JPH01170A - Coating material composition for optical communication glass fiber - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a coating composition for optical communication fibers.

(Prior art) Optical communication glass fibers have extremely small diameters and are therefore weak in strength, so in order to avoid surface contamination, they are coated with plastic such as nylon, polyethylene, polyurethane, epoxy resin, silicone resin, etc.
・(-Next coating) is carried out within the -film.

In addition, this primary coat material is
As shown on page 12 of Publication No. 34, it is preferable to have a higher refractive index than the cladding layer of the glass fiber for optical communication.

Furthermore, as shown in Japanese Patent Application Laid-Open No. 52-150050, silicone resin having a higher refractive index than the cladding layer is said to be the most preferable material for improving the characteristics of optical communication fibers.

Regarding silicone as a primary coating material for optical communication fibers, an alkenyl group-containing organopolysiloxane and an organohydrodiene polysiloxane containing 3i-1-14% are reacted in the presence of a platinum-based catalyst. So-called addition reaction type products are preferred because they cure quickly with moderate heating, but economically advantageous ordinary methylhydrodiene polysiloxanes contain alkenyl groups containing phenyl groups. Since it lacks compatibility with polysiloquiline, low-molecular or cyclic siloxanes that have good compatibility with this type of alkenyl group-containing polysiloxane have been used as organohydrodiene polysiloxanes.

However, since the organohydrodiene polysiloxane used here is highly volatile, air bubbles tend to form in the cured film and there is a risk of ignition. Afterwards, attempts were made to use methylphenylhydrodiene polysiloxane with low volatility (Japanese Patent Application Laid-Open No. 57-17
(Refer to Publication No. 448), as shown in Proceedings of the 1981 National Conference of the Institute of Electronics and Communication Engineers, NQ1126, hydrogen generated during curing of an addition reaction curable silicone composition can be used to control the bonding rate. There is a problem in that it reacts with trace amounts of glumanium as an agent to form hydroxyl groups, which absorb infrared light and deteriorate optical transmission characteristics.Therefore, there was a need to develop a method to suppress the generation of hydrogen gas. .

Furthermore, as shown in JP-A-61-52616, a method has been proposed in which the amount of platinum catalyst contained is increased to reduce the amount of hydrogen gas generated.

(Problems to be Solved by the Invention) However, the above-mentioned conventional techniques were not yet perfect and had many drawbacks.

That is, if the amount of platinum catalyst is simply increased, the coloring of the cured product will be significant, and the appearance will be poor.
Since there were many catalysts, it was difficult to control the reaction rate and change over time. Furthermore, this primary coating material has the disadvantage that it is difficult for air bubbles to escape.

The present inventors have made extensive studies to solve the above-mentioned drawbacks and have arrived at the present invention. In other words, the present invention has the characteristics that air bubbles are easily released during use, almost no hydrogen gas is generated during curing, and the curing process is quick. The object of the present invention is to provide a coating material composition for optical communication glass fibers, which has the characteristic of forming a smooth coating with a solder coating, and can be suitably used as a coating material for optical communication glass fibers, particularly as a primary coating material.

(Structure and operation of the invention) The above-described present invention has the following features: (A) having at least one vinyl group at both ends of the molecular chain, and having a molar ratio of methyl groups and phenyl groups contained in the molecule (1:1 to 1); 30:1) and within the range of 2
Methylphenylpolysiloxane having a viscosity at 5°C within the range of 100 to 15,000 centipoise, hydrogen group), R25iO unit (R2 is a monovalent hydrocarbon group or hydrogen atom), R3SiO3/2 unit (R3 is 1 valent hydrocarbon group or hydrogen atom) and/or Si 02 units, and the molar ratio of the monovalent hydrocarbon group other than the aryl group contained in the molecule to the aryl group is (
1:1 to 100:1), and the average molecular weight is 50
The molar ratio of the silicon-bonded hydrogen atoms in the organohydrodiene polysiloxane main component and the total vinyl groups in component (A) is 0.75:1.00 to 1.05:1. 00, and (C) a coating material composition for an optical communication fiber, which is characterized by comprising a platinum-based compound or the like.

