JPH06287486A - Negative photosetting electrodeposition coating compound resin composition, electrodeposition coating bath, production of resist pattern, electrically-conductive substrate with produced resist pattern, production of printed circuit board, printed circuit board and device - Google Patents

Abstract

PURPOSE:To obtain the subject composition having excellent flexibility of film, attaining high resolution, comprising a polymer prepared by neutralizing a (meth)acrylic acid copolymer with a basic organic compound, a specific photopolymerizable unsaturated compound and a water-insoluble photoinitiator. CONSTITUTION:The objective polymer comprises (A) a polymer prepared by neutralizing a polymer prepared by copolymerizing acrylic acid and/or methacrylic acid, having 20-300 acid value, with a basic organic compound, (B) a photopolymerizable unsaturated compound of the formula (R1 and R2 are H or methyl; k, m and n are >=0, k+m is >=1 and k+m+n is 2-15) and (C) a water-insoluble photoinitiator (e.g. benzophenone). The compound of the formula, for example, is obtained by introducing ethylene oxide into water, reacting in the presence of an alkali catalyst and dehydrating a formed dialcohol with (meth)acrylic acid.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a resin composition for a negative photosensitive electrodeposition coating, an electrodeposition coating bath, a method for producing a resist pattern, a conductive substrate having a resist pattern produced thereon, and a method for producing a printed circuit board. , Printed circuit boards and equipment.

[0002]

2. Description of the Related Art When manufacturing a printed circuit board,
First, a layer of a photocurable resin composition is formed on a substrate, and then an actinic ray is imagewise irradiated to develop and remove an unexposed portion to form a resist pattern. In this step, various methods are adopted for forming the layer of the photocurable resin composition. For example, a method using a photocurable resin composition solution (coating liquid) such as dip coating, roll coating, or curtain coating, or a method of laminating a film (photosensitive film) of the photocurable resin composition is known. . Among these methods, the method of laminating a photosensitive film is currently used as a mainstream method because it can easily form a layer of a photocurable resin composition having a uniform thickness.

[0003]

Recently, as the density and precision of printed circuit boards have increased, higher quality resist patterns have become necessary. 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 the photosensitive film, which is the mainstream at present, with respect 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 the films under reduced pressure (Japanese Patent Publication No. 59-3).
However, this requires special and expensive equipment.

For these reasons, 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 it is difficult to control the film thickness, the film thickness is not uniform, and pinholes occur.

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 (1)
The adhesion of the resist is improved, (2) the conformability to irregularities on the substrate surface is good, (3) a photosensitive film having a uniform film thickness can be formed in a short time, (4) the coating liquid is an aqueous solution The advantages are that it can prevent the pollution of the work environment and there is no problem in disaster prevention. Therefore, some proposals have recently been made regarding the composition of the electrodeposition bath suitable for this.

The electrodeposition coating method is mainly advantageous for an outer layer substrate having a through hole because a resist can be formed also in the through hole, or for a flexible substrate or the like because of good followability. Among them, the pattern width is becoming finer year by year, and it is becoming extremely difficult to maintain the manufacturing yield. The cause of this is that the resist is chipped due to mechanical shock in the process, and the etching solution and plating solution enter there, causing disconnection or short circuit,
Further, the chipped resist fragments adhere to the surface of the substrate in the etching solution or the plating solution, causing disconnection and short-circuit failure. In order to prevent this, it is necessary to develop an electrodeposition resist composition which is excellent in flexibility so that the resist is not chipped even by mechanical shock applied during the transportation of the substrate. Therefore, in order to solve this problem, a proposal was made to lower the Tg of the binder polymer, (2) increase the amount of the photopolymerizable unsaturated compound relative to the binder polymer, and (3) increase the molecular weight of the binder polymer. There is. As a result of studies by the present inventors, in (1) and (2), the tackiness of the resist surface becomes a problem, and in (3), the water dispersion stability of the electrodeposition solution becomes disadvantageous.

