JPS61275706A - Optical waveguide - Google Patents

Abstract

PURPOSE:To make it possible to freely change the refractive index of an optical waveguide over a wide range by constituting the optical waveguide of a crosslinked siloxane polymer formed by incorporating a substituent for controlling the refractive index into a siloxane polymer by hydrosilylation reaction. CONSTITUTION:The substituent for controlling the refractive index is incorporated into the side chain of the siloxane polymer by the hydrosilylation reaction and the progression of the crosslinking of the siloxane polymer is also made possible, by which the crosslinked siloxane polymer having the different refractive index can be easily obtd. The refractive index of the optical waveguide can be accurately changed over a wide range by such crosslinked siloxane polymer. The optical waveguide having the large opening rate is obtainable by using the crosslinked siloxane polymer incorporated therein with the substituent to decrease the refractive index for the clad and the polymer incorporated therein with the substituent to increase the refractive index for the optical waveguide section, respectively to constitute the optical waveguide.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to an optical waveguide, and more specifically, in an optical waveguide consisting of a cladding and an optical waveguide, at least the optical waveguide portion is hydrosilylated with a substituent for controlling the refractive index. This invention relates to an optical waveguide made of a crosslinked siloxane polymer introduced by reaction.

[Prior Art] Plastic is a relatively inexpensive material for optical waveguides, but there are only four to five types of materials that can be used, and plastic has poor heat resistance.

Siloxane polymers are attracting attention as interesting optical materials because they have excellent transparency and heat resistance, and exhibit rubber-like elasticity after crosslinking and curing.

The use of siloxane polymers as optical waveguides has been known for a long time. For example, Japanese Journal of Applied Physics (JJAP), V
ol, 10. (1971), page 1597, show that silicone rubber can be used as a flexible optical waveguide. 1. Japanese Patent Application Laid-Open No. 150139/1983 discloses a Talara rod for light transmission characterized in that at least one of the core and the cladding is made of silicone rubber.

However, neither of these documents equally mentions a method for manufacturing a high-performance and inexpensive optical waveguide using a transparent siloxane polymer with a controlled refractive index.

On the other hand, siloxane polymers are attracting attention as optical materials intended for applications such as contact lenses.

In the past, for example, U.S. Patent No. 3,228,741 (1
(January 11, 1996) discloses a contact lens made of transparent silicone rubber with good gas permeability.

U.S. Patent No. 3,996,189 (December 7, 1976)
In order to match the refractive index of the silica filler and the refractive index of the siloxane polymer, we used an appropriate amount of a siloxane polymer containing phenyl groups to match the refractive index of the siloxane polymer and the refractive index of the siloxane polymer in the composition. A method is disclosed to match the siloxane polymers and thereby produce optically transparent siloxane polymers. That is, both 6 to 16 mol%
Optically transparent crosslinking is achieved by an addition reaction (hydrosilylation reaction) using a platinum catalyst between a siloxane polymer having vinyl groups at both ends containing a phenyl group and a siloxane polymer having hydrogen-silicon bonds at both ends (5tH). Obtaining siloxane polymer.

Next, the viscosity at 25°C is 100 to 15.000 cP.
A siloxane polymer containing phenyl groups with both ends blocked by vinyl groups (methyl group/phenyl group molar ratio 1/1 to 1)
0/l) and viscosity at 25°C of 0.5 to 5,000c
A coating material for optical communication glass fibers made of a siloxane polymer having a silicon-hydrogen bond (SiH) and a platinum compound [clad material (having a higher refractive index than the core material)] is disclosed in JP-A-55-130844. (1980 I
(Released on October 11th).

On the other hand, U.S. Patent No. 3,341,490 (October 1967)
12), transparent siloxane polymers mixed with reinforcing silica-based fillers are obtained primarily by blending dimethyl/phenylmethylsiloxane copolymers and dimethyl/methylvinylsiloxane copolymers.

All of the above known techniques relate to optically transparent crosslinked siloxane polymers, in which the refractive index is controlled using phenyl group-containing siloxanes.

