JPS6127535A - Photosensitive resin composition - Google Patents

Abstract

PURPOSE:To obtain a photosensitive resin compsn. capable of forming a permanent protective film by mixing a photopolymerizable unsatd. compd., a photopolymn. initiator, a halogenated epoxy resin, and a specified linear polymer. CONSTITUTION:The photosensitive resin compsn. is prepared by polymerizing a mixture of (a) a photopolymerizable unsatd. compd. having at least two terminal ethylene group; (b) a photopolymn. initiator; (c) a halogenated compd. having at least two epoxy group; and (d) a compd. represented by the formula, R1 being H, methyl, or halogen, and each of R2, R3, and R4 being an aliphatic or aromatic hydrocarbon group, as one component, and dissolving the obtained linear polymer in a proper solvent. This compsn. can be photopolymerized by irradiation of actinic rays and a permanent protective film thermally stable at a temp. of <=80 deg.C can be formed.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a photopolymerizable photosensitive resin composition for image formation.

(Prior art) Conventionally, a resin composition made of a polymeric material such as a paint, a polymerizable sensitizer, and a polymeric sensitizer is coated or coated on a substrate, and active light such as ultraviolet rays is irradiated through a negative image or the like. irradiate and polymerize or crosslink the exposed area
It is known that the above-mentioned image can be developed on a substrate by making it insoluble in a solvent and eluting the portions that are not exposed to light, and is used in the production of printing plate materials and printed wiring boards.

However, the image coating obtained with the above composition has insufficient solvent resistance, chemical resistance, heat resistance, and mechanical strength.
Its use as a protective coating is limited.

For example, these films can withstand neutral and weakly acidic solutions, but cannot withstand strongly acidic and alkaline solutions, thus limiting the types of processing solutions for etching, plating, etc. Furthermore, it cannot be used as a permanent protective film because it is sensitive to organic solvents such as toluene, trichlene, and methyl ethyl ketone, and has insufficient heat resistance and mechanical strength.

Furthermore, for the purpose of forming a permanent protective film, 49 systems containing epoxy compounds and their curing agents have been proposed, but these systems require a short curing time of one hour at room temperature and a long period of time at high temperature for curing. This may cause the board to warp or cause metal corrosion.

Special Publication No. 52-43092, Special Publication No. 52-4309
1, Japanese Patent Publication No. 56-3539, etc., attempts have been made to include an acid component in a copolymer binder to accelerate curing in order to form a permanent protective film, but under normal conditions. However, the curing is insufficient, the soldering heat resistance, solvent resistance, and alkali resistance are poor, and furthermore, the cold and heat cycle characteristics are not sufficiently improved, and no efforts have been made to improve flame retardancy. Furthermore, JP-A No. 53-56018 proposes that when a copolymer containing acrylonitrile is used as a binder and 5% or more of a halogen is included in the composition, flame retardancy is imparted by K. However, since the binder does not participate in crosslinking, the crosslinking density is low and various properties of the solder resist are insufficient.

(Object of the Invention) The present invention solves the above-mentioned conventional drawbacks and provides a photosensitive film suitable for forming a permanent protective film that is flame retardant, has excellent storage stability, and can be cured in a short time. The purpose of the present invention is to provide a resin composition with a high level of properties.

(Summary of the Invention) The summary of the present invention is as follows: (-1) A photopolymerizable unsaturated compound having at least two terminal ethylene groups; and has a halogen group, (dl A linear polymer compound polymerized using a compound represented by the following general formula as one component, (R1 group selected from hydrogen, methyl, and halogen, Rs
*Rs *R4ke Aliphatic hydrocarbon or aromatic hydrocarbon (can contain oxygen, sulfur, and nitrogen)
] A photosensitive resin composition characterized by consisting of or having this as a main component.

(Structure of the Invention) The unsaturated compound according to the present invention (1) has substantially at least two terminal ethylene groups, has substantially at least two terminal ethylene groups, and has only one terminal ethylene group in the system. There may be compounds having three or more terminal ethylene groups, and this means that one compound has at least two terminal ethylene groups on average as a whole.