To explain this in detail, component (A) is the main component of the wood-based adhesive composition, and is crosslinked by component (B) due to the catalytic action of component Q to form a flexible silicone rubber. This component is a methylphenylpolysiloxane having at least one vinyl group at both ends of its molecular chain.

The molecular structure is usually linear, but may be slightly branched. Such polysiloxanes include, for example, a homopolymer consisting only of methylphenylsiloxane units, a copolymer consisting of dimethylsiloxane units and methylphenylsiloxane units, and a copolymer consisting of dimethylsiloxane units and diphenylsiloxane units. At least one vinyl group exists at both ends of the molecular chain of such methylphenylpolysiloxane,
Although it is necessary to do so, in addition to the vinyl group, only a methyl group, only a phenyl group, or both a methyl group and a phenyl group may be present. In addition to the vinyl groups at both ends of the molecular chain, a small number of vinyl groups may be included as methylvinylsiloxane units forming the main chain.

The molar ratio of silicon-bonded methyl groups to silicon-bonded phenyl groups in such methylphenylpolysiloxane needs to be within the range of 1:1 to 30:1,
It is preferably within the range of 1:1 to 7:1. This is because when the molar ratio of methyl groups to phenyl groups falls outside these ranges, the refractive index of the cured film of the composition of the present invention will be lower than the refractive index of the cladding layer of the glass fiber for optical communication (usually 1.45 to 1. 46) and is no longer essential as a primary coating material. The viscosity of this methylphenylpolysiloxane needs to be within the range of 100 to 15,000 centipoise at 25°C, and 500 to 10 centipoise.
000 centipoise is preferred. This is 100
This is because if centivoice does not form, the cured film will become too hard and the viscosity of the composition itself will become too low, making it impossible to coat it on glass fibers for optical communications. on the other hand,
If it exceeds 15,000 centivoice, the cured film will become too flexible, and the viscosity of the composition itself will become too high, resulting in poor coating workability.

Component (2) is a component that characterizes the present invention.

This acts as a crosslinking agent for component (A), and due to the catalytic action of component 0, silicon-bonded hydrogen atoms in this component are
) It cures by an addition reaction with the lower alkenyl group in the component, and exhibits the effect of forming a cured film, that is, a silicone rubber layer, on a glass fiber for optical communication, which generates almost no hydrogen gas.

Such component (2) is H81Ot/2 units, R15i
It is essential that it is an organohydrodiene polysiloxane consisting of O units, R3Si 03/2 and/or Si 02 units.

Here, R1 is an alkyl group such as a methyl group, an ethyl group, or a propyl group; an aryl group such as a phenyl group or a tolyl group; a cycloalkyl group such as a dichlorohexyl group; or a hydrogen atom thereof is partially substituted with a halogen atom, etc. It is a monovalent hydrocarbon group represented by a group, and R2 and R3 are
It is a monovalent hydrocarbon group or a hydrogen atom similar to R1.

It should be noted that the molar ratio of the monovalent hydrocarbon group other than the aryl group in component (B) to the aryl group is within the range of 1:1 to 100:1 from the viewpoint of increasing the curing wave II refractive index. is necessary. Further, in the above formula, representative examples of the group containing a silicon atom ≠ bonded hydrogen atom existing at the molecular chain end of the nohydrodiene polysiloxane include a dimethylhydrodiene siloxy group and a methylphenylhydrodiene siloxy group. Furthermore, a silicon-bonded hydrogen atom may be contained in the R3SiO unit, that is, the unit that forms the main chain, and/or the R3Si03/2 unit, that is, the unit that forms the branched chain. The number of atomically bonded hydrogen atoms is 10 relative to the total amount of silicon-bonded hydrogen atoms contained in the component (8).
It is preferably within the range of 50% to 50%.

Further, this component may contain a small amount of hydroxyl group or alkoxy group bonded to a silicon atom.

