JP2758039B2 - Visible light-sensitive electrodeposition coating composition and image forming method using the same - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a composition for visible light-sensitive electrodeposition paint and an image forming method using the composition for electrodeposition paint.

[Prior art and its problems] Photosensitive compositions are widely used in various applications such as photoresists, plate materials for planographic or letterpress printing, PS plates for offset printing, information recording materials, and relief image forming materials.

These photosensitive composition is often sensitive to ultraviolet light, its sensitivity generally require high power light source for a few tens to several hundreds mJ / cm ^2, yet of poor conversion efficiency of energy for recording There's a problem. On the other hand, there is also a method of forming an image by directly drawing using a high energy density light source such as a laser. In this case, not only the advantage that energy conversion efficiency is improved but also the image forming process is greatly simplified. There is an advantage that you can. In this case, it is more advantageous to use a visible laser capable of obtaining a stable oscillation line in terms of life and intensity than using an ultraviolet laser as a scanning exposure light source for direct writing. For this reason, the emergence of a visible light-sensitive composition having a sensitivity that allows scanning exposure with a visible laser is desired, and a high sensitivity to an Ar ⁺ laser having a stable oscillation line in the visible region of a wavelength of 488 nm is desired. Many visible light-sensitive compositions have been proposed (for example,
JP-A-62-31848, JP-A-61-233736, JP-A-60-221403, Abstracts of the 1st Annual Conference of the Printed Circuit Society of Japan, 91 pages, Printed Circuit World Convention IV.technical pape
r-2 etc.).

The form of these visible light-sensitive compositions is liquid or film-like, but has the following drawbacks: Liquid visible light-sensitive compositions have difficulty forming a uniform and smooth film. There are many problems in terms of workability, such as difficulty in coating to a desired film thickness and inability to uniformly coat a complex shape. Further, the liquid visible light-sensitive composition has a problem in safety and health that it is harmful to the human body because of a large content of the organic solvent.

On the other hand, the visible light-sensitive film formed into a film has a thickness of several tens of μm, so that an image formed by light irradiation is not clear, and it is difficult to uniformly adhere the film to the conductor surface without gaps. There is a problem that the film is expensive because the film cannot be used effectively (loss occurs).

For this reason, the appearance of a visible light-sensitive composition that solves the above problems is strongly desired.

[Means for Solving the Problems] The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, the present inventors have found that they comprise a photocurable resin, a specific spectral sensitizer, and a water-insoluble polymerization initiator. The electrodeposition coating composition solves the above-mentioned problems, and a composition in which a specific nitrogen-containing compound is added to the electrodeposition coating composition can provide higher sensitivity and form a high-resolution image. The inventors have found that the present invention can be performed, and have completed the present invention.

Thus, according to the present invention, (A) a photocurable resin containing a photosensitive group and an ionic group which can be crosslinked or polymerized by light irradiation (hereinafter, also referred to as “photocurable resin”); A) a spectral sensitizer which is excited by absorption of visible light and has an interaction with the photocurable resin (A); (C) a water-insoluble polymerization initiator; and (D) if necessary. Furthermore, the following general formulas (1) to
(6) In the formula, X represents a hydrogen atom or a hydroxyl group; R ₁ , R ₂ and R ₃ each represent a hydrogen atom, a chlorine atom or an alkyl group having 1 to 6 carbon atoms; In the formula, R ₄ and R ₅ each represent a hydrogen atom or a carbon number 1 to
Represents an alkyl group of 6, In the formula, R ₆ , R ₇ and R ₈ each represent a hydrogen atom, a hydroxyl group or an alkyl group having 1 to 12 carbon atoms; In the formula, R ₉ , R ₁₀ and R ₁₁ each represent a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms, In the formula, R ₁₂ represents a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms, In the formula, R ₁₃ and R ₁₄ each represent a hydrogen atom or a carbon atom 1
A visible light-sensitive electrodeposition coating composition comprising at least one nitrogen-containing compound selected from the group consisting of an alkyl group of from 12 to 12, and n is an integer of from 1 to 3. .

According to the present invention, further, (i) the electrodeposition coating composition is electrodeposited on a conductor surface, and (ii) the exposed electrodeposition coating film is exposed by partially irradiating visible light. And (iii) an image forming method characterized in that the unexposed portion is removed by contact with a developing solution.

 Hereinafter, the present invention will be described in more detail.

(A) Photocurable resin The photocurable resin (A) used in the present invention includes:
A polymer soluble in an aqueous alkali or acid solution containing a photosensitive group and an ionic group, that is, an anionic or cationic group, capable of undergoing a crosslinking reaction or a polymerization reaction upon irradiation with light. Photocurable polymers that are substantially insoluble or hardly soluble in an aqueous alkali solution or acid solution through a crosslinking reaction or polymerization reaction are included.

The photosensitive group that may be present in the photocurable resin (A) is
It is a group capable of initiating crosslinking or polymerization reaction by light irradiation in the presence of the spectral sensitizer (B) and the water-insoluble polymerization initiator (C), and specific examples of the photosensitive group having such characteristics. Examples include, for example, a (meth) acryloyl group [CH
₂ = CR-CO- (R represents a hydrogen atom or a methyl group)], a cinnamoyl group, an allyl group and the like.

The photocurable resin (A) contains the above-mentioned anionic or cationic ionic group in addition to the photosensitive group. The amounts of the ionic group and the photosensitive group can be varied over a wide range depending on the type and molecular weight of the polymer to be used as a substrate. The curable resin has an acid value of 20 to 300 (mgKOH / g
The amount of the cationic group (for example, tertiary amino group or onium base) is usually 0.2 to 5 mol / kg resin, preferably 0.3 to 0.3 mol / kg.
~ 2.0 mol / kg resin amount, and the photosensitive group is
Suitably it is included in an amount of 0.2 to 5.0 mol / kg resin, preferably 0.7 to 4.5 mol / kg resin.

