JPH06110209A - Positive type photosensitive anion electrodeposition coating resin composition, electrodeposition coating bath formed by using the composition, electrodeposition method and production of printed circuit board - Google Patents

Abstract

PURPOSE:To provide the positive type photosensitive anion electrodeposition coating material resin compsn. which has the good stability of the electrodeposition coating bath and electrodeposition coatability and yields an electrodeposition coating film having a high sensitivity and high resolution. CONSTITUTION:This positive type photosensitive anion electrodeposition coating material resin compsn contains (a) a polymer formed by neutralizing a polymer of 200 to 300 acid value copolymerized from an acrylic acid and/or methacrylic acid with a basic org. compd., (b) a compd. having a group unstable to an acid and (c) a compd. which generates an acid when irradiated with active rays. The above-mentioned electrodeposition coating bath, electrodeposition coating method and process for production of a printed circuit board use such a compsn.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positive photosensitive anion electrodeposition coating resin composition, an electrodeposition coating bath using the same, an electrodeposition coating method and a method for producing a printed wiring board.

[0002]

2. Description of the Related Art Conventionally, as a method of forming a resist pattern on the surface of a substrate, a method of forming a photosensitive layer on the surface of the substrate, then irradiating with an actinic ray and then developing is often used. Various methods are adopted for forming the photosensitive layer in this step. For example, dip coat, roll coat,
A method using a photosensitive resin composition solution (coating solution) such as curtain coating, or a method in which a photosensitive layer is formed in advance on a substrate film (hereinafter abbreviated as photosensitive film) is laminated on the substrate surface by using a laminator or the like. It is known how to do it. Among these methods, the method using a photosensitive film can easily form a photosensitive layer having a uniform thickness, and therefore is currently used as a mainstream method particularly in the field of printed wiring board manufacturing.

[0003]

Recently, as the density and precision of printed wiring boards have been increased, higher quality resist patterns have been required. That is, it is desired that the resist pattern has no pinhole and is well adhered to the surface of the underlying substrate. It is known that there is a limit to the method of laminating photosensitive films which is the mainstream at present in response to such a demand. In this method, the ability to follow unevenness on the substrate surface, which is caused by dents during manufacturing of the substrate, unevenness of polishing, meshes of the glass cloth of the inner layer of the substrate, unevenness of copper plating pits on the surface, etc., is poor. However, it is difficult to obtain sufficient adhesion. This difficulty is caused by laminating photosensitive films under reduced pressure (Japanese Patent Publication No. 59-3740).
This can be avoided to some extent by the method disclosed in Japanese Patent Laid-Open Publication No. 2003-242242, but this requires a special and expensive device.

For these reasons, the solution coating methods such as dip coating, roll coating and curtain coating have come to be reviewed again in recent years. However, these coating methods have problems that the film thickness is difficult to control, the film thickness is not uniform, and pinholes are generated.

Therefore, as a new method, a method of forming a photosensitive film by electrodeposition coating has been recently proposed (Japanese Patent Laid-Open No. 62-62160).
-235496 gazette). According to this method, the adhesion of the resist is improved, the conformability to irregularities on the substrate surface is good, and a photosensitive film having a uniform film thickness can be formed in a short time.
Since the coating liquid is an aqueous solution, it has the advantages that it can prevent contamination of the work environment and that there are no problems in disaster prevention.

Therefore, some proposals have been made in the past for positive-type photosensitive electrodeposition coatings which are considered to be particularly effective in the production of printed wiring boards having through holes.
Most of them use a quinonediazide group as a photosensitive group, but they have problems such as low photosensitivity and poor water dispersion stability and hydrolysis resistance of the photosensitive material.

On the other hand, in recent years, as a pattern forming method for manufacturing electronic parts such as semiconductor elements, magnetic bubble memories, integrated circuits, etc., a compound which generates an acid upon irradiation with actinic rays and a compound which is decomposed by the generated acid A large number of chemically amplified positive-working light-sensitive materials in which a compound having a property of increasing solubility in a developer is combined have been reported. According to these methods, a significantly higher sensitivity can be expected as compared with the conventional method using a quinonediazide group. However, at present, there is no example in which those material systems are made into electrodeposition paints and put into practical use.

Conventionally reported chemically amplified positive-working light-sensitive materials are usually dissolved in an organic solvent to form a coating film (photosensitive film) by a coating method. Even if water can be dispersed by the method, it cannot be easily used as an electrodeposition coating resin composition. Dispersion of the composition in water, stability in water after dispersion (water dispersion stability and hydrolysis resistance), electrodeposition coatability, and exposure of the film after electrodeposition coating It is necessary to consider all the characteristics and the like, and it is necessary to fundamentally modify the conventional chemically amplified positive-working photosensitive material. In consideration of all of these points, the present invention shows good photosensitivity characteristics such as high sensitivity and high resolution, and furthermore, stability of electrodeposition coating bath (water dispersion stability and hydrolysis resistance of light-sensitive material) and electrodeposition. The aim is to develop a positive-type photosensitive electrodeposition coating composition with good coatability.

