JPH04271306A - Plastic optical transmission body - 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]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plastic optical transmission body used in optical communications.

0002

2. Description of the Related Art Conventionally, poly(meth)acrylate resins and polycarbonate resins have been used as materials for plastic optical transmission bodies.

In the case of conventional optical transmission bodies using poly(meth)acrylate resin, the heat resistance of the resin is poor;
There is a problem in that characteristics such as transmission loss deteriorate at high temperatures of 0° C. or higher. In order to solve this problem, polycarbonate resins have been used, but at temperatures above 120° C., the properties deteriorate as in the case of using poly(meth)acrylate resins.

0004

SUMMARY OF THE INVENTION An object of the present invention is to solve these problems and provide a plastic optical transmission body with excellent heat resistance.

[0005]

[Means for Solving the Problems] The present invention provides that the cladding and the core have the following formula: (a) General formula:

[In the formula, at least one of R1, R2, R3 and R4 is a group having an unsaturated bond, and the other R1, R2, R3
and R4 is an alkyl group or an aryl group, and X1
, X2, X3 and X4 are hydrogen atoms, alkyl groups or polyorganosiloxane groups, m is a number of 2 or more, n
is a number greater than or equal to 0. ] Ladder type silicone represented by (b) fluoride (meta)
A plastic optical transmission body is provided which is formed from a cured product of a resin composition comprising an acrylate monomer and (c) a polymerization initiator.

[0006] The term "optical transmission body" as used herein includes optical fibers and optical circuits.

In the ladder type silicone represented by formula (I), it is preferred that at least one of R1, R2, R3 and R4 is an alkyl group having a (meth)acrylic group. The lower limit of m is preferably 10, and the upper limit is preferably 1000. The lower limit of n is preferably 10, and the upper limit is preferably 1000. The ladder-type silicone of the cladding and the ladder-type silicone of the core may be the same or different. For ease of manufacture, it is preferable that the ladder-type silicone of the cladding and the ladder-type silicone of the core are the same.

[0008] The ladder type silicone is curable and may be thermosetting or photocurable, preferably thermosetting and photocurable.

The ladder-type silicone used in the present invention has excellent transparency and is suitable for use as a transmission material. Furthermore, it has excellent thermal stability, and exhibits heat resistance that cannot be achieved with general organic resins such as poly(meth)acrylate resins and polycarbonate resins. Therefore, by using ladder-type silicone, it is possible to obtain a plastic optical transmission body with unprecedented heat resistance.

Specific examples of ladder-type silicone include, for example:
It is as follows.

[Chemical formula 3] [In the formula, n is a number from 2 to 1000. ]

embedded image In the formula, m is a number from 2 to 1000, and n is a number from 0 to 1000. ]

The ladder type silicones represented by Chemical Formulas 3 and 4 can be cured by ultraviolet rays, and a core can be formed by irradiation with ultraviolet rays.

[0012] Fluorinated (meth)acrylate is a refractive index controlling monomer. Examples of the fluorinated (meth)acrylate include trifluoroethyl acrylate, trifluoroethyl methacrylate, tetrafluoropropyl acrylate, and tetrafluoropropyl methacrylate. It is desirable that fluorinated (meth)acrylate has significantly inferior photoreactivity compared to ladder-type silicone. In the cladding, the amount of fluorinated (meth)acrylate is 5 to 90 parts by weight based on 100 parts by weight of ladder type silicone.
Parts by weight, preferably 10 to 70 parts by weight. In the core, the amount of fluorinated (meth)acrylate is 5 to 50 parts by weight, preferably 10 to 30 parts by weight, based on 100 parts by weight of ladder type silicone. Since the refractive index of the cladding needs to be lower than the refractive index of the core, the amount of fluorinated (meth)acrylate in the cladding is preferably greater than the amount of fluorinated (meth)acrylate in the core. The fluorinated (meth)acrylate preferably has a boiling point lower than the decomposition temperature of the cured resin composition of the core (for example, 200° C. or lower).

The polymerization initiator is preferably a photopolymerization initiator, especially a compound that easily generates radicals when irradiated with ultraviolet rays. Preferred examples of the polymerization initiator are benzophenone,
Acetophenone, benzyl, benzoin, benzoin methyl ether, benzoin isobutyl ether, benzyl dimethyl ketal, α,α'-azobisisobutyronitrile, benzoyl peroxide, 1-hydroxycyclobexylphenyl ketone, 2,2-dimethoxy-2
-phenylacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one. In particular, 1
-Hydroxycyclohexylphenylketone and 2-hydroxy-2-methyl-1-phenylpropan-1-one are preferred. The amount of polymerization initiator is 1 for ladder type silicone.
20 parts by weight or less, preferably 0.0 parts by weight
It is 1 to 10 parts by weight.

The optical fiber according to the present invention can be manufactured, for example, by the following manufacturing method. First, a core material resin composition is spun from a spinneret at 50° C. to 300° C. to form a core. An optical fiber is produced by die-coating a cladding material resin composition on this core and thermally curing it at 50°C to 300°C.