The photocurable resin (A) is generally 300 to 100,000, preferably 1,000 to 50,000, and more preferably 3,000 to 30,000.
The glass transition temperature (Tg) is preferably 0 ° C. or more, particularly in the range of 5 to 70 ° C.

When the ionic group of the photocurable resin is less than the lower limit of the above range, the resin cannot be generally made water-soluble or water-dispersible, and it becomes difficult to form an electrodeposition coating composition, and the upper limit is also set. If it exceeds, the electrodeposition paint becomes difficult to be applied to the substrate, and a large amount of electric power tends to be required to increase the amount of application.

Further, when the number-average molecular weight of the photocurable resin is less than 300, the coating film to be applied during electrodeposition coating is easily broken, and it tends to be difficult to obtain a uniform coating film.
If it exceeds 000, the electrodeposition coating film tends to have poor smoothness and a rough coated surface, and the image resolution tends to be poor.

Further, when the Tg of the photocurable resin is lower than 0 ° C., the electrodeposition coating film generally exhibits tackiness, and dust and the like tend to adhere to the coating film, making it difficult to handle.

Hereinafter, the anionic photocurable resin (A) used in the present invention will be specifically described.

(I) Photocurable resin containing (meth) acryloyl group as photosensitive group: The present photocurable resin can be produced, for example, by adding a glycidyl group-containing unsaturated compound to a high acid value acrylic resin. it can. The high acid value acrylic resin used at that time contains, for example, an α, β-ethylenically unsaturated acid such as acrylic acid or methacrylic acid as an essential component, and further contains (meth) acrylic acid esters such as methyl ( Meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, hydroxyethyl (meth) acrylate, and styrene;
It is obtained by copolymerizing at least one unsaturated monomer selected from (meth) acrylonitrile, (meth) acrylamide and the like. Here, the α, β-ethylenically unsaturated acid generally has an acid value of an acrylic resin of 40 to 650,
Preferably, it can be used in such an amount as to be in the range of 60 to 500. Further, the number average molecular weight and glass transition temperature (Tg) of the high acid value acrylic resin are such that the photocurable resin obtained by adding a glycidyl group-containing unsaturated compound to the acrylic resin has the above-mentioned number average molecular weight and Tg. Is appropriately adjusted to have

On the other hand, as the glycidyl group-containing unsaturated compound to be added to the high acid value acrylic resin, specifically,
Glycidyl acrylate, glycidyl methacrylate and the like can be mentioned.

The addition reaction between the high acid value acrylic resin and the glycidyl group-containing unsaturated compound is performed according to a method known per se,
For example, it can be easily carried out by reacting at 80 to 120 ° C. for 1 to 5 hours using a catalyst such as tetraethylammonium bromide.

The photocurable resin can also be obtained by adding a reaction product of a hydroxy group-containing polymerizable unsaturated compound and a diisocyanate compound to a hydroxyl group-containing high acid value acrylic resin described in the section (ii). Can be manufactured.

Examples of the hydroxyl group-containing polymerizable unsaturated compound include 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, N-methyl acrylamide, and the like. Examples include isocyanate, xylylene diisocyanate, hexamethylene diisocyanate, lysine diisocyanate, and the like.

(Ii) Photocurable resin containing a cinnamoyl group as a photosensitive group: The photocurable resin includes, for example, a high acid value acrylic resin containing a hydroxyl group and a substituted or unsubstituted cinnamic acid halide. It can be produced by reacting in the presence of a base, for example, in a pyridine solvent. The hydroxyl group-containing high acid value acrylic resin used at that time contains, as essential components, the α, β-ethylenically unsaturated acid and the hydroxyl group-containing polymerizable unsaturated compound described in the above section (i), At least one of the other unsaturated monomers
It can be obtained by copolymerizing with a seed.

In the production of such a hydroxyl group-containing high acid value acrylic resin, generally, the obtained photocurable resin has an acid value of 20.
To 300, preferably 30 to 100, and can be used in an amount such that the hydroxyl group-containing polymerizable unsaturated compound of the ethylenically unsaturated acid is generally the high acid value acrylic resin. It can be used in an amount of 5 to 97 parts by weight, preferably 20 to 75 parts by weight, per 100 parts by weight.

On the other hand, the substituted or unsubstituted cinnamic acid halide is generally the above hydroxyl group-containing high acid value acrylic resin 100.
It can be used in an amount such that it is in the range of 6 to 180 parts by weight, preferably 30 to 140 parts by weight per part by weight.

Examples of the substituted or unsubstituted cinnamate halide that can be used include a cinnamate halide which may have 1 to 3 substituents selected from a nitro group and a lower alkoxy group on a benzene ring, More specifically, cinnamic acid chloride, p-nitrocinnamic acid chloride, p-methoxycinnamic acid chloride, p-ethoxycinnamic acid chloride and the like can be mentioned.

The reaction between these substituted or unsubstituted cinnamic acid halides and the above-mentioned hydroxy group-containing acrylic resin is carried out, for example, by adding 100 to 100 parts by weight of pyridine to 100 parts by weight of an acrylic resin solution, and adding 20 to 100 parts by weight of dimethylformamide. The dissolved cinnamic acid chloride is added dropwise at 10 ° C or less, and then 30 ~
It is obtained by stirring at 70 ° C. for 3-8 hours. The purified product can be obtained by pouring the reaction solution into a large excess of methanol to precipitate the polymer, reprecipitating the mixture with a mixture of tetrahydrofuran and water, and further reprecipitating the mixture with a mixture of tetrahydrofuran and methanol.