[0009]

The present invention provides (a) an acid value of 20 to 3 obtained by copolymerizing (a) acrylic acid and / or methacrylic acid.
Positive polymer containing the polymer No. 00 neutralized with a basic organic compound, (b) a compound having an acid labile group, and (c) a compound capable of generating an acid upon irradiation with actinic rays. The present invention relates to a photosensitive anionic electrodeposition coating resin composition and an electrodeposition coating bath using the same. The present invention also relates to an electrodeposition coating method in which a substrate having a conductive surface is immersed in the electrodeposition coating bath, and a DC voltage is applied using this as an anode, and the electrodeposition coating obtained by the method. The present invention relates to a method for manufacturing a printed wiring board, which comprises exposing and developing a film.

The present invention takes advantage of the high sensitivity of the chemically amplified positive-working light-sensitive material, and fundamentally revises it to improve the water-dispersibility, water-dispersion stability and hydrolysis resistance of the light-sensitive material. Has been significantly improved, and in consideration of the electrodeposition coating property, it has been developed into a positive type photosensitive electrodeposition coating having high Coulomb efficiency. As a result, the problems of the low sensitivity of the positive-type photosensitive electrodeposition coating composition containing a conventional naphthoquinonediazide-based photosensitive material as a main component and the poor water dispersion stability and hydrolysis resistance of the photosensitive material are significantly improved. In addition, a positive-type photosensitive anion-electrolyte using a polymer obtained by copolymerizing a polymerizable monomer having an acid-labile group and a polymerizable monomer having a carboxylic acid such as acrylic acid and / or methacrylic acid together is used. Compared with the coating resin composition, a polymer having a carboxylic acid as a component (a component for imparting electrodeposition coating property) and a compound having a group unstable to an acid as a component for (b) (providing positive photosensitivity) The positive type photosensitive anion electrodeposition coating resin composition of the present invention in which the components) are separately used, the detailed reason is unknown, but the water dispersion stability of the electrodeposition bath is further improved, and the electrodeposition coating is also performed. The high sensitivity of the electrodeposition coating film (resist film) obtained later is further improved. The former copolymerizes a polymerizable monomer having a carboxylic acid and a polymerizable monomer having an acid-labile group, so that the polymer itself is harder than the latter, and the latter functions as a material. Due to the separation, it is considered that the presence of the polymer of the component for imparting electrodeposition coatability in the form of encapsulating the compound of the positive-type photosensitivity imparting the greater effect of the resin composition of the present invention. To be

The contents of the present invention will be described in detail below. The polymer as the component (a) has an acid value of 20 to 30 obtained by copolymerizing acrylic acid and / or methacrylic acid as an essential component.
It is a polymer obtained by neutralizing the polymer of No. 0 with a basic organic compound. Acrylic acid and methacrylic acid can be used alone or in combination, and the amount used is
The acid value of the polymer is appropriately used so as to fall within the range of 20 to 300. When the acid value of the polymer is less than 20, the water dispersion stability is poor when a basic organic compound is added to the photosensitive electrodeposition coating resin composition and then water is added to disperse the composition, and the composition easily precipitates. When the acid value of the polymer exceeds 300, the appearance of the electrodeposition film tends to be poor.

The polymer before neutralization includes, for example, methyl acrylate, other than acrylic acid and / or methacrylic acid.
Methyl methacrylate, ethyl methacrylate, butyl methacrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, n-hexyl acrylate, n-octyl acrylate, n-octyl methacrylate, n-decyl methacrylate, cyclohexyl methacrylate, 2-
It can be obtained by copolymerizing one or more kinds of polymerizable monomers such as ethylhexyl acrylate, cyclohexyl methacrylate, acrylonitrile, styrene and vinyl chloride. Among them, copolymerization of ethyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, etc., whose homopolymer has a glass transition temperature of 0 ° C. or lower, improves the water dispersion stability of the electrodeposition coating bath and the electrodeposition coating property. ,desirable.

Synthesis of the polymer before neutralization is carried out by a general solution polymerization of the above-mentioned polymerizable monomer in an organic solvent using a polymerization initiator such as azobisisobutyronitrile, azobisdimethylvaleronitrile, benzoyl peroxide and the like. Can be obtained by In this case, the organic solvent used is a hydrophilic organic solvent such as dioxane, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, propylene glycol monopropyl ether, ethylene glycol monoacetate, diethylene glycol monoethyl ether acetate, etc. It is preferable to mainly use the solvent. If toluene, xylene,
When a hydrophobic organic solvent such as benzene is mainly used,
After synthesizing the polymer, the solvent needs to be distilled off and replaced with the hydrophilic solvent. The weight average molecular weight of the polymer before neutralization (converted to standard polystyrene) is 20,000 to 150,
It is preferably in the range of 000. If it is less than 20,000, the water dispersion stability of the electrodeposition coating bath tends to be low, and the mechanical strength of the resist tends to be weak.
If it exceeds, the electrodeposition coatability tends to be poor and the appearance of the coating film tends to be poor.

The amount of the polymer used as the component (a) is preferably 40 to 85 parts by weight, preferably 55 to 75 parts by weight, based on 100 parts by weight of the total amount of the components (a) and (b). More preferably. If the amount used is less than 40 parts by weight, it is difficult to disperse water in the electrodeposition coating bath, and the mechanical strength of the resist tends to be weak, resulting in poor toughness.
If it exceeds 5 parts by weight, the proportion of the compound having an unstable group to the acid which is the component (b) tends to decrease and the sensitivity to light tends to decrease.