Specific examples of such component (2) include dimethylbolysiloxane endblocked with dimethylhydrogensiloxy groups at both ends, dimethylsiloxane/methylphenylsiloxane copolymer endblocked with dimethylhydrogensiloxy groups at both ends,
Both.

Dimethylpolysiloxane endblocked with methylphenylhydrogensiloxy groups, dimethylsiloxane/methylphenylsiloxane copolymers endblocked with methylphenylhydrogensiloxy groups at both ends, organohydrogenpolysiloxanes in which these polysiloxanes are branched, or these polysiloxanes. Examples include resin-like organohydrodiene polysiloxanes having network structure units in addition to siloxane units.

In the present invention, the content of silicon-bonded hydrogen atoms in component (2) is preferably in the range of 0.1 to 0.9% by weight. This is because if the amount is less than 0.1% by weight, curing will be insufficient, whereas if it exceeds 0.9112t%, the coating material may not have a hardness suitable as a coating material for optical communication fibers.

Such organopolysiloxanes include, for example, R3Si
(,!,, A cohydrolyzate obtained by cohydrolyzing R2Si C1!2, R81Ct3 and water, an organohydrodiene polysiloxane and a diorganopolysiloxane, and a heating equilibration reaction in the presence of an acid catalyst. It can be easily obtained by letting

Further, in the present invention, the average valve of component (1) is preferable.

This is because if the average molecular weight of 1 is less than 500, either the boiling point of component (i) is too low or the low-boiling point substances in component (B) increase, which may volatilize during curing.
This is because if it exceeds 000, the number of silicon-bonded hydrogen atoms present at both ends of the molecular chain decreases, resulting in insufficient curing.

The mixing ratio of the components () is such that the molar ratio of all silicon-bonded hydrogen atoms to all lower alkenyl groups in the composition of the present invention is 0.7.
5:1.00 to 1.05:1.00.

(The platinum-based compound of component Q is a catalyst for curing component (A) and component , chloroplatinic acid, alcohol-modified chloroplatinic acid,
Examples include a complex of chloroplatinic acid and olefins, and a complex of chloroplatinic acid or its olefins dissolved in a solvent such as a ketone or ether. Use of component (C) ■ is 0.5 to 1000 p1) as platinum metal based on the total amount of component (A) and component 0.
, preferably within the range of 1 to i o o pp +++.

In the present invention, the curing speed of the composition of the present invention is adjusted,
In order to more effectively suppress the hydrogen gas generation ω, PJ~0
In addition to the other components, it is preferable to add a compound having at least one alkynyl group in one molecule as zero component.

Such component 0 is a compound having at least one alkynyl group in one molecule, and its chemical structure is not particularly limited. Specific examples of this component include the following compounds.

OH0H CH1 CH3Si+OCCmiCH).

CH.

(b) Addition 1 of component 1 means that all alkynyl groups in this component and 0
The ratio of the platinum-based compound in the components is 1.0:1 in terms of heavy ω ratio.
The ratio is required to be 0 to 15.0:1.0, preferably 3.0:1.0 to 12.0:1.0.

In addition, when the composition of the present invention contains component (2), the blending ratio of component (2) described above is the number of moles of all silicon-bonded hydrogen atoms in component (2), and the alkenyl haze and zero in component (A). It is necessary that the ratio of the alkynyl group to the total number of moles of all aliphatic unsaturated groups in the component falls within the range of 0.75:1.00 to 1.05:1.00.

The composition of the present invention comprises the above-described components (A) to 0 or (A
) to 0 components by a conventionally known method.

Further, as a method for coating an optical communication fiber with the composition of the present invention, for example, it can be applied to the surface of the optical communication fiber using a coating die, and then heated and cured to coat the fiber. □Additionally, it is possible to add and blend conventionally known additives, such as silicas such as dry process silica and wet process silica, metal oxides, mica, tarta pigment, etc. to the composition of the present invention as necessary. There is no problem as long as it does not defeat the purpose.

