JPH10316887A - Liquid, curable resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition, little discolored by heat or light, quickly curable, excellent in durability after it is cured, and suitable for coating optical fibers, optical fiber tape cores or the like by including a specific photoinitiator. SOLUTION: This composition contains a photoinitiator shown by the formula (Ar1 to Ar3 are each an aromatic), e.g. bis-(2,4,6-trimethylbenzoyl)-phenyl phosphine oxide or bis-benzoyl phenyl phosphine oxide, preferably at 0.1 to 5 wt.% based on the whole composition. It is preferable to use the photoinitiator for curing reactions of urethane (metha)acrylate or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid curable resin composition which hardly causes yellowing of a cured product and has excellent durability.
In particular, it relates to a liquid curable resin composition suitable as a coating material for optical fibers, optical fiber tape core wires, and the like.

[0002]

2. Description of the Related Art In the production of an optical fiber, a resin coating is applied for the purpose of protection and reinforcement immediately after hot-spinning a glass fiber. As this resin coating,
There is known a structure in which a flexible primary coating layer is first provided on the surface of an optical fiber, and a secondary coating layer having higher rigidity is provided outside the primary coating layer. In order to put these resin coated optical fiber wires into practical use, several
For example, it is known to form a so-called optical fiber tape core wire in which four or eight wires are arranged and solidified with a binding material to form a tape-like structure having a rectangular cross section. Then, the resin composition for forming the primary coating layer is a soft material, the resin composition for forming the secondary coating layer is a hard material, and the optical fiber is bundled to form a tape core. Is referred to as a bundling material.

[0003] In recent years, as optical fiber cables have been laid, and as optical fibers are placed in various environments,
Higher durability is desired for soft materials, hard materials, and bundling materials of optical fibers. In addition, the demand for optical fibers increases with the progress of laying, and higher productivity is desired.

[0004]

The curable resin composition used as such a coating material for an optical fiber must be liquid at room temperature and exhibit low viscosity with excellent coating properties; Good property; sufficient strength and flexibility; little change in physical properties with a wide range of temperature changes; excellent heat resistance and hydrolysis resistance; little change in physical properties over time; Excellent long-term reliability; excellent resistance to chemicals such as acids and alkalis; low moisture absorption and water absorption; excellent light resistance; excellent oil resistance; There is a demand for characteristics such as a small amount of hydrogen gas that exerts a negative effect.

[0005] Recently, as the laying of optical fiber cables progresses, higher durability and higher productivity are required. That is, when the durability of the optical fiber coating material is low, for example, when the coloring is remarkable, the visibility of the coloring applied to identify each optical fiber is reduced, which causes trouble in cable maintenance. There was a problem. It has been confirmed that the reduction in visibility is caused not only by the coloring of the bundling material but also by the coloring of the hard material and the soft material. Further, with the growing demand for optical fibers, there is a need for a coating material to be stably cured at a higher speed. In order to cure stably at high speed, the photoinitiator needs to be rapidly decomposed.

A composition containing acylphosphine oxides has been proposed in JP-A-1-190712 as a photocurable resin composition having a high curing rate and realizing high productivity. However, even with the composition proposed in the above publication, the curing speed is not sufficient, and the productivity of optical fiber production cannot be drastically increased while maintaining physical properties as a coating material for optical fibers. Similarly, as a photocurable resin composition having a high curing rate and high productivity, a composition containing bisacylphosphine oxides is disclosed in
No. 259,642. However, bisacylphosphine oxides having a long-chain aliphatic group as exemplified in the above-mentioned publication have poor solubility in the resin composition, and the amount necessary for obtaining a sufficient curing rate is a liquid resin composition. There is a problem that it cannot be dissolved in an object.

[0007]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a liquid material suitable as a coating material for an optical fiber, which hardly discolors and cures at a higher speed under conditions exposed to heat or light. An object of the present invention is to provide a curable resin composition. That is, the present invention provides a liquid curable resin composition containing a photoinitiator having a structure represented by the formula (1) to solve the above problems.

[0008]

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Here, Ar ₁ , Ar ₂ and Ar ₃ each independently represent an aromatic group.

The aromatic groups represented by Ar ₁ , Ar ₂ and Ar ₃ of the photoinitiator having the structure represented by the formula (1) used in the present invention include, for example, phenyl group, methylphenyl group, ethylphenyl Group, dimethylphenyl group, trimethylphenyl group, isopropylphenyl group, tertiary butylphenyl group, methoxyphenyl group, dimethoxyphenyl group, ethoxyphenyl group, diethoxyphenyl group, isopropoxyphenyl group, thiomethoxyphenyl group, naphthyl group, Examples thereof include aromatic groups such as a thiophenyl group and a pyridyl group, which may contain a hetero atom such as an oxygen atom, a sulfur atom, and a nitrogen atom.

Of these, compounds represented by the following formulas (2) to (6) are preferably used as a photoinitiator.

[0012]

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Bis- (2,4,6-trimethylbenzoyl) -phenylphosphine oxide (abbreviation:
BTBPO).

