JP2002322228A - Electron ray-curing liquid resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a new electron ray-curing liquid resin composition having excellent curing property by the irradiation of electron rays and excellent in cured membrane characteristic. SOLUTION: The electron ray-curing liquid resin composition comprises (A) 100 pts.wt. of a polyether polyurethane having at least two vinyl ether groups in a molecule and a number average molecular weight of 800-10,000 and (B) 10-100 pts.wt. of a compound having at least one (meth)acrylic group in a molecule. Based on 1 mole of the vinyl ether group in the whole composition, the content of the (meth)acryl group is >=1 mole in the whole composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid electron beam-curable resin composition having excellent high-speed coating properties, and more particularly to a primary coating material, a secondary coating material, and an optical fiber core of an optical fiber used as a coating material for an optical fiber. The present invention relates to a liquid electron beam-curable resin composition suitable as a coating material such as a fiber tape material.

[0002]

2. Description of the Related Art As optical communication fibers, there are various types such as silica glass, multi-component glass, plastics, etc. Due to its high durability and transmission capacity, quartz glass-based materials are widely used in a wide range of fields. However, since the silica glass-based fiber is extremely thin and changes may occur due to external factors, the silica glass-based optical communication fiber is a soft liquid curable material that is previously cured on a fused-spun silica glass fiber. After coating and curing with a resin and performing a primary coating, a secondary coating is further applied with a hard liquid curable resin of a cured product in order to protect the primary coating layer. This is called an optical fiber core wire. Further, several (usually four or eight) core wires are bundled, and a tape material is applied and hardened.
Tape cores are manufactured.

As these coating materials, urethane acrylate-based ultraviolet curable resin compositions have been proposed, and are disclosed in Japanese Patent Publication No. 1-16944 and Japanese Patent No. 2522.
As described in U.S. Pat. No. 663 and Japanese Patent No. 2547021, an ultraviolet liquid curable composition comprising a urethane acrylate oligomer, a reactive diluent and a photopolymerization initiator is known. However, in recent years, the drawing speed of the optical fiber has been increased in order to improve productivity, and a resin having good curability with a small amount of irradiation of ultraviolet rays is required. From the viewpoint of increasing the curing speed, JP-A-10-204250 discloses that
A resin composition containing a compound containing a (meth) acryloyl group and a compound containing an N-vinyl group is described. However, when a compound containing an N-vinyl group is contained, the water absorption increases, and after the fiber is laid. Had a problem of poor reliability over time. As another solution, there is a method of increasing the number of ultraviolet lamps to be irradiated at the time of drawing an optical fiber to increase the amount of ultraviolet irradiation, but there is a problem that curing in a limited space is limited.

The present invention has been made in view of the above circumstances, and has excellent curability and excellent properties of a cured film to be obtained.
In particular, it is an object of the present invention to provide a novel liquid electron beam curable resin composition having a small water absorption of a cured film.

[0005]

Means for Solving the Problems and Embodiments of the Invention The present inventors have made intensive studies to achieve the above object, and as a result, have found that a liquid electron beam-curable resin composition has a (meth) acrylic group. By adding a compound containing a vinyl ether group (hereinafter, referred to as a vinyl ether compound) in addition to the polyether polyurethane containing and / or the reactive diluent, the curability with a small electron beam irradiation amount is good. It was also found that a cured film having a low water absorption was obtained. Generally, it is known that a vinyl ether compound generates an acid upon irradiation with an onium salt or the like and undergoes cationic photopolymerization, and is often used by being mixed with a plurality of vinyl ether compounds or epoxy compounds.
However, there are few reports on its use as a radical polymerization with (meth) acrylic compounds, and it is well known in particular about the behavior during irradiation with ionizing radiation such as an electron beam without using a radical polymerization initiator or a photocationic polymerization initiator. Not.
The present inventors have found that a mixed system of a vinyl ether compound and a (meth) acrylic compound can be cured by irradiation with an electron beam without the presence of a radical polymerization initiator or a cationic photopolymerization initiator, and constitute the present invention. Reached.