The specific method is 1.3.5-trimethyl-
1,3,5-triphenylcyclotrisiloxane, 1,
Using a phenyl group-containing cyclic siloxane monomer such as 3,5.7-tetramethyl-1,3,5,futhitraphenylcyclotetrasiloxane, hexaphenylcyclotrisiloxane, octaphenylcyclotetrasiloxane, and crosslinking by addition reaction. vinyl group, silicon-
It is a siloxane polymer obtained by crosslinking polymers such as dimethyl/diphenylsiloxane copolymer, dimethyl/methylphenylsiloxane copolymer, and methylphenylsiloxane polymer into which hydrogen bonds have been introduced, or a blend thereof through an addition reaction.

The above conventional techniques for using siloxane polymers as optical materials have the following drawbacks.

1) Since the refractive index is mainly controlled by phenyl groups, the range of refractive index control is limited.

2) In order to accurately control the refractive index by copolymerizing a phenyl group-containing siloxane monomer, it is necessary to repeat several trial productions from the copolymerization process, which is uneconomical and time-consuming.

3) If you want to obtain several types of crosslinked siloxane polymers with different refractive indexes, it is necessary to perform copolymerization with different amounts of phenyl group-containing siloxane polymer for each type, which causes various problems in terms of quality control, inventory, etc. This will cause some inconvenience.

4) Refractive index control using polymer blends is limited by the compatibility of both polymers, and even if compatible polymers are used, Rayleigh scattering will increase.
Transparency is compromised.

Further, all of the above-mentioned known techniques relate to optically transparent siloxane polymers, and are intended for use in contact lenses, etc., and do not attempt to precisely control the refractive index.

Technology to control the refractive index, which is the basic principle of optical waveguides and optical fibers, is important. The aperture, which is one of the important characteristics of an optical waveguide, is determined by the refractive index of the cladding of the optical waveguide and the optical waveguide. Furthermore, in order to obtain good light transmission characteristics when joining an optical waveguide with other optical elements, optical devices, etc., matching of refractive indexes is necessary. For these reasons, an optical waveguide whose refractive index can be varied accurately and over a wide range is required.

[Object of the Invention] One of the objects of the present invention is to provide an optical waveguide made of a crosslinked siloxane polymer having a substituent that can freely and largely change the refractive index.

Another object of the present invention is that, regardless of the siloxane polymer obtained from the synthesis of phenyl-containing cyclic siloxane polymers,
The object of the present invention is to provide an optical waveguide made of a siloxane polymer in which a substituent for controlling the refractive index is introduced into the side chain of a siloxane polymer by a hydrosilylation reaction and at the same time crosslinked by a hydrosilylation reaction.

Another object of the present invention is to provide an optical waveguide with matched refractive index suitable for joining with other optical elements, optical devices, etc.

[Structure of the Invention] These objects of the present invention are that, in an optical waveguide consisting of a cladding and an optical waveguide (core), at least the optical waveguide is
This is achieved by an optical waveguide characterized by being made of a siloxane polymer into which a substituent for controlling the refractive index is introduced through a hydrosilylation reaction. More specifically, it is an optical waveguide in which at least the optical waveguide portion is made of either the following crosslinked siloxane polymer (A) or (B).

B) Crosslinked siloxane polymer (A) Hydrosilylation reaction between (a) an organic compound having at least one non-conjugated unsaturated bond and a substituent for controlling the refractive index, and (b) a siloxane polymer having silicon hydride The siloxane polymer having the substituent introduced into its side chain is combined with silicon hydride in the siloxane polymer that remains unreacted in the hydrosilylation reaction, and (c) an organic compound having at least two non-conjugated unsaturated bonds. crosslinked siloxane polymer crosslinked by hydrosilylation reaction with a compound (b) crosslinked siloxane polymer (B) (d) siloxane compound or silane compound having at least one silicon hydride and having a substituent for controlling the refractive index and (e) a siloxane polymer having the substituent group introduced into the side chain by a hydrosilylation reaction with a siloxane polymer having a non-conjugated unsaturated bond, and a non-conjugated siloxane polymer in the siloxane polymer that remained unreacted in the hydrosilylation reaction. A crosslinked siloxane polymer crosslinked by a hydrosilylation reaction between an unsaturated bond and (r) a siloxane compound or a silane compound having at least two silicon hydrides.