[0007]

Means for Solving the Problems As a result of intensive studies by the present inventors in order to solve the above problems, a propylene oxide chain or an ethylene oxide chain (either one or both may be used)
It was found that the flexibility of the film and the water dispersion stability of the electrodeposition liquid can be made compatible by using a bifunctional photopolymerizable unsaturated compound in which is incorporated. That is, the present invention provides (a) an acid value of 20 obtained by copolymerizing acrylic acid and / or methacrylic acid.
-300 polymer neutralized with a basic organic compound, (b) general formula (I)

[Chemical 3] (In the formula, R ₁ and R ₂ each independently represent a hydrogen atom or a methyl group, k, m, and n represent the number of repeating units, each is an integer of 0 or more, and the sum of k and m is 1; The photopolymerizable unsaturated compound containing a compound represented by the above and selected such that the sum of k, m and n is 2 to 15) and (c) a water-insoluble photoinitiator. Negative-type photosensitive electrodeposition coating resin composition, electrodeposition coating bath using the same, dipping a conductive substrate in the electrodeposition coating bath as an anode, and usually electrodeposition coating to perform electrodeposition coating on the conductive substrate A resist pattern manufacturing method characterized by forming a film, then irradiating actinic rays onto the electrodeposition coating film imagewise, photocuring the exposed part, and removing the unexposed part by development, a resist pattern Manufactured conductive substrate, method of manufacturing printed circuit board, printed circuit board and Regarding equipment.

The present invention will be described in detail below. The polymer as the component (a) is a polymer obtained by neutralizing a polymer having an acid value of 20 to 300 (polymer before neutralization) copolymerized with acrylic acid and / or methacrylic acid as an essential component with a basic organic compound. . Acrylic acid and methacrylic acid may be used alone or in combination. The amount used is appropriately used so that the acid value of the polymer before neutralization is in the range of 20 to 300. When the acid value of the polymer before neutralization is less than 20, the water dispersion stability when adding a basic organic compound and then adding water to disperse the water is poor, and sedimentation easily occurs. Further, when the acid value of the polymer exceeds 300, the appearance of the electrodeposition film becomes poor.

The polymer before neutralization is acrylic acid and / or methacrylic acid, for example, methyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, n-hexyl. Obtained by copolymerizing one or more polymerizable monomers such as acrylate, n-octyl acrylate, n-octyl methacrylate, n-decyl methacrylate, cyclohexyl methacrylate, 2-hydroxyethyl acrylate, cyclohexyl methacrylate, acrylonitrile, styrene and vinyl chloride. To be

Of these, methyl methacrylate is preferable, and in particular, the total amount of the copolymerized monomers constituting the polymer is 1
When it is used in an amount of 60 to 85 parts by weight with respect to 00 parts by weight, the adhesiveness of the resist film is eliminated, scratches are less likely to occur, and even if the resist films are stacked, they do not stick to each other. It is possible and preferable.

Synthesis of the polymer before neutralization is carried out by a general solution polymerization of the above polymerizable monomer in an organic solvent using a polymerization initiator such as azobisisobutyronitrile, azobisdimethylvaleronitrile and benzoyl peroxide. Can be obtained by In this case, the organic solvent to be used should be a hydrophilic organic solvent such as dioxane, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol monoacetate, and diethylene glycol monoethyl ether acetate, considering that it will be used for electrodeposition coating. Is preferred. If toluene,
When a hydrophobic organic solvent such as xylene or benzene is mainly used, it is necessary to distill off the solvent after the polymer synthesis and replace it with the hydrophilic solvent. The weight average molecular weight of the polymer before neutralization (standard polystyrene conversion) is 5,000 to
150,000 is preferred. If it is less than 5,000, the mechanical strength of the resist tends to be weak, and
If it exceeds, the electrodeposition coatability tends to be poor and the appearance of the coating film tends to be poor.