[0014]

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A bis- (2,6-dimethylbenzoyl) phenylphosphine oxide represented by the formula:

[0016]

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A bisbenzoylphenylphosphine oxide represented by the formula:

[0018]

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Bis (2,6-dimethoxybenzoyl) phenylphosphine oxide represented by the formula:

[0020]

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Bisbenzoyl (2,4,6-trimethylphenylphosphine oxide;

More preferably, bis ₁ is a compound of the above formula (2), wherein Ar ₁ is a phenyl group, and Ar ₂ and Ar ₃ are 2,4,6-trimethylphenyl groups.
(2,4,6-trimethylbenzoyl) -phenylphosphine oxide.

These photoinitiators are preferably contained in the composition in an amount of 0.05 to 10% by weight from the viewpoint of improving the curing speed of the liquid curable resin composition and improving the durability of the cured product. More preferably, the content is 0.1 to 5% by weight.

The composition may contain a vinyl polymerizable compound as a component in addition to the above-mentioned photoinitiator. Examples of the components of the vinyl polymerizable compound include (A) urethane (meth) acrylate (hereinafter also referred to as component (A)) and (B) vinyl polymerizable compound (hereinafter also referred to as component (B)).
Are preferred.

The urethane (meth) acrylate of the component (A) can be produced by reacting a polyol, diisocyanate and a hydroxyl group-containing (meth) acrylate. That is, it is produced by reacting an isocyanate group of a diisocyanate with a hydroxyl group of a polyol and a hydroxyl group of a (meth) acrylate containing a hydroxyl group, respectively.

The reaction may be, for example, a method in which a polyol, a diisocyanate and a hydroxyl group-containing (meth) acrylate are charged and reacted at once; a method in which a polyol and a diisocyanate are first reacted, and then a method in which a hydroxyl group-containing (meth) acrylate is reacted; And reacting a hydroxyl group-containing (meth) acrylate and then reacting a polyol; first reacting a diisocyanate and a hydroxyl group-containing (meth) acrylate, then reacting the polyol, and finally reacting the hydroxyl group-containing (meth) acrylate again And the like.

The polyol compound used herein includes, for example, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyhexamethylene glycol, polyheptamethylene glycol,
Examples include polydecamethylene glycol or polyether diol obtained by ring-opening copolymerization of two or more ion-polymerizable cyclic compounds. Examples of the ion-polymerizable cyclic compound include ethylene oxide, propylene oxide, butene-1-oxide, isobutene oxide,
3-bischloromethyloxetane, tetrahydrofuran, 2-methyltetrahydrofuran, 3-methyltetrahydrofuran, dioxane, trioxane, tetraoxane, cyclohexene oxide, styrene oxide, epichlorohydrin, glycidyl methacrylate, allyl glycidyl ether, allyl glycidyl carbonate,
Butadiene monoxide, isoprene monoxide, vinyl oxetane, vinyl tetrahydrofuran, vinyl cyclohexene oxide, phenyl glycidyl ether,
And cyclic ethers such as butyl glycidyl ether and glycidyl benzoate. Further, a polyether diol obtained by ring-opening copolymerization of the above ion-polymerizable cyclic compound with a cyclic imine such as ethyleneimine, a cyclic lactone acid such as β-propiolactone, glycolic acid lactide, or dimethylcyclopolysiloxanes. Can also be used. Specific combinations of the two or more ion-polymerizable cyclic compounds include tetrahydrofuran and propylene oxide, tetrahydrofuran and 2-methyltetrahydrofuran, tetrahydrofuran and 3-methyltetrahydrofuran, tetrahydrofuran and ethylene oxide, propylene oxide and ethylene oxide,
Examples include terpolymers of butene-1-oxide with ethylene oxide, tetrahydrofuran, butene-1-oxide, and ethylene oxide. The ring-opening copolymers of these ionic polymerizable cyclic compounds may be randomly bonded or may be bonded in a block shape.

These polyether diols described so far include, for example, PTMG1000, PTMG2000
(Mitsubishi Chemical Corporation), PPG1000, EXC
ENOL 2020, 1020 (above, Asahi Ohlin Co., Ltd.)
PEG1000, Unisafe DC1100, DC
1800 (all manufactured by NOF Corporation), PPTG200
0, PPTG1000, PTG400, PTGL200
0 (above, manufactured by Hodogaya Chemical Industry Co., Ltd.), Z-3001
4, Z-3001-5, PBG2000A, PBG20
00B (all manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and the like.

As the polyol compound, for example, polyester diol, polycarbonate diol, polycaprolactone diol and the like can also be used in addition to the above-mentioned polyether diol. These diols can be used in combination with a polyether diol. The polymerization mode of these structural units is not particularly limited, random polymerization,
Either block polymerization or graft polymerization may be used.

Examples of the polyester diol used here include ethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, tetramethylene glycol, polytetramethylene glycol, 1,6-hexanediol, neopentyl glycol, and 1,4-cyclohexane. Dimethanol, 3
Polyhydric alcohols such as -methyl-1,5-pentanediol, 1,9-nonanediol, 2-methyl-1,8-octanediol and phthalic acid, isophthalic acid, terephthalic acid, maleic acid, fumaric acid, adipic acid And polyester polyols obtained by reacting with a polybasic acid such as sebacic acid. Commercially available products include Clapol P-2010, PMIPA, PKA-A, and PKA-A
2. PNA-2000 (all manufactured by Kuraray Co., Ltd.) and the like are available.

Examples of the polycarbonate diol include polycarbonates of polytetrahydrofuran and polycarbonates of 1,6-hexanediol. Commercially available products are DN-980, 981, 98 and 98.
2,983 (all made by Nippon Polyurethane Co., Ltd.), PC
-8000 (manufactured by PPG), PC-THF-CD (BA
SF Co., Ltd.).