The most suitable unsaturated compounds are acrylic esters or methacrylic esters of polyhydric alcohols, such as triethylene glycol, -traethylene glycol, ethylene glycol, propylene glycol, trimethylolpropane, pentaerythritol, Examples include acrylic acid and methacrylic esters such as pentyl glycol. The usage amount of this component #ia is 10 to 90% by weight in the photosensitive resin composition, preferably 1
It is 5 to 60% by weight.

The sensitizer (bl) in the present invention is one that initiates polymerization of the unsaturated compound upon irradiation with actinic light, and in some cases, a main sensitizer and a secondary sensitizer that increases the action of the main sensitizer. Sometimes used in combination.

As the sensitizer (b), conventionally used sensitizers can be used, but phenylketone-based sensitizers are particularly preferred, and specifically, benzophenone sp+T''-bis(dimethylamino ) p-1 minophenyl ketone such as benzophenone (hereinafter referred to as Michler's ketone), benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin butyl ether, pentwinisopropyl ether, benzyl-anthraquinone, 2-methylanthraquinone, 2-ethyl Anthraquinone, 2-1
-butyl-anthraquinone, 2-aminoanthraquinone and the like.

The above-mentioned sensitizers (b) have similar effects, and by combining those with different active light absorption ranges, the polymerization initiation efficiency can be improved and the exposure time can be further shortened. Particularly suitable is a mixture of 1-benzophenone and Michler's ketone. The amount of this component used is 0 in the photosensitive resin composition.
．． 01-151-15% by weight, preferably 0.1-10% by weight.

Compound (c) in the present invention is a Flrll halogenated epoxy resin containing essentially two epoxy groups. This means that substantially at least two are included.

Examples of the halogenated epoxy resins include epoxy resin prepolymers obtained by brominating or chlorinating bisphenol A or novolak skeletons, specific examples include Epicote 1045.1046.1.
050 (all trade names from Shell), Aralgate 8G11゜8024.8049 (all trade names from Ciba Geigy), etc., and the halogenation rate is 5 to 80.
% by weight is preferred.

These compounds (Cl) may be used alone or in combination, and the amount used is 5 to 80% by weight, preferably 15 to 70% by weight, in the photosensitive resin composition.

Several methods are known for making photopolymerizable compositions flame retardant. The first method is to add antimony oxide as a flame retardant to the composition, but although a high level of flame retardation can be achieved, some of the properties of the composition are deteriorated. Therefore, it is necessary to reduce the amount of antimony oxide added or completely remove it. Therefore, in the present invention, in order to achieve flame retardant standards and avoid the adverse effects that occur when antimony oxide is added, compound (c)
ingredients are used.

Conventionally, latent curing agents include boron trifluoride monoethylamine, boron trifluoride benzylamine complex, tetrafluorofluoride salt, adipic acid, dihydrazide, triethylaminoporan, phenylenecyamine-zinc bromide complex, There are dicyandiamiy, etc., but the visible time at room temperature is too short,
Storage becomes impossible.

As a latent curing agent with a long room temperature visible time, p, p/-
Diaminodi7-methylmethane%pH)'-diaminodizenyl sulfonic acid, 2-ethyl-4-ethyl imiguzole, etc. have also been found, but because they require high temperatures and long periods of time to cure, they may cause warping of the substrate or processing problems. It takes a long time and I don't like it.

Further, the above-mentioned conventional latent curing agents are not suitable for manufacturing printed wiring boards because they may diffuse into the metal surface of the substrate and have an adverse effect on the electrical properties of precision electrical circuits.

Therefore, as a result of intensive studies, the present inventors have discovered a linear polymer compound fdl that is polymerized using the compound (d-1) represented by the following general formula as a -component.

(R1 group selected from hydrogen, methyl, halogen, R2
, Rs, Rake aliphatic hydrocarbon or aromatic hydrocarbon (however, it may contain oxygen, sulfur, nitrogen)] The above linear polymer compound (dl acts as a latent curing agent, and the photosensitive resin composition As a product, the pot life at room temperature is long enough.
When cured in one hour at an appropriate temperature to form a permanent protective film, excellent solvent resistance, alkali resistance, and soldering heat resistance can be obtained.