Accordingly, the present invention relates to (A) a compound having a number average molecular weight of at least 2 having at least two vinyl ether groups in one molecule.
00 to 10,000 polyether polyurethane 100
Parts by weight, (B) 10 to 100 parts by weight of a compound having at least one (meth) acryl group in one molecule,
Provided is a liquid electron beam-curable resin composition, characterized in that the (meth) acrylic group in the entire composition is at least 1 mol per 1 mol of the vinyl ether group in the entire composition.

Further, according to the present invention, a polyether polyurethane having at least two vinyl ether groups in one molecule is obtained by reacting a polyether polyol, a polyisocyanate compound and a hydroxyl group-containing vinyl ether compound. The present invention provides the above liquid electron beam-curable resin composition, wherein the hydroxyl group-containing vinyl ether compound is hydroxyethyl vinyl ether.

Hereinafter, the present invention will be described in more detail.
The liquid electron beam-curable resin composition of the present invention comprises (A) a polyether polyurethane having a number average molecular weight of 800 to 10,000 having at least two vinyl ether groups in one molecule, and (B) at least one polyether polyurethane in one molecule. The composition contains a compound having one (meth) acrylic group, and the amount of the (meth) acrylic group in the whole composition is 1 mol or more per 1 mol of the vinyl ether group in the whole composition.

The polyether polyurethane having at least two vinyl ether groups in one molecule, which is the component (A) of the present invention, has a number average molecular weight of 800 to 10,000. When the number average molecular weight is less than 800, the obtained cured film has a small elongation and is easily peeled off at the time of coating. When it is more than 10,000, the cured film has low hardness and Young's modulus, is easily damaged, and is easily damaged. Function will not be fulfilled.

The polyether polyurethane having at least two vinyl ether groups in one molecule of the present invention can be obtained, for example, by reacting a diol having an oxyalkylene group having 2 to 10 carbon atoms with a diisocyanate and a vinyl ether compound having a hydroxyl group. can get.

Here, specific examples of the diol having an oxyalkylene group having 2 to 10 carbon atoms include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, 2-methyltetrahydrofuran glycol, 3-methyltetrahydrofuran glycol, and polyheptamethylene. Glycol, polyhexamethylene glycol, polydecamethylene glycol, polyalkylene oxide adduct of bisphenol A diol, and the like. Polypropylene glycol, polytetramethylene glycol, 2-methyltetrahydrofuran glycol, 3-methyltetrahydrofuran glycol, Methyltetrahydrofuran glycol is preferred. As the polyalkylene oxide, not only the homopolymer but also a random or block copolymer thereof can be used.

[0012]

Examples of the diisocyanate include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylene diisocyanate, 1,4-xylene diisocyanate, 1,5-naphthalene diisocyanate, m-phenylene diisocyanate and p-isocyanate. Phenylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-
Examples include trimethylhexamethylene diisocyanate, and among them, 2,4-tolylene diisocyanate, isophorone diisocyanate and the like are preferable. These diisocyanates may be used alone or in combination of two or more.

Further, examples of the compound having a vinyl ether group include a vinyl ether compound having a hydroxyl group. Vinyl ether compounds having a hydroxyl group, for example, hydroxyethyl vinyl ether,
Examples thereof include hydroxyalkyl vinyl ether compounds such as hydroxypropyl vinyl ether and hydroxybutyl vinyl ether, cyclohexane dimethanol monovinyl ether, hexanediol monovinyl ether, and diethylene glycol monovinyl ether. Among them, hydroxyethyl vinyl ether is preferable because of its excellent electron beam curability.

The polyether polyurethane having two vinyl ether groups in one molecule can be prepared, for example, by the above-mentioned diol and diisocyanate by OH / NCO = 0.5 by a conventional method.
After reacting at 2.0 to 2.0 (molar ratio), it can be further produced by reacting a compound having a vinyl ether group.

Here, in the present invention, a polyether polyurethane oligomer having at least two vinyl ether groups in one molecule has a vinyl ether group CH ₂ =
Structure between -OCONH- urethane group is an ethylene group _-CH 2 CH ₂ from CHO- - is preferably a polyether polyurethane is preferably used having a vinyl ether group at the terminal.

The compound ((meth) acryl compound) having a (meth) acryl group, which is the component (B) of the present invention, comprises:
The component (A) has an effect of lowering the viscosity of a polyether polyurethane having at least two vinyl ether groups in one molecule, and has an effect of further increasing the curing speed.