(Iii) Photo-curable resin containing an ant group as a photosensitive group: The photo-curable resin may be, for example, allyl glycidyl ether in addition to the high acid value acrylic resin used in item (i). Or by adding a reactant of (meth) allyl alcohol and a diisocyanate compound to a hydroxyl group-containing high acid value acrylic resin.

The above-mentioned addition reaction between the high acid value acrylic resin and allyl glycidyl ether can be carried out in the same manner as in the method described in the above (i).

Further, in the photosensitive electrodeposition coating composition of the present invention, a cationic type electrodeposition coating composition can be obtained by using a conventionally known cationic resin in addition to the anionic resin as the photocurable resin (A). It is.

Examples of such a cationic resin include a resin obtained by adding a reactant of a hydroxyl group-containing polymerizable unsaturated compound and a diisocyanate compound to an acrylic resin having a hydroxyl group and a tertiary amino group; Tertiary amino group-containing resin obtained by reacting the remaining epoxy group with a polymerizable unsaturated monocarboxylic acid or a hydroxy group-containing unsaturated compound after reacting with a tertiary amine; glycidyl group-containing unsaturated compound and tertiary amino A tertiary amino group obtained by reacting a polymerizable unsaturated monocarboxylic acid or a hydroxyl group-containing polymerizable unsaturated compound with a resin obtained by copolymerizing a group-containing unsaturated compound with another polymerizable unsaturated monomer. The epoxy resin is reacted with a polymerizable unsaturated monocarboxylic acid or a hydroxyl group-containing unsaturated compound to obtain a residual epoxy resin. An onium base-containing resin obtained as an onium chloride in the presence of a tertiary amino compound, thioether, phosphine, or the like and a carboxylic acid can be used. These resins may be used alone or in combination of two or more. Can be.

(B) Spectral sensitizer The spectral sensitizer (B) used in the visible light-sensitive electrodeposition coating composition of the present invention is excited by absorbing light (visible light) in a wavelength region of 400 to 700 nm. And the above-mentioned photocurable resin (A) and the water-insoluble polymerization initiator (C) described below.
Such as thioxanthene, xanthene, ketone, thiopyrylium salt, basestyryl, merocyanine, 3-substituted coumarin, cyanine, acridine, and thiazine dyes And the like. The term "interaction" as used herein includes energy transfer, electron transfer, and the like from the excited spectral sensitizer (B) to the photocurable resin (A) or the water-insoluble polymerization initiator (C). You.

The amount of the spectral sensitizer (B) used depends on its type, the type of the photocurable resin to be interacted with, and / or the type of the water-insoluble polymerization initiator (C), and must be strictly defined. Is difficult, but generally speaking, the resin (A) has a solid content of 100
A suitable range is 0.1 to 10 parts by weight, preferably 0.3 to 5 parts by weight per part by weight. The amount of the spectral sensitizer (B) used is 0.1
If the amount is less than 10 parts by weight, the photosensitivity of the formed film is undesirably reduced.If the amount is more than 10 parts by weight, it tends to be difficult to keep the spectral sensitizer in the composition in a uniform state. Can be

Specific examples of the spectral sensitizer (B) that can be used in the present invention are as follows.

(I) Xanthene and thioxanthene dyes: In the formula, A is an oxygen atom or a sulfur atom; X ₁ and X ₂ are each a hydrogen atom or a halogen atom such as chlorine or bromine; Y ₁ is a carbon atom or a nitrogen atom (provided that Y ₁ is a carbon atom In some cases, a double bond is present between adjacent carbon atoms (at a point indicated by a dotted line), and when Y ₁ is a nitrogen atom, a single bond is present between adjacent carbon atoms. Z is an oxygen atom (in this case, a double bond between adjacent carbon atoms), a lower alkoxy group or a lower alkanoyloxy group; R ₂₁ is a lower alkyl group, a hydroxy lower alkyl group, a lower alkoxy lower alkyl group group, a di-lower alkylamino-lower alkyl group or an aryl group; R ₂₂ is a lower alkoxy group or a di-lower alkylamino group, in xanthene or Chiokinten based dyes represented Kill (e.g., see JP-A-62-31848).

(Ii) Ketone dyes: Wherein R ₂₃ represents a lower alkyl group such as methyl and ethyl; R ₂₄ represents a hydrogen atom or And ketone dyes represented by the following.

(Iii) Thiopyrylium salt dyes: Where R_{twenty five}, R₂₆, R₂₇Are each independently a hydrogen atom, halo
Gen atom, alkyl group, haloalkyl group, ethylenyl
Group, styryl group, alkoxy group, phenyl group, naphthyl
Group, alkylphenyl group, alkoxyphenyl group, hydr
Roxyphenyl group, halophenyl group, nitrophenyl
Group, aminophenyl group, nitro group, amino group or hydroxyl group
X;_ThreeRepresents an oxygen atom or a sulfur atom; Y_Two Is
A pyrylium salt or a thiopyrylium salt, which represents an anionic functional group,
Can be Y_TwoAs an anionic functional group represented by
For example, perchlorate, fluoroborate, chloro
Aluminate, chlorophthalate, sulfur acetate
G, metsulfate, fluoroantimonate, thio
Cyanate and the like (for example, JP-A-61-213838).
Reference).

(Iv) Base styryl dyes: And a basestyryl dye represented by the following formula:

(V) Merocyanine dyes: In the formula, R ₂₈ and R ₂₉ each represent a hydrogen atom or a carbon atom
4 represents an alkyl group; n represents an integer of 1 to 3; In the formula, X ₆ and X ₇ are a sulfur atom, an oxygen atom, respectively. R ₃₀ , R ₃₁ and R ₃₂ each represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms or an aryl group; In the formula, R ₃₀ , R ₃₁ and R ₃₂ each represent a hydrogen atom and a carbon atom of 1
And X ₈ represents a hydrogen atom or an alkali metal, and examples thereof include merocyanine dyes represented by the following formula (for example, see JP-A-61-213838).

