JP2000017176A - Silicone composition for optical use and lens - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a silicone composition suitable as an optical material having excellent transparency, a high refractive index and a small double refraction and a lens. SOLUTION: This silicone composition for optical use and a lens comprises (A) an organopolysiloxane of the general formula Ra(R1)2SiO[(R2)2SiO]nSi(R1)2Ra [Ra is an alkenyl group; R1 and R2 are each an alkyl group, a cycloalkyl group or an aryl group; (n) is an integer of >=30], (B) an organopolysiloxane composed of siloxane units of the formula Rb(R3)2SiO0.5, (R4)3SiO0.5, R5SiO1.5 (Rb is an alkenyl group; R3, R4 and R5 are each an alkyl group, a cycloalkyl group or an aryl group) and SiO2, (C) an organohydrogenpolysiloxane containing at least two hydrogen atoms bonded to Si in which an organic group R6 bonded to Si in the molecule is shown by an alkyl group, a cycloalkyl group or an aryl group (>=5 mol.% of organic group of the total of the groups R1 to R6 is a cycloalkyl group) and (D) a platinum-based catalyst.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical silicone composition which provides a cured product useful as an optical material such as a lens, an optical element coating material, an optical fiber matching material, and a core material.

[0002]

2. Description of the Related Art An optical plastic material is required to have high transparency and a high refractive index, and an optical lens is required to have low birefringence.

Conventionally, polymethyl methacrylate, polycarbonate, and the like have been used to meet these requirements. However, these materials do not have sufficient heat resistance, and are deformed or discolored over time at high temperatures. Further improvement in heat resistance has been required.

[0004] To meet these requirements, silicone resins have attracted attention. For example, JP-A-8-134358 discloses that a) a linear organopolysiloxane having both ends blocked with a vinyl group and containing a phenyl group as an organic group;
b) CH ₂ ＣＨCH (CH ₃ ) ₂ SiO _0.5 , (CH ₃ ) ₃ Si
O _0.5 , PhSiO _1.5 (Ph represents a phenyl group) and an SiO ₂ unit, an organopolysiloxane copolymer, c) an organohydrogenpolysiloxane having a hydrogen atom bonded to a silicon atom, and d) a platinum compound And the use of a silicone composition which gives a transparent cured product has been proposed.

[0005]

However, it has been found that the above-mentioned known silicone composition can provide a cured product having good transparency, but still has a low refractive index and a large birefringence.

[0006] Therefore, an object of the present invention is to provide excellent transparency.
An object of the present invention is to provide a silicone composition suitable as an optical material from which a cured product having a high refractive index and a small birefringence can be obtained.

[0007]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above problems, and as a result, have found the following composition, and in particular, an optical lens formed by using the composition has been developed. I found it to be excellent.

That is, (A) an organopolysiloxane represented by the following general formula [1], and a general formula [1] R ^a (R ¹ ) ₂ SiO [(R ² ) ₂ SiO] _n Si (R ¹ ) ₂ R
^a wherein R ^a represents an alkenyl group, R ¹ and R ² each represent an alkyl group, a cycloalkyl group, or an aryl group;
n represents an integer of 30 or more], (B) R ^b (R ³ ) ₂ Si
O _0.5 , (R ⁴ ) ₃ SiO _0.5 , R ⁵ SiO _1.5 (however, R ^b
Represents an alkenyl group, and R ³ , R ⁴ and R ⁵ each represent an alkyl group, a cycloalkyl group, or an aryl group. ) And Si
O ₂ siloxane units, and R ₂
^b organopolysiloxane copolymer having a total molar ratio of _0.5 units of (R ³ ) ₂ SiO _0.5 units and _0.5 units of (R ⁴ ) ₃ SiO, and (C) a hydrogen atom bonded to a silicon atom Wherein the organic group R ⁶ bonded to the silicon atom in the molecule is represented by an alkyl group, a cycloalkyl group, or an aryl group, and is an organohydrogen which is compatible with the components (A) and (B). Genpolysiloxane, (however,
R ¹ and R ^{2 of} the component (A), R ^{3 of} the component (B),
At least one of R ⁴ and R ⁵ and R ⁶ of the component (C);
One represents a cycloalkyl group, and R ¹ , R ² , R ³ , R ⁴ , R
⁵ and at least 5 mol% of the total organic groups of R ⁶ are cycloalkyl groups) and (D) a platinum-based catalyst.

