl-6- tert-butylphenol), 2,2′-thiobis (6-butyl-4-methylphenol), 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4- Hydroxybenzoyl) benzene, tris- (2-methyl-4-hydroxy-5-tert-butyl-phenol) butane, 1,6-bis (3,5-di-tert-butyl) -4-hydroxy-2-methylphenyl) butane, 1,1,3-tris (5-tert-butyl-4-hydroxy-2-methylphenyl) butane, 2,4,6-tris (3,5-di -Tert-butyl-4-hydroxybenzyl) isocyanurate and the like.

  Even if any of these hindered phenyl compounds is used, an effect that the development time can be shortened while maintaining a development margin is seen, but the effect is particularly effective when a polycyclic hindered phenyl compound is used. . By using a polycyclic hindered phenyl compound, the development margin can be further extended. Specific examples of the polycyclic hindered phenyl compound include 4,4′-thiobis (6-tert-butyl-3-methylphenol) and 4,4′-butylidenebis (6-tert-butyl-3-methylphenol). 4,4′-methylenebis (6-tert-butylphenol), 4,4′-bis (2,6-di-tert-butylphenol), 4,4′-thiobis (6-tert-butyl-o-cresol) 2,2′-methylenebis (4-methyl-6-tert-methylphenol), 2,2′-thiobis (6-butyl-4-methylphenol), 1,6-bis (3,5-tert-butyl) -4-hydroxy-2-methylphenyl) butane, 1,1,3-tris (5-tert-butyl-4-hydroxy-2-methylphenyl) butane, 2,4, - tris (3,5-di -tert- butyl-4-hydroxybenzyl) isocyanurate.

  One kind of hindered phenyl compound that can be used in the present invention may be used alone, or a mixture of two or more kinds may be used. In addition, it is preferable that the compounding ratio of a hindered phenyl compound is included in the range of 0.2-5 mass% in a positive photosensitive paste. More preferably, it exists in the range of 0.5-3 mass%. The development time can be shortened by including 0.2% by mass or more of the hindered phenyl compound, and the development margin can be maintained by setting it to 5% by mass or less.

  The inorganic powder in the present invention is appropriately selected depending on the intended paste. For example, as a paste for forming an insulating layer of an electronic component, a partition wall layer of a display, or the like, glass powder, ceramic powder, or a mixture of glass powder and ceramic powder can be used. The glass powder has a softening temperature of 900 ° C. or lower, preferably 350 to 800 ° C. Glass having a softening temperature of less than 350 ° C. has low chemical stability, and if the softening temperature exceeds 900 ° C., it becomes difficult to perform sufficient softening on the substrate. Any glass powder having a softening temperature of 800 ° C. or lower, preferably 350 to 800 ° C. can be used without any particular limitation, but glass containing alkali metal in a positive photosensitive paste using glass as a substrate. When powder is used, the substrate may be warped by an ion exchange reaction with the substrate glass during firing, so the alkali metal content is preferably 10% by mass or less. Ceramic powders that do not soften at a firing temperature of about 500 to 1000 ° C. can be widely used, and ceramic powders such as alumina, magnesia, calcia, cordierite, silica, mullite, zircon, and zirconia can be exemplified. In addition, an inorganic pigment may be included for identifying the insulating layer when multilayering. In the case of black, it is made of a compound such as Co—Cr—Fe, Co—Mn—Fe, Co—Cu—Mn, Co—Ni—Mn, Co—Ni—Cr—Mn, and Co—Ni—Cu—Mn. Black pigment, in the case of blue, Co-Al, Co-Al-Cr, Co-Al-Si, Zr-Si-V, Co-Zn-Si, Co-Zn-Al, Co-Zr-V, Co- For Si, green, Ca-Si-Cr, Sn-Zr-V, Zr-Si-Pr-V, Zr-Si-Pr-Cr-Fe, Cr-Al, Zr-Si-Pr-Cr, Cr In the case of -Co-Al-Zn, Cr-Al-Si, and vermilion, pigments such as Al-Mn, Al-Cr-Zn, Sn-Cr, and Zr-Si-Fe can be used. The amount of pigment added is usually in the range of 0.1 to 40% by mass, although it depends on the type of pigment.

  The paste for forming the conductive layer of the electronic component or display may be anything as long as it is an inorganic powder exhibiting conductivity, and may be a metal oxide or a carbon-based material, but preferably a metal powder can be used. As the metal powder, one selected from the group consisting of Ag, Au, Pd, Ni, Cu, Al, and Pt can be used. These may be in a single state or an alloy state.

  In the present invention, frit glass may be used as a component to be bonded to the substrate during firing, or for the purpose of enabling sintering at a low temperature, but the addition amount is 10 mass in the photosensitive conductive paste. % Or less is preferable. When the addition amount of frit glass exceeds 10% by mass, the specific resistance of the conductive pattern formed by the photosensitive conductive paste may increase.

