JPS645695B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a release liquid that is cured by light irradiation and is used to peel off a cured film of a photopolymerizable composition adhered to a substrate from the substrate. When making wiring boards, photopolymerization containing an aqueous alkali-soluble acrylic linear copolymer, a terminal ethylenically unsaturated monomer, and a photoinitiator is carried out on a substrate such as a copper-clad laminate. After coating or laminating and adhering a photoresist composition of the so-called alkaline aqueous solution development type, the photopolymerizable composition film is imagewise cured by imagewise exposure to actinic light; After removing the uncured portion with a sodium carbonate aqueous solution and developing it,
If necessary, a process such as etching with an aqueous ferric chloride solution is performed to remove the unnecessary cured film using a stripping solution. As the stripping liquid, an aqueous solution of an alkali metal hydroxide such as caustic soda or caustic potash is used. The stripping liquid is used many times until the stripping ability decreases, but in order to prevent the workability from decreasing, it is necessary to remove the flakes that have flaked off. Removal of flakes is carried out using a wire mesh, etc., and when removed with an aqueous solution of alkali metal hydroxide, the flakes retain almost the original shape of the cured film, making it easier to plug holes in the wire mesh, etc. It has poor overworkability and is extremely difficult to handle. Another drawback is that it tends to clog the piping of the stripping device. The present inventors have conducted intensive studies to provide a stripping solution that does not have these drawbacks, and have arrived at the present invention. In the present invention, a cured film of the photopolymerizable composition obtained by coating or laminating a photopolymerizable composition developed with an alkaline aqueous solution onto a substrate and then curing the composition with actinic rays is applied onto the substrate. A stripping liquid used when stripping from (a)
Release agent for cured films of photopolymerizable compositions containing 50 to 95 parts by weight of water, (b) 2 to 40 parts by weight of a water-miscible organic solvent, and (c) 0.5 to 40 parts by weight of a water-soluble amine compound. Regarding. The water used in the stripping solution of the present invention may be tap water, distilled water, ion exchange water, industrial water, etc., and these may be used alone or in combination. The amount of water in the stripping solution of the present invention ranges from 50 to 97 parts by weight, preferably from 70 to 95 parts by weight. If the amount of water in the stripping solution of the present invention exceeds 97 parts by weight, the content of the amine compound and water-miscible organic solvent in the stripping solution will decrease, resulting in a longer stripping time, and if the amount of water exceeds 50 parts by weight. When it becomes less than
This is because not only the cost of the stripping solution becomes high, but also the stripping time becomes long. The water-miscible organic solvent used in the present invention includes ethylene glycol monoether, diethylene glycol monoether, and triethylene glycol monoether, either singly or in combination. Examples of ethylene glycol monoethers include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-butyl ether, ethylene glycol-mono-n-propyl ether, ethylene glycol-isopropyl ether, ethylene glycol-isobutyl ether, and ethylene. Examples include glycol monotertiary butyl ether. Examples of diethylene glycol monoether include diethylene glycol monomethyl ether,
Examples include diethylene glycol monoethyl ether, diethylene glycol-n-propyl ether, diethylene glycol iso-propyl ether, diethylene glycol-n-butyl ether, diethylene glycol-isobutyl ether, diethylene glycol-tert-butyl ether, and the like.
Examples of triethylene glycol monoether include triethylene glycol monomethyl ether,
Triethylene glycol monoethyl ether, triethylene glycol-n-propyl ether,
triethylene glycol isopropyl ether,
triethylene glycol-n-butyl ether,
Examples include triethylene glycol isobutyl ether and triethylene glycol-tert-butyl ether. Ethylene glycol monobutyl ether is preferable because the peeling time is short and the peeling pieces are easy to curl. The amount of water-miscible organic solvent in the stripping solution of the present invention ranges from 2 to 40 parts by weight, preferably from 2.5 to 20 parts by weight.