(Vi) 3-substituted coumarins: The following structural formula (See JP-A-61-97650).

(Vii) Cyanine dyes: In the formula, R ₃₃ is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms,
An aryl group, an alkoxy group or a dialkylamino group; R ₃₄ represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms or an aryl group; X ₉ represents a halogen atom; n represents an integer of 1 to 3 . Y ₃ In the formula, R ₃₅ and R ₃₆ each independently represent a hydrogen atom,
X ₁₀ represents an alkyl group or an aryl group; X ₁₀ represents a halogen atom; In the formula, R ₃₇ is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms,
R ₃₈ represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms or an aryl group; X ₁₁ represents a halogen atom; n represents an integer of 1 to 3; And the cyanine dye represented by the following formula (JP-A-61-213838).

(C) Wastewater-soluble polymerization initiator The visible light-sensitive electrodeposition coating composition of the present invention contains a water-insoluble polymerization initiator. The initiator is decomposed by irradiating light and initiates a crosslinking reaction or a polymerization reaction of the photosensitive group of the photocurable resin.

As such a polymerization initiator, a substance which decomposes by itself upon photoexcitation or by the interaction with the above-mentioned spectral sensitizer (B), more specifically, by its own cleavage reaction or from other molecules, By hydrogen abstraction reaction,
In the present invention, a compound which generates a group active for a crosslinking reaction or a polymerization reaction of the photosensitive group, and which is particularly substantially insoluble in water (for example, having a solubility in water of 2 g / 100 g).
ml water or less) is used. By using such a water-insoluble polymerization initiator, it can be efficiently precipitated during electrodeposition coating and contained in the coating film to form a highly sensitive coating film.

Specific examples of such a polymerization initiator include the following.

Aromatic carbonyl compounds such as benzophenone, benzoin methyl ether, benzoin isopropyl ether, benzyl, xanthone, thioxanthone and anthraquinone; acetophenone, propiophenone, α-hydroxyisobutylphenone, α, α'-dichloro-4-phenoxyacetoph Acetophenones such as enone, 1-hydroxy-1-cyclohexylacetophenone and acetophenone; benzoyl peroxide, tertiary butyl-peroxybenzoate, tertiary butyl-peroxy-2-ethylhexanoate, tertiary butyl hydroperoxide Organic peroxides such as tert-butylbutylperoxyisophthalate, 3,3 ', 4,4'-tetra (tert-butylperoxycarbonyl) benzophenone; Diphenylhalonium salts such as diphenyliodonium bromide and diphenyliodonium chloride; organic halides such as carbon tetrachloride, carbon tetrabromide, chloroform and iodoform; 3-phenyl-5-isoxazolone, 2,4,6- Heterocyclic and polycyclic compounds such as tris (trichloromethyl) -1,3,5-triazinebenzanthrone; 2,2'-azobis (2,4-dimethylvaleronitrile) 2,
Azo compounds such as 2'-azobisisobutyronitrile, 1,1'-azobis (cyclohexane-1-carbonitrile), and 2,2'-azobis (2-methylbutyronitrile); iron-allene complexes (Iron -Arene Complex: see European Patent No. 152377); titanocene compounds (see JP-A-63-221110);
etc.

Among the above water-insoluble polymerization initiators, ditertiary butyl diperoxyisophthalate, 3,3 ′, 4,4′-
Tetra (tertiarybutylperoxycarbonyl) benzophenone, iron-allene complex and titanocene compounds are preferred compounds because of their high activity for crosslinking or polymerization.

Above all, the iron-allene complex and the titanocene compound exhibit extremely high photosensitivity and, unlike the peroxide-based polymerization initiator, have no risk of explosive decomposition due to friction, impact, and the like. For this reason, when the electrodeposition coating solution is circulated through the pipeline for a long time using a pump, paint adhering to the pump rotation shaft, valve sliding parts, etc. rotates the pump, opens and closes the valve. This is advantageous because there is no danger of ignition or explosion due to friction or impact due to operation or the like.

Further, since the titanocene compound itself has a visible light polymerization initiating ability, even if the spectral sensitizer (B) is not used (even if it is omitted), a visible light-sensitive electrodeposition coating material having practical sensitivity can be obtained. Composition, but the spectral sensitizer (B)
When used together, the photosensitivity is further increased, and when the nitrogen-containing compound (D) is further added, the photosensitivity, resolution and the like can be further increased.

Preferable examples of the iron-allene complex include those represented by the following three types of general formulas (I), (II) and (III).

In the above formula, X represents BF ₄ , RF ₆ , ASF ₆ or SbF ₆ ,
₄₁ and R ₄₂ are each a linear or branched alkyl group having 1 to 6 carbon atoms, Preferred examples of the titanocene compound include those represented by the following general formula (IV).

Wherein the two R ₄₃ are each independently unsubstituted or 1 to
Represents cyclopentadienyl substituted with two methyl groups (preferably cyclopentadienyl or methylcyclopentadienyl), and R ₄₄ and R ₄₅ are each independently the following formula: [Wherein, R ₄₆ represents a fluorine atom, —CF ₃ or —CF ₂ CH ₃ , and R ₄₇ , R ₄₈ , R ₄₉ and R ₅₀ each independently represent a fluorine atom, —CF ₃ , —CH ₂ CH _{3 3,} a hydrogen atom, an alkyl group or an alkoxy group C ₁ -C _12] represents.

Specific examples of the titanocene compound include, for example, And the like.

The amount of these polymerization initiators is not critical,
It can be changed in a wide range depending on the type etc.,
Generally, it can be in the range of 0.1 to 25 parts by weight, preferably 0.2 to 10 parts by weight, per 100 parts by weight of the solid content of the photocurable resin (A). When used in a large amount exceeding 25 parts by weight, the stability of the resulting composition tends to decrease.