  Although it does not specifically limit as frit glass, It is preferable that the glass transition temperature (Tg) and softening point (Ts) of frit glass are 400-800 degreeC and 450-850 degreeC, respectively. When Tg and Ts are less than 400 ° C. and 450 ° C., respectively, sintering of the glass starts before the organic components such as the binder resin evaporate, debinding is not successful, residual carbon is obtained after firing, and the conductive pattern is peeled off. This is not preferable in order to obtain a dense and low resistance conductive pattern. When the glass frit with Tg and Ts exceeding 800 ° C. and 850 ° C., respectively, when it is baked at a temperature of 900 ° C. or less, it is difficult to obtain a sufficient adhesive strength between the conductive pattern and the substrate or a dense electrode film.

  The particle diameter of these inorganic powders is selected in consideration of the thickness and line width of the layer to be produced. The center diameter of the volume-based distribution is 0.05 to 5 μm, and the maximum particle size is 15 μm or less. preferable.

  In the positive photosensitive paste of the present invention, an organic solvent, a dispersant, a thixotropic agent, a plasticizer, an ultraviolet absorber, a crosslinking agent, and the like can be appropriately used as additive components depending on the purpose.

  As the crosslinking agent, those containing one or more ethylenically unsaturated double bonds are preferably used. By adding a cross-linking agent, the cross-linking reaction between the cross-linking agent in the unexposed portion and the resin proceeds by post-baking after exposure, and the developer resistance can be improved.

  The positive photosensitive paste of the present invention is prepared by preparing an organic solution by preparing various components such as an organic component and other additives and a solvent as required to have a predetermined composition, and then adding an inorganic powder, It can be produced by mixing and dispersing homogeneously with a three-roller or a kneader.

  The viscosity of the photosensitive paste is adjusted to about 10,000 to 200,000 mPas with an organic solvent. As the organic solvent used at this time, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether, methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl ethyl ketone, dioxane, acetone, cyclohexanone, cyclopentanone, Examples thereof include isobutyl alcohol, isopropyl alcohol, tetrahydrofuran, dimethyl sulfoxide, γ-butyrolactone, and organic solvent mixtures containing one or more of these.

  The positive photosensitive paste thus obtained can be patterned as follows.

  First, a positive photosensitive paste is applied to the entire surface or a part of a glass or alumina substrate. As a coating method, methods such as a screen printing method, a bar coater, a roll coater, a die coater, and a blade coater can be used. The coating thickness can be adjusted by selecting the number of coatings, screen mesh and paste viscosity.

  Here, when applying the paste on the substrate, the substrate can be subjected to a surface treatment in order to improve the adhesion between the substrate and the coating film. Examples of the surface treatment liquid include silane coupling agents such as vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, tris (2-methoxyethoxy) vinylsilane, γ-glycidoxypropyltrimethoxysilane, γ- (methacrylic). Roxypropyl) trimethoxysilane, γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, or organic metals such as Organic titanium, organic aluminum, organic zirconium and the like. A silane coupling agent or an organic metal diluted with an organic solvent such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl alcohol, ethyl alcohol, propyl alcohol, or butyl alcohol to a concentration of 0.1 to 5% by mass Is used. Next, the surface treatment liquid can be applied to the substrate uniformly with a spinner or the like, and then dried at 80 to 140 ° C. for 10 to 60 minutes to carry out the surface treatment.

  After applying the positive photosensitive paste, drying is performed. Drying is performed at 60 to 150 ° C. for about 30 seconds to 60 minutes using a hot air dryer, IR dryer, hot plate or the like.

  After drying, exposure is performed using an exposure apparatus. A proximity exposure machine or the like can be used as the exposure apparatus. In addition, when performing exposure of a large area, a large area can be exposed with an exposure machine having a small exposure area by applying a positive photosensitive paste on a substrate and then performing exposure while being conveyed.

  After exposure, post-bake is performed as necessary. The post-baking is performed at 60 to 150 ° C. for about 30 seconds to 60 minutes using a hot air dryer, IR dryer, hot plate or the like.

  After exposure or post-baking, development is performed using the difference in solubility between the exposed portion and the non-exposed portion in an alkaline developer. In this case, the immersion method, spray method, and brush method are used. The developer is preferably composed mainly of water. As the alkaline aqueous solution, sodium hydroxide, sodium carbonate, calcium hydroxide aqueous solution or the like can be used. However, it is preferable to use an organic alkaline aqueous solution because an alkaline component can be easily removed during firing.

  As the organic alkali, a general amine compound can be used. Specific examples include tetramethylammonium hydroxide, trimethylbenzylammonium hydroxide, monoethanolamine, and diethanolamine.

  The density | concentration of aqueous alkali solution is 0.05-10 mass% normally, More preferably, it is 0.1-3 mass%. If the alkali concentration is too low, the soluble portion is not removed, and if the alkali concentration is too high, the pattern portion may be peeled off and the insoluble portion may be corroded. The development temperature during development is preferably 20 to 50 ° C. in terms of process control.

  Next, firing is performed in a firing furnace. The firing atmosphere and temperature vary depending on the type of paste and substrate, but firing is performed in an atmosphere of air, nitrogen, hydrogen, or the like. As the firing furnace, a batch-type firing furnace or a belt-type continuous firing furnace can be used.