Specific examples of the (meth) acrylic compound include, for example, isobornyl (meth) acrylate, bornyl (meth) acrylate, tricyclodecanyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentane Alicyclic structure-containing (meth) acrylates such as pentenyl (meth) acrylate, cyclohexyl (meth) acrylate, and 4-butylcyclohexyl (meth) acrylate; glycidyl (meth) acrylate;
(Meth) acrylates having an epoxy group or a hydroxyl group, such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 2-hydroxybutyl (meth) acrylate; methyl (meth) acrylate, ethyl (meth) acrylate , Propyl (meth) acrylate, isopropyl (meth) acrylate, n-
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, undecyl (meth) acrylate, dodecyl (meth) acrylate, Alkyl (meth) acrylates such as lauryl (meth) acrylate, stearyl (meth) acrylate, and isostearyl (meth) acrylate; tetrahydrofurfuryl (meth) acryle G, 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, methoxypolyethylene glycol (meth) acrylate, methoxypolypropylene glycol (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, 7-amino-3,7-dimethyl Octyl (meth) acrylate, a compound represented by the following formula (1) or (2) can be mentioned.

[0019]

Embedded image (Wherein, R ¹ represents a hydrogen atom or a methyl group, R ² represents an alkylene group having 2 to 6, preferably 2 to 4 carbon atoms,
R ³ is a hydrogen atom or 1 to 12 carbon atoms, preferably 1 to 9
And p represents 0 to 1
2, preferably an integer of 1 to 8. )

[0020]

Embedded image (Wherein, R ⁴ represents a hydrogen atom or a methyl group, R ⁵ represents an alkylene group having 2 to 8, preferably 2 to ⁵ carbon atoms,
THF represents a tetrahydrofuryl group, and q represents a number of 1 to 8, preferably 1 to 4. )

Such (meth) acrylate compounds include, for example, Aronix M-111, M-113, M-11
4, M-117 (all manufactured by Toagosei); KAYARAD
It can be obtained as a commercial product such as TC110S, R629 and R644 (all manufactured by Nippon Kayaku); Further, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, ethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, 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, tricyclodecane dimethanol di (meth) acrylate, ethylene oxide of bisphenol A or di (meth) acrylate of a diol adduct of propylene oxide, ethylene oxide of hydrogenated bisphenol A Alternatively, di (meth) acrylate of a diol, which is an adduct of propylene oxide, epoxy (meth) acrylate obtained by adding (meth) acrylate to diglycidyl ether of bisphenol A, triethylene glycol divinyl ether, and the like can be given. Commercial products include, for example, Iupima UV SA1002, SA200
7 (manufactured by Mitsubishi Chemical); Viscoat 700 (manufactured by Osaka Organic Chemical); KAYARAD R-604, R-684;
DPCA-20, DPCA-30, DPCA-60, D
PCA-120, HX-620, D-310, D-33
0 (all manufactured by Nippon Kayaku); Aronix M-210, M
-215, M-220, M-315, M-325 (all manufactured by Toagosei); Newpole BPE, BP, HA6
0S (all manufactured by Sanyo Chemical Industries, Ltd.) and the like. These (meth) acrylic compounds may be used alone or in combination of two or more.

The (meth) acrylic compound is used in an amount of 10 to 100 parts by weight, preferably 10 to 80 parts by weight, per 100 parts by weight of the polyether polyurethane having two vinyl ether groups in one molecule. You. If the amount of the vinyl ether compound is less than 10 parts by weight, the effect of accelerating the decrease in viscosity or irradiation with electron beams is small. If the amount is more than 100 parts by weight, the obtained cured film is hard and has low elongation. May not be obtained.

In addition to the above blending weight, the number of (meth) acryl groups in the total composition is at least 1 mol, preferably at least 2 mol, more preferably from 2 to 1 mol of vinyl ether groups in the entire composition. Desirably, it is 4 moles. If the number of (meth) acryl groups in the entire composition is less than 1 mol based on 1 mol of the vinyl ether groups in the entire composition, the curability after electron beam irradiation may be insufficient.

