JP3111708B2 - Photopolymerizable composition and photopolymerizable element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photopolymerizable composition used for manufacturing a printed wiring board, and more particularly to a photopolymerizable element used in a technique called a tenting method.

[0002]

2. Description of the Related Art Increasing the polymerization rate of a photopolymerizable composition, that is, increasing the photosensitivity of the photopolymerizable composition, is advantageous in that the exposure time of active light can be shortened. Various methods have been used. For example,
In order to increase photosensitivity, a method of adding a photoinitiator or a sensitizer to a photopolymerizable composition containing an ethylenically unsaturated group-containing compound has been performed.

[0003] These photoinitiators or sensitizers include 2
Polynuclear quinones such as -ethylanthraquinone and 2-tert-butylanthraquinone; aromatic ketones such as benzophenone and 4,4'-bis (dimethylamino) benzophenone;
Benzoin derivatives such as benzoin methyl ether have been used. However, even if these photoinitiators or sensitizers are used, the photosensitivity of the conventional photopolymerizable composition obtained is not always sufficient.

Japanese Patent Publication No. 53-27605 discloses an acridine or phenazine compound capable of containing a condensed benzene ring, particularly as a photoinitiator having high sensitivity and excellent storage stability in the presence of oxygen. JP-A-59-226002 discloses a combination of 9-phenylacridine and a thiol group-containing compound as a highly sensitive photoinitiator.
No. 164,739 discloses substituted 9-benzoyl acridines as highly sensitive photoinitiators. However, even when these compounds were used, a photopolymerizable composition having satisfactory photosensitivity was not obtained.

In the production of printed wiring boards, the tenting method requires simultaneous exposure of both sides of a through-hole substrate. However, in some cases, only one side is exposed and copper in the through-hole is removed by etching. A technique is performed. At this time, since the photopolymerizable element transmits the exposure light beam, when exposed from both sides, the photopolymerizable elements on the opposite sides are also exposed, causing a photochemical reaction to the part not desired to be exposed, and as a result, back fogging Occurs, and copper remains during etching.

As a method for solving this problem, it is known that a thioxanthone compound-based sensitizer is used alone in an amount of 1.5 or more as the absorbance of ultraviolet ray ABS. After the resist shape becomes inverted trapezoid,
Adhesion after etching deteriorates. On the other hand, if the amount is too small, sufficient photosensitivity cannot be obtained.

[0007]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned drawbacks of the prior art, increases photosensitivity, is excellent in adhesion and resolution, and is excellent in back fogging. It is to provide a photopolymerizable element used.

[0008]

According to the present invention, there is provided a compound comprising a specific bisacridine compound, a specific aminophenyl ketone, and a specific thioxanthone compound as a photoinitiator. The object has been achieved by adding the composition to the composition.

That is, the present invention provides (a) at least one
20 to 60 parts by weight of a compound having two ethylenically unsaturated groups, (b) 40 to 80 parts by weight of a thermoplastic organic polymer [(a)
And the total amount of (b) is 100 parts by weight], (c) the general formula (I)

Embedded image Wherein R ₁ represents an alkylene group having 6 to 12 carbon atoms, and 0.01 to 3 parts by weight based on 100 parts by weight of the total of (a) and (b). parts and (d) one general formula (III)

Embedded image [Wherein R ₆ and R ₇ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms], and the total amount of the above (a) and (b) is 100% by weight. Parts to 0.01 parts by weight of the photopolymerizable composition and the composition coated on a support, and dried to a film thickness of 20 to 10 parts by weight.
The present invention relates to a photopolymerizable element having a 0 μm layer.

Hereinafter, the present invention will be described in more detail. As the compound containing at least one ethylenically unsaturated group used as the component (a) in the photopolymerizable composition of the present invention, for example, a polyhydric alcohol to which an α, β-unsaturated carboxylic acid is added The resulting compound, for example, tetraethylene glycol di (meth) acrylate [(meth) acrylate means methacrylate or acrylate. The same applies hereinafter), polyethylene glycol di (meth) acrylate (having 2 to 14 ethylene groups), trimethylolpropane di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate,
Pentaerythritol tetra (meth) acrylate, polypropylene glycol di (meth) acrylate (having 2 to 14 propylene groups), dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, etc .; containing a glycidyl group Compounds obtained by adding an α, β-unsaturated carboxylic acid to a compound, such as trimethylolpropane triglycidyl ether triacrylate, bisphenol A diglycidyl ether diacrylate and the like; polyhydric carboxylic acids such as phthalic anhydride and the like Substance having a hydroxyl group and an ethylenically unsaturated group, for example, β-hydroxyethyl (meth)
Esterified product with acrylate or the like; alkyl ester of acrylic acid or methacrylic acid, for example, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate Esters and the like. Further, component (a) used in the photopolymerizable composition of the present invention.
As a compound having at least one isocyanate group, for example, toluene diisocyanate, trimethylhexamethylene diisocyanate, diphenyl diisocyanate, diphenylmethane diisocyanate, 3,
And 3'-dimethyl-4,4'-diphenyl diisocyanate, a compound having at least one hydroxyl group and at least one ethylenically unsaturated group, for example, beta-hydroxyethyl (meth) acrylate, preparative trimethylolpropane di (meth A) acrylate, pentaerythritol tri (meth) acrylate, diethylene glycol mono (meth) acrylate, and the like.