A basic organic compound is added to a hydrophilic organic solvent solution of the polymer (polymer precursor of the component (a)) thus obtained, which has not been neutralized, and the carboxyl contained in the polymer before neutralization is added. By neutralizing the group, the polymer of the component (a) in the present invention can be prepared.
The polymer of the component (a) of the present invention can also be prepared by adding a basic organic compound to a mixture of the polymer before neutralization, the component (b), the component (c) and the like.

The basic organic compound is not particularly limited, but examples thereof include triethylamine, monoethanolamine, diethanolamine, diisopropylamine, dimethylaminoethanol, morpholine, and the like, which are used alone or in combination of two kinds. be able to.

The amount of these basic organic compounds used is 0.3 with respect to 1 equivalent of the carboxyl group in the polymer before neutralization.
It is preferable to set to 1.0 equivalent, and it is more preferable to set to 0.4 to 1.0 equivalent. If it is less than 0.3 equivalent, the water dispersion stability of the electrodeposition coating bath tends to decrease, and if it exceeds 1.0 equivalent, the coating film thickness after electrodeposition coating tends to be thin and the appearance tends to deteriorate.

Also, basic inorganic compounds such as sodium hydroxide and potassium hydroxide are liable to be hydrolyzed in the negative photosensitive electrodeposition coating resin composition, and therefore it is preferable not to use them.

The photopolymerizable unsaturated compound which is the component (b) in the present invention contains the compound represented by the above general formula (I) as an essential component. In the general formula (I), R ₁ and R ₂ are Represents hydrogen or a methyl group, k, m and n are each an integer of 0 or more, and the sum of k and m is 1 or more and k,
The compound is selected so that the sum of m and n is 2 to 15. When the sum of k and m is 0, that is, when the ethylene oxide chain alone is in the photopolymerizable unsaturated compound, the photopolymerizable unsaturated compound is eluted out of the emulsion system. When the sum of k, m and n is less than 2, the developability deteriorates, the resist remains on the surface of the substrate in some cases, and the aqueous dispersion stability of the electrodeposition solution decreases. On the other hand, if the sum of k, m and n exceeds 15, the sensitivity will decrease. The groups of two kinds of propylene oxide groups and one kind of ethylene oxide group, which are the repeating units in the general formula (I), do not necessarily have to be present in this position at k consecutive positions, m consecutive positions, and n consecutive positions, respectively. Instead, they may exist randomly or may exist in blocks.

The compound represented by the general formula (I) can be obtained by, for example, blowing ethylene oxide or propylene oxide into water, ethylene glycol or propylene glycol and reacting them under an alkaline catalyst.

[Chemical 4] (In the formula, k, m and n have the same meanings as in the general formula (I))
To obtain a dialcohol represented by and dehydrate the dialcohol with acrylic acid or methacrylic acid, or transesterify the dialcohol with methyl acrylate or methyl methacrylate to easily produce the alcohol. You can

As the photopolymerizable unsaturated compound (b) in the present invention, other unsaturated compounds may be used in addition to the compound represented by the general formula (I) as an essential component of the component (b). it can. As the other unsaturated compound, a known compound can be used, but a compound having (d) 3 or more acryloyl groups or methacryloyl groups in one molecule is preferable from the viewpoint of high sensitivity. Examples of such (d) compound include trimethylolpropane tri (meth) acrylate, tetramethylolmethane tri (meth) acrylate, tetramethylolmethane tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipenta. Erythritol hexa (meth) acrylate, trimethylolpropane triglycidyl ether tri (meth) acrylate, the following general formula (II)

[Chemical 5] (Wherein R ₃ , R ₄ and R ₅ represent a hydrogen atom or a methyl group, and q is an integer of 1 to 10) and the like, and compounds having 3 or more unsaturated groups in one molecule. These may be used alone or in combination of two or more.