In obtaining the polymer as the component (a),
The method of neutralizing with a basic organic compound is not particularly limited, and a basic organic compound may be added to the polymer solution before neutralization for neutralization, and (b) and (c) will be described later. You may add a basic organic compound to the solution which mixed the component) with the polymer before neutralization, and neutralize it. In any case, by neutralizing the carboxyl group in the polymer before neutralization with a basic organic compound, a polymer that facilitates water-solubilization or water-dispersion is used as the polymer of the component (a), and the polymer is charged. The coating bath can be adjusted.

The basic organic compound used here is not particularly limited, and examples thereof include triethylamine, diethylamine, diethylmonoethanolamine, dimethylmonoethanolamine, diethanolamine, triethanolamine, diisopropylamine, and the like. They can be used alone or in combination of two or more.

The amount of these basic organic compounds used is 0. 1 with respect to 1 equivalent of carboxyl groups in the polymer before neutralization.
It is preferably in the range of 2 to 1.0 equivalent. If it is less than 0.2 equivalent, the water dispersion stability of the electrodeposition coating bath tends to decrease, and if it exceeds 1.0 equivalent, the thickness of the coating film after electrodeposition coating becomes thin and the appearance of the coating film tends to deteriorate. is there.

The compound having an acid labile group as the component (b) is not particularly limited as long as it has at least one acid labile group in one molecule. Various compounds can be used.

The acid labile group may be any group which is easily decomposed in the presence of an acid, for example, t-
Butyl ester group, t-amyl ester group, isobornyl ester group, tetrahydropyranyl ester group, t-
Examples thereof include a butyl carbonate group, a t-aluminum carbonate group, an isobornyl carbonate group, a trimethylsiloxy group, a tetrahydrofuranyl ester group, an acetal group, a ketal group, an orthoester group and an enol ether group. Of these acid-labile groups, a t-amyl ester group, a t-butyl ester group and a tetrahydropyranyl ester group are particularly preferable from the viewpoints of photosensitivity and stability of the electrodeposition coating bath.

As the component (b), when the compound having an acid labile group is a low molecular weight compound, for example, a compound represented by the following formula is used.

[0021]

[Chemical 3]

[0022]

[Chemical 4]

[0023]

[Chemical 5]

[0024]

[Chemical 6]

[0025]

[Chemical 7]

Further, as the component (b), a polymer obtained by homopolymerizing a polymerizable monomer having an acid labile group or copolymerizing it with another polymerizable monomer can be used.
Examples of the polymerizable monomer having an acid labile group include compounds having the following structural formulas. R in the structural formula represents, for example, a t-amyl group, a t-butyl group, a tetrahydropyranyl group, or the like.

[0027]

[Chemical 8]

Among them, considering the stability and photosensitivity of the electrodeposition coating bath, t-amyl acrylate, t-amyl methacrylate, t-butyl acrylate, t-butyl methacrylate, tetrahydropyranyl acrylate, tetrahydropyranyl methacrylate and the like are used. preferable.

Other polymerizable monomers to be copolymerized with the polymerizable monomer having an acid labile group include, for example, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, 2-ethylhexyl methacrylate and lauryl methacrylate. , Benzyl methacrylate, cyclohexyl methacrylate, ethyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, benzyl acrylate, cyclohexyl acrylate, acrylonitrile, styrene, α-methylstyrene, diacetone acrylamide, vinyltoluene and the like. However, the polymerizable monomer having a carboxylic acid such as acrylic acid or methacrylic acid is excluded from the other polymerizable monomers. Other polymerizable monomers can be copolymerized by using one or more kinds in combination. The copolymerization amount of these other polymerizable monomers is preferably 80 parts by weight or less based on 100 parts by weight of the total amount of all the monomers constituting the copolymer. If it exceeds 80 parts by weight, the photosensitivity tends to be low. When a polymerizable monomer having a carboxylic acid such as acrylic acid or methacrylic acid is copolymerized in the component (b), the component (b) is present separately from the polymer of the component (a) in the electrodeposition coating bath, Due to the difference in co-propulsion between the components (a) and (b) (difference in electrophoresis speed) during electrodeposition coating, the ratio of the components (a) and (b) in the obtained electrodeposition film changed. There is a possibility that it will happen, which is not preferable.

The method of homopolymerizing the polymerizable monomer having an acid labile group or the copolymerization with another polymerizable monomer is basically the same as the method of synthesizing the polymer of the component (a) described above. Is. However, the component (b) thus obtained by polymerization is preferably a low molecular weight polymer, and in that case, the weight average molecular weight is preferably in the range of 400 to 10,000, more preferably 800 to 4,000. . If the weight average molecular weight is less than 400, unreacted polymerizable monomers may remain, and the positive photosensitive properties tend to be impaired. Further, the weight average molecular weight is 10,0.
If it exceeds 00, the compatibility with the polymer as the component (a) and the water dispersibility of the electrodeposition coating bath tend to be lowered. Therefore, the method for synthesizing the polymer as the component (b) is different from the case of synthesizing the polymer as the component (a) in that, for example, the amount of the polymerization initiator is increased and the polymerization temperature is increased to obtain a low molecular weight polymer. And need to. Furthermore, the target low molecular weight polymer can be obtained by carrying out chain transfer polymerization using a chain transfer agent such as a halogen compound or a thiol derivative. It is preferable to use such a low molecular weight polymer as the component (b) from the viewpoints of the water dispersion stability of the electrodeposition coating bath, the electrodeposition coating property, the photosensitive property of the resist and the like. The compound having an acid labile group as the component (b) may be one type, or two or more types may be used in combination.

