JPH0643302A - Optical components - Google Patents

Abstract

(57) [Summary] [Objective] To provide an optical component having a small birefringence and a high adhesion of an antireflection film. An optical component in which an antireflection film is provided on the surface of a base material made of polycarbonate, polyester carbonate, or polyester having a norbornane skeleton, a dimethanoperhydronaphthalene skeleton or a trimethanoperhydroanthracene skeleton.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to optical components.

[0002]

2. Description of the Related Art Various transparent resins are used for optical parts such as optical lenses, spectacle lenses, optical disk substrates, plastic optical fibers and diffraction gratings. Examples of such optical components include a lens for pickup of an optical disc, an aspherical lens used as a lens for a camera, a lens for image projection, etc., a diffraction grating used for splitting a laser beam in a pickup of an optical disc, a solid-state imaging device. There is an optical low-pass filter provided in the optical system for removing the false signal of the element.

As a resin for such an optical component, polymethylmethacrylate (hereinafter referred to as PMMA),
Polyacrylate type copolymers, bisphenol A type polycarbonates (hereinafter referred to as PC), etc. are mainly used. Further, for the purpose of increasing the amount of transmitted light and eliminating stray light, an antireflection film made of an inorganic dielectric material or the like may be formed on the light incident surface and the emission surface of the optical component.

[0004]

However, PMMA and polyacrylate type copolymers have a relatively large water absorption, so that dimensional changes occur due to moisture absorption, and not only optical characteristics change but also antireflection. The film may crack and peel. Further, PC has a large birefringence and lacks surface hardness, so that its use is limited.

An object of the present invention is to provide an optical component having a small birefringence and a high antireflection film adhesion.

[0006]

The above object of the present invention is to provide an antireflection film on the surface of a substrate made of a polycarbonate, polyester or polyester carbonate having a norbornane skeleton, a dimethanoperhydronaphthalene skeleton or a trimethanoperhydroanthracene skeleton. Is provided.

That is, the present invention provides the following general formulas (I) to (III)

[Chemical 4] Of the structural units (I) to (III), and the molar fraction (x) of the structural unit (I) is the structural unit (I).
A base material made of a resin substantially equal to the total mole fraction (y + z) of the mole fraction (y) of I) and the mole fraction (z) of the structural unit (III), the above structural units (I) and ( II) and the molar fraction (x) of the structural unit (I) is
A base material made of a resin that is substantially equal to the mole fraction (y) of I), or the above structural units (I) and (III),
An antireflection film is provided on the surface of a base material made of a resin in which the molar fraction (x) of the structural unit (I) is substantially equal to the molar fraction (z) of the structural unit (III). It is an optical component.

In the resin of the present invention, the molar fraction (x) of the structural unit (I) represented by the general formula (I) is about 50 mol%.
Is. The molar fraction (y) of the structural unit (II) represented by the general formula (II) is in the range of 50 mol% or less, preferably 40 mol% or more and 50 mol% or less.
If the content is less than 20 mol%, the water absorption may not be sufficiently low, which is not preferable. Further, the base material obtained from the polyester carbonate containing a small amount of the structural unit (III) represented by the general formula (III) is more excellent than the base material obtained from the polycarbonate containing no structural unit (III). Excellent mechanical properties. The preferable mole fraction (z) of the structural unit (III) is 1 mol% or more and 20 mol% or less. It should be noted that a small amount of any other structural unit may be contained within a range in accordance with the object of the present invention. The polymerization rate is usually 10 mol% or less.

The n in the structural unit (I) is preferably 1 or 2 from the viewpoint that a base material having high heat resistance and low absorptivity can be obtained, and 1 from the viewpoint of easy production of the raw material compound. Is more preferable. Specific examples of the structural unit (I) include the following.

[Chemical 5] Further, as A in the structural unit (III), a divalent saturated alicyclic hydrocarbon group having 20 or less carbon atoms is preferable from the viewpoint that a base material having low birefringence and water absorption and high heat resistance can be obtained. Specific examples of the structural unit (III) include the following.

[Chemical 6]

The resin used in the present invention can be produced by a known appropriate method. That is, the corresponding acid, its ester, acid chloride (phosgene for the structural unit (II)), acid anhydride, diol, its ester or alkoxide, etc. is used as a raw material, and the interface method, solution method, melting method, etc. The resin of the present invention can be obtained by the above method. During the reaction, a catalyst can be used if necessary. Examples of the catalyst include (1) various alkoxides, (2) alkali metal, (3) alkali metal hydride, (4) alkali metal hydroxide, and (5) metal halide.
Although the amount of the catalyst used is not particularly limited, it is usually in the range of 0.0001 to 1 mol% with respect to the entire raw material.

The reaction conditions vary depending on the starting materials used and the manufacturing method. For example, when the corresponding ester and diol are manufactured by the melting method, the starting materials and the catalyst are inert such as nitrogen, argon, carbon dioxide and the like. The reaction can be advanced by heating and stirring in a gas atmosphere and distilling phenol when the generated alcohol or phenyl ester is used. The reaction temperature varies depending on the raw material used, the boiling point of the alcohol or phenol produced, and the like, but is usually in the range of 150 to 300 ° C. The reaction time is usually selected from the range of 30 minutes to 10 hours.
In the latter half of the reaction, the system is depressurized as necessary to drive the reaction, but the pressure at this time is usually 0.001 to 100 mmHg.
Is the range. The produced resin can be taken out of the reaction tank in any state such as powder, lump or pellet, and can be used for molding by the same method as that for general transparent resin for molding.