(D) Nitrogen-containing compound When the nitrogen-containing compounds represented by the above general formulas (1) to (6) are blended in the visible light-sensitive electrodeposition coating composition of the present invention, the sensitizing effect is greatly amplified. High sensitivity. At the same time, the resolving power of the image obtained by using this is also amplified.

It is not clear why the above-mentioned effect is exerted, but the nitrogen-containing compound (D) interacts with the spectral sensitizer (B) to change the excited state of the sensitizer, and this causes amplification of the photosensitivity of the composition. It is thought to have an effect. In addition, since these nitrogen-containing compounds (D) have a strong ability to form a chelate with metal ions such as copper, metal ions eluted during electrodeposition coating and ionic compounds such as carboxyl groups in the photocurable resin (A). In order to suppress the reaction with the radicals, it prevents the precipitation resin from becoming high molecular weight or cross-linked by metal ions, so that the alkali solubility of the unexposed part during image formation is maintained, and the solubility of the exposed part and the unexposed part is maintained. It is considered that the difference becomes large and the resolution is amplified as a result.

In such a nitrogen-containing compound (D), general formula (1)
As shown in, for example, And benzotriazoles.

As the compound represented by the general formula (2), for example, And the like.

Examples of the compound represented by the general formula (3) include: And the like.

Examples of the compound represented by the general formula (4) include: And the like.

Examples of the compound represented by the general formula (5) include: Can be mentioned.

In addition, as the one represented by the general formula (6), for example, Can be mentioned.

Among the above-mentioned nitrogen-containing compounds (D), those particularly preferred in the present invention are benzotriazoles represented by the aforementioned general formula (1).

The nitrogen-containing compound (D) can be used singly or in combination of two or more in the composition for electrodeposition coating of the present invention. 0.01 to 20 parts by weight for 100 parts by weight per minute,
Preferably it is in the range of 0.1 to 10 parts by weight.

(E) Other components The electrodeposition coating composition of the present invention may further comprise, if necessary, a polymerizable unsaturated group-containing resin, for example, an ethylenically unsaturated group, in addition to the photocurable resin (A). Polyester acrylate resin, polyurethane resin, epoxy resin, acrylic resin, etc. containing vinyl; vinyl monomer such as (meth)
Acrylic esters; oligomers, such as diethylene glycol di (meth) acrylate, are usually blended in a range of 100 parts by weight or less, preferably 50 parts by weight or less per 100 parts by weight of the solid content of the photocurable resin (A). It is also possible to appropriately adjust the performance of the formed coating film.

Preparation of Visible Light-Sensitive Electrodeposition Paint Composition The photosensitive electro-deposition paint composition of the present invention may be prepared, for example, by adding a water-dispersed or water-soluble product of the photocurable resin (A) to a spectral sensitizer (B ), Polymerization initiator (C), nitrogen-containing compound (D)
And other components (E).

Water-dispersion or water-solubilization of the photocurable resin (A) is to neutralize with an alkali (neutralizing agent) when an anionic group such as a carboxyl group is introduced into the resin (A). Thus, when a cationic group such as an amino group is introduced, the reaction is carried out by neutralization with an acid (neutralizing agent). Examples of the alkali neutralizer used in this case include alkanolamines such as monoethanolamine, diethanolamine and triethanolamine; alkylamines such as triethylamine, diethylamine, monoethylamine, diisopropylamine, trimethylamine and diisobutylamine; dimethyl Alkylalkanolamines such as aminoethanol; alicyclic amines such as cyclohexylamine; alkali metal hydroxides such as sodium hydroxide and sodium hydroxide; and ammonia. Further, as the acid neutralizer, for example, formic acid, acetic acid,
Monocarboxylic acids such as lactic acid and butyric acid are exemplified. These neutralizing agents can be used alone or in combination. The amount of the neutralizing agent used is generally 0.2 to 1.0 equivalent, preferably 0.3 to 0.8 equivalent, per 1 mol of the ionic group contained in the resin (A).

In order to further improve the fluidity of the resin component by solubilizing or dispersing in water, a hydrophilic solvent such as methanol, ethanol, isopropanol, n-butanol, t-butanol, or methoxy may be added to the photocurable resin (A) as required. Ethanol, ethoxyethanol, butoxyethanol, diethylene glycol, methyl ether, dioxane, tetrahydrofuran and the like can be added. The amount of the hydrophilic solvent used is generally the same as that of the resin (A).
Up to 300 parts by weight per 100 parts by weight of solid components, preferably 100
It can be up to parts by weight.

Further, in order to increase the amount of coating on the object, a hydrophobic solvent such as toluene,
Petroleum solvents such as xylene; ketones such as methyl ethyl ketone and methyl isobutyl ketone; esters such as ethyl acetate and butyl acetate; alcohols such as 2-ethylhexyl alcohol and benzyl alcohol can also be added. The compounding amount of these hydrophobic solvents can be generally up to 200 parts by weight, preferably 100 parts by weight or less per 100 parts by weight of the solid component of the resin (A).

In addition to the above objects, the above-mentioned solvent can be used as a solvent for dissolving the spectral sensitizer (B), the polymerization initiator (C) and the nitrogen-containing compound (D). If the spectral sensitizer (B), the polymerization initiator (C) and the nitrogen-containing compound (D) are difficult to dissolve in the neutralized resin solution, dissolve them in an appropriate hydrophilic solvent or hydrophobic solvent in advance. After that, it is desirable to mix with the resin (A). The solvent that can be used can be selected from those described above, and the amount used is sufficient to dissolve the spectral sensitizer (B), the polymerization initiator (C) and the nitrogen-containing compound (D). is there.