Parts by weight range. If the amount of the water-miscible organic solvent in the stripping solution exceeds 40 parts by weight, the cost of the stripping solution will increase and the stripping time will also become longer; if it is less than 2 parts by weight, the stripping time will become longer and the strips will not become smaller. It is. The water-soluble amine compounds used in the present invention include ethanolamine compounds, polyethylene polyamine compounds, alkylaminoethanol compounds, N-methyl-N,N-diethanolamine, diisopropanolamine, triisopropanolamine, methylimino -Bispropylamine, ethylenediamine hydrate, n-propylamine, 2-amino-1-methylpropanol, morpholine, aminoethylethanolamine, N-aminopropyl-2-pipecoline, etc. are used alone or in combination. Examples of ethanolamine compounds used in the present invention include monoethanolamine, diethanolamine, triethanolamine, and the like. Examples of polyethylene polyamine compounds used in the present invention include ethylenediamine, diethylenetriamine, triethylenetetramine, and tetraethylenepentamine. Examples of alkylaminoethanol compounds used in the present invention include N,N'-dimethylaminoethanol and N,N'-diethylaminoethanol. Ethanolamine compounds, polyethylene polyamine compounds, and alkylaminoethanol compounds are preferred because they have short peeling times. The amount of water-soluble amine compound used in the present invention ranges from 0.5 to 40 parts by weight, preferably from 0.5 to 10 parts by weight. If the amount of the amine compound in the stripping solution of the present invention exceeds 40 parts by weight, the cost of the stripping solution will increase and the stripping time will become longer; if it is less than 0.5 parts by weight,
This is because the peeling time becomes longer. In addition to the above-mentioned components, the stripping solution of the present invention includes methyl ethyl ketone, methanol, ethanol,
It may also contain organic solvents such as isopropyl alcohol and ethylene glycol monobutyl ether acetate, antifoaming agents such as sodium alkyl sulfate and polyoxyethylene sorbitan fatty acid ester, and surfactants. The stripping solution of the present invention can be obtained by uniformly mixing water, a water-miscible organic solvent, and a water-soluble amine compound. It can also be used by mixing it with a predetermined amount of water when using the stripping liquid. Methods for peeling off a cured film of a photopolymerizable composition adhered to a substrate using the stripping solution of the present invention include simply immersing the substrate in the stripping solution, and dipping the substrate in the stripping solution and then blowing air. There are methods of shaking the release liquid by stirring such as bubbling, stirring blades, and ultrasonic vibrations, methods of causing the release liquid to flow down onto the substrate, and methods of spraying the release liquid onto the substrate. A method of dipping and peeling is particularly preferred. When the cured film adhered to the substrate is peeled off using the release liquid of the present invention, the temperature of the release liquid is
The temperature range is preferably from 30 to 70°C, particularly preferably from 40 to 60°C. If the temperature of the stripping liquid is less than 30°C, the stripping time will be undesirably long, and if it exceeds 70°C, the water-miscible organic solvent and the amine compound will easily volatilize, which is undesirable. When the cured film is peeled off using the cured film release liquid of the present invention, the peeled pieces become fragmented and smaller than their original shape, and the peeled pieces become rounded, so remove the peeled pieces with a wire mesh or the like. When separating,
It is less prone to clogging and can be easily separated. The present invention is suitable as a release liquid for adhering a photopolymerizable composition such as that described in Japanese Patent Application No. 54-96570 onto a substrate and peeling off a cured film cured by actinic rays. The above patent application 1977-
No. 96570 contains an acrylic linear copolymer soluble in aqueous alkaline solution with a carboxyl group content of 20 to 50 mol%, a non-gaseous monomer having a terminal ethylenically unsaturated group, and a Alkaline aqueous solution development type photopolymerizable compositions containing a photoinitiator that generates free radicals have been proposed. Next, the present invention will be explained by examples. Example 1 Copper surface polished and cleaned; length 200mm, width 100mm
mm, an alkaline water developable type photosensitive film phototec on the copper surface of a copper-clad laminate with a thickness of 1 mm.
- Peel off the protective film from 860AFX (trademark manufactured by Hitachi Chemical Co., Ltd.) and place the support film on top.