From the viewpoints of odor and safety, the boiling point of the component (a) is preferably 100 ° C. or higher at normal pressure.

The amount of the component (a) is from 20 to 60.
Parts by weight. When the amount is less than 20 parts by weight, the photosensitivity is reduced. When the amount is more than 60 parts by weight, the photocured product is apt to be brittle, and when used as a photosensitive film, the coating properties are poor.

The thermoplastic organic polymer as the component (b) in the photopolymerizable composition of the present invention includes, for example, a copolymer of an alkyl (meth) acrylate and (meth) acrylic acid, Copolymers of alkyl acrylate, (meth) acrylic acid, and a vinyl monomer copolymerizable therewith are used. Examples of the alkyl (meth) acrylate include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate.
Examples of the vinyl monomer copolymerizable with the alkyl (meth) acrylate or the (meth) acrylic acid include tetrahydrofurfuryl (meth) acrylate, ethylene glycol di (meth) acrylate, and (meth) acrylic acid. Glycidyl ester, 2,2
2-trifluoroethyl (meth) acrylate, 2,
Examples thereof include 2,3,3-tetrafluoropropyl (meth) acrylate, acrylamide, diacetone acrylamide, styrene, and vinyl toluene.

As the thermoplastic organic polymer, homopolymers of the above compounds can also be used. Further, copolyesters such as polyesters of terephthalic acid, isophthalic acid, and sebacic acid, and the like, and butadiene and acrylonitrile can be used. Copolymers, cellulose acetate, cellulose acetate butyrate, methyl cellulose, ethyl cellulose and the like can also be used.

The blending amount of the thermoplastic organic polymer as the component (b) is determined so as to be 40 to 80 parts by weight, and the total amount with the component (a) is 100 parts by weight. The use of the thermoplastic organic polymer can improve the coating properties and the film strength of the obtained cured product. When the amount is less than 40 parts by weight, the photocured product is apt to be brittle, and when used as a photosensitive film, the coating properties are poor. Also, 80
When the amount is more than the weight part, the other components become relatively small and the light sensitivity is lowered.

The weight average molecular weight of the thermoplastic organic polymer is from 10,000 to 100
0000 is preferable, and 10,000 to 150,000
Is more preferable. In the present specification, the weight average molecular weight is a value measured by gel permeation chromatography and converted using a calibration curve of standard polystyrene.

In the photopolymerizable composition of the present invention, the components (c) and (d) are used as a photoinitiator. The component (c) is an acridine compound represented by the general formula (I), and specifically, for example, 1,2-bis (9-acridinyl) ethane, 1,3-bis (9-acridinyl) propane 1,4-bis (9-acridinyl) butane, 1,
6-bis (9-acridinyl) hexane, 1,7-bis (9-acridinyl) heptane, 1,8-bis (9-acridinyl) octane, 1,9-bis (9-acridinyl) nonane, 1,10- Bis (9-acridinyl) decane, 1,11-bis (9-acridinyl) undecane,
1,12-bis (9-acridinyl) dodecane, 1,1
4-bis (9-acridinyl) tetradecane, 1,16
-Bis (9-acridinyl) hexadecane, 1,18-
Bis (9-acridinyl) octadecane, 1,20-bis (9-acridinyl) eicosane, 1,3-bis (9
-Acridinyl) -2-oxapropane, 1,3-bis (9-acridinyl) -2-thiapropane, 1,5-bis (9-acridinyl) -3-thiapentane and the like. Alkylene group linking acridine rings (R ₁ in general formula (I))
A compound having 6 to 12 carbon atoms is preferred from the viewpoint of photosensitivity and the like.

The acridine compound represented by the general formula (I) can be easily produced, for example, by reacting diphenylamine with a divalent carboxylic acid in the presence of a metal chloride.