1. Crosslinked siloxane polymer (A,) As the siloxane polymer (b) having silicon hydride, for example, the formula: [where RI is hydrogen or an alkyl group or an alkoxy group having 1 to 12 carbon atoms, R2 and R3 are the same or a different alkyl group or alkoxy group having 1 to 12 carbon atoms, X
and y represents a positive integer. ].

The alkyl group is preferably a lower alkyl group such as methyl or ethyl, particularly a methyl group. As the alkoxy group, lower alkoxy groups such as methoxy and ethoxy are preferred.

Substituents for controlling the refractive index of the organic compound (a) include aromatic hydrocarbon groups or fluorine-substituted hydrocarbon groups, such as aromatic hydrocarbon groups such as phenyl, naphthyl, anthryl, and pyrenyl groups. Hydrogen groups and fluorine-substituted alkyl groups, such as trifluoropropyl groups, are preferred.

As the organic compound (a), various organic compounds can be used, for example, the formula: [wherein R4, R5, R8 and R7 represent the same or different substituents, at least one of which has a refractive index ].

It is a compound represented by the following, and is a compound having at least one non-conjugated unsaturated bond.

Examples of the non-conjugated unsaturated bond include a vinyl group, an allyl group, an isopropenyl group, and a vinyl group is particularly preferred.

The hydrosilylation reaction between the organic compound (a) and the siloxane polymer (b) having a silicon-water bond proceeds in the following manner as an organic compound (c) having at least two non-conjugated unsaturated bonds. For example, those represented by the following formula having a vinyl group at the side chain or chain end can be used.

CH,=CH-~＾翳CH=CI-1t (II
I) cH=cttt (However, ~ ~ - 8: Hegaku Structure Department) For example, CH! =CHS i -OS I CH= CH
! CH3CH3 Further, as the organic compound (c), for example, the formula: [wherein R5-R18 are substituents other than vinyl group. ] Examples include siloxane polymers having a vinyl group at the terminal or side chain represented by the following. Examples of the substituent include an alkyl group such as a methyl group and an ethyl group, an alkoxy group, and a cyano group.

Further, the organic compound (c) may be any compound having two or more non-conjugated unsaturated bonds, such as the following.

That is, the organic compound (c) may have at least two or more non-conjugated unsaturated bonds that can cause a hydrosilylation reaction with silicon hydride, and may also have siloxane units and control the refractive index. It may contain a substituent for.

Next, crosslinking by hydrosilylation reaction proceeds as shown in the diagram below.

G Ht = CH Ran~-CH= CI-I t+26
iSiH =Si-CHtCI-1t~ψ^CHtCHtSi
=Crosslinking is carried out between organic compound (a) and siloxane polymer (b).
) may be carried out after the completion of the hydrosilylation reaction with (c), or the organic compound (c) may be present during the hydrosilylation reaction so that both hydrosilylation reactions are carried out competitively.

■, Crosslinked siloxane polymer (B) Siloxane polymer with non-conjugated unsaturated bonds (e)
For example, the formula: [wherein R'7 is a substituent having a non-conjugated unsaturated bond,
R", R" and R" are the same or different and have 1 to 1 carbon atoms
The alkyl group or alkoxy group of 2, X and y represent positive integers. ] It is a compound shown by.

Examples of the substituent having a non-conjugated unsaturated bond include a vinyl group, an allyl group, an isopropenyl group, and a vinyl group is particularly preferred.

The alkyl group is preferably a lower alkyl group such as a methyl group or an ethyl group, particularly a methyl group. As the alkoxy group, lower alkoxy groups such as methoxy and ethoxy are preferred.

Further, both ends are preferably blocked with a substituent having a non-conjugated unsaturated bond such as a vinyl group.