Further, as the polycaprolactone diol, ε-caprolactone, for example, ethylene glycol, polyethylene glycol, propylene glycol,
Divalent such as polypropylene glycol, tetramethylene glycol, polytetramethylene glycol, 1,2-polybutylene glycol, 1,6-hexanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, and 1,4-butanediol Polycaprolactone diol obtained by reacting with a diol is exemplified. These diols are available in Praxel 205, 205
It can be obtained as a commercial product such as AL, 212, 212AL, 220, 220AL (all manufactured by Daicel Corporation).

Many diols other than those described above can be used. Such diols include, for example, ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, β-methyl -Δ-valerolactone, hydroxy-terminated polybutadiene, hydroxy-terminated hydrogenated polybutadiene, castor oil-modified polyol, polydimethylsiloxane terminal diol compound, polydimethylsiloxane carbitol-modified polyol, and the like.

In addition to using the diol as described above, it is also possible to use a diamine together with a diol having a polyoxyalkylene structure. Examples of such a diamine include diamines such as ethylenediamine, tetramethylenediamine, hexamethylenediamine, paraphenylenediamine, 4,4′-diaminodiphenylmethane, diamines containing a hetero atom, and polyether diamines.

The preferred molecular weight of these diols is usually from 50 to 15,000, particularly preferably from 100 to 8,000 in number average molecular weight. Further, the following substances can be used as the polyol having a ring structure. For example, alkylene oxide addition diol of bisphenol A, alkylene oxide addition diol of bisphenol F, hydrogenated bisphenol A, hydrogenated bisphenol F, alkylene oxide addition diol of hydrogenated bisphenol A, alkylene oxide addition diol of hydrogenated bisphenol F, alkylene hydroquinone Oxide addition diols, alkylene oxide addition diols of naphthohydroquinone, alkylene oxide addition diols of anthrahydroquinone, 1,4-cyclohexanediol and its alkylene oxide addition diols, tricyclodecanediol, tricyclodecanedimethanol, pentacyclopentadecanediol,
Pentacyclopentadecane dimethanol and the like can be mentioned. Of these, alkylene oxide-added diols of bisphenol A and tricyclodecane dimethanol are preferred. These polyols are, for example, Uniol D
It can also be obtained as a commercial product such as A400, DA700, DA1000, DB400 (both manufactured by NOF Corporation) and tricyclodecane dimethanol (manufactured by Mitsubishi Chemical Corporation).

Examples of the diisocyanate include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, 1,5-naphthalene diisocyanate, m Phenylene diisocyanate, p-phenylene diisocyanate, 3,3′-dimethyl-4,4′-diphenylmethane diisocyanate, 4,4′-diphenylmethane diisocyanate,
3'-dimethylphenylene diisocyanate, 4,4 '
-Biphenylene diisocyanate, 1,6-hexane diisocyanate, isophorone diisocyanate, methylene bis (4-cyclohexyl isocyanate),
2,4-trimethylhexamethylene diisocyanate,
Bis (2-isocyanatoethyl) fumarate, 6-isopropyl-1,3-phenyldiisocyanate, 4-
Diphenylpropane diisocyanate, lysine diisocyanate, hydrogenated diphenylmethane diisocyanate, hydrogenated xylylene diisocyanate, tetramethyl xylylene diisocyanate, 2,5-bis (isocyanatomethyl) -bicyclo [2.2.1] heptane, 2,6-bis ( Isocyanatomethyl) -bicyclo [2.2.1] heptane and the like. Of these, 2,4-tolylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, methylene bis (4-
Cyclohexyl isocyanate) and the like.

Further, examples of the hydroxyl group-containing (meth) acrylate include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate and 2-hydroxyethyl (meth) acrylate.
Hydroxy-3-phenyloxypropyl (meth) acrylate, 1,4-butanediol mono (meth) acrylate, 2-hydroxyalkyl (meth) acryloyl phosphate, 4-hydroxycyclohexyl (meth) acrylate, 1,6-hexanediol Mono (meth) acrylate, neopentyl glycol mono (meth) acrylate, trimethylolpropane di (meth)
Acrylate, trimethylolethanedi (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, the following formula (7) or (8): CH ₂ = C (R ¹ ) -COOCH ₂ CH _2- (OCOCH ₂ CH ₂ CH ₂ CH ₂ CH ₂ ) _n -OH (7) CH ₂ = C (R ¹ ) -COOCH ₂ CH (OH) CH ₂ -O- (C ₆ H ₅ ) (8) (wherein, R ¹ represents a hydrogen atom or a methyl group, and n is 1
(Indicating the number of 1 to 15). Further, a compound obtained by an addition reaction of a glycidyl group-containing compound such as alkyl glycidyl ether, allyl glycidyl ether, glycidyl (meth) acrylate and (meth) acrylic acid can also be used. Among these hydroxyl group-containing (meth) acrylates, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate and the like are particularly preferable.

The proportions of the polyol, diisocyanate and hydroxyl group-containing (meth) acrylate are such that the isocyanate group contained in the diisocyanate is 1.1 to 3 equivalents per 1 equivalent of the hydroxyl group contained in the polyol, and the hydroxyl group of the hydroxyl group-containing (meth) acrylate is Is preferably 0.2 to 1.5 equivalents, and it is particularly preferable that the equivalent of the hydroxyl group in the polyol and the acrylate and the equivalent of the isocyanate group in the diisocyanate are substantially equal.