In the present invention, the number average molecular weight having at least two vinyl ether groups in one molecule is from 800 to 10,
000 polyether polyurethane and a compound having at least one (meth) acryl group in one molecule, and a compound having a number average molecular weight of 800 to 10,000 having at least two (meth) acryl groups in one molecule. Polyether polyurethane may be added.

The liquid electron beam-curable resin composition of the present invention may further contain, if necessary, a sensitizer, an antioxidant, an ultraviolet absorber, an organic solvent, a plasticizer, a surfactant, a silane coupling agent, Additives such as color pigments and organic or inorganic particles can be added within a range that does not impair the purpose of the present invention.

When the liquid electron beam-curable resin composition of the present invention is used for a coating material for an optical fiber, it can be prepared by mixing the above-mentioned necessary components and then stirring and mixing. From the point of compatibility with the normal manufacturing conditions of the optical fiber cable,
s (25 ° C.), particularly 1,000-
A range of 6,000 mPa · s (25 ° C.) is desirable.

The optical fiber coating material includes a primary material having a small Young's modulus and a secondary material having a high Young's modulus. It is preferable that these mechanical properties have a small change with temperature. To reduce the change in mechanical properties due to temperature,
In addition to the polyether polyurethane oligomer having a number average molecular weight of 800 to 10,000 and the reactive monomer described above, a polyurethane having a number average molecular weight of less than 800 may be added. This polyurethane may contain either a vinyl ether group or a (meth) acryl group at the terminal.

The method and conditions for curing by irradiating with an electron beam include a voltage of 30 to 200 kV, preferably 50 to 17 kV.
The electron is accelerated at 0 kV, and the absorbed dose is 10 to 100 kGy,
Preferably 20 to 100 kGy, more preferably 30 to 100 kGy
Irradiation at 100 kGy is desirable.

[0029]

EXAMPLES The present invention will be described below in detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples. In addition, in the following examples, a part shows a weight part. Example 1 A reaction vessel was charged with 118.89 gr of polypropylene glycol having a number average molecular weight of 1018, 0.2 gr of dibutyltin dilaurate, and 0.1 gr of 2,6-di-tert-butylhydroxytoluene, and was cooled to 15 ° C. or less under dry nitrogen. 40.68 gr of 2,4-tolylene diisocyanate was added dropwise at such a speed as to keep the temperature at. Then, the temperature was raised to 30 ° C., and the mixture was reacted for 2 hours. Then, 20.58 gr of hydroxyethyl vinyl ether was added, and the mixture was reacted at 50 to 60 ° C. for 3 hours to obtain a vinyl ether group-terminated polyether urethane oligomer (referred to as oligomer A). Was. Oligomer A and isobornyl acrylate are mixed, and the ratio of the number of moles of acryl group to 1 mole of vinyl ether group is 1,
Samples Nos. 3 and 5 were prepared, and the samples were referred to as Samples -2 to 4, respectively.

Comparative Example 1 For comparison, a sample was prepared using the oligomer A and isobornyl acrylate in Example 1 so that the number of moles of acryl group was 0.5 per mole of vinyl ether group. Sample 1 was used.

The above Samples 1 to 4 were applied on a glass plate to a thickness of about 60 μm using an applicator, and a voltage of 10 μm was applied.
An electron beam obtained by accelerating electrons at 0 kV was irradiated at absorption doses of 20, 30, and 100 kGy, and the curability was examined by gel fraction, Young's modulus at 100 kGy, and elongation at break. Table 1 shows the results.

(Measurement method of gel fraction of cured film) After the cured film was immersed in acetone for 16 hours, the film was taken out and dried at 70 ° C for 4 hours, and the weight change ratio was determined by the following equation. Gel fraction = (film weight after drying / initial film weight) × 100 (%) (Method of measuring Young's modulus of cured film) 25 ° C., relative humidity 50
% After conditioning the cured film for 24 hours.
2.5% under the conditions of 5mm and pulling speed of 1mm / min
The tensile modulus was measured. (Measurement method of elongation at break) After conditioning the cured film for 24 hours at 25 ° C. and 50% relative humidity, 25 m between the marked lines
m and the tensile speed were 50 mm / min. (Method of measuring water absorption of cured film) A cured film having a length of 5 cm and a width of 5 cm is dried at 50 ° C for 24 hours to volatilize uncured components, and then immersed in pure water at 25 ° C for 24 hours.
The weight was measured (measured value is (A)), the film was taken out, dried at 50 ° C. for 24 hours, and the weight was measured (measured value was (B)). Water absorption = ((A)-(B)) / (B) × 100 (%)

[0033]

[Table 1]

From Table 1, it can be seen that the curability is improved as the ratio of the acryl group to the vinyl ether group is increased.
As described above, the gel fraction was 90% or more when the absorbed dose was 30 kGy or more.