In the photopolymerizable composition of the present invention, the compounding amount of the component (c) is 100% in total of the components (a) and (b).
0.01 to 3 parts by weight with respect to parts by weight. 0.01
If the amount is less than 10 parts by weight, sufficient photosensitivity cannot be obtained, so that the progress of photopolymerization is insufficient.
The storage stability of the photopolymerizable composition is reduced, and the composition is not practical.

The component (d) used as a photoinitiator in the present invention is an aminophenyl ketone compound represented by the general formula (II) and / or a thioxanthone compound represented by the general formula (III). Here, examples of the compound represented by the general formula (II) include p, p-dimethylaminobenzophenone, p, p-diethylaminobenzophenone, p, p-dipropylaminobenzophenone and the like. Examples of the thioxanthone compound represented by the general formula (III) include 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, and 2-methyl-4
-Ethylthioxanthone, 2,4-dipropylthioxanthone, 2-propyl-4-ethylquinoxantone and the like.

The aminophenyl ketone compound represented by the general formula (II) has a total amount of the components (a) and (b) of 100
0.01 to 3.0 parts by weight with respect to parts by weight,
It is preferable to use 3 to 0.2 parts by weight. If this amount is less than 0.01 part by weight, sufficient photosensitivity and resolution cannot be obtained. If it exceeds 3.0 parts by weight, light absorption on the surface of the composition during exposure increases, and Light curing becomes insufficient.

The thioxanthone compound represented by the general formula (III) has a total amount of the component (a) and the component (b) of 1
With respect to 00 parts by weight, 0.01 to 3.0 parts by weight is used,
It is preferable to use 0.03 to 0.5 parts by weight. If this amount is less than 0.01 part by weight, sufficient photosensitivity and back fogging property cannot be obtained, and if it exceeds 3.0 parts by weight, the adhesion will be reduced.

The photoinitiator as component (d) in the present invention, when they contain both users of thioxanthone compound represented by the general formula (II) aminophenyl ketone compound represented by and the general formula (III) , The total amount of
With respect to 100 parts by weight of the total of the components (a) and (b),
It is blended so as to be 0.01 to 3.0 parts by weight.

Further, the photopolymerizable composition of the present invention may contain a coloring agent such as a dye or a pigment. As the coloring agent, for example, fuchsin, auramine base, crystal violet, Victoria Pure Blue, malachite green, methyl orange, acid violet RRH and the like are used.

Further, known additives such as a plasticizer, an adhesion promoter and talc can be added to the photopolymerizable composition of the present invention. And a combination of a halogen compound and a leuco dye.

In the photopolymerizable composition of the present invention, the above-mentioned components are, for example, acetone, methyl ethyl ketone, methyl isobutyl ketone, methyl cellosolve, ethyl cellosolve, chloroform, methylene chloride, methyl alcohol,
By dissolving, mixing or dispersing in ethyl alcohol, aqueous ammonia, water, or the like, a solution or aqueous solution of the photopolymerizable composition is obtained, or the component (a) is used without using such a solvent or dispersion solvent. Can be used as a solvent-free solution-type photopolymerizable composition in which another component is dissolved in a compound containing an ethylenically unsaturated group.

These can be directly applied to a base material such as a copper plate, an aluminum plate, a ceramic plate, a plastic plate or the like by a known means such as roll printing, curtain coating, spray coating, screen printing, etc., immersion, electrodeposition and the like. It may be applied, or once applied to a support such as a polyester film, and when a solvent or a dispersion solvent is contained, these are removed by drying to form a photopolymerizable composition layer on the support. If necessary, a photopolymerizable element in which a polyolefin film such as polyethylene is laminated as a protective film on the layer to form a photopolymerizable element may be applied to a substrate, and the method is not particularly limited.

The photopolymerizable composition of the present invention comprises a photocurable paint, a photocurable ink, a photosensitive printing plate, a photoresist,
It can be used for various uses such as dry film and electrodeposition photoresist, and there is no particular limitation on the use. For example, when used as a printed wiring board photoresist, the solution-type photopolymerizable composition is applied to a base material such as a copper plate, and when containing a liquid material, dried, exposed to active light, and photocured. Can be used. Further, the solution-type photopolymerizable composition can be applied on a polyethylene terephthalate film, dried when a solvent is contained, laminated on a substrate, and cured by light. The light source of the active light used for photo-curing has a wavelength of 300
A material that emits light of up to 450 nm is used, and a mercury vapor arc, a carbon arc, a xenon arc, or the like is used.

[0029]

EXAMPLES The present invention will be described in more detail with reference to the following examples, but the present invention is not limited by the following examples.