A part of the hydroxyl group-containing (meth) acrylate can be replaced with a compound having a functional group which can be added to an isocyanate group. Such compounds include, for example, γ-mercaptotrimethoxysilane, γ-
Aminotrimethoxysilane and the like can be mentioned.
By using these compounds, the adhesion of a cured product of the composition to a substrate such as glass can be increased.

In the reaction of these compounds, copper naphthenate, cobalt naphthenate, zinc naphthenate, dibutyltin dilaurate, triethylamine, 1,4-diazabicyclo [2.2.2] octane, 2,6,7- It is preferable to use 0.01 to 1 part by weight of a urethanization catalyst such as trimethyl-1,4-diazabicyclo [2.2.2] octane based on 100 parts by weight of the total amount of the reactants. The reaction temperature is usually from 10 to 90 ° C, particularly preferably from 30 to 80 ° C.

The urethane (meth) acrylate of the component (A) thus obtained has a total content of 10 to 90%.
% By weight (hereinafter simply referred to as "%"). Particularly, coating properties when coating optical fiber or the like,
In order to maintain the flexibility and long-term reliability of the coating material after curing, it is preferable to add 20 to 70%.

The liquid curable resin composition of the present invention may further contain a urethane (meth) acrylate obtained by reacting 2 moles of a hydroxyl group-containing (meth) acrylate compound with 1 mole of diisocyanate. Examples of the urethane (meth) acrylate include a reaction product of hydroxyethyl (meth) acrylate and 2,5-bis (isocyanatomethyl) -bicyclo [2.2.1] heptane, and hydroxyethyl (meth) acrylate and 2,6 -Bis (isocyanatomethyl) -bicyclo [2.2.1] heptane reactant, hydroxyethyl (meth) acrylate and 2,4-tolylene diisocyanate reactant, hydroxyethyl (meth) acrylate and isophorone diisocyanate reaction Products, a reaction product of hydroxypropyl (meth) acrylate and 2,4-tolylene diisocyanate, a reaction product of hydroxypropyl (meth) acrylate and isophorone diisocyanate, and the like.

As described above, the liquid resin composition of the present invention can contain the vinyl polymerizable compound as the component (B). Examples of such a vinyl polymerizable compound include lactams containing a vinyl group such as N-vinylpyrrolidone and N-vinylcaprolactam, isobornyl (meth) acrylate, bornyl (meth) acrylate, tricyclodecanyl (meth) acrylate, and dicyclohexane. Alicyclic structure-containing (meth) acrylates such as pentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, and cyclohexyl (meth) acrylate, benzyl (meth) acrylate, 4-butylcyclohexyl (meth)
Acrylate, acryloylmorpholine, vinylimidazole, vinylpyridine and the like can be mentioned. Furthermore, 2-
Hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (Meth) acrylate, amyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, isoamyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (Meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate Relate, undecyl (meth) acrylate, dodecyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, isostearyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, butoxyethyl (meth) acrylate, ethoxydiethylene glycol (Meth) acrylate, benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, methoxyethylene glycol (meth) acrylate, ethoxyethyl (meth) acrylate, methoxy Polyethylene glycol (meth) acrylate, methoxy polypropylene glycol (meth) acrylate, diacetate (Meth)
Acrylamide, isobutoxymethyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, t
-Octyl (meth) acrylamide, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, 7-amino-3,7-dimethyloctyl (meth) acrylate, N, N-diethyl (meth) acrylate
Acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, hydroxybutyl vinyl ether, lauryl vinyl ether, cetyl vinyl ether,
2-Ethylhexyl vinyl ether The following formulas (9) to (1)
1): CH ₂ = C (R ² ) -COO (R ³ O) _m -R ⁴ (9) (wherein, R ² represents a hydrogen atom or a methyl group, and R ³ has 2 to 2 carbon atoms) 6, preferably an alkylene group having 2 to 4; R ⁴ represents a hydrogen atom or an alkyl group having 1 to 12, preferably 1 to 9 carbon atoms; m represents a number of 0 to 12, preferably 1 to 8; Show)

[0044]

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(Wherein R ² has the same meaning as described above;
⁵ represents an alkylene group having 2 to 8, preferably 2 to ⁵ carbon atoms, and p represents a number of 1 to 8, preferably 1 to 4.)

[0046]

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(Wherein R ² , R ⁵ and p have the same meaning as described above, and R ⁶ represents a hydrogen atom or a methyl group)

And the like. Also,
As commercial products, Aronix M-111, M-113,
M-114, M-117 (above, Toa Gosei Chemical Co., Ltd.)
KAYARAD TC110S, R629, R6
44 (all manufactured by Nippon Kayaku Co., Ltd.);
(Manufactured by Osaka Organic Chemical Co., Ltd.).