〔Example〕

Next, the present invention will be explained with reference to Examples.

In the examples, parts are 11 parts, percentages are weight D percent,
Vi represents a vinyl group, Me represents a methyl group, and φ represents a phenyl group, and the viscosity is the value at 25°C.

Further, the amount of hydrogen gas generated and the curing rate were measured by the following method.

<Method for measuring the amount of wood gas generated> The composition of the present invention is heated and cured, and a silicone rubber sheet (1
cm+x5c■X0.2CI) and set it to 200
It was heated under the conditions of ℃/1 hour. The generated hydrogen gas was then formulated by gas chromatography. The measured value is converted to the value at 1 atm and 25°C and is μt/? Indicated in units of.

Method for measuring curing speed> The composition of the present invention was measured using a curelastometer (Toyo Baudwin ■).
The silicone rubber was cured under a temperature condition of 150° C., and changes in the hardness of the cured silicone rubber were tracked. The hardness of the completely cured silicone rubber was defined as 100, and the hardening rate was defined as the heating time required to cure the silicone rubber to 70% of this hardness.

[Example 1] 100 parts of methylphenylpolysiloxane with a viscosity of 2000 centipoise and end-blocked with dimethylvinylsiloxy groups at both ends (the molar ratio of methyl groups to phenyl groups is 4=1), (Me)2-based H81O1/2 units, ( Me) 2sio unit, φ2siO unit, φSi 03
2 units, the molar ratio of which is 40:17:17:2
4.5 parts of organohydrodiene polysiloxane (average molecular weight 1500), which is No. 6, and 0.5 parts of an octyl alcohol solution of chloroplatinic acid (0.5% platinum-containing hot water) were mixed to form a coating material composition for optical communication glass fibers. I got something. When the curing speed of this material was measured using a curelastometer, it took 42 seconds to harden to 70%.

When the amount of hydrogen gas generated was measured for a silicone rubber sheet cured by heating at 200° C. for 3 minutes, the amount was 0.5 μi/2. Next, a single optical communication glass fiber with a diameter of 125μ was immersed in the coating composition obtained above in the form of a single wire, which was immediately pulled up and held vertically in hot air at 450°C for 2 seconds.
An optical communication fiber coated with silicone rubber having a film thickness of 40 μm was obtained. This silicone rubber coating layer had no bubbles, was colorless and transparent, and adhered well to the optical communication glass fiber.

[Example 2] 100 parts of methylphenylpolysiloxane with a viscosity of 4000 centipoise and endblocked with dimethylvinylsiloxy groups at both ends (the molar ratio of methyl groups to phenyl groups is 3.5:1), H
(Me) 2si 01 part 2 units and (Me) 28io
The unit, 3.5 parts of φ3i03/2, 0.01 part of 3-methyl-1-butyn-3-ol, and a complex of divinyltetramethyldisiloxane and chloroplatinic acid were mixed to a total concentration of 15 ppm, and optical communication A fiber coating composition was obtained.

The molar ratio of silicon-bonded hydrogen atoms to vinyl groups in this composition was 0.9. When the curing speed of this product was measured using a curelastometer, it took 37 seconds to reach 70% curing.

Further, this material was cured at 200° C. for 3 minutes to prepare a silicone rubber sheet, and then the amount of hydrogen gas was measured in the hydrogen gas generating can, and the amount was 0.2μ6/9.

Next, a single optical communication glass fiber with a diameter of 125μ was immersed in the coating material composition obtained above, and the fiber was immediately pulled up and held vertically in hot air at 450°C for 2 seconds, resulting in a film thickness of 50μ. An optical communication glass fiber coated with silicone rubber was obtained.

This silicone rubber coating layer was colorless and transparent, had no bubbles, and adhered well to the optical communication glass fiber.