The composition for the electrodeposition coating composition can be prepared by a conventionally known method, and the resin (A), the spectral sensitizer (B), the polymerization initiator (C), It can be carried out by thoroughly mixing the nitrogen-containing compound (D) and other components (E) and adding water.

The composition thus prepared is diluted with water in the usual manner, for example, with a pH in the range of 4 to 9, a bath concentration (solids concentration) of 3 to 25% by weight, preferably 5 to 15% by weight. The electrodeposition paint (or the coating bath) within the range described above can be used.

Electrodeposition coating and image formation The electrodeposition coating prepared as described above can be applied to the surface of a conductor to be coated as follows. As the conductor, a conductive material such as metal, carbon, tin oxide or the like, or a material in which these are adhered to the surface of plastic or glass by lamination, plating or the like can be used.

The bath temperature is controlled between 15 and 40 ° C., preferably between 15 and 30 ° C., and the pH and bath temperature are controlled within the stated ranges. Then, the conductor to be coated is immersed in the electrodeposition coating bath controlled as described above as an anode when the electrodeposition coating is anionic or as a cathode when the coating is cationic, and a DC current of 5 to 200 V is applied. Turn on electricity. The energization time is suitably 30 seconds to 5 minutes, and the resulting film thickness is generally 0.5 to 50 μm, preferably 1 to 10
μm.

After the electrodeposition coating, the object to be coated is taken out of the electrodeposition bath and washed with water, and then moisture and the like contained in the electrodeposition coating film are dried and removed with hot air or the like.

At this time, if necessary, a cover coat layer can be provided on the electrodeposition coating film by a method known per se (see JP-A-63-60594).

The electrodeposition coating film formed on the conductor surface as described above is obtained by exposing the visible light-sensitive electrodeposition coating film to visible light according to an image, curing the exposed film, and removing the unexposed film by a development process. An image can be formed.

Light sources for exposure include ultra-high, high, medium and low pressure mercury lamps, chemical lamps, carbon arc lamps, xenon lamps, metal halide lamps, fluorescent lamps, tungsten lamps, and sunlight. Among them, various types of lasers, such as a visible light beam in which ultraviolet light is cut by an ultraviolet cut filter or an oscillation line in the visible light region, can be used.

In the development process, wash the unexposed area film on the coating film with an aqueous alkaline solution when the electrodeposition paint is anionic, or with an acid aqueous solution with a pH of 5 or less when the electrodeposition paint is cationic. It is performed by Alkaline aqueous solutions that can be neutralized with free carboxylic acids in the coating, such as caustic soda, sodium carbonate, caustic potash, and ammonia water, to give water solubility, and acid aqueous solutions that use acetic acid, quinic acid, etc. It is possible.

After the development, the coating film is washed with water and dried with hot air or the like, so that a desired image is formed on the conductor. In addition, after performing etching as necessary to remove the exposed conductor, the resist film may be removed to manufacture a printed circuit board.

The composition for electrodeposition coating of the present invention and the image forming method using the same can be used for a wide range of applications, such as photoresists, planographic and letterpress plate-making materials, offset printing PS plates, information recording materials, and relief image making materials. Is applicable.

[Effect of the Invention] By performing electrodeposition coating using the composition for electrodeposition coating composition of the present invention, a uniform and smooth visible light-sensitive coating film having an arbitrary thickness can be obtained. Since no advanced technique is required for forming the coating film, workability is greatly improved as compared with the conventional coating film forming method. In addition, a thin film that cannot be achieved with a liquid paint or a photosensitive film can be easily obtained only by setting the electrodeposition conditions, and the image obtained by exposure becomes sharper than conventional ones. effective. Furthermore, the composition for an electrodeposition coating composition of the present invention requires less use of an organic solvent than conventional liquid coating compositions or film-form compositions, so that it is less harmful to humans and less likely to fire. Further, the composition for electrodeposition coating of the present invention has a high sensitivity to visible lasers such as an algo-ion laser having an oscillation line at 488 nm,
There are advantages such as high-speed scanning exposure using such a laser.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. “Parts” and “%” indicate parts by weight and% by weight, respectively.

Photocurable resin synthesis agent 1 Methyl methacrylate 40 parts, butyl acrylate 40
Part of a mixed solution consisting of 20 parts of acrylic acid and 2 parts of azobisisobutyronitrile at 110 ° C. in a nitrogen gas atmosphere.
Was added dropwise over 90 hours to 90 parts of propylene glycol monomethyl ether (hydrophilic solvent) held in the flask. After dropping, the mixture was aged for 1 hour, and 1 part of azobisdimethyl valeronitrile and 10 parts of propylene glycol monomethyl ether were added.
Was added dropwise over 1 hour and aged for 5 hours to obtain a high acid value acrylic resin (155 oxide) solution. Next, glycidyl methacrylate 24 parts in this solution,
0.12 parts of hydroquinone and 0.6 parts of tetraethylammonium bromide are added, and the mixture is reacted at 110 ° C. for 5 hours while blowing air into the photocurable resin (acid value: about 50, degree of unsaturation: 1.
35 mol / kg, Tg point 20 ° C, number average molecular weight about 20,000) solution was obtained.

Synthesis example 2 of photocurable resin 60 parts of styrene, 10 parts of methyl acrylate, acrylic acid
A mixed solution composed of 30 parts and 3 parts of azobisisobutyronitrile was dropped into 90 parts of cellosolve kept at 120 ° C. in a nitrogen gas atmosphere over 3 hours. After the dropping, the mixture is aged for 1 hour, and a mixed solution composed of 1 part of azobisdimethylvaleronitrile and 10 parts of cellosolve is added dropwise for 1 hour, and the mixture is further aged for 5 hours to obtain a high acid value acrylic resin (acid value 233).
A solution was obtained. Next, 35 parts of glycidyl methacrylate, 0.13 part of hydroquinone and 0.6 part of tetraethylammonium bromide were added to this solution, and the mixture was reacted at 110 ° C. for 5 hours while blowing air thereinto, thereby causing a photocurable resin (acid value of about 70,
Unsaturation degree 1.83 mol / kg, Tg point 45 ° C, number average molecular weight about 15,00
0) A solution was obtained.

