JPH08113621A - Liquid curable resin composition - Google Patents

Abstract

PURPOSE: To obtain a curable liq. resin compsn. which gives a cured article exhibiting a low tensile modulus, small temp. dependence in a low-temp. zone, improved adhesion to glass, and improved releasability by incorporating a specific urethane (meth)acrylate, a (meth)acrylate compd., and a polymn. initiator into the same.

CONSTITUTION: With a diol compd. contg. 2-50 wt.% structural units of formula I and 20-98 wt.% structural units of formula II and having a number average mol.wt. of 200-1000, a diisocyanate compd. in such an amt. that the amt. of NCO group is 1.1-3 equivalents per equivalent of OH group of the diol compd., and a hydroxylated (meth)acrylate compd. in such an amt. that the amt. of OH group is 1.5 equivalents per equivalent of OH group of the diol compd. are reacted to give a urethane (meth)acrylate (A) having a number average mol.wt. of 1,000-20,000. 15-70 wt.% ingredient A is compouned with 10-70 wt.% (meth)acrylate compd. (B) which gives a homopolymer having a glass transition temp. lower than 0°C, giving a liq. curable resin compsn. The compsn. is compounded with 0.1-10 wt.% polymn. initiator and is cured by heat or a radiation to give a cured article which satisfies the formula III and IV [wherein x and y are tensile moduli (kg/mm²) at 23°C and -40°C, respectively].

COPYRIGHT: (C)1996,JPO

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a liquid curable resin composition. More specifically, the present invention relates to a liquid curable resin composition which has a low tensile elastic modulus at room temperature and gives a cured product having a very small temperature dependency of the tensile elastic modulus in a low temperature region of room temperature or lower. Furthermore, the present invention provides a cured coating film having an excellent balance between adhesion to glass and releasability, and as a result, relates to a liquid curable resin composition suitable as a primary coating material for optical fibers.

[0002]

2. Description of the Related Art Since glass fibers used for optical fibers are brittle and easily damaged, they are coated with an ultraviolet (UV) curing resin for protection and reinforcement.
U used as a primary coating material among optical fiber coating resins
The V-curing resin is required to have a low tensile elastic modulus in order to prevent transmission loss due to structural irregularity or microbending that occurs at the interface between the glass fiber and the covering material. Furthermore, with the recent increase in density of optical cables, a primary coating material with a tensile elastic modulus lower than that of the conventional one is required for the purpose of reducing transmission loss, and optical fibers are transmitted under various temperature conditions. There is a need for a primary coating material that has a small temperature dependence of the tensile modulus even at low temperatures so that it can be used with a small loss.

Further, when connecting an optical fiber at its end, it is necessary to partly remove the coating material. Therefore, the primary coating material must have a proper adhesion to the glass fiber so that structural irregularities and micro-bending do not occur, and an appropriate peeling property from the glass fiber is also required, and a good balance between both properties is required. Is also required.

[0004]

SUMMARY OF THE INVENTION The object of the present invention is to
(A) The tensile elastic modulus is small, its temperature dependence is extremely small in the low temperature region, and (b) when it is used as a coating material for an optical fiber (glass fiber),
A liquid curable resin composition that gives a cured product, in which the cured film has appropriate adhesion to glass, and the releasability is good to the extent that no residue remains on the glass when the film is peeled off. Is to provide.

[0005]

According to the present invention, [I] (A) (a) the following formulas (1) and (2)

Embedded image A urethane (meth) acrylate obtained by reacting a diol compound having a structure represented by: (b) a diisocyanate compound and (c) a hydroxyl group-containing (meth) acrylate compound, and (B) a homopolymer having a glass transition temperature of less than 0 ° C. (II) containing a (meth) acrylate compound and a (C) polymerization initiator and having [II] tensile elastic moduli measured at 23 ° C. and −40 ° C. of xkg / mm ² and ykg / mm ² , respectively: Formulas (I) and (II)

[Equation 2] A liquid curable resin composition, which is characterized by giving a cured product satisfying the above conditions, is provided to achieve the above-mentioned object of the present invention.

Hereinafter, the present invention will be described in detail, which will make clear the objects, configurations, effects and advantages of the present invention.

The urethane (meth) acrylate constituting the composition of the present invention is a diol compound (a) having a structure represented by the above formulas (1) and (2) (hereinafter referred to as "diol compound (a)"). , A diisocyanate compound (b) and a hydroxyl group-containing (meth) acrylate compound (hereinafter referred to as “(meth) acrylate compound (c)”).