Of these, compounds having three or more unsaturated groups represented by the general formula (II) in one molecule are preferable from the viewpoints of sensitivity and water dispersion stability. Specific examples of such compounds include: Include glyceryl polyethoxypolypropoxytri (meth) acrylate, ethylene oxide-modified trimethylolpropane triacrylate (trade name TA-401 manufactured by Sanyo Kasei Co., Ltd.), trimethylolpropane polyethoxypolypropoxytri (meth) acrylate, pentaerythritol polyethoxy. Polypropoxytri (meth) acrylate, pentaerythritol polyethoxypolypropoxytetra (meth) acrylate, trimethylolethane polyethoxypolypropoxytri (meth)
Arylate, dipentaerythritol polyethoxypolypropoxytri (meth) acrylate, dipentaerythritol polyethoxypolypropoxytetra (meth) arylate, dipentaerythritol polyethoxypolypropoxypenta (meth) arylate, dipentaerythritol polyethoxypolypropoxyhexa ( (Meth) arylate and the like can be mentioned, and these can be used alone or in combination of two or more kinds. The amount of the component (d) used is preferably 90 parts by weight or less, and more preferably 70 parts by weight or less, based on 100 parts by weight of the total amount of the component (b). .

Examples of the water-insoluble photoinitiator (c) in the present invention include benzophenone, N, N'-tetramethyl-4,4'-diaminobenzophenone, 4-methoxy-4'-dimethylaminobenzophenone, 2 -Aromatic ketones such as ethylanthraquinone and phenanthrenequinone, benzoin methyl ether, benzoin ethyl ether, benzoin ether such as benzoin phenyl ether, benzoin such as methylbenzoin and ethylbenzoin, 2- (o-chlorophenyl) -4,5 -Diphenylimidazole dimer, 2- (o-chlorophenyl)-
Examples include 4,5-di (m-methoxyphenyl) imidazole dimer and 2,4-di (p-methoxyphenyl) -5-phenylimidazole dimer, which may be used alone or in combination of two or more. Can be used.

The amount of the polymer used as the component (a) is 50 based on 100 parts by weight of the total amount of the components (a) and (b).
˜85 parts by weight, more preferably 60 to 75 parts by weight. When the amount used is less than 50 parts by weight, the mechanical strength of the resist tends to be weak, and when it exceeds 85 parts by weight, the proportion of the photopolymerizable unsaturated compound as the component (b) decreases and the sensitivity to light decreases. Tend to do.

The amount of the component (b) used is (a) and (b)
The total amount of the components is preferably 15 to 50 parts by weight, more preferably 25 to 40 parts by weight, based on 100 parts by weight. If the amount used is less than 15 parts by weight, the sensitivity to light tends to decrease, and if it exceeds 50 parts by weight, the resist tends to become brittle.

The amount of the compound represented by the general formula (I) used is 10 to 100 relative to 100 parts by weight of the total amount of the component (b).
Parts by weight is preferable, 20 to 100 parts by weight is more preferable, 30 to 100 parts by weight is particularly preferable, and 40 to 100
Highly preferred is parts by weight.

The amount of the component (c) used is preferably 0.1 to 15 parts by weight, and 0.2 to 10 parts by weight, based on 100 parts by weight of the total amount of the components (a) and (b). Is more preferable. If the amount used is less than 0.1 parts by weight, the sensitivity to light tends to decrease, and if it exceeds 15 parts by weight, the light absorption on the surface of the composition increases during exposure, resulting in insufficient internal photocuring. Tends to become.

The component (c) must be water-insoluble.
If it is water-soluble, it becomes difficult to perform electrodeposition coating in a state of being uniformly mixed with other components.

The negative photosensitive electrodeposition coating resin composition of the present invention may contain a coloring agent such as a dye or a pigment. Examples of the colorant include fuchsin, auramine base, crystal violet, Victoria pure blue, malachite green, methyl orange, acid violet R.
RH or the like is used.

