JPH01263646A - Photocurable composition for novel electroless plating - Google Patents

Abstract

PURPOSE:To form a circuit which is produced by a plating method, and has an excellent acid and alkali-proof properties, heat-resisting property and mechanical strength by incorporating a prescribed amount of a polymer which contains a specified repeating structural unit and has a prescribed value of a number- average mol.wt. per a prescribed amount of the polymer contg. the structural unit shown by a prescribed formula in the title composition. CONSTITUTION:The photopolymerizing compd. contg. the repeating structural unit shown by formula II or III, is incorporated in the composition in an amount of 10 to 300pts.wt. of the photopolymerizing compd. per 100pts.wt. of the polymer having the repeating structural unit shown by formula I. In formula I, a vinyl group is substd. at ortho, metha or para position against carbon atom of the main chain of the polymer. The composition contains 0.5 to 100pts.wt. of the polymer which has the repeating structural unit shown by formula II or III and the number-average mol.wt. of 1,000 to 500,000. In formula II, (n) is an integer of 0 to 2, X is a group having an acid group and an ether binding or amino, amide or imide group. The group X is substd. at the metha or the para position against the carbon atom of the main chain of the polymer.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a novel composition, and more particularly to a novel composition having particularly excellent alkali resistance, which is useful for manufacturing high-density printed circuit boards. The present invention relates to a photocurable composition for plating electrolytic steel.

[Conventional technology]

Currently, printed circuit board manufacturing methods can be roughly divided into the following three methods. In other words, there is a subtractive method in which a resist image formed on a copper-clad laminate is used as a protective film to create a prescribed circuit by etching, etc., and a resist image is formed on an insulating plate and chemical copper plating is applied. There are full additive methods, in which a circuit is formed using a single process, and a semi-additive method, which is an intermediate method between the two. Among these methods, the subtractive method is currently the mainstream, but with the technological trend of higher density and higher reliability of substrates, it is becoming more difficult to use through-holes such as high aspect ratio holes and small diameter holes. Semi-additive and full-additive methods are rapidly attracting attention because they have the drawback that hole plating is difficult and the manufacturing process is long and complicated. On the other hand, a wide variety of photocurable resist materials have been developed according to each method, and various properties are required for use in printed circuit board manufacturing. These properties include lithography properties such as sensitivity and resolution, as well as properties such as heat resistance, mechanical strength, acid resistance, and alkali resistance. Among these, electroless copper plating solution resistance, especially high alkali resistance, is important.

Conventionally, photocurable resists that can be used in additive processes, especially dry film photoresists for semi-additive processes, have not had sufficient performance, and the resist image shifts from the substrate during plating. There were problems such as peeling, the inability to use 1.1.1-)lichloroethane as a developer, and low resolution.
It is not suitable for use.

[Problem that the invention seeks to solve]

In light of these technological trends, the present inventors have conducted extensive studies and found that electroless copper has excellent acid resistance, alkali resistance, heat resistance, and mechanical strength, and can be peeled off, especially since it has high alkali resistance. We have discovered a photocurable composition for electroless copper plating that is effective in the process of forming circuits by the plating method, and have accomplished the present invention.

[Means for solving problems]

The present invention is based on 100 parts by weight of a polymer containing a repeating structural unit represented by the following formula (A''l) (hereinafter abbreviated as compound (a)) [However, in formula (A), the vinyl group is ], (a) edge 9 represented by the following formula [B] or (C)
0.5 to 100 parts by weight of a polymer containing a return structural unit and having a number average molecular weight of 1,000 to 500,000 [hereinafter abbreviated as compounds (b) and (C)] [provided that formula (B) n represents an integer from O to 2, X represents a hydroxyl group, a group having an ether bond, an amino group, an amide group, or an imide group; , or substitute in the para position], (b)
The present invention relates to a photocurable composition for electroless copper plating, which contains 10 to 300 parts by weight of a photopolymerizable compound.

The number average molecular weight of the compound (a) that can be used in the present invention is -500 to 1,000,000 in terms of resolution as a photocurable composition, but the sensitivity as a photocurable composition is From the aspect of 5,000 to 500,00
0 is a preferred range.