Examples of the silane compound having at least one silicon hydride (d) having a substituent for controlling the refractive index include phenyldimethylsilane, diphenylmethylsilane, phenylsilane, diphenylsilane, methylphenylsilane, p-bis(dimethylsilyl)benzene,
Examples include triphenylsilane, bis[(p-dimethylsilyl)phenyl ether, and cyclohexyldimethylsilane.

Among the siloxane compounds having at least one silicon hydride (d), those having a substituent for controlling the refractive index include low molecular weight compounds such as 1,3-diphenyl-1,3-dimethyldisiloxane. In addition to these, siloxane polymers such as those described below may also be used.

That is, a siloxane polymer having silicon hydride represented by formula (1) and at least one non-conjugated unsaturated bond represented by formula (I[) and having a substituent for controlling the refractive index. This is a siloxane polymer in which the substituent is introduced into the side chain of the siloxane polymer through a hydrosilylation reaction with an organic compound, and a portion of the silicon hydride of the siloxane polymer remains unreacted.

(d) a silane compound or siloxane compound having at least one silicon hydride and having a substituent for controlling the refractive index; and (e) a siloxane polymer having a non-conjugated unsaturated bond. The hydrosilylation reaction is
For example, proceed as shown below.

→□S+-~MNSi-w--- to Si-i m-CHt
CH= CHt CHt(I S t=g S IEiig where g represents a chemical structure having a substituent for controlling the refractive index. Through the hydrosilylation reaction shown in the above figure, a siloxane having a non-conjugated unsaturated bond is formed. Substituents can be introduced into the side chains of the polymer to control the refractive index.

Next, crosslinking by a hydrosilylation reaction between the siloxane compound or silane compound (f) having at least two silicon hydrides and the unreacted siloxane polymer having a non-conjugated unsaturated bond is carried out, for example, as follows. proceed.

G φ■Si-%MS　1-AA-9i≠鴫CH=CHt +HS 1-N-9iH CH-CHt Love-9t-9i-Si-1 G ↓ G Si　　Stφ-9i- CH! Ht Si Si CH.

Ht 輼S1輌S i -S i -G Here, G represents a chemical structure having a substituent for controlling the refractive index introduced into the side chain by a hydrosilylation reaction.

Crosslinking may be carried out after the completion of the hydrosilylation reaction between the siloxane compound or silane compound (d) and the siloxane polymer (e), or the siloxane compound or silane compound (r) may be allowed to coexist during the hydrosilylation reaction, so that both The hydrosilylation reaction may be carried out competitively.

Silane compounds having at least two silicon hydrides (
Examples of r) include dimethylsilane, methylsilane, and tetrakis(dimethylsiloxy)silane. Further, as long as it contains at least two silicon hydrides, it may be selected from the silane compounds listed above as the silane compound (d).

The siloxane compound (r) having at least two silicon hydrides may be a siloxane polymer represented by the formula (1) in addition to 1.1.3.3-tetramethyldisiloxane. Further, as long as it has at least two silicon hydrides, it may be selected from the siloxane polymers exemplified as the siloxane compound (d) described above.

Typically, siloxane or silane compounds with at least two silicon hydrides (primarily for crosslinking) are used.
The combined use of r) and a silane compound or siloxane compound (d) having a substituent for controlling the refractive index and having at least one silicon hydride improves refractive index control and elastic modulus (network density). Favorable results can be obtained from both control points of view.

However, as long as there are two or more silicon hydride bonds, the siloxane compound (d) and the silane compound (d) may be the same as the siloxane compound (f) and the silane compound (f).

The crosslinked siloxane polymers (A) and (B) have been described above. That is, through the hydrosilylation reaction, a substituent for controlling the refractive index can be introduced into the side chain of the siloxane polymer, and crosslinking of the siloxane polymer can also proceed, so that crosslinked siloxane polymers with different refractive indexes can be easily produced. can be obtained. By using such a siloxane polymer, it is possible to obtain an optical waveguide whose refractive index is varied over a wide range with high precision.

[Effects of the Invention] According to the present invention, it is possible to obtain an optical waveguide made of a crosslinked siloxane polymer in which a substituent for controlling the refractive index is introduced into the siloxane polymer through a hydrosilylation reaction. In other words, such a cross-linked siloxane polymer allows the refractive index of the optical waveguide to be varied with high precision and over a wide range, making it easy to match the refractive index when bonding to other optical elements, optical devices, etc. Therefore, good bonding characteristics can be obtained.