Further, a thermal polymerization inhibitor, a plasticizer, an adhesion promoter, an inorganic filler and the like may be added to the negative photosensitive electrodeposition coating resin composition of the present invention.

The electrodeposition coating bath can be usually prepared by adding water to a negative photosensitive electrodeposition coating resin composition and dissolving or dispersing it in water. The solid content of the electrodeposition coating bath is 5 to 2
From the viewpoints of bath management, electrodeposition properties, etc., it is preferable that the content is 0 wt% and the pH is in the range of 6.0 to 9.0 at 25 ° C. The pH may be adjusted later by adding the basic organic compound in order to adjust the pH to the above preferable range.

Further, in order to improve the water dispersibility and dispersion stability of the electrodeposition coating bath containing the negative photosensitive electrodeposition coating resin composition, a nonionic surfactant, a cationic surfactant and an anionic surfactant are used. Agents and the like can be added as appropriate.

Hydrophobic solvents such as toluene, xylene, and 2-ethylhexyl alcohol can be appropriately added to increase the coating amount during electrodeposition coating.

In order to carry out electrodeposition coating on a conductive substrate using the electrodeposition coating bath thus obtained, the conductive substrate is immersed as an anode in the electrodeposition coating bath, and usually 50 to 400 V is applied.
Is applied for 10 seconds to 5 minutes. The film thickness of the obtained coating film is preferably 5 to 50 μm. The temperature of the electrodeposition coating bath at this time is preferably controlled to 15 to 30 ° C.

After the electrodeposition coating, the article to be coated is pulled 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, the coating film is thermally cured, and a part of the film remains undeveloped in the developing step after exposure.

On the electrodeposition coating film thus obtained, a film of a water-soluble polymer such as polyvinyl alcohol is used in an amount of about 1 in order to protect the film and prevent the inhibition of curing by oxygen during the next exposure. You may form with a film thickness of about 10 micrometers.

Then, the coating film is irradiated with an actinic ray in an image-like manner, the exposed portion of the coating film is photocured, and the unexposed portion is removed by development to obtain a photocured resist pattern. As a light source for actinic rays, wavelength 300-450 nm
Those which emit the light of, for example, mercury vapor arc, carbon arc, xenon arc and the like are preferably used.

The development can be carried out by spraying an alkaline aqueous solution using sodium hydroxide, sodium carbonate, potassium hydroxide or the like, or by immersing in an alkaline aqueous solution.

[0036]

The present invention will be described with reference to the following examples. In addition,
The photopolymerizable unsaturated compounds a to d mean compounds in which the symbols in the general formula (I) represent those shown in Table 1.

[Table 1] Example 1 1,130 g of propylene glycol monopropyl ether was added to a flask equipped with a stirrer, a reflux condenser, a thermometer, a dropping funnel and a nitrogen gas introducing tube, and the mixture was stirred and heated to 100 ° C. while blowing nitrogen gas. When the temperature became constant at 100 ° C, 3 parts of a liquid prepared by mixing 185 g of methacrylic acid, 595 g of methyl methacrylate, 214 g of ethyl acrylate and 10 g of azobisisobutyronitrile was used.
The mixture was dropped into the flask over a period of time and then kept at 100 ° C. for 3.5 hours while stirring. After 3.5 hours, a solution prepared by dissolving 5 g of azobisdimethylvaleronitrile in 100 g of propylene glycol monopropyl ether was dropped into the flask over 10 minutes, and then the mixture was again kept at 90 ° C. for 4 hours while stirring.

The polymer as a precursor of the component (a) thus obtained has a weight average molecular weight of 35,000.
The acid value was 0 and the acid value was 120. The solid content of the polymer solution was 45.3% by weight.

Next, 650 g of this polymer solution was added with 200 g of the photopolymerizable unsaturated compound a as the component (b), and (c).
30 g of benzophenone as a component, 1 g of N, N'-tetraethyl-4,4'-diaminobenzophenone and 100 g of propylene glycol monomethyl ether were added and dissolved, and 35 g of triethylamine as a basic organic compound was added and further dissolved in this solution. The polymer of the precursor of the component (a) in the solution was neutralized.