Synthesis Example 3 of Photocurable Resin 25 parts of methyl methacrylate, n-butyl acrylate
DMF1 in which a mixture of 15 parts, 15 parts of acrylic acid, 45 parts of 2-hydroxyethyl methacrylate and 2 parts of azobisisobutyronitrile was kept at 80 ° C. under a nitrogen gas atmosphere.
It was dropped into 00 parts over 3 hours. After dropping, aging for 1 hour, 1 part of azobisdimethylvaleronitrile and DMF
A mixture of 5 parts of (dimethylformamide) was added dropwise over 1 hour, and the mixture was aged for 5 hours to obtain a high acid value acrylic resin (acid value 115) solution.

To 200 parts of this polymerization solution, 120 ml of pyridine was added, and 57 parts of cinnamic acid chloride dissolved in 150 ml of DMF was added dropwise at 10 ° C. or lower, followed by stirring at 50 ° C. for 4 hours. The reaction solution was poured into 500 ml of methanol to precipitate the polymer, reprecipitated with THF (tetrahydrofuran) -water, further reprecipitated with THF-methanol, purified and dried at room temperature under reduced pressure. The resulting photocurable resin having a cinnamoyl group as a photosensitive group had an acid value of 81, a Tg point of 51 ° C., and a number average molecular weight of about 20,000. The amount of cinnamoyl groups was 3.69 mol / kg.

100 parts of this resin is propylene glycol methyl ether 5
A solution dissolved in a mixed solvent of 0 part and 50 parts of n-butanol was used.

Synthesis example 4 of photocurable resin 38 parts of methyl methacrylate, 38 parts of butyl acrylate
Part of a mixture of 24 parts of acrylic acid and 2 parts of azobisisobutyronitrile at 110 ° C. in a nitrogen gas atmosphere.
Was added dropwise over 90 hours to 90 parts of propylene glycol monomethyl ether (hydrophilic solvent) held in the flask. After dropping, the mixture was aged for 1 hour, and 1 part of azobisdimethyl valeronitrile and 10 parts of propylene glycol monomethyl ether were added.
Was added dropwise over 1 hour, and aged for 5 hours to obtain a high acid value acrylic resin (acid value 155) solution. Next, 30 parts of allyl glycidyl ether was added to this solution,
Add 0.12 parts of hydroquinone and 0.6 parts of tetraethylammonium bromide and blow in air at 110 ° C.
After reacting for hours, the photocurable resin (acid value about 54, degree of unsaturation 1.51
Mol / kg, Tg point 25 ° C., number average molecular weight about 18,000).

Synthesis Example 5 of Photocurable Resin Using 20 parts of methyl methacrylate, 60 parts of acrylic acid, 20 parts of methacrylic acid and 6 parts of t-butyl peroxyoctoate, polymerization was carried out at 110 ° C. in 90 parts of n-butyl alcohol. Later, glycidyl methacrylate 114
Part, hydroquinone 0.24 part and tetraethylammonium bromide 1.0 part, and reacted in the same manner as in Synthesis Example 1 to obtain a photocurable resin (acid value 70, degree of unsaturation 3.75 mol / kg, Tg
Point 8 ° C., number average molecular weight 18,000) solution was obtained.

Synthesis Example 6 of Photocurable Resin 30 parts of glycidyl methacrylate, 5 parts of styrene, n-
Butyl methacrylate 24 parts, methyl acrylate 23 parts,
A mixed solution consisting of 18 parts of dimethylaminoethyl methacrylate and 5 parts of azobisisovaleronitrile was dropped into 90 parts of cellosolve maintained at 80 ° C. in a nitrogen gas atmosphere over 3 hours. After the dropwise addition, the mixture was aged for 1 hour, and a mixed solution composed of 1 part of azobisdimethylvaleronitrile and 10 parts of cellosolve was added dropwise for 1 hour, and the mixture was aged for 5 hours to obtain an acrylic resin solution. Next, 15 parts of acrylic acid and 0.13 part of hydroquinone were added to this solution, and the mixture was reacted at 110 ° C. for 5 hours while blowing air into the photocurable resin (amine value 56, unsaturated equivalent 1.83 mol / kg, Tg 20 ° C., several times). An average molecular weight of about 15,000) was obtained.

Example 1 To 100 parts of the photocurable resin (solid content) obtained in Synthesis Example 1 was sufficiently neutralized by adding 6 parts of triethylamine, and then the spectral sensitizer A-1 was added to 10 parts of a solvent (benzyl alcohol). Was added and mixed well, and 7 parts of a radical generator (di-tert-butyldiperoxyisophthalate) was further added and mixed. Next, deionized water was added thereto to adjust the solid content concentration to 15%, and an electrodeposition coating bath (pH 6.5) was obtained.

Using this electrodeposition coating bath, a copper-clad laminate for printed wiring (40 × 150 × 0.8 mm) was used as an anode, and a DC current of 45 mA / cm ² was applied at a bath temperature of 25 ° C. for 3 minutes to perform electrodeposition coating. Got it. The obtained electrodeposited film was washed with water and dried at 80 ° C. for 5 minutes to obtain a 12 μm-thick non-tacky smooth photosensitive film. The photosensitive film was irradiated with light using a spectral irradiation apparatus (a diffraction grating spectroscope manufactured by Narumi Shokai Co., Ltd.), and then developed with a 1% aqueous solution of sodium carbonate at 30 ° C. for 1 minute to form an image. . The photosensitive film was exposed using the above-mentioned spectral irradiation apparatus, developed with a 1% aqueous solution of sodium carbonate at 30 ° C. for 1 minute, washed with water, and then subjected to a wavelength of 488 nm
The sensitivity was defined as the minimum exposure energy at which the cured film could remain at m, and is shown in Table 1 below.