In the compound (d-1) of the general formula (I), if the aliphatic hydrocarbon or aromatic hydrocarbon of R2-R4 is too long, sufficient heat resistance cannot be obtained. R2-R4 are preferably ethyl groups, and up to hexyl groups are practical.

Further, R and to R4 may contain an oxygen atom in the form of an ether bond or a hydroxyl group, or may contain sulfur or nitrogen. R-
The most suitable case for ~R4 is the case where it has a carbon-carbon double bond.

Although the reasons for these are not clear, the compound (d-1) of the general formula (Il) has appropriate polarity to be uniformly dispersed in the photosensitive resin composition, and does not bleed and adversely affect the substrate surface. it is conceivable that.

Further, when R2 to R4 contain a double bond, it is assumed that the double bond is incorporated into the polymerization system upon irradiation with actinic light, and has a favorable effect on the dispersibility and curing of compound (e).

As the compound (d-1) represented by general formula (I),
For example, 1,1-dimethyl-1-(2-hydroxy-3
-butoxypropyl)amine-methacrylimide, 1.
1-dimethyl-(2-hydroxy-3-acryloyloxypropyl)amine-methacrylimide, 1,1-dimethyl-1-(2-hydroxy-3-acryloyloxypropyl)amine-methacrylimide, 1,1-dimethyl- Examples include 1-(2-hydroxy-3-methacryloyloxypropyl)amine-methacrylimide.

The above compound (d-'1) can be polymerized to oligomerize and have a high molecular weight by a conventional method, or preferably copolymerized with other polymerizable polymers to form a linear polymer compound (d). is obtained. When compound (d-1) is polymerized alone, the molecular weight is preferably in the range of 1,000 to 20,000, and the amount #'i used is 1/30 in the photosensitive resin composition.

As other polymerizable monomers to be copolymerized with compound (d-1), methyl (meth)acrylate, butyl (meth)acrylate, styrene, maleic anhydride, etc. can be used. When these polymerizable nanatsumers are copolymerized and made into a high molecular weight product, 1g of skin can be obtained as is! It can be used as a formable binder, and when a compound such as polymethyl methacrylate is used as a binder, the compound (d-1) can be copolymerized with a monomer common to the binder.
It is possible to prepare a composition that has good compatibility and does not cause a bleed effect.

When compound (d-1) is copolymerized with another polymerizable hexamer, the compound (d-1) should be in the range of 1 to 15% by weight and the molecular weight should be in the range of 100,000 to 300,000. preferable.

At this time, the amount of linear polymer compound (dl used is 10 to 90
The weight percent is preferably in the range of 30 to 601i weight percent.

Linear polymer compound (d) #'1150℃ explained above
The compound (Cl) is rapidly cured in the dark for 10 to 30 minutes, providing excellent alkali resistance and improving solvent resistance and sintering heat resistance. d
) significantly improves the storage stability at room temperature, and the curability of compound (e) at high temperatures is good. This is a linear polymer compound (compound (d
It seems that the -1') portion is maintained at an appropriate level and suppresses the curing of the epoxy at room temperature.

Furthermore, unlike general latent curing agents, the linear polymer compound (d-1) does not have any adverse effects on the substrate surface due to bleed effects, such as electrical properties, and can be used for substrate-to-resist resistance due to repeated cooling and heating. This has the effect of preventing peeling and cracking at the interface between the two.

In addition to the above-mentioned essential components, the photosensitive resin composition of the present invention includes:
It is possible to include secondary ingredients for various purposes. That is, they include plasticizers, adhesion improvers, dyes, pigments, and other fillers for improving storage stability.

(Action of the invention) The photosensitive resin composition of the present invention has photosensitivity like ordinary photosensitive resins, undergoes photopolymerization when irradiated with actinic light, and is sufficiently thermally stable at temperatures below 80°C. A permanent protective coating can be formed using conventional methods.