The amount of the compound having an acid labile group which is the component (b) is 15 to 60 parts by weight based on 100 parts by weight of the total amount of the components (a) and (b). Is preferable, and it is more preferable to set it in the range of 25 to 45 parts by weight. If the amount used is less than 15 parts by weight, the sensitivity of the resist to light tends to decrease, and if it exceeds 60 parts by weight, the water dispersibility of the electrodeposition coating bath decreases and the mechanical strength of the resist decreases. It is weak and tends to have poor toughness.

The compound (c) which generates an acid upon irradiation with actinic rays will be described. Examples of the compound that generates an acid upon irradiation with actinic rays include, for example,

[0033]

[Chemical 9] An oxadiazole derivative substituted with a trihalomethyl group such as

[0034]

[Chemical 10] An s-triazine derivative substituted with a trihalomethyl group such as

[0035]

[Chemical 11] Iodonium salts such as

[0036]

[Chemical 12] Sulfonium salts such as

[0037]

[Chemical 13] A disulfone derivative such as

[0038]

[Chemical 14] And imidosulfonate derivatives thereof.

Among these, the compound represented by the following general formula (I) or the compound represented by the general formula (II) is preferable because it has photosensitivity in a long wavelength region.

[Chemical 15] [In the formula, R ¹ represents an alkyl group]

[0040]

[Chemical 16] [Wherein R ¹ represents an alkyl group, R ² represents hydrogen, an alkyl group, an alkoxy group or an aryl group, X represents I or S, and n represents 2 or 3] Representative examples of these compounds Are listed below.

[0041]

[Chemical 17]

[0042]

[Chemical 18]

[0043]

[Chemical 19]

[0044]

[Chemical 20]

[0045]

[Chemical 21]

The compound (c) which forms an acid upon irradiation with these actinic rays is in the range of 0.1 to 30 parts by weight per 100 parts by weight of the total amount of the components (a), (b) and (c). It is preferably used, and more preferably in the range of 1 to 15 parts by weight. If the amount used is less than 0.1 parts by weight, the photosensitivity of the resist is too low, and if it exceeds 30 parts by weight, the thermal stability of the resist tends to decrease and the resolution of the resist pattern tends to decrease.

The positive photosensitive anion electrodeposition coating resin composition of the present invention may contain a compound which increases the acid generation efficiency of the compound which generates an acid upon irradiation with actinic rays. Examples of such a sensitizer include anthracene, phenanthrene, pyrene, thioxanthone,
Examples thereof include benzophenone, anthuron, Michler's ketone, 9-fluorenone, and phenothiazine. The amount of these sensitizers used and the compounding ratio of the compound that generates an acid upon irradiation with actinic rays are 0.01 / 1 in terms of molar ratio (sensitizer / compound that generates an acid upon irradiation with actinic rays).
˜20 / 1, preferably 0.1 / 1 to 5/1
Is more preferable, and 0.1 / 1 to 1/1 is particularly preferable.

Dyes, pigments, plasticizers, adhesion promoters, surface smoothing agents, dispersants, inorganic fillers and the like can be appropriately added to the positive photosensitive anion electrodeposition coating resin composition of the present invention. .

In order to make the positive photosensitive anion electrodeposition coating resin composition of the present invention described above into an electrodeposition coating composition, it is preferable to first dissolve the above-mentioned various components uniformly in a hydrophilic organic solvent. It is not necessary to stick to this. Examples of the hydrophilic organic solvent used herein include dioxane, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monopropyl ether, diethylene glycol and the like. These solvents may be used alone or in admixture of two or more, and the amount used is 3 with respect to 100 parts by weight of the total solid content.
A range of not more than 00 parts by weight is preferable.

Next, a basic organic compound is added to this solution to neutralize the carboxyl groups contained in the polymer as the component (a), thereby facilitating water-solubilization or water-dispersion of the composition. . Of course, the polymer of the component (a) may be neutralized with a basic organic compound in advance, as described above. The examples and the amounts of the basic organic compounds used are also as described above.

Next, water is added to dissolve or disperse the positive photosensitive anion electrodeposition coating resin composition in water to prepare an electrodeposition coating bath. The solid content of the electrodeposition coating bath is usually 5 to 20% by weight, and the pH is preferably 6.0 to 10.0.
If the pH is less than 6.0, the dispersion may be deteriorated and electrophoresis may become difficult. If the pH exceeds 10.0, the film once electrodeposited may be redissolved, and as a result, the film may not be formed. In order to adjust the pH to the above preferable range, the above-mentioned base may be added later to adjust the pH.

Further, in order to improve the water dispersibility and dispersion stability of the positive photosensitive anionic electrodeposition coating resin composition, a nonionic, cationic, anionic or other surfactant may be appropriately added. it can. Further, a hydrophobic solvent such as toluene, xylene, and 2-ethylhexyl alcohol can be appropriately added to increase the coating amount during electrodeposition coating.

Using the electrodeposition coating bath thus obtained, the substrate surface (in this case, at least the substrate surface is a metal such as iron, aluminum, copper, zinc, other metals and alloys, or another conductive material ( (For example, polypyrrole), which is required to exhibit conductivity), the substrate is immersed in an electrodeposition coating bath as an anode and, for example, a DC voltage of 40 to 400 V or 20 ~ 400mA
A direct current of / dm ² is applied for 10 seconds to 5 minutes. At this time, it is desirable to control the temperature of the electrodeposition coating bath to 15 to 30 ° C.