Examples of the vinyl polymerizable compound of the component (B) include polyfunctional compounds. like this,
Examples of the vinyl polymerizable polyfunctional compound include trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, ethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, and polyethylene glycol di (meth). Acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth)
Acrylate, trimethylolpropanetrioxyethyl (meth) acrylate, tris (2-hydroxyethyl) isocyanurate tri (meth) acrylate, tris (2-hydroxyethyl) isocyanurate di (meth) acrylate, tricyclodecanedimethanol di (meth) acrylate ) Acrylate, di (meth) acrylate of diol of ethylene oxide or propylene oxide adduct of bisphenol A, di (meth) acrylate of diol of ethylene oxide or propylene oxide of hydrogenated bisphenol A, diglycidyl of bisphenol A Epoxy (meth) acrylate in which (meth) acrylate is added to ether, triethylene glycol divinyl ether, and the like can be given. Also,
Commercially available products include, for example, Iupimer UV SA1002,
SA2007 (above, manufactured by Mitsubishi Chemical Corporation); Viscoat 700 (manufactured by Osaka Organic Chemical Co., Ltd.); KAYARAD®
−604, DPCA-20, −30, −60, −12
0, HX-620, D-310, D-330 (all manufactured by Nippon Kayaku Co., Ltd.); Aronix M-210, M-21
5, M-315 and M-325 (all manufactured by Toa Gosei Chemical Co., Ltd.). Among these, especially tricyclodecane dimethanol diacrylate (upimer UV
SA1002) and VISCOAT 700 are preferred.

It is preferable that these vinyl polymerizable compounds are incorporated in the entire liquid curable resin composition in an amount of 15 to 80%, particularly 20 to 70%. If it is less than 15%, not only does the viscosity of the composition become too high, resulting in poor coatability, but also the toughness of the cured product decreases, and the curing shrinkage increases, and if it exceeds 80%, the curing speed decreases. It is not preferable.

In the liquid curable resin composition of the present invention, a compound other than the compound represented by the formula (1) can also be used as a photoinitiator. Moreover, you may add a photosensitizer as needed.

Examples of such photoinitiators that can be used in combination include:
For example, 1-hydroxycyclohexyl phenyl ketone,
2,2-dimethoxy-2-phenylacetophenone, xanthone, fluorenone, benzaldehyde, fluorene, anthraquinone, triphenylamine, carbazole, 3-methylacetophenone, 4-chlorobenzophenone, 4,4'-dimethoxybenzophenone, 4,4'-
Diaminobenzophenone, Michler's ketone, benzoin propyl ether, benzoin ethyl ether, benzyl dimethyl ketal, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 2-hydroxy-2-methyl-1-phenyl Propan-1-one, thioxanthone, diethylthioxanthone, 2-isopropylthioxanthone, 2-chlorothioxanthone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propan-1-one,
4,6-trimethylbenzoyldiphenylphosphine oxide, bis- (2,6-dimethoxybenzoyl)
-2,4,4-trimethylpentyl phosphine oxide; IRUGACURE 184, 369, 651, 50
0, 907, CGI 1700, CGI 1750, CGI
1850, CG24-61 (all from Ciba-Geigy); Lucirin LR8728 (from BASF);
Darocure 1116, 1173 (manufactured by Merck); Ubecryl P36 (manufactured by UCB) and the like. Examples of the photosensitizer include triethylamine, diethylamine, N-methyldiethanolamine,
Ethanolamine, 4-dimethylaminobenzoic acid, 4-
Methyl dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate; Ubecryl P102, 103, 104, 105 (all manufactured by UCB) and the like.

These photoinitiators comprise 0 to 1 in the total composition.
It is preferable to mix 0%, especially 0 to 4%.

The liquid curable resin composition of the present invention may contain, in addition to the above-mentioned components, other oligomers, polymers, and other curable compounds as required within a range that does not impair the properties of the liquid curable resin composition of the present invention. A reactive diluent, other additives and the like can be blended.

Other curable oligomers and polymers include, for example, polyester (meth) acrylate, epoxy (meth) acrylate, polyamide (meth) acrylate, siloxane polymer having (meth) acryloyloxy group, glycidyl methacrylate and other A reactive polymer obtained by reacting a copolymer of a vinyl monomer with acrylic acid is exemplified.

In addition to the above components, various additives such as antioxidants, coloring agents, ultraviolet absorbers, light stabilizers, silane coupling agents, thermal polymerization inhibitors, leveling agents, surfactants, storage stabilizers, A plasticizer, a lubricant, a solvent, a filler, an antioxidant, a wettability improver, a coating surface improver and the like can be blended as required. Here, as the antioxidant,
For example, Irganox 1010, 1035, 1076,
1222 (above, manufactured by Ciba-Geigy), Antigen
P, 3C, FR, GA-80 (manufactured by Sumitomo Chemical Co., Ltd.) and the like; examples of the ultraviolet absorber include Tinuv
in P, 234, 320, 326, 327, 328,
329, 213 (all manufactured by Ciba-Geigy), Sees
orb 102, 103, 501, 202, 712, 70
4 (all manufactured by Cipro Kasei Co., Ltd.); examples of the light stabilizer include Tinuvin 292, 144;
622LD (all manufactured by Ciba-Geigy), Sanol LS
770 (manufactured by Sankyo), Sumisorb TM-0
61 (manufactured by Sumitomo Chemical Co., Ltd.); examples of the silane coupling agent include γ-aminopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, and commercial products As SH6062, 6030 (all manufactured by Dow Corning Toray Silicone Co., Ltd.), KBE9
03, 603, 403 (all manufactured by Shin-Etsu Chemical Co., Ltd.)
And the like.