Next, while stirring this solution, 4,700 g of ion-exchanged water was gradually added dropwise to obtain an electrodeposition coating bath. The solid content of this electrodeposition coating bath is 10% by weight, pH
Was 7.5 at 25 ° C.

Example 2 Propylene glycol monopropyl ether 1,13 was placed in a flask equipped with a stirrer, a reflux condenser, a thermometer, a dropping funnel and a device similar to that of Example 1 equipped with a nitrogen gas introducing tube.
90 g while adding 0 g and blowing nitrogen gas with stirring
Warmed to a temperature of ° C. When the temperature became constant at 90 ° C, 169 g of methacrylic acid and 24 of methyl methacrylate
2 g, n-butyl acrylate 370 g, ethyl methacrylate 219 g and azobisisobutyronitrile 10
The liquid in which g was mixed was dropped into the flask over 2.5 hours, and then the mixture was kept at 90 ° C. for 3 hours while stirring. After 3 hours, 3 g of azobisisobutyronitrile was added to 1 of dioxane.
The solution dissolved in 00 g was dropped into the flask over 10 minutes, and then the temperature was kept at 90 ° C. for 4 hours with stirring.

The polymer as a precursor of the component (a) thus obtained has a weight average molecular weight of 55,000.
The acid value was 0 and the acid value was 111. The solid content of the polymer solution was 46.3% by weight.

Next, (b) was added to 635 g of this polymer solution.
42 g of photopolymerizable unsaturated compound b as a component and 84 g of ethylene oxide-modified trimethylolpropane triacrylate (manufactured by Sanyo Kasei Co., Ltd., trade name TA-401),
30 g of benzophenone and N, N 'as component (c)
-Tetraethyl-4,4'-diaminobenzophenone 1
g was added and dissolved.

To this solution, 32.0 g of diethylamine as a basic organic compound was added and dissolved to neutralize the precursor polymer of the component (a) in the solution. Next, while stirring this solution, 4,300 g of ion-exchanged water was gradually added dropwise to obtain an electrodeposition coating bath. The electrodeposition coating bath had a solid content of 10% by weight and a pH of 7.5 at 25 ° C.

Example 3 To a flask equipped with the same apparatus as in Example 1, 1,130 g of ethyl cellosolve was added and stirred, and the mixture was heated to 90 ° C. while blowing nitrogen gas. When the temperature became constant at 90 ℃, methacrylic acid 198g, methyl methacrylate 3
52 g, ethyl acrylate 290 g, methyl methacrylate 160 g and azobisisobutyronitrile 10 g
The mixed solution of was added dropwise to the flask over 2 hours. Then, the mixture was kept at 90 ° C. for 3 hours while stirring. After 3 hours, 3 g of azobisisovaleronitrile was added to 100 g of dioxane.
The solution dissolved in was added dropwise to the flask over 10 minutes, and then the temperature was maintained at 90 ° C. for 4 hours while stirring again.

The polymer as a precursor of the component (a) thus obtained had a weight average molecular weight of 44,000.
The acid value was 0 and the acid value was 129. The solid content of the polymer solution was 46.2% by weight.

Next, 700 g of this polymer solution was added to (b)
145 g of a photopolymerizable unsaturated compound c as a component,
33 g of benzophenone and N, N 'as component (c)
-Tetraethyl-4,4'-diaminobenzophenone 0.8 g was added and dissolved, and 40 g of triethylamine as a basic organic compound was added to this solution to neutralize the polymer of the precursor of the component (a) in the solution, Further, 100 g of n-butanol was added and dissolved.

Next, while stirring this solution, 4,800 g of ion-exchanged water was gradually added dropwise to obtain an electrodeposition coating bath. The solid content of this electrodeposition coating bath is 10% by weight, pH
Was 7.4 at 25 ° C.