After the electrodeposition coating, the object to be coated is taken out from the electrodeposition coating bath, washed with water, drained and then dried with hot air or the like. At this time, if the drying temperature is high, an acid-labile group in the positive photosensitive anion electrodeposition coating resin composition may be decomposed. Therefore, it is usually preferable to dry at 110 ° C. or lower.

The thickness of the coating film (photosensitive layer) thus obtained is preferably 2 to 50 μm. Film thickness is 2 μm
If it is less than, the developing solution resistance is low, and, for example, when used in the production of a printed wiring board, there is a tendency that the etching solution resistance and the etch factor are inferior in the etching treatment after forming the resist pattern, Also, the film thickness is 50
If it exceeds μm, the resolution of the resist pattern may decrease.

Then, the coating film is imagewise irradiated with an actinic ray to generate an acid in the exposed area, and then 60 to 1 depending on the case.
After heating at 50 ° C. for 1 to 40 minutes, the exposed portion is removed by development to obtain a resist pattern. Examples of the light source of actinic rays include a mercury lamp, a xenon lamp, a metal halide lamp, a chemical lamp, a carbon arc lamp, a g-ray, an i-ray, a deep-UV ray, a helium neon laser, an argon ion laser, a krypton ion laser, and a helium. It is also possible to use a high-density energy beam such as a Cadmium ion laser or a KrF excimer laser.

The developer used for development is preferably an aqueous solution of an inorganic alkali such as sodium metasilicate, sodium carbonate, sodium hydroxide or potassium hydroxide or an organic alkali such as tetraalkylammonium salt. The concentration of these alkaline aqueous solutions is preferably 0.1 to 15% by weight, and more preferably 0.5 to 5% by weight. If it is less than 0.1% by weight, it is difficult to completely remove the exposed portion in a short time, and if it exceeds 15% by weight, the unexposed portion may be partially damaged. The developing method is performed by spraying the above developing solution or immersing it in the developing solution.

[0058]

EXAMPLES Next, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto. Example of Synthesis of Polymer as Component (a) Synthesis of Polymer (a-1) 1,130 g of dioxane was added to a flask equipped with a stirrer, a reflux condenser, a thermometer, a dropping funnel and a nitrogen gas introducing tube, and stirred. Nitrogen gas was blown in and heated to 90 ° C. When the temperature became constant at 90 ° C, 169 g of methacrylic acid, 250 g of methyl methacrylate, 381 g of n-butyl acrylate, 200 of ethyl methacrylate.
g and azobisisobutyronitrile 10 g were mixed and added dropwise into the flask over 2.5 hours, then 90 ° C.
It was kept warm for 3 hours with stirring. After 3 hours, a solution prepared by dissolving 3 g of azobisisobutyronitrile in 100 g of dioxane was dropped into the flask over 10 minutes, and then 90 ° C.
It was kept warm for 4 hours with stirring.

The polymer (a-
The weight average molecular weight of 1) was 55,000 and the acid value was 110. The solid content of the polymer solution was 45.1% by weight.

Synthesis of Polymer (a-2) Propylene glycol monomethyl ether 1,1 was placed in a flask equipped with the same equipment as in the synthesis of polymer (a-1).
Nitrogen gas is blown in while adding 30 g and stirring to 90 ° C.
Warmed to. When the temperature became constant at 90 ° C, 230 g of methacrylic acid, 367 g of methyl methacrylate,
250 g of ethyl acrylate, 153 g of 2-ethylhexyl acrylate and 10 of azobisisobutyronitrile
The liquid in which g was mixed was dropped into the flask over 2 hours.
Then, the mixture was kept at 90 ° C. for 3 hours while stirring. After 3 hours, 1 g of a solution prepared by mixing 5 g of azobisdimethylvaleronitrile with 100 g of propylene glycol monomethyl ether.
The mixture was dropped into the flask over 0 minutes, and then the mixture was kept at 90 ° C. for 4 hours while stirring.

The polymer (a-
The weight average molecular weight of 2) was 41,000 and the acid value was 158. The solid content of the polymer solution was 45.3% by weight.

Example of Synthesis of Low Molecular Weight Polymer as Component (b) Synthesis of Low Molecular Weight Polymer (b-1) Propylene glycol monomethyl ether 600 was placed in a flask equipped with the same device as in the synthesis of the polymer (a-1).
g was added and nitrogen gas was blown in with stirring to heat to 100 ° C. When the temperature became constant at 100 ° C, t
-A liquid obtained by mixing 400 g of amyl methacrylate and 60 g of azobisdimethylvaleronitrile was dropped into the flask over 2 hours. After that, the temperature was kept at 100 ° C. for 8 hours, and then the solvent was distilled off. The low molecular weight polymer (b-1) thus obtained had a weight average molecular weight of 2,600.