Examples 2 to 24 An electrodeposition coating bath was prepared and images were formed in the same manner as in Example 1 except that the photocurable resin, the spectral sensitizer, the polymerization initiator and the nitrogen-containing compound shown in Table 1 were used. Table 1 below shows the sensitivity.
Shown in

Example 25 100 parts (solid content) of the photocurable resin obtained in Synthesis Example 7 was treated with acetic acid.
After neutralization with 3.6 parts, 1 part of photosensitizer A-1 and 3,3 ′,
A solution prepared by dissolving 5 parts of 4,4'-tetra (t-butylpaoxycarbonyl) benzophenone in 10 parts of benzyl alcohol is added and mixed, and then deionized water is added to adjust the solid content to 15%. An electrodeposition coating bath (pH 6.4) was used.

Using this electrodeposition bath, a copper-clad laminate (40 × 150 × 0.8 mm) for printed wiring was used as a cathode, and a bath temperature of 25 ° C. and 45 mA / cm ₂
Was applied for 3 minutes to perform electrodeposition coating. The obtained electrodeposited film was washed with water and dried at 80 ° C. for 5 minutes to obtain a 12 μm-thick non-tacky smooth photosensitive film. The photosensitive film is irradiated with light using a spectral irradiator (diffraction grating spectrometer manufactured by Narumi Shokai Co., Ltd.), and then irradiated with a 2% lactic acid aqueous solution at 30 ° C.
An image was formed by developing for minutes. The photosensitive film was exposed using the above-mentioned spectral irradiation apparatus, and was exposed to a 2% aqueous lactic acid solution at 30 ° C. for 1 hour.
After developing for 1 minute and washing with water, the minimum exposure energy at which a cured film can remain at a wavelength of 488 nm is defined as sensitivity and is shown in Table 1 below.

Examples 26 to 30 An electrodeposition coating bath was prepared and images were formed in the same manner as in Example 25 except that the polymerization initiator and the nitrogen-containing compound shown in Table 1 were used. The sensitivity is shown in Table 1 below.

Abbreviations or structures in Table 1 are as follows.

Polymerization initiator: PBIF: ditertiary butyl diperoxyisophthalate AZV: 2,2 'azobis (2,4-dimethylvaleronitrile) MK: Michler's ketone BP: benzophenone DIB: diphenyl iodonium bromide DETX: 2,4-diethyl Thioxanthone BTTB: 3,3 ', 4,4'-tetra (tert-butylperoxycarbonyl) benzophenone CHPK: 1-hydroxycyclohexylphenyl ketone Next, the resolving power when an image was formed was examined for several types of the examples. The resolving power was evaluated in terms of pattern formability by direct writing using a high precision laser direct writing apparatus NIKON LP-3000D manufactured by Nikon Corporation. Patternability is represented by the finest lines / spaces that can be formed by removing the exposed conductor portions with an acid or alkali etch after development. The results are shown in Table 2 below.

Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI // C09D 133/00 C09D 133/00 (72) Inventor Takao Yamamoto 4-7-1, Higashi-Hachiman, Hiratsuka-shi, Kanagawa Kansai Paint Co., Ltd. (72 ) Inventor Kenji Seko 4-171-1, Higashi-Hachiman, Hiratsuka-shi, Kanagawa Prefecture Inside Kansai Paint Co., Ltd. (72) Inventor Hiroshi Yoshikawa 4-171-1, Higashi-Hachiman, Hiratsuka-shi, Kanagawa Kansai Paint Co., Ltd. Naozumi 4-17-1, Higashi-Hachiman, Hiratsuka-shi, Kanagawa Prefecture Kansai Paint Co., Ltd. (58) Field surveyed (Int. Cl. ⁶ , DB name) C09D 5/44

Claims (3)

(57) [Claims] (A) a photocurable resin containing a photosensitive group and an ionic group which can be crosslinked or polymerized by irradiation with light; (B) the resin (A) which is excited by absorbing visible light and A visible light-sensitive electrodeposition coating composition, comprising: a spectral sensitizer having an interactive property with water; and (C) a water-insoluble polymerization initiator. (A) a photocurable resin containing a photosensitive group and an ionic group which can be crosslinked or polymerized by light irradiation; (B) the resin (A) which is excited by absorbing visible light and (C) a water-insoluble polymerization initiator, and (D) the following general formulas (1) to (6): In the formula, X represents a hydrogen atom or a hydroxyl group; R ₁ , R ₂ and R ₃ each represent a hydrogen atom, a chlorine atom or an alkyl group having 1 to 6 carbon atoms; In the formula, R ₄ and R ₅ are each a hydrogen atom or a carbon number of 1-6.
Represents an alkyl group of In the formula, R ₆ , R ₇ and R ₈ each represent a hydrogen atom, a hydroxyl group or an alkyl group having 1 to 12 carbon atoms; In the formula, R ₉ , R ₁₀ and R ₁₁ each represent a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms, In the formula, R ₁₂ represents a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms, In the formula, R ₁₃ and R ₁₄ each represent a hydrogen atom or a carbon number 1 to
A composition for a visible light-sensitive electrodeposition coating composition comprising at least one nitrogen-containing compound selected from the group consisting of 12 alkyl groups and n is an integer of 1 to 3. (I) Electrodepositing the visible light-sensitive electrodeposition coating composition according to claim 1 or 2 on a conductor surface, and (ii) applying visible light to the obtained electrodeposition coating film. An image forming method comprising: exposing by partially irradiating; and (iii) removing an unexposed portion by contacting with a developing solution.