  The firing temperature is 400 to 1000 ° C. In the case of an alumina substrate or the like, firing is possible at 800 to 1000 ° C., but when a glass substrate is used, firing is performed at a temperature of 520 to 620 ° C. for 10 to 60 minutes.

Hereinafter, the present invention will be specifically described by way of examples. However, the present invention is not limited to this.

  Polystyrene obtained by mixing novolac resin: m-cresol / p-cresol / formaldehyde at a molar ratio of 60/40/80, reacting in the presence of an oxalic acid catalyst under reflux, and then fractionating. A novolak resin having a converted weight average molecular weight of about 8000, and in a gel permeation chromatographic analysis (GPC) pattern, an area ratio of a polystyrene converted molecular weight of 6000 or less to the total pattern area excluding the pattern area of unreacted cresol is 34%, And the area ratio of polystyrene conversion molecular weight 1000 or less is 15%.

Acrylic resin: polyhydroxystyrene (Aldrich, weight average molecular weight 20,000)
Photoacid generator: ester of tetrahydroxybenzophenone and 2-diazo-1-naphthoquinone-5-sulfonic acid Conductive powder: average particle size 1.2 μm, specific surface area 1.12 m ² / g produced by wet reduction method, Silver powder having a tap density of 4.8 g / cm ³ .

  Organic solvent: diethylene glycol monobutyl ether acetate.

Dissolution accelerator A: 2,2′-methylenebis (4-methyl-6-tert-butylphenol)
Dissolution promoter B: 4,4'-methylenebis (2,6-di-tert-butylphenol)
Dissolution accelerator C: 4,4′-thiobis (3-methyl-6-tert-butylphenol)
Dissolution promoter D: 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzoyl) benzene Dissolution promoter E: Tris- (2-methyl-4 -Hydroxy-5-tert-butyl-phenol) butane dissolution accelerator F: 2,6-di-tert-butyl-4-methylphenol dissolution accelerator G: n-octadecyl-3- (3,5-di-tert -Butyl-4-hydroxyphenyl) propionate Dissolution accelerator H: Trihydroxybenzophenone Dissolution accelerator I: Methyl gallate (Preparation of positive photosensitive paste)
3 with 78% by weight of conductive powder, 9% by weight of novolak resin, 1% by weight of acrylic resin, 2% by weight of photoacid generator, 9% by weight of organic solvent, and 1% by weight of dissolution accelerator shown in Table 1 It was prepared by kneading with this roller.
(Development margin measurement)
The whole surface of the positive photosensitive paste was applied to a substrate (99.6% alumina substrate, 60 mm square, thickness 0.635 mm) using a Microtec screen printer and a 200 mesh screen plate, and dried with hot air from Tabai. It was dried at 100 ° C. for 20 minutes using a machine. The film thickness after drying was 25 μm. After drying, exposure was performed through a photomask having a stripe pattern with line and space (L / S) values of 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, and 60 μm, respectively. . As the exposure machine, a Dainippon Screen exposure machine (light source: 2 kW super high pressure mercury lamp) was used. After the exposure, shower development was performed using a 2.34% by mass tetramethylammonium hydroxide aqueous solution. Development was completed at intervals of 5 seconds, and resolution was observed using an optical microscope. The results are shown in Table 1. In Table 1, XX indicates a state in which a residual film is seen between patterns, ◯ indicates a state in which a pattern of 15 to 20 μm is obtained, and × indicates a state in which the pattern is peeled and a pattern of 15 to 20 μm is not obtained. It showed in.
(Examples 1-7, Comparative Examples 1-3)
The development time of Comparative Example 1 in which no dissolution accelerator was used was 100 seconds, while Examples 1 to 7 using a hindered phenol compound had good development times of 15 to 20 μm in 35 to 40 seconds. Pattern was obtained. Furthermore, a good pattern was obtained even if the development time was extended. In particular, in Examples 1 to 5 using a polycyclic hindered phenol compound, a better development margin was obtained.

  On the other hand, in Comparative Examples 2 and 3 using trihydroxybenzophenone and methyl gallate as the dissolution accelerator, the development time was shortened but there was almost no development margin.

Claims (4)

  A positive photosensitive paste containing an organic component and an inorganic powder, wherein the organic photosensitive component contains at least an alkali-soluble resin, a photoacid generator, and a hindered phenol compound as organic components.   A positive photosensitive paste containing an organic component and an inorganic powder, in which an alkali-soluble group is protected with an acid-eliminating group and a photoacid generator, or an alkali-soluble group is eliminated with an alkali. A positive photosensitive paste comprising a group-protected resin and a photobase generator, and further comprising a hindered phenol compound.   The positive photosensitive paste according to claim 1, comprising a polycyclic hindered phenol compound.   The positive photosensitive paste according to claim 1, wherein the inorganic powder is a metal powder selected from the group consisting of Ag, Au, Pd, Ni, Cu, Al, and Pt.