The vinyl group in formula (A) can be in any of the ortho, meta, or para positions, but is preferably in the meta or para position from the viewpoint of sensitivity as a photocurable composition.

In addition to the repeating structural unit represented by formula (A), compound (a) can have an Rmb repeating structural unit [D] represented by the general formula.

w, x, y and 2 in the repeating structural unit [D] each represent hydrogen, halogen, cyano group, alkyl group having 1 to 6 carbon atoms, halogenated alkyl group having 1 to 6 carbon atoms, or halogenated alkyl group having 1 to 6 carbon atoms. An aryl group having 6 to 30 carbon atoms substituted with an alkyl group or a halogenated alkyl group, an aryl group having 6 to 30 carbon atoms substituted with a group containing a silicon atom, an aryl group having 6 to 30 carbon atoms, -cooal, -co几1. -0-00R4
(R1 is substituted with an alkyl group having 1 to 12 carbon atoms or a halogenated alkyl group, an aryl group having 6 to 30 carbon atoms substituted with an alkyl group having 1 to 6 carbon atoms or a halogenated alkyl group, or a group containing a silicon atom) aryl group having 6 to 30 carbon atoms, or aryl group having 6 carbon atoms
to 30 aryl groups), a nitro group, or a group containing a silicon atom.

A specific preferred combination of w, x, y and Z is (W,
When expressed in the form of (X, Y, Z), (H, H,) I, I ()
, (H+ H+ H+ 06H5), (H, H, H, O
, H4-02H4), (H.

H+ H+ 0toHy)t (Hr II + H
r 014H9), (H, H, OH3°C, H5),
(H+ OHa + H* ClH4S t (0Hs
)a), (H,H.

C6H5+ 061(s), (c, [i51 H+
H* 06H5), (c, n51 H+)! +
01oHy), (0sHs + HJ HI 014
H9), (C1, H7, H, H.

CxoIry), (H,H,H,0OOOH,),
(H, H, H.

C00OF3), (H,H,OH3,0OOOHx)
, (H,H,01°000H3), (H,H,H,
ON), (H, H, H, 0OOC16H,), (H,
H, H, S i (OH3)3), (H+ H+ H
* S r (C6H5)3), etc., but preferred specific examples from the viewpoint of chemical resistance include (H, H, H, H),
(H, H, HI0sHs), (H.

H+ HI C6I(4-C2H4), (Hs H+
Hr 010H7), (H,H.

Hr 014H9), (Hr Hs OH3+ 0aH
s ), (H, OH3, H.

0sHa −S i (CHs)s), (H, H, O,
H5, 0sHs), (C5Hs +H+ H* 0aH
s), (0sHs * Hr H* 010H7), (
0,H5,H.

014H9), (01el”IT r H* H+ 0
1oHy), but is not limited to these.

Furthermore, the repeating structural unit represented by the structural formula CD does not need to be of one type, but can be photocurable by using two or more types in an appropriate ratio or by using a third component. The overall performance of the composition can be improved.

The molar fraction of the ab repeating structural unit represented by formula (A) in compound (a) is generally from 1 to 99%, and preferably from 5 to 95% from the viewpoint of resolution and sensitivity.

Compound (a) that can be used in the present invention is disclosed in JP-A-56-1650.
It can be produced by the method described in Publication No. 9.

The amount of compound (b) or (e) used is the same as that of compound (a).
For 100 parts by weight, the amount is generally 0.5 to 100 parts by weight in terms of compatibility with the compound (,), but in terms of resolution as a photocurable composition, 1 to 80 parts by weight is used. Preferably, from the viewpoint of alkali resistance, the range is more preferably 1 to 50 parts by weight.

The number average molecular weight of compound (b) or (c) is generally 1,000 to 500,000 from the viewpoint of resolution, but from the viewpoint of alkali resistance it is s, ooo or more, and the number average molecular weight is compatibility with compound (,). From this point of view, it is preferably 200,000 or less.

In the formula CB) of compound (b), the substituent -(OH2) -X
The substitution position can be either the meta position or the nozo position.

