JPS61183644A - Ultraviolet-curing resin composition capable of forming colored image - Google Patents

Abstract

PURPOSE:To increase the color developability and to cure rapidly a colored image by using a polymer for filling, a radical-polymerizable monomer having an unsatd. double bond, a system consisting of an ultraviolet-polymn. initiator and a sensitizer, and the colorless leuco body of a dye as principal components. CONSTITUTION:An ultraviolet-curing resin composition capable of forming the colored image is prepd. by using the polymer (A) for filling, the radical- polymerizable monomer (B) having the unsatd. double bond and/or a radical- polymerizable oligomer having unsatd. double bonds, a system (C) consisting of an ultraviolet-polymn. initiator and the sensitizer, and the colorless leuco body of a dye (D) as principal components. A dye may be further used. In the resin composition, free radicals are generated in the system (C) by ultraviolet rays to initiate and accelerate the photopolymn. reaction of the monomer (B). A compound represented by the formula (where each of X1 and X2 is Br, Br2, Cl or Cl2) or the mixture of such compounds is added to the resin composition as a component which makes the leuco body (D) develop color by oxidation.

Description

Detailed Description of the Invention [Technical Field] The present invention relates to ultraviolet rays capable of forming colored images, which are used as a photosensitive layer in 7t) resist dry films used in forming wiring patterns on printed wiring boards, solder masks, etc. The present invention relates to a curable resin composition.

[Background technology]

When forming a wiring pattern on a printed wiring board or when forming a dark mask, etc., the resist ink is printed on the printed wiring board board in the same shape as the required pattern by silk screen printing, etc., and then heated. This is done using a method of curing and applying a resist, and a photoresist method. In the photoresist method, liquid photoresist, which is a liquid photosensitive liquid, is applied to the entire surface of the printed wiring board, dried,
Next, the method of forming a pattern resist using a photographic method has traditionally been the mainstream, but these methods have problems with workability and safety, so recently a method using a photoresist film has been used. However, it has attracted attention because of its excellent workability and safety, as well as its excellent pattern resolution and fewer defects due to missing lines, binho/L/, etc., and its range of use is expanding.

However, in order to further improve the reliability of electronic equipment,
There is a desire to further improve the reliability of printed wiring boards, and in particular, it is desired that the defective delivery rate of industrial printed wiring boards be below 1100 pp (0.01%). For this reason, even if a pattern is formed using a dry film, the current situation is that all printed wiring boards are inspected before being shipped.

On the other hand, in the manufacturing process of printed wiring boards, the process is becoming automated and continuous, and examples of the negative effects of this include dust and scratches that adhere to silk screen masks and photoresist masks. It is conceivable that defective resist patterns may be formed in succession, resulting in the production of defective printed wiring boards in succession.

In order to eliminate such adverse effects, it is necessary to conduct at least a visual inspection when supplying the material to the resist pattern hardening device in the case of the silk screen method, and at the time of supplying it to the developing device in the case of the photoresist method. There is.

In the case of the photoresist method, when it is supplied to the developing machine, it is not only impossible to visually determine whether the pattern is good or bad after mask exposure, but also the layers before exposure can be distinguished, leading to such quality control problems. In order to solve this problem, efforts have been made to develop, change color, or fade color by exposure to ultraviolet rays. For example, Tokuko Shosen-17986, Tokuko Sho45-4
011i0, Tokko Sho (7-1896, Tokko Sho 48-3
2363, Special Publication No. 49-15490, Special Publication No. 50-2
There are 1089 etc.

However, such coloring materials may have a foul odor such as iodoform, be extremely expensive, or be difficult to obtain, or even if available, cannot be visually inspected under a yellow safety light. It's too much to do
At present, no definitive composition has been found that requires mixing.

[Purpose of the invention]

The present invention has been made in view of the above points, and an object of the present invention is to provide an ultraviolet curable resin composition capable of forming a colored image, which has excellent coloring properties and can be rapidly cured by adding a small amount. That is.・ [Disclosure of the Invention] Therefore, the present invention provides the following features: Polymer for filling 181 Radical polymerizable polymer and/or oligomer having unsaturated double bond 1C+ Thread of ultraviolet polymerization initiator and sensitizer ρ) Originally colorless Dye leuco body 0LAllBllCllDlt-4fill L, I
In the cI(7) system, free radicals are generated by ultraviolet rays, and IB
Formula [1] [However, Xl e Xl is "*"! *C1!
* This is an ultraviolet curable resin composition capable of forming a colored image, which is characterized by containing a compound consisting of an atom (representing a group) selected from Cgt or a mixture thereof.