Example 4 1,130 g of propylene glycol monopropyl ether was added to a flask equipped with the same apparatus as in Example 1, stirred and heated to 90 ° C. while blowing nitrogen gas. When the temperature became constant at 90 ° C, acrylic acid 148
g, 620 g of methyl methacrylate, 122 g of n-propyl acrylate, 110 g of methyl acrylate, and 5 g of azobisisobutyronitrile were added dropwise into the flask over 2 hours, and then the mixture was kept at 90 ° C. for 3 hours while stirring. After 3 hours, 1 g of azobisisobutyronitrile was dissolved in 100 g of ethyl cellosolve to prepare 1 solution.
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 weight average molecular weight of the polymer thus obtained as the precursor of the component (a) is 57,000.
The acid value was 0 and the acid value was 116. The solid content of the polymer solution was 47.1% by weight.

Next, in 600 g of this polymer solution, 125 g of the photopolymerizable unsaturated compound d as the component (b), 68 g of pentaerythritol tetraacrylate (trade name SR-295 manufactured by Sartomer Company), and the component (c). Benzophenone as a base and 1 g of N, N'-tetraethyl-4,4'-diaminobenzophenone as a base are dissolved therein, and 30 g of triethylamine as a basic organic compound is dissolved in the solution to prepare a precursor of the component (a) in the solution. The body polymer was neutralized. Next, while stirring this solution, 3,400 g of ion-exchanged water was gradually added dropwise to obtain an electrodeposition bath. The solid content of this electrodeposition coating bath was 10% by weight, and the pH was 7.7 at 25 ° C.

Comparative Example 1 The same material as in Example 1 except that 112 g of ethylene oxide-modified bisphenol A diacrylate (manufactured by Sartomer Company, trade name SR-349) was used in place of the component (b). By the method, an electrodeposition coating bath was obtained.

Comparative Example 2 Instead of the component (b) in Example 1, trimethylolpropane triacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name U)
An electrodeposition coating bath was obtained by using 120 g of NK ester A-TMPT) with the same materials and method.

Glass epoxy copper clad laminates (Hitachi Chemical Co., Ltd.) were used in each of the electrodeposition coating baths of Examples 1 to 4 and Comparative Examples 1 and 2.
Manufactured by MCL-E-61) (200 mm x 75 mm) as an anode, stainless steel plate (SUS304) (shape 200 mm x
75 mm × 1 mm) is immersed as a cathode, and a DC voltage is applied for 3 minutes at a temperature of 25 ° C.
A 16 μm electrodeposition coating film (photosensitive film) was formed. After this,
After washing with water and draining, it was dried at 80 ° C. for 15 minutes.

The photosensitive film formed in order to evaluate the flexibility of the photosensitive film was exposed to a light amount of 100 mJ / cm ^{2 with} a 3 kW ultra-high pressure mercury lamp, developed with a 1 wt% sodium carbonate aqueous solution, and then a 1 mm square cross cut. A cross cut test was performed using a gauge. The evaluation criteria for the cross-cutting property test are ◎; the cuts are smooth and there are no defects, ○: the area of the defect is within 5% of the total square area, Δ: the area of the defect is 5 to 25% of the total square area, ×: 25% of the total square area of the defective area
That's it. Further, in order to evaluate the water dispersion stability, the electrodeposition solutions of Examples 1 to 4 and Comparative Examples 1 and 2 were stored at 25 ° C. in a constant temperature bath, and the presence or absence of emulsion precipitation was visually observed.
Table 2 shows the evaluation results of flexibility and water dispersion stability in Examples 1 to 4 and Comparative Examples 1 and 2.

[0055]

[Table 2] In each of Examples 1 to 4, the cross cut property and the water dispersion stability were good. On the other hand, in the cases of Comparative Examples 1 and 2, it is found that both flexibility and water dispersion stability cannot be achieved at the same time. The resist patterns of Examples 1 to 4 obtained after development had a good resist shape.