The viscosity of the liquid curable resin composition of the present invention is usually from 200 to 20,000 cp / 25 ° C.
000-15000 cp / 25 ° C is preferred. And
When the liquid curable resin composition of the present invention is used as a secondary coating material for an optical fiber or a bundling material for a cord, the Young's modulus after curing is 10 to 250 kg / mm.
Is preferably a ^2, when used as the primary coating material of the optical fiber elements, the Young's modulus after curing of 0.05
It is preferably 0.3 kg / mm ² .

The liquid curable resin composition of the present invention comprises:
Cured by heat and / or radiation. Here, radiation refers to infrared rays, visible rays, ultraviolet rays, X-rays, electron beams, α-rays, β-rays, γ-rays, and the like.

[0059]

EXAMPLES The present invention will be described below in more detail with reference to examples, but the present invention is not limited to these examples. In the following, “parts” means “parts by weight”.

Urethane acrylate synthesis example 1 In a reaction vessel equipped with a stirrer, 18.2 g of 2,4-tolylene diisocyanate, 0.055 of dibutyltin dilaurate
g, 2,6-di-tert-butyl-p-cresol 0.017
g and 15.7 g of tricyclodecane dimethanol diacrylate were charged and cooled to 15 ° C. or lower. afterwards,
While stirring, 17.0 g of 2-hydroxyethyl acrylate was added dropwise so that the temperature was kept at 30 ° C. or lower. After the completion of the dropwise addition, the reaction was carried out at 30 ° C. for 1 hour. Next, 3.0 g of tricyclodecane dimethanol (manufactured by Mitsubishi Chemical Corporation) and 30.7 g of a ring-opening copolymer of tetrahydrofuran and 3-methyltetrahydrofuran having a number average molecular weight of 2,000 were added.
The mixture was stirred and reacted at 0 to 55 ° C. The reaction was terminated when the residual isocyanate became 0.1% by weight or less, and a reaction product liquid of a urethane acrylate polymer having a number average molecular weight of 1,670 was obtained. N-vinylpyrrolidone 8.1
g, isobornyl acrylate 6.9 g and Irganox 1
035 (manufactured by Ciba Geigy) was added, and the mixture was stirred while controlling the liquid temperature at 50 to 60 ° C. until a uniform transparent liquid was obtained, to obtain a resin liquid. This resin liquid is designated as UA-1.

Urethane acrylate synthesis example 2 In a reaction vessel equipped with a stirrer, 13.3 g of 2,4-tolylene diisocyanate and 0.04 of dibutyltin dilaurate were added.
g, 2,6-di-tert-butyl-p-cresol 0.012
g and 17.9 g of isobornyl acrylate were charged and cooled to 15 ° C or lower. Thereafter, while stirring, 7.0 g of 2-hydroxyethyl acrylate was added dropwise so that the temperature was maintained at 30 ° C. or lower. After the completion of the dropwise addition, the reaction was carried out at 30 ° C. for 1 hour. Next, PLACCEL 205H (polycaprolactone diol: manufactured by Daicel Chemical Industries, Ltd.) 1
0.0 g, 5.1 g of a polyethylene oxide addition diol of bisphenol A having a number average molecular weight of 400, and 14.5 g of a ring-opening copolymer of tetrahydrofuran having a number average molecular weight of 1,000 and 3-methyltetrahydrofuran were added.
The reaction was carried out at 50-60 ° C. Residual isocyanate
The reaction was terminated when the amount became 1% by weight or less, and a reaction product liquid of a urethane acrylate polymer having a number average molecular weight of 1,650 was obtained. This is 15.9 vinyl caprolactam
g, SA1002 (multifunctional reactive diluent: manufactured by Mitsubishi Chemical Corporation) 8.0 g, lauryl acrylate (manufactured by Kyoeisha Chemical Co., Ltd.) 8.0 g, and Irganox 1035 (manufactured by Ciba Geigy) 0.3 g. Stirring was performed while controlling the liquid temperature at 50 to 60 ° C. until a transparent liquid was obtained, to obtain a resin liquid. This resin liquid is referred to as UA-2.

Urethane acrylate synthesis example 3 In a reaction vessel equipped with a stirrer, 15.9 g of isophorone diisocyanate, 0.046 g of dibutyltin dilaurate,
0.014 g of 2,6-di-t-butyl-p-cresol and tricyclodecane dimethanol diacrylate 1
2.4 g was charged and cooled to 15 ° C. or lower. Thereafter, while stirring, 11.0 g of 2-hydroxyethyl acrylate was added dropwise so as to keep the temperature at 30 ° C. or lower. After the completion of the dropwise addition, the reaction was carried out at 30 ° C. for 1 hour. Next, 4.5 g of a polyethylene oxide-added diol of bisphenol A having a number average molecular weight of 400 was reacted at 20 to 50 ° C. for 1 hour. Thereafter, 26.4 g of polytetramethylene glycol having a number average molecular weight of 2,000 was added and reacted at 50 to 60 ° C. The reaction was terminated when the residual isocyanate became 0.1% by weight or less, and a reaction product liquid of a urethane acrylate polymer having a number average molecular weight of 1,960 was obtained. 9.1 g of N-vinylpyrrolidone, 7.8 g of isobornyl acrylate, 12.5 g of Biscoat 700 (a polyfunctional reaction diluent: manufactured by Osaka Organic Chemical Industry Co., Ltd.), Irganox
1035 (manufactured by Ciba-Geigy) 0.3 g, Tinuvin 29
2 (manufactured by Ciba-Geigy) 0.2 g, diethylamine 0.1
g and SH190 (manufactured by Dow Corning Toray Silicone Co., Ltd.) were added, and the mixture was stirred while controlling the liquid temperature at 50 to 60 ° C. until a uniform transparent liquid was obtained, to obtain a resin liquid. This resin liquid is designated as UA-3.