The present invention will be explained in detail below.

When using the ultraviolet curable resin composition capable of forming a colored image according to the present invention to form a photosensitive layer for a photoresist film, either a solvent development stripping type or an alkaline aqueous solution development stripping type can be used. However, an alkaline aqueous solution development and peeling type that does not use an i-solvent is preferable in order to meet the needs of users in the future.

The ultraviolet curable resin composition includes a KiAJ-filled polymer, (B) a photopolymerizable monomer and/or oligomer, as is known in the art.
It is prepared by blending an IcI photopolymerization initiator, an accelerator system, ρ) an essentially colorless leuco dye and a dye system, 2) a thermal polymerization inhibitor, 2) other additives, and a C solvent.

First, as a filler polymer, polymers with reactive groups (for example, JP-B No. 43-26869, JP-B No. 5-M
No. 37316, etc.) may be used.

Polymethyl methacrylate is a typical example of the acrylic μ-based compound polymer, but in order to make it possible to develop with alkali by alkali dissolution to swelling, methyl methacrylate and methacrylate/%/l! It is preferable to use copolymers such as those described in US Pat. No. 2,893,868 and US Pat. No. 3,458,311, such as the copolymer of No. 2. Further, as the half-esterified product of a copolymer of vinyltoluene, itaconic acid, and maleic acid, those described in Japanese Patent Publication No. 55-38961, Japanese Patent Application Laid-Open No. 57-2035, etc. can be used. In order to make them soluble in alkaline water to swellable, -COOH group, -5O38 group, -NH
It is also possible to polymerize the superimposed polymer to a wide or even degree of addition (as disclosed in Japanese Patent Publication No. 50-15033 and Japanese Patent Publication No. Sho E1).
Of course, a small amount of alkali-insoluble polymers can also be mixed and used.

Other polyvinyl alcohol-based polymers, preferably water-soluble acetalized saponified products, may also be used.

Polyisocyanate-based polymers, unsaturated polyester-based, diallyl phthalate-based, soluble nylon-based, EBOKI V
Prepolymers and/or polymers may also be used, such as systems.

As the photopolymerizable physical polymerizable polymer and/or oligomer of tBl, monofunctional and/or polyfunctional acrylic ester μ-based materials having unsaturated double bonds are used. In order to make it soluble in alkaline water to swellable type, -COO
H group, -5o! H group, -NH! If a part or all of the material contains a group, etc., it will be harmful, but if it is made too hydrophilic, the cured film will be attacked by the action of the developer, coating agent, tinkering solution, electroless plating solution, etc. Since there is a risk of causing a so-called halo phenomenon defect, it is necessary to select an appropriate material in consideration of the above-mentioned filling polymer. For example, trimethylo-μpropane tri(meth)
Polymerizable polymers such as acrylates described in Japanese Patent Publication No. 53-40537, Japanese Unexamined Patent Application Publication No. 8417-8417, Japanese Patent Publication No. 31062-1988, etc. can be used. Monofunctional monomers such as dimethyaminoethyl methacrylate, acrylic acid, methyl methacrylate, 2-
Ethylhexy A/(meth)acrylate and the like can also be used, but these mainly act as a plasticizer, diluent, coloring system stabilizer, adhesive, and pH adjuster.

As the IcI ultraviolet polymerization initiator system, the formula (
In addition to the compound of 1) or a mixture thereof, benzophenone, 4.
4'-diethylaminobenzophenone, Mihitsu's ketone, benzo A/Zomethi μ keter p, benzoin isopropyl μ ether, thioxanthone, 2-isopropylthioxanthone, 1-hydroxy-1%! Dimethylacetophenone, 4-! /Mesen〃aminoech〃benzony)
, 2.2-jethoxyacetophenone, hydroxycyclohexylphenyl ketone, N,N-dimethylaminobenzoic acid isoamyl, benzoin ethyl ether, penzoin isobutylede, 0-pensy methyl μbenzoate, N-isopropyl Power bonyl compounds such as morpholinomethylthiophenone.