If an optical waveguide is made using a crosslinked siloxane polymer in which a substituent that reduces the refractive index, such as a trifluoropropyl group, is introduced into the cladding, and a substituent that increases the refractive index, such as a naphthyl group, is introduced into the optical waveguide, the aperture The optical waveguide can be made into a high-strength optical waveguide, which is suitable for bonding with a light emitting element. In addition, since an optical waveguide with a large aperture can have a small optical radius of curvature, it can be an optical waveguide that takes full advantage of the flexibility of the crosslinked siloxane polymer.

The siloxane polymers according to the invention are also easy to process since they are liquid prior to crosslinking. For this reason, for example, F
After inserting an image fiber into an EP (tetrafluoroethylene/hexafluoropropylene copolymer) tube, the siloxane polymer of the present invention can be injected as a light guide for illumination and cured to form an integrated composite optical waveguide. .

Since siloxane polymers have excellent heat resistance, it is possible to obtain optical waveguides that are more heat resistant than optical waveguides made of other plastic optical materials.

Example [Example 1] (Mv=2900, n♂'=1.3990) 1.2g
, 2.4 g of 2-vinylnaphthalene were each dissolved in 10 ml of chloroform, and both solutions were mixed.

Add chloroplatinic acid/methanol solution (concentration) to this mixture.

4.72 x 10-'M)l 0ml was added to the test tube, mixed well, and reacted at 70°C for 73 hours.

The reaction product was precipitated with methanol, then dissolved again in toluene, and precipitated with methanol to obtain a clear liquid.

1 g of this liquid, 1,3.5-trivinyl-1,1°3
．． 5.5-pentamethyltrisiloxane 0.1 g.

Isopropyl alcohol solution of chloroplatinic acid (3,8x
I O-'M)0.1- was mixed well, and F with an inner diameter of 2 mm was
Injected into a tube of EP (n = 1.338) and incubated at 50 °C.
An optical waveguide was obtained by reaction-curing for 24 hours. This cured product (optical waveguide) was transparent, and its refractive index at 20° C. was measured to be 1.593. The aperture of this optical waveguide was calculated to be 0.86.

[Example 2] (Mw = 2920, n♂0 = 1.3990) 3g1 (Mw = 23800, n,” = 1.4053) 5g
and 3 g of styrene, and 0.15 m of a solution of chloroplatinic acid in isopropyl alcohol (3,8xlO'''''M)
Q was mixed well, and the mixture was reacted and cured at 60° C. for 3 hours in the same manner as in Example 1 to obtain an optical waveguide. This cured product (optical waveguide)
is transparent, and when its refractive index was measured at 20°C, it was 1
．． It was 462.

[Example 3] (Mw = 2900, n♂' = 1.3990) 2 g 1 divinylbenzene 4.7 g, isopropyl alcohol solution of chloroplatinic acid (3,8 x l O-3M) 0, 1 m
Mix Q well, inject into a tube of transparent silicone rubber (n=1.41) with an inner diameter of 2 ml, and incubate at 50°C for 24 hours.
An optical waveguide was obtained by time reaction curing. This cured product was transparent, and the refractive index at 20°C was 1.46.
It was 9.

[Example 4] (Mw=4700, ff=32.2%, n♂0=1.
4 o t s > 2, Ogs divinylbenzene 0.66 g, isopropyl alcohol solution of chloroplatinic acid (3,8X10-'M
) 0.1 m12 well mixed and prepared in the same manner as in Example 3.
An optical waveguide was obtained by reaction-curing at 0° C. for 6 hours. This cured product (optical waveguide) was transparent, and its refractive index at 20° C. was measured to be 1.455.

[Example 5] (Mw=9900, (2m3%, n♂'=1.404
8) 3,0 g, divinylbenzene 0.17 g1 isopropyl alcohol solution of chloroplatinic acid (3,8xl O
-'M) Mix well 0.1mf2, Example! In the same manner as above, reaction and curing was carried out at 50° C. for 2.5 hours to obtain an optical waveguide.