Urethane acrylate synthesis example 4 In a reaction vessel equipped with a stirrer, 3.3 g of 2,4-tolylene diisocyanate, 51.0 g of a ring-opening copolymer of ethylene oxide and butene oxide having a number average molecular weight of 4,000,
Aronix M-113 (manufactured by Toagosei Co., Ltd.) 22.6
g and 2,6-di-t-butyl-p-cresol 0.0
13 g were charged. Then, these were cooled with ice until the liquid temperature became 10 ° C. or lower while stirring them. When the liquid temperature becomes 10 ° C. or less, dibutyltin dilaurate 0.045 is obtained.
g, and the mixture was stirred for 2 hours while controlling the liquid temperature at 20 to 30 ° C., and then SH6062 (Dow Corning Toray Co., Ltd.).
0.3 g (manufactured by Silicone Co., Ltd.) was added, and the mixture was stirred at 30 to 40 ° C. for 1 hour. After stirring, 1.3 g of 2-hydroxyethyl acrylate was added, and stirring was continued at a liquid temperature of 50 to 60 ° C. for 4 hours. When the residual isocyanate became 0.1% by weight or less, the reaction was terminated, and the number average molecular weight was reduced. Is 8,7
A reaction product liquid of 50 urethane acrylate polymers was obtained. To this, 3.0 g of N-vinylcaprolactam, 10.1 g of Aronix M-114 (monofunctional reactive diluent: manufactured by Toagosei Co., Ltd.), 7.1 g of lauryl acrylate,
0.8 g of Irganox 1035 (manufactured by Ciba-Geigy), SEESOR
0.3 g of B103 (manufactured by Cipro Kasei Co., Ltd.) and 0.1 g of diethylamine were added, and the mixture was stirred at 40 to 50 ° C. to obtain a uniform transparent liquid. This resin liquid is designated as UA-4.

Urethane acrylate synthesis example 5 In a reaction vessel equipped with a stirrer, 6.7 g of 2,4-tolylene diisocyanate and 0.049 of dibutyltin dilaurate were added.
g, 2,6-di-t-butyl-p-cresol 0.051
g, phenothiazine 0.005 g and Aronix M
1113 g of -113 was charged and cooled to 15 ° C or lower. Thereafter, while stirring, 3.0 g of 2-hydroxyethyl acrylate was added dropwise so that the temperature was maintained at 30 ° C. or lower. After the completion of the dropwise addition, the reaction was carried out at 30 ° C. for 1 hour. Next, 51.1 g of a ring-opening copolymer of tetrahydrofuran having a number average molecular weight of 2,000 and 3-methyltetrahydrofuran was added, and the mixture was stirred and reacted at 20 to 55 ° C. The reaction was terminated when the residual isocyanate was 0.1% by weight or less, to obtain a reaction product liquid of urethane acrylate having a number average molecular weight of 4,700. To this were added 11.0 g of isobornyl acrylate, 4.9 g of vinylcaprolactam, 5.7 g of lauryl acrylate and 0.2 g of Irganox 1035.
And adjust the liquid temperature to 40-50 until a uniform transparent liquid is obtained.
The mixture was stirred for 30 minutes while being controlled at ° C. Then 30-4
The mixture was stirred while being controlled at 0 ° C, 0.1 g of diethylamine was added, and the mixture was stirred for 30 minutes. After that, SH6062
0.8 g was added thereto, and the mixture was stirred at 40 to 50 ° C. until the mixture became uniform to obtain a resin solution. This resin liquid is designated as UA-5.

Synthesis Example 6 of Urethane Acrylate In a reaction vessel equipped with a stirrer, 8.2 g of isophorone diisocyanate, 49.0 g of a ring-opening copolymer of ethylene oxide and butene oxide having a number average molecular weight of 2,000, Aronix M-113 25 0.4 g and 0.015 g of 2,6-di-t-butyl-p-cresol were charged. Then, these were cooled with ice until the liquid temperature became 10 ° C. or lower while stirring them. Then dibutyltin dilaurate 0.04
9 g was added and the solution temperature was controlled at 20 to 30 ° C.
Stirred for hours. After that, add SH60620.60g,
Stirred at 30-40 ° C for 1 hour. Then, 3.0 g of 2-hydroxyethyl acrylate was added, and the liquid temperature was 50 to 60.
Stirring was continued at 4 ° C. for 4 hours, and the reaction was terminated when the residual isocyanate became 0.1% by weight or less, to obtain a reaction product liquid of urethane acrylate having a number average molecular weight of 3,870. To this, 3.0 g of N-vinylcaprolactam,
Aronix M-102 (monofunctional positive reactive diluent: Toa Gosei Co., Ltd.) (9.6 g), Irganox 1035 (1.0 g) and diethylamine (0.1 g) were added, and the mixture was stirred at 40 to 50 ° C. to obtain a homogeneous and transparent resin liquid. I got This resin is UA-6
And