The structure represented by the above formula (1) contained in the diol compound (a) is preferably 2 to 50% by weight, more preferably 10 to 50% by weight in the diol compound (a).
40% by weight is present. When the unit represented by the formula (1) is present in the diol compound (a) in the above range, the cured product of the composition of the present invention has a preferable balance in oil resistance and water resistance.

The structure represented by the formula (2) is preferably present in the diol compound (a) in an amount of 20 to 98% by weight, more preferably 60 to 90% by weight.

The diol compound (a) has, for example, the following formula (3-) in addition to the structures represented by the formulas (1) and (2).
1) to (3-6)

[0011]

Embedded image

The structure represented by can be included within a range not hindering the achievement of the object of the present invention. The content of these structures is usually 12% by weight or less in the diol compound (a).

The number average molecular weight of the diol compound (a) is
From the viewpoint of appropriately maintaining the coatability when applying the composition of the present invention to an optical fiber and the Young's modulus of a cured product of the composition, it is preferably 200 to 10,000, and more preferably 1,000. ~ 5,000.

The diol compound (a) can be produced, for example, by ring-opening copolymerization of ethylene oxide and 1,2-butene oxide. The ring-opening copolymerization may be either random copolymerization or block copolymerization, but random copolymerization is preferred.

When obtaining urethane (meth) acrylate,
A diol compound other than the diol compound (a) can be used in combination. Examples of such a polyol compound include polyether diols, polyester diols, polycarbonate diols, polycaprolactone diols, and other diols which do not have the structures represented by the above formulas (1) and (2) as constituent units.

Examples of the polyether diol include polyethylene glycol, 1,2-polypropylene glycol, polytetramethylene glycol, 1,2-polybutylene glycol, polyisobutylene glycol,
Examples thereof include ethylene oxide-tetrahydrofuran copolymer and methyltetrahydrofuran-tetrahydrofuran copolymer.

Examples of the polyester diol include ethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, tetramethylene glycol, polytetramethylene glycol,
1,6-hexanediol, neopentyl glycol,
1,4-cyclohexanedimethanol, 3-methyl-1,
5-pentanediol, 1,9-nonanediol, 2-
Examples include polyester polyols obtained by reacting polyhydric alcohols such as methyl-1,8-octanediol with polybasic acids such as phthalic acid, isophthalic acid, terephthalic acid, maleic acid, fumaric acid, adipic acid, sebacic acid. To be As a commercial item, Paul P-2010, 301
0, 4010, 5010, F-1010, 2010, 3
010, PMIPA-2000, PKA-A, MPD /
IPA, P-2011, MPD / TPA, L-201
0, 3010, A-1010, 1510, 2010, P
NA-2000, PNOA-1010, -2010 etc. (made by Kuraray Co., Ltd.) are mentioned.

As the polycaprolactone diol, for example, ε-caprolactone and ethylene glycol, polyethylene glycol, propylene glycol,
Divalent polypropylene glycol, tetramethylene glycol, polytetramethylene glycol, 1,2-polybutylene glycol, 1,6-hexanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, 1,4-butanediol, etc. Polycaprolactone diol obtained by reacting with a diol, and commercially available products include Praxel 205 and 205A manufactured by Daicel Corporation.
L, 212, 212AL, 220, 220AL and the like.

Other diols include, for example, ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, and diamine. Examples include dimethylolated products of cyclopentadiene, tricyclodecane dimethanol, hydroxy-terminated polybutadiene, hydroxy-terminated hydrogenated polybutadiene, polydimethylsiloxane terminal diol compounds, and polydimethylsiloxane carbitol-modified diols. These diols may be used alone or in combination of two or more.

The diol compounds other than these diol compounds (a) have a number average molecular weight of usually 200 to
It is 10,000, preferably 200 to 5,000. The amount of the diol compound other than the diol compound (a) used is 20% by weight or less based on the generated urethane (meth) acrylate.

As the diisocyanate compound (b) used to obtain urethane (meth) acrylate,
For example, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, 1,5-
Naatalenedisocyanate, m-phenylenediisocyanate, p-phenylenediisocyanate, 3,3'-
Dimethyl-4,4'-diphenylmethane diisocyanate,
4,4'-diphenylmethane diisocyanate, 3,3'-
Dimethylphenylene diisocyanate, 4,4'-biphenylene diisocyanate, 1,6-hexane diisocyanate, isophorone diisocyanate, methylenebis (4-cyclohexylisocyanate), 2,2,4-trimethylhexamethylene diisocyanate, 1,4-hexamethylene diisocyanate, Bis (2-isocyanatoethyl) fumarate, 6-isopropyl-1,3-
Examples thereof include phenyl diisocyanate, 4-diphenylpropane diisocyanate and lysine diisocyanate. These diisocyanates may be used alone or in combination of two or more.

Examples of the (meth) acrylate compound (c) include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate and 2
-Hydroxybutyl (meth) acrylate, 2-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, trimethylolethane di (meth) acrylate,
Pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, the following general formula (4)

[0023]

[Chemical 4]

(In the formula (4), R ₁ represents a hydrogen atom or a methyl group, and n represents an integer of 1 to 15, preferably an integer of 1 to 4) (meth) acrylate or alkylglycidyl Examples thereof include compounds obtained by addition reaction of a glycidyl group-containing compound such as ether, allyl glycidyl ether, and glycidyl (meth) acrylate with (meth) acrylic acid. These (meth) acrylate compounds (c) may be used alone or in combination of two or more. The (meth) acrylate compound (c)
Of which, 2-hydroxyethyl (meth) acrylate,
2-hydroxypropyl (meth) acrylate and the like are preferable.

The urethane (meth) acrylate used in the composition of the present invention is synthesized by the above-mentioned diol compound (a), polyisocyanate compound (b), (meth) acrylate compound (c) and, if necessary, diol compound. This can be achieved by reacting a diol compound other than (a). Specifically, it is carried out by reacting the isocyanate group of the polyisocyanate compound (b) with the hydroxyl groups of the diol compound (a) and another diol compound and the hydroxyl group of the (meth) acrylate compound (c). This reaction can be performed, for example, by the following method. a. diol compound (a) and other diol compounds,
Method in which the polyisocyanate compound (b) and the (meth) acrylate compound (c) are charged at once and reacted b. The diol compound (a) and another diol compound and the polyisocyanate compound (b) are reacted, and then (meth) ) Method of reacting acrylate compound (c) c. Method of reacting polyisocyanate compound (b) with (meth) acrylate compound (c), followed by reaction of diol compound (a) and other diol compound d. Poly The isocyanate compound (b) is reacted with a part of the (meth) acrylate compound (c), and then 20 to 8 of all the diol compounds (a) and other diol compounds are reacted.
Method of reacting 0% by weight, then reacting the remaining diol compound (a), and finally reacting the remaining (meth) acrylate compound (c)

The proportion of each of the diol compound (a), the polyisocyanate compound (b) and the hydroxyl group-containing (meth) acrylate compound (c) used is such that the hydroxyl group 1 contained in the diol compound (a) and the other diol compound is 1 It is preferable that the isocyanate group contained in the polyisocyanate compound (b) is 1.1 to 3 equivalents and the hydroxyl group of the (meth) acrylate compound (c) is 0.1 to 1.5 equivalents based on the equivalent amount. .

When a higher adhesion to glass is desired, a silane having a functional group capable of reacting a part of the (meth) acrylate compound (c) with an isocyanate during the above-mentioned reaction. It can be used by replacing it with a coupling agent. As the silane coupling agent used for such a purpose, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane,
Examples include γ-mercaptopropyltrimethoxysilane and γ-mercaptopropyltriethoxysilane. These silane coupling agents are preferably used in an amount such that the amount of the functional group capable of reacting with isocyanate is 0.05 to 0.3 equivalent based on 1 equivalent of the hydroxyl group of the (meth) acrylate compound (c). , And more preferably 0.05 to 0.1
It is used in an amount to give 5 equivalents.

In the above reaction, copper naphthenate, cobalt naphthenate, zinc naphthenate, di-n-butyltin laurate, triethylamine, triethylenediamine 2
A urethanization catalyst such as methyltriethylenediamine may be used in an amount of 0.01 to 1 part by weight based on 100 parts by weight of the total amount of the reactants. The reaction is preferably carried out at 10 to 90 ° C, particularly 30 to 80 ° C.

Urethane (meta) thus obtained
The preferred number average molecular weight of the acrylate is 1,000 to 20,000 from the viewpoint of keeping the tensile modulus of the obtained cured product low and keeping the viscosity of the composition of the present invention at an appropriate level.
And particularly preferably 2,000 to 15,000.

Urethane (meta) thus obtained
The blending ratio of the acrylate in the composition of the present invention is preferably 15 to 70% by weight for the purpose of setting the elongation at break of the cured product and the viscosity of the composition of the present invention in an appropriate range, but coating at the time of coating the optical fiber. Properties, flexibility of the coating material after curing, and better maintenance of long-term reliability, etc. 2
It is particularly preferable to set it to 0 to 60% by weight.

Another component constituting the composition of the present invention, a (meth) acrylate compound whose homopolymer has a glass transition temperature of less than 0 ° C. (hereinafter referred to as "(meth) acrylate compound (d)") As, for example, isobutyl acrylate, tridecyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, trioctyl acrylate, 2-methoxyethyl acrylate, 3-methoxybutyl acrylate, phenoxyethyl acrylate, phenol polyethylene glycol acrylate, nonylphenol polyethylene glycol acrylate, nonylphenol. Polypropylene glycol acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, tetrahydrofurfuryl acrylate DOO, 2-acryloyloxyethyl succinic acid and the like.

As a preferred (meth) acrylate compound (d), a high molecular weight monoalcohol obtained by subjecting a cyclic ether compound to ring-opening polymerization by, for example, ionic polymerization and sealing the active end with alcohols such as methanol A (meth) acrylic ester containing a compound as an alcohol component can be mentioned.

Preferred examples of the cyclic ether compound include those having 2 to 5 carbon atoms such as ethylene oxide, propylene oxide, butene oxide, tetrahydrofuran and 3-methyltetrahydrofuran. These may be used alone or in combination of two or more. Examples of the alcohol for blocking the active end include alcohols having 1 to 12 carbon atoms such as methanol, ethanol, propyl alcohol and butanol.

The polystyrene equivalent weight average molecular weight of the high molecular weight monoalcohol compound thus obtained is
It is 200 to 10,000, preferably 500 to 5,000. When the molecular weight is in the above range, the elastic modulus of the cured product of the composition of the present invention is kept small, and the handleability of the composition and the coating property on an optical fiber are improved.

Among the (meth) acrylate compounds (d), commercially available products include AIB, LA, 2-MTA, VISCOAT # 150, # 158, # 192 (all manufactured by Osaka Organic Chemical Co., Ltd.), NP-4, NP-8EA, LA, PO-
A, P-200A, HOA-MS (above, Kyoeisha Chemical Co., Ltd. product), M101, M113, M114, M117.
(These are manufactured by Toagosei Chemical Industry Co., Ltd.), KAYARAD
TC110S (Nippon Kayaku Co., Ltd.), M-3000-
20A, M-3000-21A (Daiichi Kogyo Seiyaku Co., Ltd.)
Manufactured) and the like.

Two or more kinds of the (meth) acrylate compound (d) described in detail above can be used in combination. Preferred combinations include lauryl acrylate and nonylphenol polyethylene glycol acrylate, and the number average molecular weight of polyethylene glycol chains is 40.
-300 nonylphenol polyethylene glycol acrylate and polyethylene glycol chain number average molecular weight 300-1,000 nonylphenol polyethylene glycol acrylate, number average molecular weight 500-5,
Copolymerization of ethylene oxide and butene oxide of 000, an acrylic ester containing lauryl acrylate as an alcohol component and a number average molecular weight of 50
It is a combination of 0 to 5,000 copolymers of ethylene oxide and butene oxide, an acrylic ester containing a monoalcohol as an alcohol component, and nonylphenol polyethylene glycol acrylate. These combinations can not only keep the Young's modulus of the cured product at room temperature low, but also suppress the increase of Young's modulus at low temperatures.

The (meth) acrylate compound (d) is preferably present in the resin composition in an amount of 10 to 70% by weight,
More preferably, it is present at 20-60% by weight. The presence of the above-mentioned amount of the (meth) acrylate compound (d) maintains the tensile elastic modulus at room temperature and the tensile elastic modulus at low temperature of the cured product at a low level, and the residual uncured product is small, resulting in long-term reliability. It gives favorable results in terms of sex. In addition, a suitable peeling property as well as a suitable adhesion property can be obtained, and in particular, it is substantially suppressed that the residue remains on the glass at the time of peeling from the glass.

If desired, the composition of the present invention may also contain a polymerizable diluent which is not included in the (meth) acrylate compound (d). Examples of the polymerizable diluent include compounds that are liquid or solid at room temperature and have at least one (meth) acryloyl group or vinyl group in the molecule. The compound having a (meth) acryloyl group or a vinyl group includes a monofunctional compound having one (meth) acryloyl group and a polyfunctional compound having a plurality of such groups, and any compound can be used.
Particularly, a (meth) acryloyl group or a vinyl group is used as 1
It is preferable to use a monofunctional compound having an individual number.

As the monofunctional compound having one (meth) acryloyl group, for example, t-butyl (meth) acrylate, stearyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate,
Butoxyethyl (meth) acrylate, ethoxydiethylene glycol (meth) acrylate, cyclohexyl (meth) acrylate, dicyclopentadienyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, tricyclodeca Nyl (meth) acrylate, isobornyl (meth) acrylate, bornyl (meth) acrylate, diacetone (meth) acrylamide, isobutoxymethyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, t-octyl (meth) acrylamide, Examples thereof include dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, and 7-amino-3,7-dimethyloctyl (meth) acrylate. As a commercial product, Aronix M
111, M5600, M5700 (above, manufactured by Toagosei Chemical Industry Co., Ltd.), KAYARAD R629, R644
(Nippon Kayaku Co., Ltd.), Viscoat # 155, #
3700, IBXA (above, manufactured by Osaka Organic Chemical Co., Ltd.) and the like.

Examples of the polyfunctional compound having two or more (meth) acryloyl groups include trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, ethylene glycol di (meth) acrylate and tetraethylene. Glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol (meth) acrylate, trimethylolpropane trioxyethyl (meth) acrylate , Tris (2-hydroxyethyl) isocyanurate tri (meth) acrylate, tris (2-hydroxyethyl) isocyanurate di (meth) acrylate, tricyclodecane dimethanol di (meth) acrylate, bisphine The diglycidyl ether of Nord A (meth) epoxy obtained by adding acrylate (meth) acrylate. Commercially available products include Upimer UV, SA1002, SA2007 (all manufactured by Mitsubishi Petrochemical Co., Ltd.), Viscoat # 700 (manufactured by Osaka Organic Chemical Co., Ltd.), KAYARAD R-604, DP.
CA-20, 30, 60, 120, HX-620, D-
310, 330 (all manufactured by Nippon Kayaku Co., Ltd.), Aronix M-210, 215, 315, 325 (all manufactured by Toagosei Chemical Industry Co., Ltd.) and the like.

The molecular weight of these compounds having a (meth) acryloyl group is usually in the range of about 200 to 3,000.

Examples of the compound having a vinyl group include N-vinylpyrrolidone, N-vinylcaprolactam, hydroxybutyl vinyl ether, lauryl vinyl ether, cetyl vinyl ether, 2-ethylhexyl vinyl ether and triethylene glycol divinyl ether. Among them, N-vinylpyrrolidone and N-vinylcaprolactam are preferable compounds for improving the adhesion of the cured product of the composition of the present invention and the curability of the composition.

These polymerizable diluents are preferably present in the composition according to the invention in an amount of 0 to 40% by weight, in particular 1 to 20% by weight. The presence of excess increases the tensile modulus at low temperature of the cured product, and increases the transmission loss when coated on an optical fiber.

The composition of the present invention is cured by heat and / or radiation. Here, the radiation means infrared rays, visible rays, ultraviolet rays, X-rays, electron beams, α rays, β rays, γ rays and the like.

When the composition of the present invention is heat-cured, a usual radical polymerization initiator can be used. Examples of the radical polymerization initiator include peroxides and azo compounds, and specific examples thereof include benzoyl peroxide, t-butyl-oxybenzoate, and azobisisobutyronitrile.

When the composition of the present invention is cured with visible light, ultraviolet rays, etc., a photopolymerization initiator is used as a polymerization initiator and, if necessary, a photosensitizer is further used. Examples of such a photopolymerization initiator include 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-2-phenylacetophenone, xanthone, fluorenone, benzaldehyde, fluorene, anthraquinone, triphenylamine, carbazole, and 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-phenylpropan-1-one, thioxanthone, diethylthioxanthone, 2-isopropylthioxanthone, 2-chlorothioxanthone, 2-methyl-1- [4
Examples include-(methylthio) phenyl] -2-morpholino-propan-1-one, 2,4,6-trimethylbenzoyldiphenylphosphine oxide and the like. Further, as commercially available products, IRUGACURE 184, 651, 50
0, 907, CGI369, CGI-1700 (above,
Ciba-Geigy Co., Ltd., Lucirine LR872
8 (manufactured by BASF Corp.), Darocure 1116,
1173 (Merck KK), Yubekuriru P36
(Manufactured by UCB Corp.) and the like. These photopolymerization initiators are preferably blended in the composition of the present invention in an amount of 0.1 to 10% by weight.

Further, as the photosensitizer, triethylamine, diethylamine, N-methyldiethanolamine, ethanolamine, 4-dimethylaminobenzoic acid,
There are ethyl 4-dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate and the like, and commercially available products include Yubecryl P102, 103, 104 and 105 (above, UCB
(Manufactured by Co., Ltd.) and the like. These photosensitizers are preferably incorporated in the composition of the present invention in an amount of 5% by weight or less.

Further, as additives to be added as required, for example, antioxidants, ultraviolet absorbers, light stabilizers,
Silane coupling agent, anti-aging agent, thermal polymerization inhibitor, leveling agent, surfactant, storage stabilizer, softener, lubricant,
Solvents, fillers, colorants, wettability improvers, coating surface improvers and the like. Commercially available antioxidants include Irganox
1010, 1035, 1076, 1222 (these are manufactured by Ciba Geigy Co., Ltd.) and the like. Commercially available ultraviolet absorbers include Tinuvin P, 234, 320,
326, 327, 328, 213 (all manufactured by Ciba Geigy), Sumisorb 110, 130, 14
0, 220, 250, 300, 320, 340, 35
0, 400 (above, manufactured by Sumitomo Chemical Co., Ltd.) and the like. Commercially available light stabilizers include Tinuvin 2
92, 144, 622LD (above, Ciba Geigy Co., Ltd.)
Manufactured), Sanol LS-770, 765, 292, 262
6, 1114, 744 (above, Sankyo Kasei Kogyo Co., Ltd.)
Etc. As the silane coupling agent, γ-
Aminopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, and the commercially available products include
SH6062, SZ6030 (all manufactured by Toray Dow Corning Silicone Co., Ltd.), KBE903, KBM8
03 (above, manufactured by Shin-Etsu Silicone Co., Ltd.) and the like. Antigen is commercially available as Antigen
W, S, P, 3C, 6C, RD-G, FR, AW, GA
-80 (above, Sumitomo Chemical Co., Ltd. product) etc. are mentioned.

In the composition of the present invention, other additives such as epoxy resin, polyamide, polyamide-imide,
Polyurethane, polybutadiene, chloroprene, polyether, polyester, pentadiene derivative, styrene / butadiene / styrene block copolymer, styrene /
Ethylene / butene / styrene block copolymer, styrene / isoprene / styrene block copolymer, petroleum resin, xylene resin, ketone resin, fluorine-based oligomer,
Polymers or oligomers such as silicone-based oligomers and polysulfide-based oligomers can also be blended.

The composition of the present invention can be produced by mixing the above-mentioned components by a conventional method. The viscosity of the composition of the present invention thus prepared is usually 100 to 20,0.
00 cps / 25 ° C, preferably 1,500 to 15,000
It is 0 cps / 25 ° C.

The composition of the present invention is then cured at 23 ° C. and -40 ° C. by curing it with heat or radiation.
Tensile elastic modulus when measured at ℃, xkg / mm ² ,
When ykg / mm ² , the above formulas (I) and (I
It provides a cured product that satisfies I).

When the composition of the present invention is used as a primary coating material for an optical fiber, the cured product has a tensile elastic modulus x kg / mm ² of 0.2 kg / mm ² or less when measured at 23 ° C. One of the causes of the increase in the transmission loss of the optical fiber will be substantially eliminated. And 23
The ratio x / y of the tensile elastic modulus x kg / mm ² at ℃ to the tensile elastic modulus ykg / mm ² at -40 ° C is 1/10 or more, and the temperature dependence of the tensile elastic modulus is small in the low temperature region, so that Also in the above, one of the causes of the increase of the transmission loss of the optical fiber is substantially removed.

Particularly preferred tensile elastic modulus at 23 ° C. × kg
/ Mm ² is 0.02 to 0.18 kg / mm ² , and x
The ratio (x / y) of kg / mm ² to tensile modulus ykg / mm ² at −40 ° C. is preferably 1/5 or more.

With respect to the cured product of the composition of the present invention, in order to make the tensile modulus of elasticity satisfy the above formulas (I) and (II), the diol compound (a) used for preparing the urethane (meth) acrylate is used. ), Polyisocyanate compound (b), (meth) acrylate compound (c) and other optional components described above, the type and amount of (meth) acrylate compound (d), and the composition of the present invention. It is possible to experimentally know beforehand the relationship between the tensile elastic modulus of the cured product and the type and amount of other optional components used for the curing, the type and amount of the polymerization initiator, the curing temperature, the type of radiation, and the like. Therefore, based on this finding, the above formula (I)
It is possible to obtain a cured product that satisfies both (II) and (II).

[0055]

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

Urethane Acrylate Polymer Synthesis Example 1 In a reaction vessel equipped with a stirrer, 5.95 parts of tolylene diisocyanate and a number average molecular weight of 4,000, a copolymer diol of ethylene oxide and butene oxide (the above formula (1) The content of the structure represented by formula = 30% by weight, the content of the structure represented by formula (2) = 70% by weight) 91.30
Parts, and 2,6-di-, which is a polymerization inhibitor as an additive
0.02 part of t-butyl-p-cresol was charged. While stirring these, ice cooling was carried out until the liquid temperature became 10 ° C or lower. When the liquid temperature becomes 10 ° C or lower, 0.08 part of dibutyltin dilaurate is added to adjust the liquid temperature to 20 to 30.
The mixture was stirred for 2 hours while controlling at ℃. Then, 2.65 parts of hydroxyethyl acrylate was added thereto, and the liquid temperature was 5
Stirring was continued at 0 to 60 ° C. for 4 hours, and the reaction was terminated when the residual isocyanate content was 0.1% by weight or less. The urethane acrylate obtained by this method is UA-1
And

Urethane Acrylate Synthesis Example 2 A reaction vessel equipped with a stirrer was charged with 5.95 parts of tolylene diisocyanate and a number average molecular weight of 4,000, a copolymerized diol of polyethylene oxide and butene oxide (shown by the above formula (1)). Content of structure = 20% by weight, content of structure represented by the formula (2) = 80% by weight) 91.30
Parts, and 2,6-di-, which is a polymerization inhibitor as an additive
0.02 part of t-butyl-p-cresol was charged. Then, these were stirred and ice-cooled until the liquid temperature became 10 ° C. or lower. When the liquid temperature becomes 10 ° C or lower, 0.08 part of dibutyltin dilaurate is added to adjust the liquid temperature to 20 to 3
The mixture was stirred for 2 hours while controlling at 0 ° C. Then, 2.65 parts of hydroxyethyl acrylate was added thereto, stirring was continued at a liquid temperature of 50 to 60 ° C. for 4 hours, and the reaction was terminated when the residual isocyanate was 0.1% by weight or less.
The urethane acrylate obtained by this method is UA-
Set to 2.

Urethane Acrylate Synthesis Example 3 In a reaction vessel equipped with a stirrer, 5.95 parts of tolylene diisocyanate and a number average molecular weight of 4,000, a copolymer diol of ethylene oxide and butene oxide (shown by the above formula (1)) Content of the structure represented by formula (2) = 30% by weight, content of the structure represented by the formula (2) = 70% by weight) 91.30
Parts, and 2,6-di-, which is a polymerization inhibitor as an additive
0.02 part of t-butyl-p-cresol was charged. Then, these were stirred and ice-cooled until the liquid temperature became 10 ° C. or lower. When the liquid temperature becomes 10 ° C or lower, 0.08 part of dibutyltin dilaurate is added to adjust the liquid temperature to 20 to 30.
The mixture was stirred for 2 hours while controlling at ℃. And there γ-
0.5 parts of mercaptopropyltrimethoxysilane and 2.65 parts of hydroxyethyl acrylate were added, and stirring was continued for 4 hours at a liquid temperature of 50 to 60 ° C. when the residual isocyanate was 0.1% by weight or less. The reaction was completed.
The urethane acrylate obtained by this method is UA-
Set to 3.

Examples 1 to 6 and Comparative Examples 1 and 2 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. Then, the uniformly stirred composition was used in the following test.

In Table 1, nonylphenol polyethylene (n = 4) glycol acrylate, nonylphenol polyethylene (n = 7) glycol acrylate, M-3000-21A, Lucirin, CGI.
-1700 is as follows.

[0061]

Embedded image

[0062]

[Table 1]

The compositions obtained above were tested for tensile modulus, adhesion and releasability as follows.

(1) Tensile Elastic Modulus Test (i) Preparation of Tensile Elastic Modulus Specimen: The composition was applied onto a glass plate using an applicator bar having a thickness of 150 microns, and 1.0 J / cm under air. ^It was irradiated with ultraviolet rays of ² to obtain a cured film. Then, peel off the cured film from the glass plate,
A test piece was prepared by preparing the state for 24 hours at 23 ° C. and 50% relative humidity. (Ii) Measurement of tensile elastic modulus (xkg / mm ² ) at 23 ° C: The tensile elastic modulus at 23 ° C was measured according to JIS K7113. However, the pulling speed is 1 mm / min
The tensile modulus was calculated from the tensile stress at a strain of 2.5%. (Iii) Tensile elastic modulus at -40 ° C (ykg / mm ² ) The tensile elastic modulus at -40 ° C was measured according to JIS K7113. However, the tensile speed was 1 mm / min, and the tensile modulus was calculated from the tensile stress at a strain of 2.5%. The measurement results above show that the tensile modulus at −23 ° C. and −40
Table 2 also shows the ratio (x / y) to the tensile elastic modulus at ° C.

(2) Adhesion test (i) Preparation of adhesion test piece: A liquid composition was applied onto a quartz plate using an applicator bar having a thickness of 150 μm,
It was irradiated with ultraviolet rays of 0.1 J / cm ^{2 in} a nitrogen atmosphere to form a cured film, which was cut into 1 cm width to give a test piece. (Ii) Measurement of adhesion force The cured film on the quartz plate is 50 mm /
The cured film was peeled off at a speed of min, and the adhesive force (g / cm) to the 1 cm width of the cured film was measured.

(3) Peelability test (i) Preparation of peelability test piece: A liquid composition was applied onto a quartz plate using an applicator bar having a thickness of 150 microns,
It was irradiated with 0.1 J / cm ² of ultraviolet rays under air to obtain a cured film. (Ii) Peelability measurement: Peeling off the cured film from the quartz plate in the opposite direction at 180 ° at a speed of 50 mm / min, and visually observing and touching with a finger whether or not the residue remains on the quartz plate. It was judged by. When the residue was not confirmed on the glass plate by any method, it was marked with ◯, and when the residue was confirmed by any method, it was marked with x.

[0067]

[Table 2]

[0068]

The liquid curable resin composition of the present invention is
(A) The tensile elastic modulus is small, its temperature dependence is extremely small in the low temperature region, and (b) when it is used as a coating material for an optical fiber (glass fiber),
The cured product has a suitable adhesion to the glass, and has a good releasability to the extent that no residue remains on the glass when the film is peeled off. Therefore, the composition of the present invention is a material suitable as a primary coating material for an optical fiber, which is required to have a low elastic modulus and a low temperature dependency in a wide temperature range.

Preferred embodiments of the liquid curable resin composition of the present invention detailed above will be described below. 1. The (meth) acrylate compound (d) has a carbon number of 2 to
It is a (meth) acrylic ester having an alcohol component of a monoalcohol having a number average molecular weight of 200 to 10,000 obtained by ionic ring-opening polymerization of a cyclic ether of 5 and sealing an active end with an alcohol having 1 to 12 carbon atoms. Liquid curable resin composition. 2. The (meth) acrylate compound (d) is a combination of lauryl acrylate and nonylphenol polyethylene glycol acrylate, the number average molecular weight of the polyethylene glycol chain is 40 to 300, and the number average molecular weight of the polyethylene glycol chain is 300 to 300. Combination with 1,000 nonylphenol polyethylene glycol acrylate, Copolymerization of ethylene oxide and butene oxide having a number average molecular weight of 500 to 5,000, a combination of acrylic ester and lauryl acrylate having an alcohol component of monoalcohol and number average molecular weight Is 500 to 5,
000, a liquid curable resin composition which is a combination of an acrylic ester containing a copolymerized monoalcohol of ethylene oxide and butene oxide as an alcohol component and nonylphenol polyethylene glycol acrylate.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Mitsufumi Suwa 2-11-24 Tsukiji, Chuo-ku, Tokyo Within Nippon Synthetic Rubber Co., Ltd. (72) Inventor Komiya Zen 2-11-24 Tsukiji, Chuo-ku, Tokyo Within Japan Synthetic Rubber Co., Ltd. (72) Inventor Takashi Ukaji 2-11-24 Tsukiji, Chuo-ku, Tokyo Within Japan Synthetic Rubber Co., Ltd.

Claims (1)

[Claims] 1. [I] (A) (a) The following formulas (1) and (2): A urethane (meth) obtained by reacting a diol compound having a structure represented by: (b) a diisocyanate compound, and (c) a hydroxyl group-containing (meth) acrylate compound.
Acrylate, (B) a homopolymer having a glass transition temperature of less than 0 ° C. (meth) acrylate compound, and (C) a polymerization initiator, and [II] a tensile elastic modulus measured at 23 ° C. and −40 ° C. each following formula when the ^{xkg / mm 2, ykg / mm} 2 (I) and (II) [number 1] A liquid curable resin composition, which is characterized by giving a cured product satisfying the above conditions.