This cured product was transparent, and its refractive index at 20°C was measured to be 1.413.

[Example 6] (Mw=624QO1k=19.3%, n♂'=1.4
13) 2.0 g, 1.0 g of polymer (5) used in Example 4
Phenyldimethylsilane 1. Og, isopropyl alcohol solution of chloroplatinic acid (3,8X 10-'M) 0.1
mf2 was mixed well and heated to 1 at 70°C in the same manner as in Example 1.
An optical waveguide was obtained by time reaction curing. This cured product was transparent, and the refractive index at 20°C was 1.421.
Met.

[Example 7 (Mw = 6000, p = 42.4%, Q = 25.6%
mouth. ”=1.501) 1.0 g, and 2.0 g of the polymer (7) used in Example 6.

Phenyldimethylsilane l, Og, isopropyl alcohol solution of chloroplatinic acid (3,8X10-'M) 0.
1m (2) were thoroughly mixed and reacted and cured at 70°C for 1 hour in the same manner as in Example 1 to obtain an optical waveguide. This cured product was transparent, and when the refractive index at 20°C was measured, it was found to be 1. 42
It was 9.

Example 8] (Mw=132200.5=24.2%, no"=1
．． 416) 2, Og, phenylsilane 0,9 g, isopropyl alcohol solution of chloroplatinic acid (3,8X IO-
'M)0 and 1 mQ were thoroughly mixed and reacted and cured in the same manner as in Example 1 at 100°C for 1 hour to obtain an optical waveguide.

When the refractive index of this cured product was measured at 20°C, it was found to be 1.
It was 437.

[Example 9] 5.0 g of polymer (5) used in Example 4, CH*=C
HC4F e 1, Og, isopropyl alcohol solution of chloroplatinic acid (3,8XIO-'M) O, 1m12
were mixed well and subjected to a hydrosilylation reaction at 50° C. for 3 hours in an ampoule. The product was precipitated with methanol, collected and dried. Next, 0.2 g of this obtained liquid material
, 1.0 g of the polymer (7) used in Example 6, an isopropyl alcohol solution of chloroplatinic acid (3,8X l O-
'M)0.05- were mixed well and subjected to hydrosilylation reaction at 50°C for 3 hours.

Furthermore, 0.05 g of 1,1,3,3-tetramethylsiloxane was added to this, and the same procedure as in Example 1 was carried out at 70°C.
The mixture was reacted and cured for 1 hour to obtain an optical waveguide.

This cured product was transparent, and its refractive index at 20° C. was measured to be 1.403.

[Example 101 2.5 g of polymer (5) used in Example 4, 0.5 g of 9-vinylanthracene,) 3 ff1Q of toluene, isopropyl alcohol solution of chloroplatinic acid (3,8X10-3
M) 0.05ma mixed well and heated at 50℃ in an ampoule for 3
It was subjected to a hydrosilylation reaction for an hour. The product was precipitated with methanol, collected and dried.

Next, 0.1 g of this obtained liquid, 1.0 g of the polymer (7) used in Example 6, 0.1 g of the polymer (5) used in Example 4, and an isopropyl alcohol solution of chloroplatinic acid. (3,8X 10"-'M) 0.05m1
2 were mixed well, and the mixture was reacted and cured in the same manner as in Example 1 at 70° C. for 1 hour to obtain an optical waveguide. This cured product is transparent and
When the refractive index at 0° C. was measured, it was 1.416.

[Example 11] 10) (Mw=66800, k=28.9%, n1ll''=
1.402) 2,7 g, divinylbenzene 0,2 g, isopropyl alcohol solution of chloroplatinic acid (3,8xlO''''
"M) 0.01 mf2 was thoroughly mixed and defoamed. This mixture was injected into an F'EP tube having an outer diameter of 2 mn+ and an inner diameter In+m.

The mixture was left to stand at room temperature for 5 days to harden and obtain an optical waveguide. When we measured the transmission loss of this optical waveguide, we found that it was 8 dB/
It was m. In addition, when the refractive index of this cured product was measured at 20°C, it was 1.404.