In formula CB) of compound (b), n may be an integer of 0 to 2, but from the viewpoint of production, n is preferably 0 to 1.

Further, for X, a hydroxyl group, a group having an ether bond, an amino group, an amide group, and an imide group can be used.

Typical examples of groups having an ether bond include methoxy group,
Ethoxy group, butoxy group, cyclohexyloxy group,
Examples include alkyl or aryloxy groups such as phenoxy and benzyloxy groups.

The amino group referred to in the present invention refers to a group represented by the following examples. Examples include an amino group, a methylamino group, an ethylamino group, a cyclohexylamino group, a phenylamino group, a benzylamino group, a naphthylamino group, a dimethylamino group, a diphenylamino group, and a methylethylamino group.

Typical examples of the amide group and imide group include formamide group, acetamide group, benzamide group, methylacetamide group, methacrylamide group, acrylamide group, succinimide group, phthalimide group, maleimide group, dimethacrylamide group, diacrylamide group. etc.

Among the above representative examples, from the viewpoint of resolution and ease of production, methoxy group, ethoxy group, phenoxy group, methylamino group, phenylamino group, benzylamino group, diphenylamino group, acrylamide group, methacrylamide group, acrylamide group A phthalimide group, a dimethacrylamide group, a diacrylamide group, a maleimide group, and the like are preferable, and from the viewpoint of alkali resistance, a diphenylamino group, a phthalimide group, and a methoxy group are even more preferable.

Examples of compound (C) include the following.

In the above formula, the substituent R represents an alkyl group, an aryl group, an acyl group, etc. Specific examples of these include methyl group, ethyl group, butyl group, isozorobyl group, phenyl group, hensyl group, cumenyl group, cinnamyl group, phenethyl group, naphthyl group, anthryl group, and the like. Among these, methyl group, phenyl group, cinnamyl group, etc. are preferable in terms of compatibility with compound (-).

Compound (b) or (C) preferably contains a repeating structural unit [D] in addition to the repeating structural unit represented by formula [B] or (0) for the purpose of increasing compatibility with compound (,). . Specific examples of these preferable repeating structural units are in the format (W, X, Y, Z), (H, II,
Ha0sHs), (H,H,)I, 061-1
4 02H4), (H.

H, H, 0IOH7), ()I, H, Hs 014
H9), (HI HI cHs *06Hs), (H,
H* 08HISe 0sHs).

In the present invention, resistance to electroless copper plating means that when a laminate in which a photocurable layer is laminated on a substrate such as a copper-clad laminate is immersed in an electroless copper plating solution, the photocurable layer peels off from the substrate. This refers to the fact that no effects were observed, such as when the Metsuki reaction occurred, when the Metsuki liquid seeped in, when the Metsuki reaction stopped, and even when the Metsuki reaction went out of control.

The amount of the photopolymerizable compound of the present invention used is compound (a) 100
The range is generally 10 to 300 parts by weight in terms of sensitivity, preferably 20 parts by weight or more in terms of sensitivity of the photocurable layer, and preferably 250 parts by weight or less in terms of resolution. It is. Further, from the overall viewpoint of the photocurable composition of the present invention, a particularly preferable range is 30 to 250 parts by weight.