Example 1 Methyl methacrylate / methacrylic acid / 2-ethylhexyl methacrylate (weight ratio: 60/20/20) copolymer (weight average molecular weight: 80,000) 52 g, tetraethylene glycol diacrylate 10 g, polyoxyethylation (polymerization) Degree 5) Bisphenol A dimethacrylate (BPE-10, manufactured by Shin-Nakamura Chemical Co., Ltd.) 30
g, malachite green 0.2 g, hydroquinone 0.
1 g, leuco crystal violet 1.0 g, carbon tetrabromide 0.5 g, toluene 10 g, methyl cellosolve 13
0 g, methyl alcohol 5 g and chloroform 10 g, and a solution containing 93.3 g of non-volatile components (hereinafter referred to as solution A)
248.8 g).

The photoinitiator shown in Table 1 was dissolved in the solution A to obtain a solution of the photopolymerizable composition.

Next, the solution of the photopolymerizable composition was added to 25
The composition was uniformly coated on a polyethylene terephthalate film having a thickness of μm, and dried with a hot air convection dryer at 100 ° C. for 5 minutes to obtain a photopolymerizable element. The thickness of the photopolymerizable composition layer after drying was 25 μm.

On the other hand, the copper surface of a copper-clad laminate (manufactured by Hitachi Chemical Co., Ltd., trade name: MCL-E-61) which is a glass epoxy material in which a copper foil having a thickness of 35 μm is laminated on both sides is # 8.
It was polished with a sandpaper of No. 00, washed with water and dried in an air stream.

The obtained copper clad laminate was heated to 60 ° C.
The photopolymerizable element was laminated on the copper surface while being heated to 120 ° C.

Using a negative film on the substrate thus obtained, a 3 kW high-pressure mercury lamp (Oak Manufacturing Co., Ltd.)
Manufactured by Phoenix-3000)
Exposure was performed so that the number of remaining step steps of the step tablet was 8.0. At this time, in order to evaluate the light sensitivity, a negative film (optical density 0.05 was set as the first step, and the optical density was set to 0.15 for each step) so that the light transmission amount was reduced stepwise. Increasing step tablets) were used.

After exposure, the polyethylene terephthalate film was removed, and a 1% by weight aqueous solution of sodium carbonate was added at 30 ° C.
For 50 seconds to remove unexposed portions.

Table 1 shows the exposure amount at which the number of remaining steps is 8.0, and the adhesion and resolution at that time. Table 1 also shows the back fogging property that occurs during simultaneous double-sided exposure on the through-hole substrate.

[0038]

[Table 1]

[0039]

The photopolymerizable composition of the present invention and the photopolymerizable element using the same have high sensitivity, high adhesion and high resolution, and do not cause back fogging. Therefore, the photopolymerizable composition of the present invention and the photopolymerizable element using the same can be used in various applications to obtain good results, for example, contributing to higher density of a printed wiring board. it can.

Continuation of the front page (72) Inventor Hajime Kadomaru 4-3-1-1, Higashicho, Hitachi City, Ibaraki Pref. Hitachi Chemical Co., Ltd. Yamazaki Factory (56) References JP-A-4-136942 (JP, A) JP-A Heisei JP-A-2-294302 (JP, A) JP-A-4-301644 (JP, A) JP-A-2-289602 (JP, A) JP-A-2-54269 (JP, A) JP-A-5-53317 (JP, A A) JP-A-5-249658 (JP, A) JP-A-5-22413 (JP, A) JP-A-6-35190 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) ) G03F 7/00-7/42

Claims (3)

(57) [Claims] (1) 20 to 60 parts by weight of a compound having at least one ethylenically unsaturated group, (b) 40 to 80 parts by weight of a thermoplastic organic polymer [(a)
So that the total amount of (b) and (b) is 100 parts by weight], (c) the general formula (I) Wherein R ₁ represents an alkylene group having 6 to 12 carbon atoms, and 0.01 to 3 parts by weight based on 100 parts by weight of the total of (a) and (b). parts and (d) one general formula (III) ## STR2 ## [Wherein R ₆ and R ₇ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms], and the total amount of the above (a) and (b) is 100% by weight. A photopolymerizable composition containing 0.01 to 3 parts by weight based on parts. 2. The compound of the general formula (II) as component (d) : [Wherein R ₂ , R ₃ , R ₄ and R ₅ are each independently hydrogen
Represents an alkyl group having 1 to 3 carbon atoms or atoms)
2. The photopolymerizable composition according to claim 1, further comprising a photoinitiator.
Adult. 3. A process according to claim 1 or 2 photopolymerizable composition according coated on a support, a photopolymerizable element comprising a layer of dry film thickness after 20 to 100 [mu] m.