O-phenonethrillone, 2-mercaptobenzothiazo-
μ, 2-mercaptobenzimidazo-p.

2-Benzoxacylthio-μ, 2-mercapto-6-
Nitropenzothiazole〃, 2-Mercapto-4-pheniμ thiazo-〃, 6-amino-2-mercaptobenzothiazo-~, 2-mercapto-4-pheni~thiazole, Feniμ disulfide , Tetofumechi〃Chiokuhumjisa/
L/7 eyed, mercaptobenzoic acid, benzoxacy
, oxazo-μ, imidazole, 2-quinoline, 4-pyridine, poxypenzotriazole, quinaldine, and other nitrogen-containing heterocyclic compounds, and organic sulfur compounds. Peroxides such as benzoyl peroxide and G-t-guchi μ peroxide. Redox compound of ferrous ion and hydrogen peroxide, α, l
- azo and diazo compounds such as azobisisobutyronitri/I/, iodoform, ααα-triglomomethylphenysulfone, golomotrichloromethane, trichloroacetamide, ααα-trichlorotoluene, ααα-tribromoacetophenone, ωωω-Tribromuquinaldine, 2-(0-chlorophenyl)-4,5-dimethoxyphenylimidazolyN dimer, etc., Japanese Patent Publication No. 49-21601
The halogen compounds described in et al., photoreducible dyes such as rose bengal, etc. can be used.

These ultraviolet initiator and accelerator threads can be used in combination of two or more types.

As combinations of multi-component systems, there are Japanese Patent Publications Sho-19284, Tokko Sho-44-6361, and Tokko Sho-1 200.
Publication No. 67, Special Publication No. 48-38403, Special Publication No. 5
3-37902, Japanese Patent Publication No. 53-43988, Japanese Patent Publication No. 53-43989, Japanese Patent Publication No. 59-818
Publication No. 1283, Japanese Unexamined Patent Publication No. 54-13
0693, JP 53-37211, JP 55-60942, JP 58-171406
This can be done by following the instructions in the publication.

As the dye system (ρ), a color-forming compound such as a leuco dye is used. A mixed system of a dye and a color-forming compound can also be used. In this case, JP-A-51-73432
As shown in Japanese Patent Laid-Open No. 56-75642, a colored visible positive image having a mixed tone of a dye and a coloring material is obtained by exposure.

Of course, it is not necessary to contain a dye, but in this case, it is desirable to use a colored and transparent support film as suggested in Japanese Patent Publication No. 59-28345. Further, the coloring agent for coloring the coloring compound, including the compound of formula [1] according to the present invention, should be included in the above-mentioned Ic), and consideration should be given to the curing rate, etc.

As a thermal polymerization inhibitor, the inhibitor mixed in commercially available polymerization monomers alone is insufficient and often requires additional mixing. p-t-butyμ catechol 1'
, P-methoxyphenol, P-benzoquinone, anthofquinone, and other thermal polymerization inhibitors described in Japanese Patent Publication No. 55-38961 can be used. In particular, when used as a photoresist film in the present invention, the photosensitive layer on which the cover film is laminated is heated by heat roller ρ when attached to the printed wiring board substrate. It also has a great effect on the storage stability in the step, and it is necessary to pay attention to the weighing accuracy when blending the thermal polymerization inhibitor into the ultraviolet curable resin composition.

(Other additives for 0 include plasticizers, fragrances, dispersants, antifoggants, antistatic agents, adhesion improvers, etc., and these may be added separately, or the above-mentioned It may also be used chemically bonded to formulations in ~tEIK.

As the solvent for C), there are mainly 11! Solvents are used, and ta or mixtures of several solvents are used. Examples include methyl ethyl ketone, toluene, and isopropyl alcohol. In the case of water emulsion system, JP-A-51-9
It is preferable to improve the dispersibility using an emulsifier or the like as disclosed in Japanese Patent No. 4818.

As already described, the compound represented by formula [1] of the present invention is a compound belonging to organic halogen compounds and is a collection of known compounds, some of which are easily available as commercial products. Moreover, it is relatively inexpensive, and can be obtained for about 10% of ααα-tribromomethyphenylsulfone, for example. Moreover, through repeated trial and error, it was discovered that it has an outstanding ability to oxidize the leuco dye and develop color without reducing the polymerization rate, and the present invention was achieved.

Hereinafter, the present invention will be specifically explained based on Examples and Comparative Examples.