A test plate was prepared by laminating the layers at 160° C. and exposing the entire surface to light (120 mJ/cm ² ) using a mercury lamp. Tap water
2100g of monoethanolamine, 30g of butyl cellosolve, 140g of butyl cellosolve, and 60g of ethylene glycol monobutyl ether acetate were placed in an ultrasonic cleaner (BRANSONIC32 manufactured by Brason), and after the temperature of the liquid was 50℃, while oscillating ultrasonic waves. The support film was removed from the test plate, and the test plate was immersed in a peeling solution vertically to observe the peeling state. Peeling started 1 minute and 30 seconds after immersion and was completed in 2 minutes and 10 seconds, but the peeled pieces were broken into small pieces and were in a balled state, making them easy to pass through. On the other hand, a similar test was conducted using a 5% caustic soda aqueous solution at 50°C, but the flakes were hardly divided into pieces and did not curl up. When we compared the susceptibility using a wire mesh with a 3 mm grid, we found that the material that was removed using the stripping liquid of the present invention remained in small circles on the wire mesh and could be easily filtered through a furnace. On the other hand, the flakes removed with a caustic soda aqueous solution had large flakes, and the holes in the wire mesh were blocked, resulting in very poor furnace resistance. Example 2 Polished and cleaned copper surface 200mm vertically and 100mm horizontally
mm, an alkaline water developable type photosensitive film phototec on the copper surface of a copper-clad laminate with a thickness of 1 mm.
- Peel off the protective film from 860AFX (trademark manufactured by Hitachi Chemical Co., Ltd.) and place the support film on top.
After laminating at 160°C, an image film with transparent holes of 40 mm in diameter for actinic light was placed on the photosensitive surface on a grid of 50 mm intervals, and exposed using a mercury lamp (120 mJ/cm ² ) to form a test plate. 100 pieces were made. Remove the support film from the test plate and
Ultrasonic cleaning machine (manufactured by Branson)
The film was developed by immersion in a 2% sodium carbonate aqueous solution in BRANSONIC32) at 36°C for 60 seconds, cleaned with water, solder-plated, and washed with water. 80 kg of industrial water pumped from underground, 11 kg of ethylene glycol monobutyl ether, 3 kg of diethylene glycol monobutyl ether, ethylene glycol monoethyl ether
0.8Kg, ethylene glycol monoethyl ether acetate 0.2Kg, monoethanolamine 3Kg,
1 kg of diethanolamine and 1 kg of dimethylaminoethanol were placed in a tank and mixed for 5 minutes using a Satake stirrer to prepare a stripping solution of the present invention. The above-mentioned stripping solution was put into a spray stripper (a modified version of the etching machine SYSTEM547 manufactured by CHEMCUT), the temperature of the stripping solution was adjusted to 50℃, and 100 test plates were solder-plated as described above in succession. and peeling was performed (required spray time: 2 minutes). The stripping solution was filtered through a wire mesh with a 2 mm lattice and circulated for reuse, but the strips were broken up into small pieces and rolled into balls, making it easy to filter. Example 3 Three test plates were prepared in the same manner as in Example 1.
The following solutions A, B and C were prepared as stripping solutions. Solution A represents an embodiment of the invention, solutions B and C
indicates a comparative example (no amine compound and no organic solvent used). Parts are by weight. Solution A Ion exchange water 50 parts Monoethanolamine 2 parts Ethylene glycol monobutyl ether 2 parts Solution B Ion exchange water 50 parts Monoethanolamine 4 parts Solution C Ion exchange water 50 parts Ethylene glycol monobutyl ether 4 parts Solution A, B and C 50 per beaker each
The mixture was warmed to ℃ and stirred using a magnetic stirrer. A test plate was immersed vertically in the solution, and the state of peeling was observed. The results are shown in Table 1.

[Table] As shown in the above examples, the stripping liquid according to the embodiment of the present invention has the advantage of making the stripping work easier in that it divides the strips into smaller pieces and the strips become rounded. .

Claims (1)

[Claims] 1. A photopolymerizable composition obtained by coating or laminating a photopolymerizable composition of an alkaline aqueous solution development type onto a substrate, and then curing the composition with actinic rays. A release liquid used when peeling off a cured film from a substrate, comprising: (a) 50% water;
97 parts by weight, (b) 2 to 40 parts by weight of a water-miscible organic solvent, and (c) 0.5 to 40 parts by weight of a water-soluble amine compound. 2. A release liquid for a cured film of a photopolymerizable composition according to claim 1, wherein the water-miscible organic solvent is ethylene glycol monobutyl ether. 3. Claim 1, wherein the water-soluble amine compound is one or more amine compounds selected from the group of ethanolamine compounds, polyethylene polyamine compounds, and alkylaminoethanol compounds. A release liquid for a cured film of the photopolymerizable composition according to item 2.