In the present invention, the organopolysiloxane copolymer represented by the formula (B) may further comprise MO _X units (where M is in the fourth to sixth periods belonging to groups 2A to 5A of the periodic table). X is an atom selected from the group of atoms and includes all lanthanide-series atoms, and X varies depending on the valence of the selected atom and takes any value of 1, 1.5, 2.0, and 2.5. ) Is provided.

Further, the present invention provides an optical silicone lens formed from the optical silicone composition.

Hereinafter, the present invention will be described in detail.

(A) Alkenyl Group-Containing Linear Organopolysiloxane The component (A) constituting the composition of the present invention is represented by the above general formula [1] and has a linear structure having alkenyl groups at both terminals of the molecule. It is an organopolysiloxane. Examples of the alkenyl group bonded to the silicon atom of the organopolysiloxane include a vinyl group, an isopropenyl group, an allyl group, and a butenyl group, and a vinyl group is preferable. Organic groups other than alkenyl groups bonded to silicon atoms in the organopolysiloxane are alkyl groups, cycloalkyl groups, and phenyl groups.

Examples of the alkyl group include substituted and unsubstituted alkyl groups such as a methyl group, an ethyl group, a propyl group, a butyl group, a benzyl group, a phenethyl group, a chloropropyl group and a trifluoropropyl group. Group. Examples of the cycloalkyl group include a cyclopentyl group, a cyclohexyl group, an adamantyl group, and a norbornyl group, and a cyclohexyl group is preferable. Examples of the aryl group include phenyl, tolyl, xylyl, naphthyl, chlorophenyl, furyl, thienyl, pyridyl and the like, with phenyl being preferred. In the general formula [1], n that reflects the degree of polymerization is an integer of 30 or more, preferably 100 or more. When n is less than 30, the flexibility of the obtained cured product may be reduced and the cured product may be brittle. The following are examples of the organopolysiloxane.

AU-1 ViMe ₂ SiO— (Me ₂ Si
O) _i (MePhSiO) _m (Ph ₂ SiO) _n (Cy ₂ S)
iO) _o (MeCySiO) _p (PhCySiO) _q -S
iMe ₂ Vi AU-2 ViMePhSiO- (Me ₂ SiO) _i (M
ePhSiO) _m (Ph ₂ SiO) _n (Cy ₂ SiO)
_o (MeCySiO) _p (PhCySiO) _q -SiMe
PhVi AU-3 ViPh ₂ SiO- (Me ₂ SiO) _i (Me
PhSiO) _m (Ph ₂ SiO) _n (Cy ₂ SiO) _o (M
eCySiO) _p (PhCySiO) _q -SiPh ₂ Vi AU-4 ViCy ₂ SiO- (Me ₂ SiO) _i (Me
PhSiO) _m (Ph ₂ SiO) _n (Cy ₂ SiO) _o (M
eCySiO) _p (PhCySiO) _q -SiCy ₂ Vi AU-5 ViMeCySiO- (Me ₂ SiO) _i (M
ePhSiO) _m (Ph ₂ SiO) _n (Cy ₂ SiO)
_o (MeCySiO) _p (PhCySiO) _q -SiMe
CyVi AU-6 ViPhCySiO- (Me ₂ SiO) _i (M
ePhSiO) _m (Ph ₂ SiO) _n (Cy ₂ SiO)
_o (MeCySiO) _p (PhCySiO) _q -SiPh
CyVi AU-7 ALMe ₂ SiO- (Me ₂ SiO) _i (Me
PhSiO) _m (Ph ₂ SiO) _n (Cy ₂ SiO) _o (M
eCySiO) _p (PhCySiO) _q -SiMe ₂ AL AU-8 IPMePhSiO- (Me ₂ SiO) _i (M
ePhSiO) _m (Ph ₂ SiO) _n (Cy ₂ SiO) _o (Me
CySiO) _p (PhCySiO) _q -SiMePhIP (however, Vi is a vinyl group, AL is an allyl group, IP is an isopropenyl group, Me is a methyl group, Ph is a phenyl group,
y represents a cycloalkyl group. i, m, n, o, p, q
Is an integer of 0 or more, and any one of them represents an integer of 1 or more. In the exemplary compounds of the component (A), at least one of o, p, and q is preferably an integer of 1 or more.

The organopolysiloxane of the component (A) can be produced by equilibrating a disiloxane containing a desired terminal group with a cyclic organopolysiloxane having a desired organic group in the presence of an alkali catalyst.