Urethane acrylate synthesis example 7 In a reaction vessel equipped with a stirrer, 4.6 g of 2,4-tolylene diisocyanate, 0.041 of dibutyltin dilaurate
g, 2,6-di-tert-butyl-p-cresol 0.012
g, phenothiazine 0.004 g and Aronix M
113. 26.4 g was charged and cooled to 15 ° C. or lower.
Thereafter, while stirring, 2.0 g of 2-hydroxyethyl acrylate was added dropwise so that the liquid temperature was kept at 30 ° C. or lower. After the completion of the dropwise addition, the reaction was carried out at 30 ° C. for 1 hour. next,
Polypropylene glycol 2 with a number average molecular weight of 3,000
6.5 g was added and the mixture was stirred at 20 to 55 ° C. for 1 hour. Thereafter, 17.6 g of polytetramethylene glycol having a number average molecular weight of 2,000 was added and reacted at 50 to 60 ° C.
The reaction was terminated when the residual isocyanate was 0.1% by weight or less, and a reaction product liquid of a urethane acrylate polymer having a number average molecular weight of 5,750 was obtained. 7.0 g of vinylcaprolactam and 15.1 of lauryl acrylate were added thereto.
0 g and 0.3 g of Irganox 1035 were added, and the mixture was stirred for 30 minutes while controlling the liquid temperature at 40 to 50 ° C. until a uniform transparent liquid was obtained. Thereafter, stirring was continued while controlling the temperature at 30 to 40 ° C, and 0.15 g of diethylamine was added.
Stir for 0 minutes, stir at 40-50 ° C until uniform,
A resin solution was obtained. This resin liquid is designated as UA-7.

Examples 1 to 7 and Comparative Examples 1 to 7 Each component having the composition shown in Table 1 was charged into a reaction vessel equipped with a stirrer, and stirred for 3 hours while controlling the liquid temperature at 50 to 60 ° C. Inventive compositions (Examples 1 to 7) and comparative compositions (Comparative Examples 1 to 7) were obtained.

[0068]

[Table 1]

In Table 1, BTBPO is bis- (2,
4,6-trimethylbenzoyl) -phenylphosphine oxide, has a structure represented by the following formula (12), and is included in the photoinitiator represented by the formula (1).

[0070]

Embedded image

Irgacure 184 is a photoinitiator and has a structure represented by the following formula (13).

[0072]

Embedded image

Lucirin is a photoinitiator and has the following formula (1)
It has the structure shown in 4).

[0074]

Embedded image

Irgacure 907 is a photoinitiator and has a structure represented by the following formula (15).

[0076]

Embedded image

BBTPO is bis- (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide and has a structure represented by the following formula (16).

[0078]

Embedded image

Irgacure 184, Lucirin, Irgacure 90
7 and BBTPO are not included in the photoinitiator represented by the formula (1).

Test Examples The liquid curable resin compositions shown in the above examples were cured by the following method to prepare test pieces, which were evaluated as described below. The results are shown in Table 2.

1. Preparation of Test Specimen: A liquid curable resin composition was applied on a glass plate using an applicator bar having a thickness of 250 μm. This was irradiated with ultraviolet rays having an energy of 1 J / cm ² in air. The cured film was used for a heat resistance test by a heating test while remaining on the glass plate. In the test of the curing rate, a cured film was obtained by irradiating ultraviolet rays under a nitrogen stream so that the amount of ultraviolet rays was 10 mJ / cm ² or 100 mJ / cm ² .

2. Heat resistance test by heating test. The test piece was heated in a thermostat at 120 ° C. for 7 days. This test piece was measured using a color difference meter (COLOR ANAL) manufactured by Tokyo Denshoku Co., Ltd.
YZER TC-1800N), the values of ΔE and YI were determined, and the change in hue was measured.

3. Determination of Curing Rate The curing rate was determined by soxhlet extraction of the cured ultraviolet-curable resin using methyl ethyl ketone, followed by vacuum drying, and measurement of the weight (gel content) of the remaining ultraviolet-curable resin. Was. It can be said that the higher the gel content at a lower irradiation dose (10 mJ / cm ² ), the faster the curing speed.

4. Judgment of Solubility When the composition of the composition shown in Table 1 was stirred at 50 to 60 ° C. for 3 hours in a reaction vessel equipped with a stirrer, it passed when the mixture became a uniform transparent liquid. The case where the added solid component remained without being completely dissolved was rejected.

[0085]

[Table 2]

As is clear from Table 2, the cured product using the photoinitiator of the formula (1) has a fast curing speed, has little change in color even under high temperature and irradiation with light, and has good durability. Indicated. The solubility is good and a uniform solution can be obtained by stirring for 3 hours.

[0087]

As described above, the liquid curable resin composition of the present invention provides a material having a high curing speed, excellent durability of the cured product, and less coloring by heat and light. Therefore, when used as a coating material for wood, plastic sheets, optical fibers, and the like, it is an excellent material that can be improved in productivity due to good curability and can be expected to improve the durability of the coated material.

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Miyuki Ishikawa 2--11-24 Tsukiji, Chuo-ku, Tokyo Inside Nippon Gosei Rubber Co., Ltd. No. Japan Synthetic Rubber Co., Ltd.

Claims (1)

[Claims] [Claim 1] The following formula (1) (Here, Ar ₁ , Ar ₂ and Ar ₃ each independently represent an aromatic group.) A liquid curable resin composition comprising a photoinitiator represented by the following formula: