JPS61291611A - Resin composition and coating agent therefrom - Google Patents

Abstract

PURPOSE:To obtain a resin composition capable of giving coating film of low water absorptivity and no variation in its physical properties over a wide range of temperatures, suitable for coating on glass fiber for use in light transmission, by blending a di(meth) acrylate of carbonatediol, polyureshane (meth) acrylate, etc. CONSTITUTION:The objective resin composition can be obtained by blending, (A) pre. 10-40wt% of a di(meth) acrylate of carbonatediol (with an average molecular weight 500-3,000), (B) pref. 40-60wt% of a polyurethane methacrylate, (C) pref. 30-60wt% of a monothylenic unsaturated monomer [e.g., (meth)acrylate of tetrahydrofurfuryl alcohol epsilon-caprolactone adduct] and, if needed, (D) <=10wt% of a photopolymerization initiator (e.g., benzylmethyl ketal).

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a resin composition containing di(meth)acrylate of carbonate diol and a coating agent for optical glass fibers for light transmission.

(Prior Art) Since optical fibers have excellent information transmission performance and are relatively immune to external interference, their use has increased significantly in recent years, especially in the communications field.

Optical fibers are commonly made of glass because they are used in the telecommunications field. However, glass fibers are inherently brittle and are easily broken due to chemical agitation by water vapor, making them difficult to handle. Therefore, conventionally, optical glass fibers are
The surface is coated with resin. Conventionally, epoxy resins, urethane resins, etc. have been used as such resin coating materials, but they take a long time to harden, resulting in poor productivity.They also lack flexibility, which impairs transmission characteristics due to lateral pressure. There are drawbacks. Recently, ultraviolet curable compositions containing urethane acrylate have been actively studied in order to improve the above-mentioned drawbacks, and ultraviolet curable compositions for optical glass fibers and methods for forming such coatings have been published, for example, in Japanese Patent Application Laid-Open No.
No. 223,638 and Japanese Unexamined Patent Publication No. 59-170154.

(Problems to be Solved by the Invention) Currently used ultraviolet curable compositions have the advantage of fast curing speed and the ability to easily and accurately obtain desired properties, but due to their high water absorption, they cannot be stained by water. The fiber is easily damaged.

Furthermore, it has the disadvantage that when it is cured and the temperature changes periodically from room temperature to -60°C to +80°C, the physical properties change significantly, causing an increase in transmission loss, which is undesirable.

(Means for Solving the Problems) In order to solve the above problems, the present inventors have conducted intensive research and found that the curing speed is fast, the resin coating obtained by curing is flexible, and the water absorption rate is low. There is little change in film properties over a wide temperature range from high to low temperatures, and the glass transition point is low.
We have discovered a new resin composition suitable for coating optical glass fibers for light transmission, and completed the present invention.

That is, the present invention provides (1) carbonate diol (average molecular weight 500-3
000) di(meth)acrylate (A), polyurethane (meth)acrylate (B), a monoethylenically unsaturated monomer (q), and a photopolymerization initiator (D) as an optional component. .

(2) Carbonate diol (average molecular weight 500~
A coating agent for optical glass fibers, characterized in that it contains di(meth)acrylate (3) of 3000), polyurethane(meth)acrylate), a monoethylenically unsaturated monomer (Q), and a photopolymerization initiator (DJ).

It is related to.

Carbonate diol used in the present invention (average molecular weight 50
0 to 3000) di(meth)acrylate (hereinafter referred to as carbonate diol di(meth)acrylate) can be obtained by reacting carbonate diol and (meth)acrylic acid. The specific manufacturing method of carbonate diol di(meth)acrylate is publicly known,
For example: The amount of meth)acrylic acid per 0.5 mol of carbonate diol is preferably 1.0 to 2.
0 mol, particularly preferably 1.0 to 1.5 mol, an esterification catalyst (e.g. p-toluenesulfonic acid, sulfuric acid, phenolic acid, etc.) and a polymerization inhibitor (e.g. methoquinone,
Phenothiazine, hydroquinone, etc.) are preferably added in an amount of 0.01 to 5% by weight based on (meth)acrylic acid, preferably heated to 70°C to 130°C, dehydrated, washed with alkali, and washed with water to remove low boiling point substances. Removal yields carbonate diol di(meth)acrylate. Carbonate diol as a raw material for producing carbonate diol di(meth)acrylate can be produced, for example, as follows. i.e. carbonate derivatives such as diphenyl carbonate, bis-
Chlorophenyl carbonate, dinaphthyl carbonate, phenyl-chlorophenyl carbonate, phenyl-chlorophenyl-carbonate, 2-tolyl-4-tolyl-
diaryl carbonate or dialkyl carbonate such as carbonate, dimethyl carbonate, diethyl carbonate, and diols, such as 1,6-hexanediol, neopentyl glycol, 1,4-butanediol, 1,8-octanediol, ■, 4-bis -(hydroxymethyl)-cyclohexane, 2-methylpropanediol, dipropylene glycol, dibutylene glycol or the above diol compound and oxalic acid, malonic acid,
It can be obtained by transesterification with polyester diol, which is a reaction product of dicarboxylic acids such as succinic acid, adipic acid, azelaic acid, and hexahydrophthalic acid.

It can also be produced by reacting phosgene with the diols mentioned above. The carbonate diol thus obtained is a monocarbonate diol having one carbonate structure in the molecule or a polycarbonate diol having two or more carbonate structures in the molecule, and can be easily obtained from the market. For example, Desmophen 2020E (manufactured by Sumitomo Bayer ■, average molecular weight 2000)
, DN-980 (manufactured by Nippon Polyurethane, average molecular weight 2
000), DN-981 (Japan Polyurethane ■Crack, average molecular [1000), DN-982 (Japan Polyurethane ■
DN-983 (Japan Polyurethane Polyurethane, average molecular weight 1000), and the like.

In particular, DN-982 and DN-983 are preferred as raw materials for carbonate diol di(meth)acrylate used in the present invention.

Further, in the present invention, carbonate diol diacrylate is more preferable than carbonate diol dimethacrylate.

In the resin composition and coating agent of the present invention (hereinafter referred to as composition), carbonate diol di(meth)acrylate is preferably used in an amount of 5 to 50% by weight, particularly 10 to 40% by weight. It is preferable to use it within the range of .

In the present invention, polyurethane (meth)acrylate is used, and its average molecular weight is usually 1,000 or more, preferably about 2,000 to 10,000. Such polyurethane (meth)acrylates include polyurethane (meth)acrylates of polyether polyols with ether groups in the molecule, polyurethane (meth)acrylates of polyester polyols with ester groups, or polyurethane (meth)acrylates with both ether groups and ester groups in the molecule. Examples include polyurethane (meth)acrylate containing polyurethane (meth)acrylate and polyurethane (meth)acrylate containing carbonate diol having a carbonate group. Examples of polyether polyols include polypropylene glycol, polyethylene glycol, polytetramethylene glycol, and 1,3-butylene glycol, 1,4-butylene glycol, 1,6-hexanediol, neopentyl glycol, cyclohexane dimetatool, 2. 2-bis(
A compound obtained by adding ethylene oxide or propylene oxide to 4-hydroxycyclohexyl)propane, bisphenol A, etc. can be used. Polyester polyol can be obtained by reacting an alcohol component and an acid component. For example, polypropylene glycol, 6-hexanediol, neopentyl glycol, cyclohexane dimetatool, 2,2-bis(
A compound in which ethylene oxide or propylene oxide is added to (4-hydroxycyclohexyl) propane, bisphenol A, etc. or a compound in which nibsilone caprolactone is added is used as the alcohol component, and as an acid component, adipic acid, sebacic acid, etc. Dibasic acids such as , azelaic acid, dodecanedicarboxylic acid, and their anhydrides can be used. A compound obtained by simultaneously reacting the above-mentioned alcohol component, acid component, and nibsilone caprolactone can also be used as the polyester polyol. Further, as the carbonate diol, those used as the raw materials for producing component A described above can be used. In order to obtain polyurethane (meth)acrylate (BJ) using these polyether polyols, polyester polyols, and carbonate diols, organic diisocyanate and polymeric edge monomers having hydroxyl I groups are substantially added to the hydroxyl groups of the polyol. Polyurethane (meth)acrylate (B) can be obtained by reacting until it contains no NCO groups. Typical examples of organic diisocyanates include aromatic diynes such as tolylene diisocyanate and 4,4-diphenylmethane diisocyanate. cyanate, isophorone diisocyanate), 4,4-dicyclohexylmethane diisocyanate and alicyclic diincyanates such as hexamethylene diisocyanate), 2,2'-)limethylhexamethylene diisocyanate, etc. In addition, as a polymerizable monomer having a hydroxyl group, β
- hydroxyl such as hydroxyethyl (meth)acrylate, β-hydroxy 7proyl (meth)'7v'+)late, β-hydroxylauryl (meth)acrylate, nibsilone caprolactone-β-hydroxyethyl (meth)acrylate adduct. (meth)acrylates having groups, etc.

The reaction between NGO groups and OH groups proceeds even without a catalyst, but for example, tertiary amines such as triethylamine,
Conventional catalysts such as organometallic compounds such as dibutyltin silaurylate and dibutyltin diacetate, or tin chlorides and the like may be used.

Particularly preferred polyurethane (meth)acrylate (f3
+ represents polyurethane acrylate of carbonate diol, and as the organic diisocyanate, inphorone diisocyanate and 4,4-dicyclohexylmethane diincyanate are particularly preferred.

The amount of polyurethane acrylate (B) used is preferably 20 to 70% by weight, particularly 40 to 60% by weight.
It is preferable that it is % by weight, and if too much is added, the viscosity will increase.
l-"if<, it becomes difficult to handle.

Monoethylic unsaturated monomer (Various monoacrylates or methacrylates can be used as Q, but
It is preferable to use a homopolymer with a glass transition temperature as low as possible. Specific examples include phenyloxy (or alkylphenyloxy) polyethoxy (meth)acrylate, phenyloxy (or alkylphenyloxy) polypropoxy (meth)acrylate , nonylphenyloxypolyethoxy (meth)acrylate, phenyloxy (or alkylphenyloxy) ethoxy (meth)acrylate, phenyloxy (or alkylphenyloxy) propoxy (meth)acrylate, ε-caprolactone adduct of tetrahydrofurfuryl alcohol (Meth)acrylate (Nippon Kayaku 1!!,
KAYARAD TC-11O8, KAYARAD
TC-120, etc.), ε-caprolactone-β-hydroxyethyl (meth)acrylate adducts (Daicel Chemical Industry, Plaxel FA-1, Plaxel FM-1, etc.), Carpitol acrylate, Patent application 1511/1982
Examples include (meth)acrylates of ε-caprolactone adducts of polyethoxy or polypropoxy compounds of phenol derivatives described in No. 79.

Among the monoethylenically unsaturated monomers (C1, particularly preferred are (meth)acrylates of ε-caprolactone adducts of tetrahydrofurfuryl alcohol (
Nippon Kayaku, KAYARAD TC-1108%KA
YARAD TC-120 etc.) and patent application 1986-151
ε- of polyethoxy or polypropoxy compounds of phenol derivatives having the following structural formula described in 179
The (meth)acrylate of caprolactone adduct is mentioned (
In the formula, 几1 is a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, R2 and R3 are each a hydrogen atom or a methyl group, and the average value of m is a number of 1 to 10,
The mean value of the mouth is a number from 1 to 10. ) This compound is obtained by reacting a compound obtained by adding ethylene oxide or propylene oxide to a phenol derivative such as phenol or nonylphenol, and (meth)acrylic acid with an ester catalyst such as para-toluenesulfonic acid. It can be obtained by reacting at a temperature of 70 to 130°C in the presence of a polymerization inhibitor such as hydroquinone.

The amount of monoethylenically unsaturated monomer C) used is preferably 20 to 70% by weight, particularly preferably 30 to 60% by weight, in the composition.

The photopolymerization initiator used in the present invention may be any known photopolymerization initiator, but it is required to have good storage stability after blending.

Examples of such photopolymerization initiators include benzoin alkyl ethers such as benzoin ethyl ether, benzoin isobutyl ether, and benzoin isopropyl ether, 2,2-jethoxyacetophenone, 4-phenoxy-2゜2-dichloroacetophenone, and the like. acetophenone, 2-hydroxy-2-methylpropiophenone, 4'-inpropyl-2-hydroxy-2-methylpropiophenone, 4'-dodecyl 2-hydroxy-2-methylpropiophenone, etc. Phenone type, benzyl dimethyl ketal, 1-hydroxycyclohexylphenyl ketone and anthraquinone type such as 2-ethylanthraquinone, 2-chloroanthraquinone,
Other examples include thioxanthone-based photopolymerization initiators. Particularly preferred are 1-hydroxycyclohexylphenyl ketone, benzyl dimethyl ketal, and the like. These photopolymerization initiators 0) may be one type,
Two or more types may be mixed and used in any ratio. The amount used is usually preferably 0 to 10% by weight of the resin composition, and particularly 0.1 to 10% by weight of the coating agent.
~5% by weight is preferred. The composition of the present invention may further contain polymerizable monomers, N-vinylpyrrolidone, polyethylene glycol di(meth)acrylate,
A portion of polypropylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, etc. may be added.

Further, if desired, a modifying resin and various additives may be added, and examples of the modifying resin include epoxy resin, polyurethane, polybutadiene, polyether, polyamideimide, silicone resin, and phenol resin. Examples of the additives include organosilicon compounds, surfactants, and polymerization inhibitors.

The resin composition of the present invention is useful for coating optical glass fibers, and can also be used as an adhesive for laminated glass, a fiber treatment agent, and the like.

When coating an optical glass fiber with the coating agent for optical glass fiber of the present invention, a die coating method is suitable as a coating method. The optical glass fiber can be drawn at a very high speed of 3 to 7 m/sec.

When coating an optical glass fiber, the thickness of the coating with the coating agent of the present invention is not particularly limited, but is usually 2.
It is preferably about 0 to 300μ.

The coating agent of the present invention is easily cured by ultraviolet irradiation. The coating agent of the present invention can be cured by ultraviolet irradiation using a conventional method. For example, ultraviolet rays may be irradiated using a low-pressure or high-pressure mercury lamp, a xenon lamp, or the like.

(Example) Hereinafter, the present invention will be specifically explained with reference to Examples. In addition,
Parts in the examples are parts by weight.

[Production example of carbonate diol di(meth)acrylate]

Production Example 1 Into a 21 reactor equipped with a stirrer, a temperature controller, a thermometer, and a condenser, carbonate diol (Nippon Polyurethane No., product name DN-983, OPI value 112.2 KOFI) was added.
/ g, melting point 5°C, average molecular weight approximately 1000) 700 parts,
121 parts of acrylic acid, 14 parts of p-toluenesulfonic acid,
1.0 part of hydroquinone, 560 parts of benzene, and 140 parts of cyclohexane are charged and heated, and the produced water is distilled and condensed together with the solvent, and only the water is removed from the system in a separator, and the solvent is returned to the reactor. Cooling occurred when 25.2 parts of water had been produced. The reaction temperature was 80-86°C. The reaction mixture was dissolved in 960 parts of benzene and 240 parts of cyclohexane.
After neutralizing with 205% caustic soda aqueous solution, 205% saline solution 50%
Wash 3 times with 0 parts. The solvent was distilled off under reduced pressure to obtain 690 parts of a pale yellow liquid. This material has the following properties.

Specific gravity (25℃) 1.1000 viscosity
Degree (25°G) 2100 cps Saponification value 414.4■KOH/g Acid value
0.01 rngKOH/g refractive index (2
08C) 1.4680 The results of high-resolution, nuclear magnetic resonance (NMR) measurement of the absorption frequency of the obtained product are shown below.

% Absorption frequency (Hz) 1 2603.515 2 2495.140 3 2333.984 4 1958.984 5 1933.593 6 1199.218 7 1166.015 8 1134.865 9 1015.625 1Q 966°79 6 11 962.890 12 935.546 13 511.718 14 490.234 15 429.687 16 382.812 East Absorption frequency (Hz) 17 369.140 18 0.000 Me. Using H', the coupled measurement of c13-H showed the final identification result of the C13 D couple. Among the above absorptions, l'h 6.7.8 indicates the absorption peak position of the solvent. %18 indicates the peak position of tetramethylsilane.

Production Example 2゜In the same reactor as Production Example 1, carbonate diol (Japan Polyurethane, DN-982, O) with a value of 56 r
rtgKOH/g, melting point 5°C, average molecular weight approximately 2000)
700 parts of acrylic acid, 61 parts of p-toluenesulfonic acid, 0.4 parts of hydroquinone, 560 parts of benzene, and 140 parts of cyclohexane, and the reaction was carried out in the same manner as in Production Example 1 until the amount of water produced was 12.6 parts. Ta. The reaction temperature is 8
The temperature was 1-86°C. The reaction mixture was dissolved in 1200 parts of benzene and 300 parts of cyclohexane, and neutralized, washed, and desolventized in the same manner as in Production Example 1 to obtain 654 parts of a pale yellow liquid.
I got the department. This material has the following properties.

Specific gravity (25°C) 1.1060 viscosity
Degree (25°C) 13750 cps Saponification value 415.7 rr@KOH/g Acid value 0.03 qKO/g Refractive index (20°C) 1.470O NMR measurement results Absorption frequency (Hz) 1 2607.421 2 2333.987 3 1960.937 4 1933.593 5 1195.312 6 1164.062 7 1130.859 8 1017.578 9 964.843 10 511, 71811
429.687 (Absorption frequency (Hz) 12 382.812 13 369.140 14 0,000 Among the above absorptions, the slow 5.6.7 is the absorption peak of the solvent (
Indicates Sli. 1.4 indicates the peak position of tetramethylsilane.

Production Example 3 Into the same reactor as Production Example 1, carbonate diol (Japan Polyurethane Co., Ltd., DN-983, (JH value 112.
2 mg KOH/g, melting point 5°C, average molecular weight approximately 100
0) 700 parts, 145 parts of methacrylic acid, 4.5 parts of sulfuric acid,
1.1 parts of hydroquinone and 700 parts of toluene were charged, and the reaction was carried out in the same manner as in Production Example 1 until the amount of produced water became 25.2 parts. The reaction temperature was 105-116°C. The reaction mixture was dissolved in 1000 parts of toluene, and in the same manner as in Production Example 1,
Neutralization, washing, and solvent removal were performed to obtain 723 parts of a pale yellow liquid.

This material has the following properties.

Specific gravity (25℃) 1.094.0 viscosity
Degrees (25°C) 1900 cps
Saponification value 400.0 ■KO) I/g acid
Value 0.02 ■KO) 1 part g
Refractive index (20°C) 1.468O NMR measurement results slow Absorption frequency (Hz) 1 2601.562 2 2509.765 3 2333.984 4 2052.734 5 1878.906 6 1201.171 7 1167.968 8 1136 .718 9 1015.625 10 968.750 11 962.890 12 933.593 13 509.765 14 429.687 Slow Absorption frequency (Hz) 15 382.812 16 369.140 17 273.437 18 0.0 00 above Among the absorptions, N16.7.8 indicates the absorption peak position of the solvent. 18 indicates the peak position of tetramethylsilane.

[Production example of polyurethane acrylate (Bl)] Production example 4
° Polypropylene glycol (molecular weight approximately 2000
．． 0) Monovalent 56.1) 253.1 parts, monovalent polyester polyol (Daicel Chemical Industry, Plaxel L-220AL, molecular weight approximately 2000.0), which is a reaction product of neopentyl glycol, adipic acid, and ε-caprolactone 57.5) 251.3 parts of isophorone diisocyanate and 84.7 parts of isophorone diisocyanate were charged, and after raising the temperature, the reaction was carried out at 75°C for 10 hours.Then, the reaction solution was cooled to 60°C, and ε-caprolactone-β-hydroxyethyl acrylate was added. (manufactured by Daicel Chemical Industries, Ltd., Plaxel FA-2) 91.4 parts,
0.3 part of methoquinone and 0.12 part of diloptyltin dilaurate were charged, and after raising the temperature, the reaction was carried out at 75 to 80°C. The product has the following properties.

Viscosity (60°C) ll0P refractive index (20
℃) 1.4721 Manufacturing Example 5゜Into the same reactor as Manufacturing Example 4, 500 parts of carbonate diol (Sumitomo Bayer ■, product name: Desukamifen 2020E, molecular weight approximately 2000, OLJ value 56), inphorone diisocyanate. ) 83.3 parts, and after raising the temperature, 1 at 75℃
The reaction mixture was reacted for 0 hours, and then the reaction solution was cooled to 60°C, and ε-caprolactone-β-hydroxyethyl acrylate adduct (Daicel Chemical Industries, Plaxel FA-2) was added at 90°C.
．． 3 parts of methoquinone, 0.3 part of methoquinone, and 0.1 part of di-n-butyltin dilaurate were added, and after raising the temperature, the reaction was carried out at 75 to 80°C. The product has the properties mentioned.

Viscosity (80°C) 675P refractive index (2
0°C) 1.4730 Production Example 6゜In the same reactor as Production Example 4, add polyester diol (Daicel Chemical Industries, Plaxel P-2203), which is a reaction product of polypropylene glycol and ε-caprolactone.
, molecular weight approximately 2000.08 valence 57,9) 432 parts,
4.4-Diphenylmethane diisocyanate) 84.9 parts were charged, and after raising the temperature, the reaction was carried out at 75°C for 10 hours.Then, the reaction solution was cooled to 60°C, and 26.2 parts of 2-hydroxyethyl acrylate and 0 parts of methoquinone were charged. .27 parts and 0.11 parts of di-n-butyltin dilaurate were added, and after heating, 75
The reaction was carried out at ~80°C. The product has the following properties.

Viscosity (80°G) 88P refractive index (20°
G) 1.4920 [Production example of monoacrylate of 2 moles of ε-caprolactone adduct of nonylphenol with 4 moles of ethylene oxide] Production example 7, 21 reactions equipped with a stirrer, temperature control device, thermometer, and condenser In a vessel, 624 parts of a compound having the following structure, 108 parts of acrylic acid, 16.8 parts of radruenesulfonic acid, 1.0 part of hydroquinone, 560 parts of benzene, and 140 parts of cyclohexane were charged and heated, and the resulting water was Distilled and condensed together with the solvent, removing only water from the system in a separator, and returning the solvent to the reactor. When 18 parts of water was produced, it was cooled. The reaction temperature was 80~
It was 87°C. The reaction mixture was dissolved in 1040 parts of benzene and 260 parts of cyclohexane, neutralized with 20% aqueous sodium hydroxide solution, and then washed and steamed three times with 500 parts of 205 brine. The solvent was distilled off under reduced pressure to obtain 596 parts of a pale yellow liquid.

This material has the following properties.

Specific gravity (25°C) 1.045 Viscosity (25°G) 68.8 CPS saponification value 248 ■KOB/g acid value
0.04 qKOH/g [Example of ultraviolet curable resin composition] Example 1゜Carbonate diol diacrylate 1 obtained in Production Example 1
0 parts, 40 parts of polyurethane acrylate obtained in Production Example 4, 40 parts of monoacrylate of 2 moles of ε-caprolactone added to nonylphenol with 4 moles of ethylene oxide, 1 part of tetrahydrofurfuryl alcohol
Monoacrylate I/-t (Nippon Kayaku tmH, KAYARAD T
Resin composition A was prepared by mixing 10 parts of C-1108), 5 parts of 1-hydroxychlorohexyl phenyl ketone (Ciba Geigy, Irgacure 184), and 0.01 part of methylhydroquinone. Table 1 shows the properties of the resin composition and its cured product.

Example 2゜Carbonate diol diacrylate 4 obtained in Production Example 2
0 parts, 25 parts of polyurethane acrylate obtained in Production Example 4, 25 parts of monoacrylate of 2 moles of ε-caprolactone adduct of 4 moles of ethylene oxide of nonylphenol, and 1-hydroxychlorohexyl phenyl ketone (Ciba Geigy , Irgacure 184) 5
1 part and 0.01 part of methylhydroquinone were mixed to prepare a resin composition B. Table 1 shows the properties of the resin composition and its cured product.

Example 3゜Carbonate diol diacrylate 2 obtained in Production Example 2
0 parts, 20 parts of the polyurethane acrylate obtained in Production Example 5, 40 parts of monoacrylate of 2 moles of ε-caprolactone adduct of nonylphenol with 4 moles of ethylene oxide, 20 parts of monoacrylate of 7 moles of ethylene oxide adduct of nonylphenol, and A resin composition C was prepared by mixing 5 parts of 4'-dodecyl-2-hydroxy-2-methylpropiophenone (Merck, Crocure 953) and 0.01 part of methylhydroquinone.

The properties of the resin composition and its cured product are shown in Table 1.

Example 4゜10 parts of carbonate diol dimethacrylate obtained in Production Example 3, 10 parts of carbonate diol diacrylate obtained in Production Example 2, 30 parts of polyurethane acrylate obtained in Production Example 6, 10 parts of phenoxyethyl acrylate, nonylphenyl 40 parts of monoacrylate of 7 mole adduct of ethylene oxide and 184.5 parts of Irgacure,
A resin composition was prepared by mixing 0.01 part of methylhydroquinone. First, the characteristics of the resin composition and its cured product are
Shown in the table.

Comparative Example For comparison, 1) esoto 950

Table 1 shows the properties of the resin composition and its cured product.

Table 1 In Table 1 above, measurement of [Shore hardness A]: Compositions A, B, C, D, and E were measured under a light source with a high-pressure mercury lamp (!iV at lamp exit 2) arranged in parallel. Irradiation was performed at a position of 8 cm (conveyor speed: 30 m/m1n) to produce a sheet with a thickness of 250 μm, and this was used for measurement. The measurement method is JIS-Z224
This was carried out according to method 6.

Measurement of [Glass Transition Point]: A test piece was prepared under the same conditions as those used for the measurement of Shore hardness A above. Using this, a viscoelastic spectrometer (Iwamoto Urasakusho ■Rise)
Measured using

Measurement of [Young's modulus, kg/Cm2]: A test piece was prepared under the same conditions as those used for the measurement of Shore hardness A above. Using this to change the temperature, Young's modulus (kg
/cm) was measured.

Measurement of [Water Absorption]: A test piece was prepared under the same conditions as those used for the Shore hardness measurement described above. Using this, it was immersed in pure water at 20°C for 24 hours, the weight before and after the test was measured, and the increase in weight due to water absorption was expressed in %.

Example 5: A base material for optical glass fiber was heated to about 2000°C, and 5
It was spun into an optical glass fiber with an outer diameter of 125 microns at a speed of m/sec. In the next successive step, each of the resin compositions A to D shown in Examples was applied to the optical glass fiber by a die coating method, and then cured by irradiation with ultraviolet rays using a 2KW high-pressure mercury lamp. In the obtained coated optical glass fiber, no change in transmission loss was observed up to -60°C when any of resin compositions A to D was applied.

(Effects of the Invention) The novel resin composition and coating agent of the present invention have a fast curing speed, a flexible resin film, a low glass transition point, a low water absorption rate, and a wide temperature range from high to low temperatures. There is little change in film properties over time, making it suitable for coating optical glass fibers for light transmission.

Claims (2)

[Claims] (1) Carbonate diol (average molecular weight 500-30
00) di(meth)acrylate (A), polyurethane (meth)acrylate (B), a monoethylenically unsaturated monomer (C), and a photopolymerization initiator (D) as an optional component. thing. (2) Carbonate diol (average molecular weight 500-30
00) di(meth)acrylate (A), polyurethane (meth)acrylate (B), monoethylenically unsaturated monomer (C) and photopolymerization initiator (D). agent.