[Example 3] 100 parts of methylphenylpolysiloxane with a viscosity of 3000 centipoise and end-blocked with dimethylvinylsiloxy groups (the molar ratio of methyl groups to phenyl groups is 5/1), 1 part of H(Me)2si, 2 units of 30 Mol (Me)2
8 parts of methylphenylhydrodiene polysiloxane with an average molecular weight of 2500, consisting of 50 moles of sio units and 20 moles of φSi○3/2 units, and a complex of chloroplatinic acid and divinyltetramethyldisiloxane were combined at a total concentration of 25 pI)I.
A coating material composition for an optical communication fiber was obtained. Here, the ratio of silicon-bonded hydrogen atoms to vinyl groups in this composition was 0.95. When this composition was kept under 2 mm 1 -1 for 5 minutes, air bubbles mixed in during mixing could be completely removed. Next, the curing speed of this composition was measured using a curelastometer, and it took 44 seconds to reach 70% curing. Moreover, the amount of hydrogen gas generated by this composition is 0.2μ for a silicone rubber sheet cured at 200°C for 1 minute! , /9.

A single optical communication glass fiber with a diameter of 125 μm was immersed in this composition, and immediately pulled up into a vertical shape with a diameter of 45 μm.
When kept in hot air at 0° C. for 2 seconds, an optical communication glass fiber coated with silicone rubber having a film thickness of 40 μm was obtained. This silicone rubber coating layer is colorless and transparent.
There were no bubbles and the optical communication glass fiber was used.

(Example 4) Methylphenylpolysiloxane 100 used in Example 1
In part, H(Me)2si.

1 part 2 units 30 mol, (M(!)ssi O1/21
Part 2Kl, MeφSiO unit 35 mol, Me3i 03
6 parts of methylphenylhydrodiene polysiloxane with an average molecular weight of 2000, consisting of 20 moles of /2 units and 10 moles of SiO2 units, and a complex of chloroplatinic acid and divinyltetramethyldisiloxane were mixed to a total concentration of 2.5 ppn+ and exposed to light. Communication → Diarrhea glass ph? A dressing composition was obtained. The ratio of silicon-bonded hydrogen atoms to vinyl groups in this composition was 0.90. After mixing this composition, it was kept under 2IIIllHg for 5 minutes, and air bubbles mixed in during mixing could be completely removed.

When the curing speed of this product was measured using a key last meter, it took 45 seconds to reach 70% curing. Also, 200℃1
When we measured the amount of hydrogen gas generated using a silicone rubber sheet that was cured in minutes, the amount of hydrogen gas generated was 0.3 μt.
/9.

A glass fiber for optical communication with a diameter of 125μ was immersed in the coating material composition obtained above in the form of a single wire, immediately pulled up, made into a vertical shape, and kept in hot air at 450°C for 2 seconds. A glass fiber for optical communication was coated with approximately 40 μm of silicone rubber. This silicone rubber layer is colorless and transparent, with no bubbles.
It adhered well to glass fiber for optical communications.

[Comparative Example 1] Methylphenylpolysiloxane 100 used in Example 1
Department, H(Me)28i.

1 part 2 units, (Me)ssi 01 /22 parts and SiO2 units, 2 parts of methylhydrodiene polysiloxane containing 0.4% of silicon-bonded hydrogen atoms, and platinum chloride used in Example 1. 0.5 parts of an acidic octyl alcohol solution was thoroughly mixed to obtain a coating material composition for optical communication glass fibers.

The ratio of silicon-bonded hydrogen atoms to vinyl groups in this composition was 0.9. Then, after mixing this composition, 2 m
When the mixture was kept under mHo for 5 minutes, air bubbles mixed in during mixing could not be removed quickly and it took about 20 minutes.

When the curing speed of this product was measured using a curelastometer, it took 70 seconds to reach 70% curing. Also, 2
When we measured the amount of hydrogen gas generated from the silicone rubber sheet using a silicone rubber sheet that had been cured at 0'0℃ for 1 minute, the amount of hydrogen gas generated was 10μI! /9.