The photopolymerizable compound referred to in the present invention refers to a functional group such as an acryloyl group, a methacryloyl group, a vinylphenyl group, an allyl group, a cinnamoyl group, a cinnamylideneacetyl group, a benzalacetophenone group, a maleimide group, and a phenylmaleimide group. , a double bond such as a vinylfuryl group, a vinylpyridyl group, a vinylimidazolyl group, and an epoxy group such as a glycidyl group. Common examples of these include cinnamate esters, maleimides, phenylmaleimides, bismaleimides, or trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate,
Acrylic acid esters such as dipentaerythritol hexaacrylate, dipentaerythritol pentaacrylate, dipentaerythritol tetraacrylate, dipentaerythritol triacrylate, acrylates of esters of dicarzenic acid and diols or triols, tris(hydroxyethyl)triazine acrylate, or Methacrylic acid esters corresponding to these,
Acrylamide, methylenebisacrylamide, N-1
- Acrylamides such as butylacrylamide, N-t-octylacrylamide, N-methylolacrylamide, N-butoxymethylacrylamide, N-imbutoxymethylacrylamide, diacetone acrylamide, 2-methyl-3-sulfosylvir acrylamide, triacrylamide formal methacrylamide, styrene, divinylbenzene,
Acrylonitrile, methacryloyl group, ethyl acrylate, inpropyl acrylate, butyl acrylate, cyclohexyl acrylate, benzyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, carpitol acrylate, ethoxy acrylate, methoxypolyethylene glycol acrylate,
2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxy-3-chloropropyl acrylate, 1,4-butylene glycol monoacrylate, dimethylaminoethyl acrylate, diethylaminoethyl acrylate, tetrahydrofurfuryl acrylate, 2-chloroethyl acrylate , 2.
Monoacrylates such as 3-dibromopropyl acrylate, tribromphenyl acrylate, allyl acrylate, and oleyl acrylate, as well as bentanediol, hexanediol, ethylene glycol, tetraethylene glycol, nonaethylene glycol, polyethylene glycol, neopenta/diol, and polypropylene. Examples include, but are not limited to, glycols, acrylic esters or methacrylic esters of diols such as neobentanediol ester of adipic acid, and the like.

For example, monomers such as glycidyl methacrylate and styrene, polyfunctional monomers having a styrene skeleton, or reactive functional groups such as epoxy resins,
In addition, as long as it is photopolymerizable, it can be used as a photopolymerizable compound in the photocurable layer of the present invention, and it may be either liquid or solid at room temperature.

In order to make the present invention more effective, photoinitiators or photosensitizers can be used.

Examples of photopolymerization initiators or photosensitizers that can be used include:
t Polynuclear quinones such as hachenzoin, benzoin alkyl ether, anthraquinone, benzophenone, chlorobenzophenone, Michler's carbon, fleono/, thioxanthone, dialkylthioxanthone, halogenated thioxanthone, naphthalenesulfonyl chloride, azobisisobutyronitrile, 1-azobis-1 -Cyclohexanecarzenitrile, 2,4-dichloropenzoylperoquinde, diphenyl disulfide, dipenzothiazole% 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, 2-hydroxy- 2-methyl-1-phenylpropan-1-one;
Examples include dyes and electron-donating substances such as erythrosine, triethylamine, p-amine benzoates, triphenylphosphine, and 2,2-dimethoxy-2-phenylacetophenone. These photopolymerization initiators or photosensitizers may be used alone or in combination of two or more.

Furthermore, additives such as dyes, stabilizers, and plasticizers can be added to the photocurable composition of the present invention, if necessary.

〔Effect of the invention〕

The photocurable composition of the present invention has good developability and therefore high resolution, and is particularly resistant to mechanical strength of the cured film after exposure, adhesion to the substrate, chemical resistance, and plating solution resistance. It is used as a photoresist material with excellent alkalinity, and has excellent performance in both the copper through-hole method and the solder through-hole method. This has the advantage that the process for producing the upper printed circuit board can be simplified.

It is particularly effective in the process of forming circuits by electroless copper plating, and one preferred embodiment of forming a circuit using the photocurable composition of the present invention is to apply the photocurable composition on a substrate. After laminating the resist composition and exposing and developing a desired pattern with high-energy radiation, copper plating is performed using an electroless copper plating solution. After that, the resist image formed on the substrate is peeled off and a desired pattern is formed. An example is creating a circuit.

The high-energy rays mentioned here are capable of efficiently curing the photocurable layer. Ultraviolet light, deep ultraviolet light, laser light, etc., soft X-rays, electron beams, etc. are also effective for curing the photocurable layer of the present invention.

〔Example〕

Specific embodiments will be shown below with reference to Examples, but the present invention is not limited thereto.

Examples 1 to 10 In a 1λ separable flask equipped with a stirrer, the compound (
a), (b) or (C) [For compounds (a), (b) or (c) used in Examples, see Table-1
Additives shown in Table 2 and Table 3 were added, and the mixture was stirred at room temperature for 15 hours.