Example 2 A reaction vessel was charged with 118.89 gr of polypropylene glycol having a number average molecular weight of 1018, 0.4 gr of dibutyltin dilaurate, and 0.1 gr of 2,6-di-tert-butylhydroxytoluene.
Under dry nitrogen, 93.52 gr of 2,4-tolylene diisocyanate was added dropwise at a rate kept at 15 ° C. or lower. Then, the temperature was raised to 30 ° C., and after reacting for 2 hours, 70.73 gr of hydroxyethyl vinyl ether was added, and 50-60
The mixture was reacted at a temperature of 3 ° C. for 3 hours to obtain a polyether urethane oligomer having a vinyl ether group terminal (hereinafter referred to as “oligomer B”). In addition, 118.89 gr of polypropylene glycol having a number average molecular weight of 1018, 0.4 gr of dibutyltin dilaurate, and 0.1 gr of 2,6-di-tert-butylhydroxytoluene are charged into a reaction vessel, and the rate at which the temperature is kept at 15 ° C. or lower under dry nitrogen. Then, 93.52 gr of 2,4-tolylene diisocyanate was added dropwise. Next, the temperature was raised to 30 ° C., and after reacting for 2 hours, 93.21 gr of hydroxyethyl acrylate was added and reacted at 50 to 60 ° C. for 3 hours to obtain a vinyl ether group-terminated polyether urethane oligomer (referred to as oligomer C). Was. The oligomer B, the oligomer C, and the isobornyl acrylate were mixed to prepare a sample in which 1,2,5 mol of an acryl group per 1 mol of a vinyl ether group in the entire system was prepared. And

The above Samples-5 to 7 were coated on a glass plate to a thickness of about 60 μm using an applicator, and a voltage of 10 μm was applied.
An electron beam obtained by accelerating electrons at 0 kV was irradiated at absorption doses of 20, 30, and 100 kGy, and the gel fraction, Young's modulus at 100 kGy, elongation at break, and water absorption were examined. The results are shown in Table 2. As a result, the characteristics of the optical fiber as the secondary coating material were sufficiently satisfied.

[0037]

[Table 2]

[0038]

According to the present invention, it is possible to obtain a novel liquid electron beam-curable resin composition having good curability by irradiation with an electron beam and excellent cured film properties.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G02B 6/44 301 G02B 6/44 301A F-term (Reference) 2H050 BA17 BB14 BB34 4J011 QA03 QA23 QA24 QA33 QA34 QA45 QB16 QB24 UA03 WA03 4J027 AG12 AG13 AG22 BA07 BA08 BA10 BA11 BA19 BA24 BA26 CC06 4J038 FA122 FA132 FA152 FA162 FA172 FA281 NA04 NA11 NA23 PA17 PB08 PC03

Claims (3)

[Claims] (A) a number average molecular weight having at least two vinyl ether groups in one molecule of from 800 to 10,000.
0 of 100 parts by weight of a polyether polyurethane, (B) 10 to 100 parts by weight of a compound having at least one (meth) acryl group in one molecule, and based on 1 mol of vinyl ether groups in the whole composition. A liquid electron beam-curable resin composition, wherein the (meth) acrylic group in the whole composition is 1 mol or more. 2. A polyether polyurethane having at least two vinyl ether groups in one molecule, obtained by reacting a polyether polyol, a polyisocyanate compound and a hydroxyl group-containing vinyl ether compound, wherein said hydroxyl group-containing vinyl ether compound The liquid electron beam-curable resin composition according to claim 1, wherein is a hydroxyethyl vinyl ether. 3. The liquid electron beam-curable resin composition according to claim 1, which is a coating material for an optical fiber.