A single optical communication glass fiber with a diameter of 125 μm was immersed in this composition, and immediately pulled up and made into a vertical shape.
When kept in hot air at 50° C. for 2 seconds, a glass fiber for optical communication coated with a silicone rubber layer having a thickness of about 40 μm was obtained.

However, the surface of this silicone rubber layer was sticky, making it unsuitable for use as a glass fiber for optical communications.

[Comparative Example 2] Methylphenylborisiloxane 100 used in Example 1
2 parts of methylhydrodienepolysiloxane represented by (in=4-20) and 0.5 part of 0.5% solution of chloroplatinic acid in octyl alcohol were added and mixed well to form an optical communication glass fiber. A dressing composition was obtained. At this time, the molar ratio of all silicon-bonded hydrogen atoms to vinyl groups was 1.2. After mixing this composition, I kept it under 2■1-1 (+) for 5 minutes, but the air bubbles that got mixed in during mixing could not be completely removed. By keeping it for 15 minutes, I was finally able to remove the air bubbles. When the curing speed of the material was measured, it took 20 seconds to reach 70% curing.

Further, when a silicone rubber sheet cured at 200° C. for 1 minute was measured for hydrogen gas generation from the silicone rubber sheet, it was found to be 100 μt/e.

A glass fiber for optical communication with a diameter of 125μ was immersed in the mixed composition in the form of a single wire, immediately pulled up into a vertical shape, and kept in hot air at 450°C for 2 seconds, resulting in a film thickness of about 40.
1q of glass fibers for optical communication having a μ silicone rubber coating layer were produced. Note that the surface of the silicone rubber coating layer was smooth.

[Comparative Example 3] Trisdimethylsiloxyphenylsilane was synthesized. This had a boiling point of 91° C./2.2 mmHq and was easily distilled under reduced pressure. 1.5 parts of this silane was added to 2100 parts of methylphenylpolysiloxa used in Example 1, and an octyl alcohol solution of chloroplatinic acid (platinum metal content 0.5%
) were mixed well to obtain a coating material composition for optical communication glass fibers. When this composition was cured at 200° C. for 3 minutes, the surface of the obtained silicone rubber sheet was not clean and was not suitable as a coating material composition for optical communication glass fibers.

〔Effect of the invention〕

The present invention is a coating material composition for optical communication fibers comprising an addition reaction-curing silicone composition using a specific organohydrodiene polysiloxane as the component (B) as a crosslinking agent, so that it cures quickly and does not mix when mixed. It is characterized by good air bubble removal, and in particular, the amount of hydrogen gas generated is almost zero. Taking advantage of its bending characteristics, it can be suitably used as a coating material for optical communication fibers, especially as a primary coating material.

Furthermore, the optical communication fiber coated with the optical communication fiber composition of the present invention has no transmission loss due to hydrogen gas generated from the coating material, and is suitable as an optical communication fiber for public communication and long-distance communication. Can be used for

Claims (1)

[Scope of Claims] (A) has at least one vinyl group at both ends of the molecular chain, and the molar ratio of methyl groups to phenyl groups contained in the molecule is (
Methylphenylpolysiloxane with a viscosity of 1:1 to 30:1) and a viscosity of 100 to 15,000 centipoise at 25°C. R^1
is a monovalent hydrocarbon group), R^2_2SiO unit (R^2 is a monovalent hydrocarbon group or hydrogen atom), R^3SiO_3/_2 unit (
R^3 consists of a monovalent hydrocarbon group or a hydrogen atom) and/or a SiO_2 unit, and the molar ratio of the monovalent hydrocarbon group other than the aryl group contained in the molecule to the aryl group is (
1:1 to 100:1) and an average molecular weight within the range of 500 to 30,000. Silicon-bonded hydrogen atoms in the main component and all vinyl in component (A). An amount such that the molar ratio of the groups is 0.75:1.00 to 1.05:1.00, and (C) platinum-based compound based on the total amount of components (A) and (B). 1. A coating material composition for optical communication fibers, characterized in that the composition contains a metal in an amount of 0.5 to 1000 ppm.