[Example 12] 1.0 g of polymer (3) used in Example 2 Example 11
3.0g of polymer (10) used in , 2.0g of styrene
and isopropyl alcohol solution of chloroplatinic acid (3,
8x 10-'M) 0.01 mf2 was mixed well and defoamed. An optical waveguide was obtained using this mixture in the same manner as in Example 11, and the transmission loss was measured to be 2 dB/m.

The refractive index of this cured product at 20° C. was measured and found to be 1.408.

[Example 13] The polymer used in Example 4 (5N, 5 g, the polymer (9) used in Example 8, 3.0 g, phenyldimethylsilane, 5 g, and a solution of chloroplatinic acid in isopropyl alcohol (3.8 x 10 -'M) 0.05 mf2 was thoroughly mixed and defoamed. An optical waveguide was obtained from this mixture in the same manner as in Example 11, and the transmission loss was measured, and it was found to be 1 odB
/+++. The refractive index of this cured product at 20° C. was measured and found to be 1.420.

[Example 14 10.0 g of polymer (5) used in Example 4, CH,=
CHC, Fe 2. 0.2 ml of an isopropyl alcohol solution (3,8×10-'M) of Og and chloroplatinic acid were mixed well and subjected to a hydrosilylation reaction at 50° C. for 3 hours in a beaker. The product was precipitated with methanol, collected and dried. Next, 0.4 g of the polymer (3) used in Example 2 and an isopropyl alcohol solution of chloroplatinic acid (3.8 x 10-3 M
) 0.05 m (added, mixed, and defoamed. An optical waveguide was obtained from this mixture in the same manner as in Example 11, and the transmission loss was measured to be 4 dB/m. When the refractive index at °C was measured, it was 1.402.

[Example 15 5.0 g of polymer (5) used in Example 4.

CHt=CHC, Fs 1. Og, isopropyl alcohol solution of chloroplatinic acid (3,8xl O-'M) O,1
m12 was mixed well and subjected to a hydrosilylation reaction at 50° C. for 3 hours in a beaker. The product was precipitated with methanol, collected and dried. Next, this obtained liquid material t,
Qg, 3.0 g of polymer (9) used in Example 8, 1
．． 0.1 g of 1,3,3-tetramethyldisiloxane and a solution of chloroplatinic acid in isopropyl alcohol (3,8X
10-3M) was added, and after mixing, defoaming was performed. An optical waveguide was obtained from this mixture in the same manner as in Example 11, and the transmission loss was measured to be 5 dB/m.

The refractive index of this cured product at 20° C. was measured and found to be 1.400.

[Example 1B] 5.0 g of polymer (5) used in Example 4 CHt=C
HC, Fs 1. 1 ml of an isopropyl alcohol solution of Og and chloroplatinic acid (3,8X 1 O-'M)O were mixed well and subjected to a hydrosilylation reaction at 50° C. for 3 hours in a beaker. The product was precipitated with methanol, collected and dried. The obtained liquid material is referred to as A.

On the other hand, 2.0 g of the polymer (5) used in Example 4, styrene T, Og, and 0.05 mg of isopropyl alcohol solution layer of chloroplatinic acid (3,8X l O-'M) were mixed well and placed in a beaker. The mixture was subjected to a hydrosilylation reaction at 50°C for 31 hours. The product was precipitated with methanol, collected and dried. The obtained liquid material is designated as B.

Next, liquid substance A1. Og, the Bo! used in Example 8!
J? -(9)3. Og, liquid B O, 1g Oyohi isopropyl alcohol solution of chloroplatinic acid (3.8
""3M) 0, 0.5 mQ was added, and after mixing, defoaming was performed.

An optical waveguide was obtained from this mixture in the same manner as in Example 11,
When the transmission loss was measured, it was 5 dB/m. In addition, when the refractive index at 20'C of this cured product was measured,
It was 1.406.