That is, the photosensitive resin composition of the present invention is usually 3 to 60% by weight.
Methyl ethyl ketone, toluene,
The solution is prepared by dissolving it in an organic solvent such as methyl selonulf or chloroform, and a photosensitive layer is formed on the substrate to be protected by the method (1) or 12+ below.

11) A stone in which a solution containing a photosensitive resin composition is applied onto a substrate and dried.

(2) A solution in which the photosensitive resin composition is dissolved is applied to a film such as polyethylene terephthalate and dried. The obtained film is attached to a substrate using a hot roll. In this case, the photosensitive layer of the film will hold 1! [Films are sometimes stored in layers.

The substrate on which the photosensitive layer is formed is irradiated with active light such as ultraviolet rays through a negative mask, and the exposed areas are cured by photopolymerization and crosslinking. Next, the unexposed areas are exposed using 1.1.1-trichloroethane or the like.

Elute and perform the phenomenon. The image-like protective coating S obtained in this way becomes a corrosion-resistant film for ordinary surface modification processing such as etching and plating, but it can also be heat-resistant and Provides a permanent protective coating with excellent mechanical strength. This protective coating can be applied to aromatic hydrocarbons such as toluene, ketone solvents such as methyl ethyl ketone,
It is not attacked by halogenated hydrocarbon solvents such as methylene dichloride, and has sufficient resistance to aqueous alkaline solutions.

Therefore, it can be used as a permanent protective film such as a solder resist that has excellent soldering heat resistance. In addition, prior to heat curing, post-exposure to ultraviolet rays or the like at an intensity of 1 to 3 rays can also form a protective film with excellent strength.

Furthermore, since the photosensitive resin composition of the present invention has excellent photosensitivity and chemical and physical strength, it can be used as a photosensitive adhesive, a photosensitive paint,
It can also be used as a plastic relief or printing plate material.

[Example] The present invention will be described in detail below. Note that "parts" means "parts by weight."

<Example 1> Methyl methacrylate/1,1-dimethyl-1-(2-
Hydroxy-3-butoxypropyl)amine-methacrylimide (90/10) copolymer (1! Weight average molecular weight 2
00,000 parts) 30 parts pentaerythritol triacrylate 30 parts Jepoxy ether of monobromobisphenol A (halogen content 12%) 30 parts benzophenone 3 parts Michler's ketone (LS part p-methoxyphenol (more than 15 parts methyl ethyl ketone 20 parts)
A photosensitive composition was prepared by dissolving in 0 parts. This is 40
When a storage test was conducted at ℃, it was confirmed that it had sufficient light and heat curing properties even if it was left for more than 6 months.

In addition, according to Anderers Laboratories 94 test (hereinafter referred to as UL94 test) K, 5
A combustion test was conducted by heating an IJ tube at 150°C for 20 minutes.It was coated and dried on polyethylene terephthalate of the same thickness for the first and second ignition, and a photosensitive layer of sopm thickness was applied. was formed.

It was laminated under pressure on a cleaned copper plate using a hot roll.

And toomJ/ from high pressure mercury lamp through negative mask.
− was irradiated with ultraviolet rays. 1.1.1-) Peel off the polyethylene tele 7 crate film and add 9
The unexposed areas were eluted and developed by spraying for 0 seconds. Next, heat treatment was performed at 150° C. for 20 minutes, and a protective film with a precise image corresponding to a negative mask was obtained. This protective film showed no change even after being immersed in methyl ethyl ketone, acetone, chloroform, trichlene, methanol, 10% sulfuric acid aqueous solution, toluene, and xylene for 1 day each, and was further immersed in a sodium hydroxide aqueous solution with a pH of 12 at 70°C for 1 day. However, no abnormality was observed.

Also, heat and cool from -65℃ to 125℃ for 10 minutes at 60 minute intervals.
Repeat 0 times, then put it in a hot water bath at 260-270℃ for 2 days.
There was no change even after immersion for a period of time.