Example 1 A colored image-formable ultraviolet curable resin composition was prepared by mixing the following formulations under a yellow safety light. Parts by weight: Methyl methacrylate/2 ethylhexyl V1%/methacrylate/acrylic acid copolymer (molecular weight approximately 50,23.0) Trimethylolpropane triacrylate V-2
．． 0C compound of formula (1)) - Leuco crystal violet 0.
03・Muffkite Green 0
．． 005・2.2'-methylenebis(4-ethyl-6
-t-butylpheno-A/) 0.04 ・Ethylene glyco-A' 0
．． 5. Polyethylene glycol oleay ~ Aete A/
0.05・Methyl ethyl ketone
10.Xylo-A/
t and an untreated PET film with a thickness of 3 μm
This ultraviolet curable resin composition was applied to one side of the support film using a variable vibrator and chipper coater set to 75, and dried for 2 minutes at 80°C in a hot air dryer to form a photosensitive layer. , a photoresist film was prepared. The thickness of the photosensitive layer was 6 μm.

Next, a Gaffus epoxy laminate with an iron base material to which a 35 μm thick copper foil was pasted was made by Guyubon Co., Ltd. A? ! A photoresist film was placed on top of the photoresist film so that the photosensitive layer was brought into close contact with the photoresist film, and the photoresist film was laminated by passing it through a thermoplastic vR layer roll.

Next, a DMBLI optical machine manufactured by Kotoito Co., Ltd. of the United States was operated, and a negative pattern mask was placed on the negative pattern line/1' layer O as a pattern mask, and the film was brought into close contact with vacuum and subjected to second-second exposure.

The illuminance of the exposed surface measured with an ultraviolet illuminance meter (Kuchi V-302) manufactured by Oak Seisakusho was 3.5 mW/-, and the exposure integration i was converted to 7 QmJ/-.

71) The resist film on the laminated plate taken out from the exposure machine shows a purple-blue positive image that faithfully shows the image of the negative 1 screen, and the fine lines between the two bottles are clearly KI.
I could guess it. Next) The CPET film was peeled off and an IX sodium carbonate solution (liquid @ 32''C) was sprayed on it for a second to dissolve and remove the uncured portion of the photosensitive layer.

After this, add Chloride Daini Steel Works, Ching liquid (liquid temperature ω°C) for 4 hours.
The copper foil surface of the removed portion of the photosensitive layer is dissolved and removed to create a wiring pattern, and then a 5X aqueous sodium hydroxide solution C) is sprayed to remove the hardened portion of the photosensitive layer and printed. I got a wiring board.

Upon completion of the etching process, the resist pattern exhibited a deep blue color under a white fluorescent lamp, and no fading by the alkaline solution or etching solution was observed.

Comparative Example I rOH 0.2 parts by weight of ααα-tribromomethylphenyls, A/water was added, and the following steps were carried out in the same manner up to the exposure step.

The photoresist film was a pale blue positive image that vaguely represented the image of the negative mask, and I couldn't tell whether there were two thin lines between the bottles, or whether they were one or two.

Comparative Example 2 Even when the dome film of Comparative Example 1 was exposed for 10 seconds using the same exposure machine, there was almost no difference in color development from that of Comparative Example 1.

〔Effect of the invention〕

As mentioned above, the ultraviolet curable resin composition capable of forming a colored image according to the present invention has a function of accelerating the initiation of photopolymerization as shown by the formula (1)K, and also contains a component capable of producing color when the leuco dye is oxidized. With K, a clear positive image can be obtained, and with this, the use of photoresist film has the effect of greatly contributing to quality improvement in the printed wiring board manufacturing process. be.

Claims (1)

[Claims] (1) (A) Filling polymer (B) Radically polymerizable monomer and/or oligomer having unsaturated double bonds (C) System of ultraviolet polymerization initiator and sensitizer (D) Leuco dye that is originally colorless and necessary Then, dyes (A), (B), (C), and (D) are the main components, and (C
) as a component that generates free radicals by ultraviolet rays in the system, accelerates the initiation of the photopolymerization reaction of (B), and develops color by oxidizing (D). Yes▼ [1] [However, X_1 and X_2 are Br, Br_2, Cl, Cl_
An ultraviolet curable resin composition capable of forming a colored image, comprising a compound or a mixture thereof.