Next, each mixture obtained above was coated onto a polyethylene terephthalate film having a thickness of 38 μm as a support using a blade coater so that the film thickness after drying was 50 μm.
After coating, it was dried in a hot air oven at 80° C. for 15 minutes.

Furthermore, the photocurable laminate obtained above was pressure-bonded to a copper-clad glass epoxy laminate using a pressure roll at a temperature of 100°C. The laminate thus obtained was irradiated with light at the exposure amount shown in Table 4 using an ultra-high pressure mercury lamp (Oak Seisakusho, Phoenix 3000 model) through a negative mask film. Then, using a spray nozzle, 1,1.1-
When trichloroethane was sprayed for the time shown in Table 4 to dissolve and remove the unexposed areas, good images were obtained in all cases.

Resist pattern obtained above [from 40 μm to 200 μm
The minimum line width remaining in the independent lines up to μm (20 μm interval) was used as the evaluation of resolution.

Next, the substrate on which the image (100 μm square, 100 turns x 100 pieces) obtained in the same manner as above was formed was placed in a commercially available electroless copper plating solution [Cubojitsu 251, manufactured by Sibley Co., Ltd.] at 550°C for 30 minutes. Soaked for an hour. At this time, the number of residual square turns remaining on the substrate was defined as resistance to electroless copper plating solution. No change in plating speed was observed during this test.

Margin below (note): In the table, the numbers in parentheses represent the added weight (f).

d component d-1 Styron P683 manufactured by Asahi Kasei Corporation d-2 Asaflex AF manufactured by Asahi Kasei Corporation
X-800 d-3 Styron P679 manufactured by Asahi Kasei Corporation e-component e-1 Aronix M-
305JC main component; pentaerythritol triacrylate) e-2 Shin Nakamura Chemical Co., Ltd., "NK Ester BPE-2004 Initiator I-1 Benzyl 1-24.4'-(dimethylamino)benzophenone l
-3 Triphenylphosphine 1-4 Dimethylbenzyl ketal 1-5 Benzophenone dye D-1 manufactured by Mitsubishi Chemical Corporation, "Blue-p" D
-2 Made by the same company, “Green-0”D-3 Made by the same company
Manufactured by "Blue-Q" Margin Table-4 It) ULIυ Comparative Examples 1 to 2 Using mixtures prepared with the following compositions, resolution and electroless copper plating solution resistance were measured in the same manner as in the examples. .

Delpet 70H220f (Asahi Kasei Industries, Ltd.) Trimethylolpropane triacrylate 180t benzophenone 10f Michler's ketone
1.02 Methyl ether ketone (MBK)
39 (1 Styron GP683 180
f trimethylolpropane triacrylate 144t benzophenone 6f Michler's ketone
0.6 rMEK
320F Example 11 The composition obtained in Example 1 was coated using a marker coater.
The film thickness is 59p on the copper clad laminate? It was adjusted and applied so that it was n. Then, it was dried in a hot air oven at 80°C for 10 minutes. When this was exposed and developed in the same manner as in Examples 1 to 10, a good image was obtained.

Patent applicant: Asahi Kasei Industries, Ltd.

Claims (1)

[Claims] Polymer 1 containing a repeating structural unit represented by the following formula [A]
00 parts by weight, ▲ There are numerical formulas, chemical formulas, tables, etc. ▼ [A] [However, in formula [A], the vinyl group is substituted at the ortho, meta, or para position relative to the carbon atom in the main chain. ] (a) Contains a repeating structural unit represented by the following formula [B] or [C], and has a number average molecular weight of 1,000 to 500
,000, 0.5 to 100 parts by weight of the polymer, ▲ formula,
There are chemical formulas, tables, etc. ▼ [B] ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ [C] [However, in the formula [B], n represents an integer from 0 to 2, and
represents a hydroxyl group, a group having an ether bond, an amino group, an amide group, an imide group, and -(CH_2)_n-X is substituted at the meta or para position with respect to the carbon atom of the main chain] (b) A photocurable composition for electroless copper plating, comprising 10 to 300 parts by weight of a photopolymerizable compound.