Example 2> Methyl methacrylate/1,1-dimethyl-1-(2-
Hydroxy-3-butoxypropyl) amine-methacrylate imide (9071G) copolymer (weight average molecular weight 200,000) 30 parts Pentaerythritol triacrylate 30 parts Diarylk≧Udate (C15HizC1i04) (Halogen content 45%) 30 parts Benzophenone 3 michler ketone
Part 5 p, -methoxyphenol
A photosensitive composition was prepared by dissolving 0.5 parts or more in 200 parts of methyl ethyl ketone. When this was subjected to a storage test at 40°C, it was confirmed that it had sufficient light and heat curing properties even when left for more than 6 months. .

According to the UL94 test, five test strips prepared from solution were heated for 150'Cl2O minutes and subjected to a combustion test, with an average combustion within 5.0 seconds after each of the first and second ignitions. It was time.

Other characteristics were the same as in Example 1.

<Example 3> Methyl methacrylate/1.1-dimethyl-1-(2-
Hydroxy-3-butoxypropyl) amine-meccrylate imide (90/10) copolymer (weight average molecular weight 200,000) 30 parts pentaerythritol triacrylate 30 parts tetrabromobisphenol A
jepoxy ether (halogen content 46-50%)
[Product name: Araldite 8049 Ciba Geigy]
ao part benzophenone
Part 3 Michler Ketone o, s
A photosensitive composition was prepared by dissolving 0.5 parts or more of p-methoxyphenol in 200 parts of methyl ethyl ketone. When this was subjected to a storage test at 40℃,
It was confirmed that it had sufficient light and heat curing properties even after being left for more than 6 months.

According to the UL test, five test strips prepared from solution were heated at 150°C for 20 minutes and subjected to a combustion test, and after each of the first and second ignition,
The average burning time was within 4 seconds.

Other characteristics were the same as in Example 1.

Comparative Example 1> Methyl methacrylate/1.1-dimethyl-1-(2-
Hydroxy-3-butoxypropyl) amine-meccrylate imide (9071G) copolymer (weight average degree of polymerization: 200,000) 30 parts Pentaerythritol triacrylate 30 parts Epoxy resin [Product name: Epicote 828 Shell Company] 30 parts Benzophenone 3 Part Michler's Ketone O,S Part p-Methoxyphenol A 5 parts or more were dissolved in methyl ethyl 2009 to prepare a photosensitive resin composition.

According to the UL test, five test strips prepared from solution were heated for 150'Cl2O minutes and burned for more than 30 seconds after each first and second ignition.

Comparative Example 2 Trimethylolpropane triacrylate 25 parts Tetrabromobisphenol A di(3-acryloxy-2-hydroxyprobyl) ester (halogen content 50%) 40 parts Benzophenone
Part 6 Michler Ketone
15 parts polymethyl methacrylate io
Methylmethacrylate-acrylonitrile-glucodiene-styrene (46/9/14/31) copolymer 3
The photosensitive resin prepared by adjusting the iso part or more of 3 parts of methylene chloride melted when immersed in solder at 260 to 270°C for 2 minutes, and came off from the laminated copper plates.

(Effects of the Invention) As described above, the photosensitive resin composition of the present invention is flame retardant, has excellent storage stability, and when curing, the reaction proceeds sufficiently at a relatively low temperature in a short period of time. Solvent resistant, alkali resistant,
A protective film with good heat resistance can be formed.

Claims (1)

[Claims] 1. (a) a photopolymerizable non-corrosive compound having at least two terminal ethylene groups; (b) a photopolymerizable sensitizer; (c) containing at least two epoxy groups. , and a compound having a halogen group; (d) A linear polymer compound polymerized using the compound represented by the general formula below as one component; selected group, R
_2, R_3, and R_4 are aliphatic hydrocarbons or aromatic hydrocarbons (however, they may contain oxygen, sulfur, and nitrogen)] A photosensitive resin composition consisting of or having these as a main component. 2. The photosensitive resin composition according to claim 1, wherein the compound (c) has a halogen content of 15% by weight or more. 3. The photosensitive resin composition according to claim 1 or 2, wherein the halogen in the compound (c) is bromine.