(B) Branched alkenyl group-containing organopolysiloxane The component (B) is a component for increasing the strength and hardness of the obtained cured product, and is composed of R ^b (R ³ ) ₂ SiO _0.5 and (R ⁴ ) ₃ Si
O _0.5 , R ⁵ SiO _1.5 (where R ^b represents an alkenyl group, and R ³ , R ⁴ and R ⁵ each represent an alkyl group, a cycloalkyl group or an aryl group) and a SiO ₂ siloxane unit, R ^b (R ³ ) ₂ SiO with respect to SiO ₂ unit
_0.5 units and (R ⁴⁾ ₃ the total molar ratio of SiO _0.5 units 0.
5 to 2.0, preferably 0.6 to 1.2.
Those less than 0.5 are substantially difficult to produce,
If it is larger, the strength and hardness of the obtained cured product may not be increased.

R ^b represents an alkenyl group, and specific examples thereof include the same alkenyl groups as those described for R ^a in the component (A).

R ³ , R ⁴ and R ⁵ each represent an alkyl group,
It represents a cycloalkyl group or an aryl group, and specific examples of the alkyl group, the cycloalkyl group and the aryl group are the same as the examples of the alkyl group, the cycloalkyl group and the aryl group described in the component (A). R ⁵ is preferably a cycloalkyl group.

The R ⁵ SiO _1.5 unit is preferably contained so that at least 5 mol% of all organic groups bonded to silicon atoms in the organopolysiloxane are cycloalkyl groups. At this time, the content of the cycloalkyl group of the organopolysiloxane of the component (B) should be as similar as that of the component (A) so that good compatibility with the component (A) can be obtained. Is preferred.

If the content of alkenyl group in the organopolysiloxane (B) is too small, it is necessary to increase the amount of this component, which is uneconomical. Therefore, the content is preferably in the range of 0.5 to 5.0% by weight. The content of the organopolysiloxane (B) is preferably from 10 to 50% by weight based on the total weight of the composition. If the content is too small, the hardness and strength of the cured product will not be sufficiently improved, and if it is too large, elongation will be small and flexibility will be reduced.

The organopolysiloxane of the component (B) is
It can be produced by a known method of mixing and hydrolyzing a halosilane or an alkoxysilane corresponding to each constituent siloxane unit.

Furthermore, in order to achieve a high refractive index, it is preferred to introduce the MO _X units in component (B). here,
M is an atom selected from the group of atoms in the fourth to sixth periods belonging to the periodic table 2A to 5A, and includes all lanthanide series atoms. Among them, M, Ba, Sc, L
Atoms such as a, Ti, Nb, and Ta are also excellent in transparency and are more preferable. M may be used alone or in combination of two or more. X varies with the valence of the selected atom, and
It takes one of 5, 2.0, and 2.5.

The amount of MO _X introduced can be adjusted in the range of 0.01 to 4 in terms of the ratio to the SiO ₂ unit, but is more preferably in the range of 0.2 to 2.0.

The above-mentioned organopolysiloxane can be produced by a known method in which an alkoxide of a corresponding element is mixed with a halosilane or an alkoxysilane corresponding to each constituent siloxane unit and co-hydrolyzed.

A specific example will be described below.