Synthesis of low molecular weight polymer (b-2) Propylene glycol monomethyl ether 800 was placed in a flask equipped with the same equipment as in the synthesis of polymer (a-1).
g and 200 g of 2-ethylhexyl thioglycolate which is a chain transfer agent were added, nitrogen gas was blown in while stirring, and the mixture was heated to 80 ° C. When the temperature became constant at 80 ° C, 400 g of tetrahydropyranyl methacrylate
A liquid obtained by mixing 55 g of azobisdimethylvaleronitrile and azobisdimethylvaleronitrile was dropped into the flask over 2 hours. Then 80 ° C
After keeping the temperature for 8 hours, the solvent and the chain transfer agent were distilled off. The low molecular weight polymer (b-2) thus obtained had a weight average molecular weight of 1,800.

Synthesis of low molecular weight polymer (b-3) Propylene glycol monomethyl ether 600 was placed in a flask equipped with the same equipment as in the synthesis of polymer (a-1).
g was added and nitrogen gas was blown in with stirring to heat to 100 ° C. When the temperature became constant at 100 ° C, t
A liquid obtained by mixing 300 g of butyl methacrylate, 100 g of 2-ethylhexyl acrylate and 40 g of azobisdimethylvaleronitrile was dropped into the flask over 2 hours. After that, the temperature was kept at 100 ° C. for 8 hours, and then the solvent was distilled off. Low molecular weight polymer (b-3) thus obtained
Had a weight average molecular weight of 4,500.

Synthesis of low molecular weight polymer (b-4) Propylene glycol monomethyl ether 600 was placed in a flask equipped with the same equipment as in the synthesis of polymer (a-1).
Nitrogen gas was blown in while adding g, and the mixture was heated to 90 ° C. When the temperature became constant at 90 ° C., 270 g of t-amyl acrylate, 5 n-butyl acrylate
A liquid obtained by mixing 0 g, 80 g of ethyl acrylate and 20 g of azobisdimethylvaleronitrile was dropped into the flask over 2 hours. After that, the temperature was kept at 90 ° C. for 8 hours, and then the solvent was distilled off. The weight average molecular weight of the low molecular weight polymer (b-4) thus obtained was 7,200.

Synthesis of low molecular weight polymer (b-5) Propylene glycol monomethyl ether 600 was placed in a flask equipped with the same equipment as in the synthesis of polymer (a-1).
g and 150 g of 2-ethylhexyl thioglycolate, which is a chain transfer agent, were added and nitrogen gas was blown in while stirring, and the mixture was heated to 115 ° C. When the temperature became constant at 115 ° C, 2 g of a mixture of 400 g of t-amyl methacrylate and 60 g of azobisdimethylvaleronitrile was mixed.
It dripped in the flask over time. 8 at 115 ° C
After keeping the temperature for a while, the solvent and the chain transfer agent were distilled off. The weight average molecular weight of the low molecular weight polymer (b-5) thus obtained was 900.

Example 1 Solution 443 g of polymer (a-1) (solid content 200 g)
150 g of the low molecular weight polymer (b-1), and 25 g of the exemplified compound (I-7) in the present text and 230 g of propylene glycol monomethyl ether were added and dissolved as the component (c). After further adding 32 g of triethylamine for neutralization, 2,900 g of distilled water was gradually added dropwise while stirring the liquid to obtain an electrodeposition coating bath (pH 8.1).

Example 2 443 g of solution of polymer (a-1) (solid content 200 g)
100 g of the low molecular weight polymer (b-3), 26 g of the exemplified compound (II-3) in the text and 180 g of propylene glycol monomethyl ether were added and dissolved as the component (c). After further adding 28 g of triethylamine for neutralization, 2,500 g of distilled water was gradually added dropwise while stirring the liquid to obtain an electrodeposition coating bath (pH 8.1).

Example 3 443 g of solution of polymer (a-1) (solid content 200 g)
140 g of the low molecular weight polymer (b-4), 32 g of the exemplified compound (II-6) in the text as a component (c), and a mixed solvent of 215 g of propylene glycol monomethyl ether and 43 g of propylene glycol monopropyl ether were added and dissolved. . Further, 36 g of diethylmonoethanolamine was added for neutralization, and then 2,850 g of distilled water was gradually added dropwise while stirring the liquid to obtain an electrodeposition coating bath (pH 8.2).

Example 4 443 g of a solution of the polymer (a-1) (solid content 200 g)
80 g of the low molecular weight polymer (b-5), 16 g of the exemplified compound (I-5) in the text as the component (c) and 150 g of propylene glycol monomethyl ether were added and dissolved. After further adding 28 g of triethylamine for neutralization, 2,300 g of distilled water was gradually added dropwise while stirring the liquid to obtain an electrodeposition coating bath (pH 8.1).

Example 5 442 g of a solution of polymer (a-2) (solid content 200 g)
200 g of the low molecular weight polymer (b-2), 20 g of the exemplified compound (II-12) in the text and 280 g of propylene glycol monomethyl ether were added and dissolved as the component (c). 25 g of dimethyl monoethanolamine
After neutralizing, the solution is stirred and distilled water 3,40
Gradually add 0 g dropwise to the electrodeposition coating bath (pH
7.8) was obtained.

Example 6 Solution 442 g of polymer (a-2) (solid content 200 g)
In addition, 200 g of di-t-amyl terephthalate, which is a low molecular weight compound of the component (b), and 17 g of the exemplified compound (I-7) in the text, 200 g of dioxane, and 50 g of a propylene glycol monomethyl ether are added as the component (c). Dissolved. After further neutralizing by adding 20 g of triethylamine, 2,900 g of distilled water while stirring the liquid
Is gradually added dropwise, and the electrodeposition coating bath (pH 7.
7) was obtained.