The optical circuit of the present invention is preferably formed according to the method shown in FIG. First, a low refractive index substrate 11 made of polyfluorinated (meth)acrylate or a cured product of a cladding material resin composition is formed, and a layer 12 made of the resin composition of the present invention is arranged on the substrate 11 (see FIG. A)
). A photomask (not shown) is placed on the resin composition layer 12 and irradiated with ultraviolet rays using an ultraviolet lamp to harden the resin composition in the exposed areas, thereby forming a light guide path pattern to form the core 13. . At this time, the fluorinated (meth)acrylate of the resin composition layer 12 in the exposed part (core part) is at least partially volatilized by the radiant heat of the lamp and the reaction heat during curing (FIG. 1(B)). Next, a plastic optical circuit is obtained by thermally curing the unreacted resin composition in the masked portion to form a cladding 14 (Fig. 1(C)
)). In this method, both the core and the cladding can be formed using the same resin composition, and the casting process of raw materials is done in one step.
Since it only requires one step, it is superior in productivity compared to other plastic optical circuit forming methods.

Further, the optical circuit according to the present invention may be manufactured by a method as shown in FIG. 2, for example. First, a substrate 21 is formed by casting a cladding material resin composition into a mold and curing it (FIG. 2(A)). The substrate 21 may be formed from a material having a low refractive index (for example, polyfluorinated (meth)acrylate) other than the cladding resin composition. Next, a core material resin composition layer 2 is formed on the substrate 21.
2 (Fig. 2(B)). The core 23 of the waveguide pattern is formed by photolithography (FIG. 2(C)
). Further, a cladding material resin composition is cast so as to cover the core 23 and then cured to form a cladding 24, thereby producing an optical circuit (FIG. 2(D)).

[0017]

Preferred Embodiments of the Invention The present invention will be specifically explained below with reference to Examples and Comparative Examples.

Example 1 An optical circuit was manufactured according to the method shown in FIG. On a substrate made of polytrifluoroethyl methacrylate, the formula:

embedded image where n is a number from 400 to 500. ] 40 parts by weight of the curable ladder type silicone, 60 parts by weight of trifluoroethyl methacrylate, 2 which is a photopolymerization initiator.
-Hydroxy-2-methyl-1-phenylpropane-1
A resin composition layer consisting of 1 part by weight of -ON was formed, a photomask was placed thereon, and ultraviolet rays were irradiated to form the core of the light guide pattern. Next, the unreacted resin composition in the masked portion was thermally cured at 200° C. to form a cladding, and a plastic optical circuit was obtained. The physical properties of the obtained plastic optical circuit were as shown in Table 1.

Comparative Example 1 As a core material, 99% by weight of methyl methacrylate and 1% by weight of azoisobutyronitrile as a thermal polymerization initiator were used, and as a cladding material, photopolymerization was initiated with 99% by weight of trifluoroethyl methacrylate. 2-hydroxy-2-methyl-1-phenylpropan-1-one 1
An optical circuit was created using the method shown in FIG. 2 using the added weight percent. The physical properties of the obtained optical circuit were as shown in Table 1.

[0020]

[Table 1]

[0021]

Effects of the Invention The plastic optical transmitter according to the present invention has excellent heat resistance and can withstand high temperatures (120°C or higher, e.g. 130-1
50°C). Therefore, it is effective as an optical transmission body for optical communication systems used under high temperatures.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an optical circuit showing a process outline of a preferred example of manufacturing the optical circuit according to the present invention.

FIG. 2 is a perspective view of an optical circuit showing a process outline of another example of manufacturing the optical circuit according to the present invention.

[Explanation of symbols]

11, 21 Board 12, 22 Resin composition layer 13, 23 core 14, 24 Clad

Claims (4)

[Claims] [Claim 1] The cladding and the core have (a) the general formula: [Formula, at least one of R1, R2, R3 and R4 is a group having an unsaturated bond, and the other R1, R2 , R3
and R4 is an alkyl group or an aryl group, and X1
, X2, X3 and X4 are hydrogen atoms, alkyl groups or polyorganosiloxane groups, m is a number of 2 or more, n
is a number greater than or equal to 0. ] Ladder type silicone represented by (b) fluoride (meta)
A plastic optical transmission body formed from a cured product of a resin composition comprising an acrylate monomer and (c) a polymerization initiator. Claim 2: In ladder type silicone, R1, R
2. The plastic optical transmitter according to claim 1, wherein at least one of R3 and R4 is an alkyl group having a (meth)acrylic group. 3. After disposing a resin composition layer consisting of (a) a curable high refractive index component, (b) a low refractive index component, and (c) a polymerization initiator on a low refractive index substrate, the resin composition A photomask is placed on the material layer and ultraviolet rays are irradiated.The core is cured by curing the resin composition in the exposed area while partially volatilizing the low refractive index component in the exposed area by the radiant heat of the light source and reaction heat. 1. A method for producing a plastic optical circuit, which comprises forming a cladding, and then thermally curing an unreacted resin composition in a masked portion to form a cladding. 4. The method according to claim 3, wherein the curable high refractive index component is the ladder-type silicone (I) defined in claim 1, and the low refractive index component is a fluorinated (meth)acrylate monomer. A method for manufacturing plastic optical circuits.