BU-1 (ViMe ₂ SiO _0.5 ) _0.081
(Me ₃ SiO _0.5 ) _0.234 (ChSiO _1.5 ) _0.170 (S
iO ₂ ) _0.315 (BaO) _0.200 BU-2 (ViMe ₂ SiO _0.5 ) _0.081 (Me ₃ SiO
_{0.5) 0.269 (ChSiO 1. 5)} 0.100 (SiO 2)
_0.300 (ScO _1.5 ) _0.250 BU-3 (ViMe ₂ SiO _0.5 ) _0.081 (Me ₃ SiO
_0.5 ) _0.249 (ChSiO _1.5 ) _0.120 (SiO ₂ )
_0.250 (LaO _1.5 ) _0.300 BU-4 (ViMe ₂ SiO _0.5 ) _0.081 (Me ₃ SiO
_0.5 ) _0.334 (ChSiO _1.5 ) _0.170 (SiO ₂ )
_0.215 (TiO ₂ ) _0.200 BU-5 (ViMe ₂ SiO _0.5 ) _0.081 (Me ₃ SiO
_0.5 ) _0.204 (ChSiO _1.5 ) _0.150 (SiO ₂ )
_0.250 (NbO _2.5 ) _0.315 BU-6 (ViMe ₂ SiO _0.5 ) _0.081 (Me ₃ SiO
_{0.5) 0.219 (ChSiO 1.5) 0.100} (SiO 2)
_0.250 (TaO _2.5 ) _0.300 BU-7 (ALMe ₂ SiO _0.5 ) _0.081 (Me ₃ SiO
_0.5 ) _0.234 (ChSiO _1.5 ) _0.170 (SiO ₂ )
_0.315 (BaO) _0.200 BU-8 (IPMe ₂ SiO _0.5 ) _0.081 (Me ₃ SiO
_0.5 ) _0.269 (ChSiO _1.5 ) _0.100 (SiO ₂ )
_0.300 (ScO _1.5 ) _0.250 (where, Vi represents a vinyl group, AL represents an allyl group, IP represents an isopropenyl group, Me represents a methyl group, and Ch represents a cyclohexyl group.) (C) Organohydrogenpolysiloxane (C) component Is an organopolysiloxane having at least two hydrogen atoms bonded to silicon atoms. The hydrogen atoms and the alkenyl groups of the components (A) and (B) undergo an addition reaction to form a crosslink and cure the composition. Acts as a cross-linking agent. Therefore, in order to obtain the transparent cured product of the present invention, it is necessary to contain at least two silicon-bonded hydrogen atoms in one molecule, and it is well compatible with the components (A) and (B). It is necessary. Further, in order for the obtained cured product to have sufficient strength and hardness, the content of hydrogen atoms is preferably 0.1 to 2.0% by weight. The amount of the organohydrogenpolysiloxane of the component (C) is preferably such that the number of hydrogen atoms is 0.1 to 5 per alkenyl group in the components (A) and (B). Is from 0.5 to 2.0. The monovalent organic group R ⁶ bonded to silicon contained in the organohydrogenpolysiloxane (C) is an alkyl group, a cycloalkyl group, or an aryl group, and specific examples of the alkyl group, the cycloalkyl group, and the aryl group are as described above ( The same as the examples of the alkyl group, cycloalkyl group and aryl group described in the component (A) can be used.
The structure may be any of a chain, a branched chain, a ring, and a network.

(D) Platinum Catalyst The component (D) is a catalyst for causing an addition reaction between the components (A) and (B) and the component (C). Can be used. For example, platinum black, chloroplatinic acid, a complex of chloroplatinic acid and an olefin, a complex of chloroplatinic acid and an aldehyde, an alcohol-modified chloroplatinic acid, and a siloxane-modified chloroplatinic acid are preferably used. The amount of the platinum-based catalyst used is
(A), (B), (C), and (D) may be appropriately increased or decreased according to the type of each component, a desired curing speed, and the like. However, for practical purposes, it may be in the range of 0.01 to 1000 ppm based on the total weight of the composition of the present invention.

Other Components The composition of the present invention may contain, as a component other than the above-mentioned components (A) to (D), a reaction control agent for controlling the reaction as necessary unless the object of the present invention is impaired. For example, compounds such as phosphorus, nitrogen and sulfur or acetylene compounds may be added.

The components (A) to (D) of the present invention are mixed and cured by any desired method. This composition cures very slowly at room temperature, but is practically 50-150 ° C.
Alternatively, heating to a higher temperature is advantageous. In this way, curing proceeds in a matter of minutes to hours. That is, by adjusting the temperature and the concentration of the platinum catalyst, the curing time can be adjusted over a wide range.

[0030]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

In the following description, Vi represents a vinyl group, Me represents a methyl group, Ph represents a phenyl group, and Ch represents a cyclohexyl group.

Example 1 As shown in Table 1, 80 parts by weight of the component (A), 20 parts by weight of the component (B), and 5.8 parts by weight of the component (C) were mixed. An octyl alcohol-modified solution of chloroplatinic acid was added and mixed such that the platinum content was 0.5 ppm based on the weight of the obtained mixture, and a composition was obtained. All the obtained compositions were transparent. This composition was poured into a mold having a cylindrical space with a diameter of 50 mm and a thickness of 3 mm, and was cured by heating at 150 ° C. for 5 hours. The obtained cured products were all transparent, and the birefringence was measured according to the Senarmont method. Table 1 shows the results.

[0033]

[Table 1]

The components are shown below.