[Example 17] The uncrosslinked polymer obtained in the same manner as in Example 9 was coated on a plastic film, reacted and cured at 70° C. for 1 hour to form a cladding layer, and the Example! An uncrosslinked polymer obtained in the same manner as above was applied and cured by reaction at 50° C. for 24 hours to form an optical waveguide.

Furthermore, an uncrosslinked polymer obtained in the same manner as in Example 9 was applied on top of the cladding layer and cured at 70'C for 1 hour to form a cladding layer. A planar optical waveguide was obtained.

Claims (1)

[Claims] 1. An optical waveguide consisting of a cladding and an optical waveguide, characterized in that at least the optical waveguide is made of a crosslinked siloxane polymer into which a substituent for controlling the refractive index is introduced by a hydrosilylation reaction. optical waveguide. 2. The crosslinked siloxane polymer is produced by a hydrosilylation reaction between (a) an organic compound having at least one non-conjugated unsaturated bond and a substituent for controlling the refractive index, and (b) a siloxane polymer having silicon hydride. A siloxane polymer having the substituent introduced into the side chain is combined with silicon hydride in the siloxane polymer that remains unreacted in the hydrosilylation reaction, and (c) an organic compound having at least two non-conjugated unsaturated bonds. The optical waveguide according to claim 1, which is a crosslinked siloxane polymer crosslinked by a hydrosilylation reaction with. 3. The optical waveguide according to claim 2, wherein the substituent for controlling the refractive index of the organic compound (a) is an aromatic hydrocarbon group. 4. The optical waveguide according to claim 2, wherein the substituent for controlling the refractive index of the organic compound (a) is a fluorine-containing hydrocarbon group. 5. The light guide according to any one of claims 2 to 4, wherein the organic compound (c) has at least two non-conjugated unsaturated bonds and has a substituent for controlling the refractive index. wave path. 6. The optical waveguide according to any one of claims 2 to 4, wherein the organic compound (c) has at least two nonconjugated unsaturated bonds and has a siloxane unit. 7. Any one of claims 2 to 4, wherein the organic compound (c) has at least two non-conjugated unsaturated bonds, and has a substituent and a siloxane unit for controlling the refractive index. The optical waveguide described. 8. The optical waveguide according to any one of claims 2 to 7, wherein the organic compound (a) and the organic compound (c) are the same compound. 9. The crosslinked siloxane polymer contains (d) a siloxane compound or silane compound having at least one silicon hydride and a substituent for controlling the refractive index;
) The siloxane polymer in which the substituent has been introduced into the side chain by a hydrosilylation reaction with a siloxane polymer having a non-conjugated unsaturated bond is treated with the non-conjugated unsaturation in the siloxane polymer that remains unreacted in the hydrosilylation reaction. The optical waveguide according to claim 1, which is a crosslinked siloxane polymer crosslinked by a hydrosilylation reaction between a bond and (f) a siloxane compound or a silane compound having at least two silicon hydrides. 10. The siloxane compound (d) is a hydrosilylation reaction between a siloxane polymer having silicon hydride and an organic compound having at least one non-conjugated unsaturated bond and a substituent for controlling the refractive index, The optical waveguide according to claim 9, which is a siloxane polymer in which the substituent is introduced into the side chain of the siloxane polymer. 11. The siloxane compound (f) is a hydrosilylation reaction between a siloxane polymer having silicon hydride and an organic compound having at least one non-conjugated unsaturated bond and a substituent for controlling the refractive index, The optical waveguide according to claim 9 or 10, which is a siloxane polymer having the substituent introduced into the side chain of the siloxane polymer. 12. The optical waveguide according to any one of claims 9 to 11, wherein the substituent for controlling the refractive index is an aromatic hydrocarbon group. 13. The optical waveguide according to any one of claims 9 to 11, wherein the substituent for controlling the refractive index is a fluorine-containing hydrocarbon group. 14. The light guide according to any one of claims 9 to 13, wherein the siloxane compound or silane compound (f) has at least two silicon hydrides and has a substituent for controlling the refractive index. wave path. 15. The optical waveguide according to claims 9 to 14, wherein the siloxane compound or silane compound (d) and the siloxane compound or silane compound (f) are the same compound.