[0056]

The negative electrodeposition coating resin composition of the present invention is capable of forming a photosensitive film having high flexibility and is excellent in water dispersion stability. According to the invention, a high density,
A high-precision printed circuit board can be obtained, and this printed circuit board can be suitably used for various devices such as a television, an audio, a microcomputer, a personal computer, a communication device, a measuring instrument, a controller, and a game machine.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI Technical indication location G03F 7/30 7124-2H (72) Inventor Hideaki Uehara 4-13-1, Higashimachi, Hitachi City, Ibaraki Prefecture Hitachi Chemical Co., Ltd. in Ibaraki Laboratory (72) Inventor Shigeo Tachiki 4-13-1, Higashimachi, Hitachi City, Ibaraki Hitachi Chemical Co., Ltd. in Ibaraki Laboratory (72) Inventor Takuro Kato 4, Higashimachi, Hitachi City, Ibaraki Prefecture 13-1 Hitachi Chemical Co., Ltd. Yamazaki Plant (72) Inventor Katsushige Tsukada 4-13-1, Higashimachi, Hitachi City, Ibaraki Prefecture 13-12 Hitachi Chemical Co., Ltd. Yamazaki Plant (72) Inventor Yuji Yamazaki Otawara, Tochigi Prefecture 1382-12 Shimoishigami, Ichi, Japan Nasu Plant, Dainippon Paint Co., Ltd. (72) Inventor, Shoji Yamada 1382-1212 Shimoishigami, Otawara, Tochigi Dainippon Paint Co., Ltd. Nasu (72) Inventor Toshihiko Shiotani 1382-12 Shimoishigami, Otawara-shi, Tochigi Dainippon Paint Co., Ltd.Nasu factory (72) Inventor Yoshihisa Nagashima 1382-12 Shimoishi, Otawara-shi, Tochigi Dainippon Paint Co., Ltd.Nasu factory Within

Claims (9)

[Claims] 1. (a) A polymer obtained by neutralizing 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) a general formula (I): (In the formula, R ₁ and R ₂ each independently represent a hydrogen atom or a methyl group, k, m, and n represent the number of repeating units, each is an integer of 0 or more, and the sum of k and m is 1; The photopolymerizable unsaturated compound containing a compound represented by the above and selected such that the sum of k, m and n is 2 to 15) and (c) a water-insoluble photoinitiator. Negative-type photosensitive electrodeposition coating resin composition. 2. The negative photosensitive electrodeposition coating resin composition according to claim 1, which further contains (d) a compound having (d) a compound having three or more acryloyl groups or methacryloyl groups in one molecule. . 3. (d) A compound having three or more acryloyl groups or methacryloyl groups in one molecule is represented by the general formula (I
I) [Chemical 2] (Wherein R ₃ , R ₄ and R ₅ each independently represent a hydrogen atom or a methyl group, and q is an integer of 1 to 10) and 3 or more unsaturated groups are contained in one molecule. The negative photosensitive electrodeposition coating resin composition according to claim 2, which is a compound having: 4. An electrodeposition coating bath containing the negative type photosensitive electrodeposition coating resin composition according to claim 1 or 2. 5. A conductive substrate is immersed as an anode in the electrodeposition coating bath according to claim 4, and electrodeposition coating is performed by energization to form an electrodeposition coating film on the conductive substrate, after which actinic rays are applied to the electrodeposition. A method for producing a resist pattern, which comprises irradiating an image on a coating film for coating, photo-curing the exposed part, and removing the unexposed part by development. 6. A conductive substrate having a resist pattern manufactured by the manufacturing method according to claim 5. 7. A method of manufacturing a printed circuit board, which comprises etching and / or plating the conductive substrate having the resist pattern of claim 6. 8. A printed circuit board manufactured by the method for manufacturing a printed circuit board according to claim 7. 9. A device using the printed circuit board according to claim 8.