Example 7 442 g of a solution of the polymer (a-2) (solid content: 200 g)
In addition, 30 g of low molecular weight compound (b), di-tetrahydropyranyl terephthalate, and low molecular weight polymer (b-
3) 120 g, low molecular weight polymer (b-5) 60 g,
As the component (c), 25 g of the exemplified compound (I-7) in the text and 300 g of propylene glycol monomethyl ether were added and dissolved. After further adding 25 g of triethylamine for neutralization, 3,100 g of distilled water was gradually added dropwise while stirring the liquid, and an electrodeposition coating bath (pH 7.8) was added.
Got

Comparative Example 1 141 g of 2-ethylhexyl gallate and 402 g of 1,2-naphthoquinonediazide-5-sulfonic acid chloride
The solution of 4,000 g in dioxane was heated to 40 ° C. with stirring, and 160 g of triethylamine was added thereto.
Was added dropwise over 1 hour. After dropping, the mixture was reacted at 40 ° C. for 5 hours, and then the reaction product was poured into a 0.1 N hydrochloric acid aqueous solution, and the obtained precipitate was purified and filtered to obtain 2-ethylhexyl gallate and 1,2-naphthoquinonediazide. 435 g of an ester compound with -5-sulfonic acid was obtained.

The naphthoquinonediazide compound 6 was added to 443 g of the solution of the polymer (a-1) (solid content: 200 g).
0 g and 110 g of dioxane were added and dissolved. After further adding 28 g of triethylamine for neutralization, 2,000 g of distilled water was gradually added dropwise while stirring the liquid to obtain an electrodeposition coating bath (pH 8.0).

Comparative Example 2 Poly (p-vinylphenol), 12 (trade name, linker M, weight average molecular weight 1,600, manufactured by Maruzen Petrochemical)
A solution of 0 g and 170 g of 1,2-naphthoquinonediazide-5-sulfonic acid chloride in 3,000 g of dioxane was heated to 40 ° C. with stirring and heated to 40%.
650 g of a sodium carbonate aqueous solution of was added dropwise over 1 hour.
After the dropping, the mixture was further reacted with stirring at 40 ° C. for 3 hours, and then the reaction product was poured into a 0.1 N hydrochloric acid aqueous solution, and the obtained precipitate was purified and filtered to obtain poly (p-vinylphenol). Naphthoquinonediazide compound 2 in which 46.5 equivalent% of hydroxyl groups are substituted with naphthoquinonediazide groups
20 g was obtained.

The above-mentioned naphthoquinonediazide compound 8 was added to 442 g of a solution of polymer (a-2) (solid content: 200 g).
0 g and 120 g of dioxane were added and dissolved. After further adding 22 g of triethylamine for neutralization, 2,200 g of distilled water was gradually added dropwise while stirring the liquid to obtain an electrodeposition coating bath (pH 7.9).

Comparative Example 3 Propylene glycol monopropyl ether 11 was placed in a flask equipped with the same device as in the synthesis of polymer (a-1).
Add 30 g and blow with nitrogen gas while stirring to 100
Heated to a temperature of ° C. When the temperature became constant at 100 ° C., 3 parts of a liquid containing 54 g of methacrylic acid, 290 g of t-butyl methacrylate, 200 g of n-butyl acrylate, 256 g of methyl methacrylate, 200 g of ethyl acrylate and 10 g of azobisisobutyronitrile was mixed.
It was added dropwise to the flask over time. Then, the temperature was maintained at 100 ° C. for 3 hours while stirring. After 3 hours, a solution prepared by dissolving 3 g of azobisdemethylvaleronitrile in 100 g of propylene glycol monopropyl ether was added dropwise to the flask over 10 minutes, and then the temperature was again kept at 100 ° C. for 4 hours with stirring. The polymer thus obtained had a weight average molecular weight of 31,000 and an acid value of 36.1. The solid content of the polymer solution was 45.1% by weight.

To 666 g of the above polymer solution, 24 g of the exemplified compound (I-5) in the text and 200 g of dioxane were added and dissolved. After further adding 20 g of triethylamine for neutralization, 2300 g of distilled water was gradually added dropwise while stirring the liquid to obtain an electrodeposition coating bath (pH 8.9).

Glass epoxy copper clad laminates (Hitachi Chemical Co., Ltd.) were applied to each of the electrodeposition coating baths of Examples 1 to 7 and Comparative Examples 1 to 3 (the stability of each electrodeposition coating bath is shown in Table 1). ) MCL
-E-61) as an anode, stainless steel plate (SUS30
4, shape 200 mm × 75 mm × 1 mm) was immersed as a cathode, and a DC voltage was applied for 3 minutes at a temperature of 25 ° C. so that the thickness of the electrodeposition coating film (resist film) was 8 μm. An electrodeposition coating film was formed on the surface of (the respective applied voltages are shown in Table 1). After that, wash with water and drain at 15 ° C for 15 minutes.
Min dried.

A step tablet (a photomask having an optical density of 0.05 is used as the first step and a photomask in which each step is increased by 0.15 is used) is used for 6 steps with a 3 kW ultra-high pressure mercury lamp through a photomask. In the case of Examples 1 to 7 and Comparative Example 3, the amount of light for obtaining was further exposed to 1 ° C. at 130 ° C.
It was heated for 0 minutes (each exposure amount is shown in Table 1).