A: The average composition is ViMe ₂ SiO— (Me ₂
SiO) ₁₇₄ (Ph ₂ SiO) ₂₄ —SiMe ₂ Vi Linear organopolysiloxane having vinyl groups at both ends of the molecule b: Average composition is (ViMe ₂ SiO _0.5 ) _0.081 (Me ₃ S
iO _0.5 ) _0.334 (PhSiO _1.5 ) _0.170 (SiO ₂ )
An organopolysiloxane represented by _0.415 c: having a hydrogen atom bonded to a silicon atom and having a degree of polymerization of 3
Methylhydrogenpolysiloxane containing 0% or less of hydrogen atoms and containing 0.7% by weight of hydrogen.
The formulas (2) and (3) and methyl hydrogen polysiloxane described in Example 1 of Examples of JP-A-134358.

A-1: The average composition is ViMe ₂ SiO—
(Me ₂ SiO) ₁₇₄ (Ch ₂ SiO) ₂₄ —SiMe ₂ Vi
A linear organopolysiloxane having vinyl groups at both molecular ends represented by the following formula: B-1: having an average composition of (ViMe ₂ SiO _0.5 ) _0.081 (M
e ₃ SiO _0.5 ) _0.334 (ChSiO _1.5 ) _0.170 (Si
O ₂₎ Organopolysiloxane C-1 represented by _0.415: it has a hydrogen atom bonded to a silicon atom, apparent cyclohexyl hydrogen polysiloxane Table 1 degree of polymerization containing 0.7 wt% hydrogen below 30 Thus, it can be seen that the optical silicone composition of the present invention can provide a cured product suitable as an optical material that is required to have low birefringence.

Example 2 Sample No. 1 of Example 1 A cured product was obtained in exactly the same manner as in Example 1 except that the component (B) of No. 4 was changed to that shown in Table 2, and then the birefringence and the refractive index were measured. Further, the sample No. of Example 1 was used. 7 was also measured for birefringence and refractive index in the same manner.
Table 2 shows the results. Note BU-2, 3, 5 and 6 is obtained by introducing MO _X units for high refractive index as described above.

[0038]

[Table 2]

From the results shown in Table 2, it can be seen that by changing the component (B), a low birefringence can be maintained and the refractive index can be further increased.

[0040]

According to the present invention, a silicone cured product having excellent transparency, high refractive index, and small birefringence can be obtained.

Continuation of the front page (72) Inventor Hide Hosoe 2970, Ishikawacho, Hachioji-shi, Tokyo Konica Corporation F-term (reference) 2H036 MA00 4J002 CP03X CP04Y CP12W DA116 DE176 FD146 GP00

Claims (3)

[Claims] (A) An organopolysiloxane represented by the following general formula [1], and a general formula [1] R ^a (R ¹ ) ₂ SiO [(R ² ) ₂ SiO] _n Si (R ¹ ) ₂ R
^a wherein R ^a represents an alkenyl group, R ¹ and R ² each represent an alkyl group, a cycloalkyl group, or an aryl group;
n represents an integer of 30 or more], (B) R ^b (R ³ ) ₂ Si
O _0.5 , (R ⁴ ) ₃ SiO _0.5 , R ⁵ SiO _1.5 (however, R ^b
Represents an alkenyl group, and R ³ , R ⁴ and R ⁵ each represent an alkyl group, a cycloalkyl group, or an aryl group. ) And Si
O ₂ siloxane units, and R ₂
^b organopolysiloxane copolymer having a total molar ratio of _0.5 units of (R ³ ) ₂ SiO _0.5 units and _0.5 units of (R ⁴ ) ₃ SiO, and (C) a hydrogen atom bonded to a silicon atom Wherein the organic group R ⁶ bonded to the silicon atom in the molecule is represented by an alkyl group, a cycloalkyl group, or an aryl group, and is an organohydrogen which is compatible with the components (A) and (B). Genpolysiloxane, (however,
R ¹ and R ^{2 of} the component (A), R ^{3 of} the component (B),
At least one of R ⁴ and R ⁵ , and R ⁶ of the component (C);
One represents a cycloalkyl group, and R ¹ , R ² , R ³ , R ⁴ , R
⁵ and at least 5 mol% of the total organic groups of R ⁶ are cycloalkyl groups) and (D) a platinum-based catalyst. 2. The organopolysiloxane copolymer represented by (B) further comprises MO _X units (where M is the periodic table 2A).
It is an atom selected from the group of atoms belonging to the 4th to 6th periods belonging to the 〜5A group, and includes all lanthanide series atoms. X varies depending on the valence of the selected atom, and is 1, 1.5, 2,.
2. The optical silicone composition according to claim 1, wherein the composition has a value of 0 or 2.5). 3. An optical silicone lens formed from the optical silicone composition according to claim 1.