After cooling the substrate, spray development with a 1% by weight aqueous solution of sodium carbonate (spray pressure 1.0 kg / cm
² ) I did. The resist pattern resolution at this time is shown in Table 1.
Shown in.

[0083]

[Table 1]

Note 1) Evaluating the number of days until a precipitate is generated after standing the electrodeposition coating bath at 25 ° C. Note 2) After standing the electrodeposition coating bath at 25 ° C. Reversed-phase liquid chromatography and gel permeation chromatography analysis were performed on the coating bath, and in the case of Examples 1 to 7,
Regarding components (b) and (c), the presence or absence of hydrolysis was examined for the naphthoquinonediazide compound in Comparative Examples 1 and 2, and for the polymer in Comparative Example 3. From the results of each chromatographic analysis, the number of days until it was confirmed that hydrolysis had begun to occur was evaluated. Note 3) The voltage applied during electrodeposition coating, the exposure dose of the resist, and the resolution are all the data obtained when an electrodeposition coating film was obtained by electrodeposition coating immediately after the bath. In the case of Examples 1 to 7, no change was observed in each data even when the aged electrodeposition coating bath was used, but Comparative Examples 1 to 2
In this case, the electrodeposition coatability and the photosensitivity of the resist changed with the passage of time, and particularly when the naphthoquinonediazide compound started to hydrolyze, the respective properties remarkably deteriorated.

As is clear from Table 1, the stability of the electrodeposition coating baths according to the present invention shown in Examples 1 to 7 is extremely good, and since a predetermined film thickness can be formed at a low voltage, it is possible to obtain an electric charge. Good coatability. The photosensitivity of the obtained resist was also high, and a high-resolution resist pattern could be formed. However, in the conventional positive-type photosensitive electrodeposition coating compositions containing the naphthoquinonediazide type photosensitive materials shown in Comparative Examples 1 and 2, all of the stability of the electrodeposition coating bath, the electrodeposition coating property and the photosensitive characteristics are It can be seen that the invention is inferior to those of Examples 1 to 7. On the other hand, Comparative Example 3 shows the case where one polymer has a carboxylic acid and an acid-labile group, here, a t-butyl ester group. In general, it has better characteristics than Comparative Examples 1 and 2, but is inferior to Examples 1 to 7 according to the present invention in terms of water dispersion stability and photosensitivity of the electrodeposition coating bath. I understand.

The copper clad laminates having the high-resolution resist patterns formed on their surfaces obtained in Examples 1 to 7 were etched with an aqueous solution of cupric chloride, and the resist was stripped with an aqueous solution of 5% by weight of sodium hydroxide. As a result, a high-density printed wiring board could be obtained.

[0087]

The stability of the electrodeposition coating bath using the positive photosensitive anion electrodeposition coating resin composition of the present invention is extremely high. The electrodeposition coating bath has a good electrodeposition coating property, and the obtained electrodeposition coating film has extremely excellent photosensitivity, so that a high-resolution resist pattern can be formed. Such a resist pattern can be used as a relief, and an extremely high-precision and high-density printed wiring board can be manufactured by forming a resist pattern by etching or plating using a copper clad laminate as a substrate. You can

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display location G03F 7/004 503 7/033 H05K 3/06 6921-4E (72) Inventor Shigeo Tachiki Hitachi, Ibaraki Prefecture 13-1, Higashi-cho, Yokohama-shi Ibaraki Research Center, Hitachi Chemical Co., Ltd.

Claims (7)

[Claims] 1. A polymer obtained by neutralizing (a) a polymer having an acid value of 20 to 300 obtained by copolymerizing acrylic acid and / or methacrylic acid with a basic organic compound, and (b) an acid-labile group. A positive photosensitive anion electrodeposition coating resin composition comprising the compound having the above and (c) a compound capable of generating an acid upon irradiation with actinic rays. 2. The acid-labile group in the component (b) is at least one group selected from the group consisting of t-amyl ester group, t-butyl ester group and tetrahydropyranyl ester group. Item 3. The positive photosensitive anion electrodeposition coating resin composition according to Item 1. 3. The weight of the component (b) having an acid labile group, which is obtained by homopolymerizing or copolymerizing a polymerizable monomer having an acid labile group with another polymerizable monomer. The positive photosensitive anion electrodeposition coating resin composition according to claim 1 or 2, which is a low molecular weight polymer having an average molecular weight of 400 to 10,000. 4. A compound represented by the following general formula (I) and / or a general formula (II) wherein the component (c) which generates an acid upon irradiation with actinic rays is represented by the following general formula (II). Positive type photosensitive anion electrodeposition coating resin composition. [Chemical 1] (In the formula, R ¹ represents an alkyl group) (In the formula, R ¹ represents an alkyl group, R ² represents hydrogen, an alkyl group, an alkoxy group or an aryl group, X represents I or S, and n represents 2 or 3.) 5. An electrodeposition coating bath containing the positive photosensitive anion electrodeposition coating resin composition according to claim 1, 2, 3 or 4. 6. An electrodeposition coating method, which comprises immersing a substrate having a conductive surface in the electrodeposition coating bath according to claim 5, and applying a DC voltage using the substrate as an anode. 7. A method for manufacturing a printed wiring board, which comprises exposing and developing an electrodeposition coating film electrodeposited on the substrate by the method according to claim 6.