Regarding the molecular weight of the resin in the present invention,
The average molecular weight (converted to polystyrene) by gel permeation chromatography (GPC) is preferably 10,000 or more and 100,000 or less,
It is more preferably from 00 to 80,000.
A resin having a number average molecular weight of 10,000 or less is brittle and sufficient strength cannot be obtained, and it is difficult to synthesize a resin having a number average molecular weight of 100,000 or more.

In the present invention, the antireflection film provided on the light incident surface or the light emitting surface (and both surfaces thereof) of the base material is made of an inorganic dielectric material such as metal oxide, metal sulfide or metal fluoride. preferable. Examples of metal oxides include aluminum oxide, cerium oxide, bismuth oxide,
Chromium oxide, europium oxide, iron oxide, hafnium oxide, indium oxide, lanthanum oxide, molybdenum oxide,
Examples thereof include magnesium oxide, neodymium oxide, lead oxide, praseodymium oxide, samarium oxide, antimony oxide, silicon oxide, scandium oxide, tin oxide, titanium oxide, tantalum oxide, tungsten oxide, yttrium oxide, zirconium oxide, and zinc oxide. Here, the oxidation number is not limited to a constant value. For example, with silicon oxide, the value of x in the composition formula represented by SiOx can take any value from 0 to 2. Moreover, zinc sulfide can be mentioned as an example of a metal sulfide. Examples of metal fluorides include aluminum fluoride, barium fluoride, cerium fluoride, calcium fluoride, lanthanum fluoride, lithium fluoride, magnesium fluoride, cryolite, thiolite, neodymium fluoride, sodium fluoride, fluorine. Examples thereof include lead fluoride, samarium fluoride, and strontium fluoride. As the antireflection film, a film made of an ultraviolet curable resin or the like is also used.

The antireflection film in the present invention is composed of one layer or multiple layers of an inorganic dielectric or the like, and the material constituting the antireflection film and the film thickness of each layer satisfy the required performance based on the refractive index of the constituent material. It is determined as appropriate. The antireflection film made of an inorganic dielectric is formed by vapor deposition, sputtering, CLD.
Method, plating method, or the like. The antireflection film made of resin is formed by a spin coating method, a dip coating method, or the like. In order to improve the adhesion between the antireflection film and the base material, the substrate surface may be subjected to treatments such as cleaning, coating and etching, and the base material may be heated during vapor deposition of the film. Good.

The substrate constituting the optical information recording medium of the present invention is formed by a melt molding method such as a press molding method, an extrusion molding method, an injection molding method, an injection compression molding method, a casting method, or the like.

[0016]

EXAMPLES The present invention will be described below with reference to examples.

(Example 1) 2,3-represented by the following formula
Di (hydroxymethyl) -perhydro-1,4: 5,8
-Dimethanonaphthalene

[Chemical 7] And diphenyl carbonate represented by the following formula

[Chemical 8] It is composed of a colorless transparent resin (number average molecular weight (GPC conversion): 37,000) having a structure as shown in the following formula by a melt polycondensation reaction using tetrabutylammonium tetraphenylborate as a catalyst, using and as starting materials. A long cylindrical chip was obtained.

[Chemical 9] The obtained chips are dried and injection-molded (resin temperature: 250
(° C) by the plastic lens substrate (diameter:
50 mm, thickness: 3 mm, birefringence: 3 nm). An antireflection film composed of three inorganic dielectric layers having an antireflection effect in the visible light region was formed on both front and back surfaces of this substrate by the following method. First layer SiOx (1 <x <2) Refractive index: 1.80
Thickness: 81 nm Second layer TiO ₂ 〃: 2.14
〃: 68nm Third layer SiO ₂ 〃: 1.46
〃: 99 nm The film was formed by the vacuum evaporation method. The first layer was formed by using SiO as an evaporation source and flowing a small amount of oxygen into a vacuum system. The second layer and the third layer respectively use TiO ₂ and SiO ₂ as evaporation sources. The plastic lens thus obtained had an average light transmittance of 99% for wavelengths of 450 nm to 750 nm. After the plastic lens was left in an environment of 80 ° C. and 85% relative humidity for 2000 hours, a visual inspection and a peeling test with an adhesive tape were performed, but no damage was observed in the antireflection film.

(Example 2) In Example 1, instead of 2,3-di (hydroxymethyl) -perhydro-1,4: 5,8-dimethanonaphthalene as a raw material, the following formula was used.

[Chemical 10] A colorless and transparent resin having a structure represented by the following formula (number average molecular weight: 3
3000) was obtained.

[Chemical 11] The obtained chip was dried and injection-molded (resin temperature: 250 ° C.) using a mold having a stamper installed inside to produce a diffraction grating base material (thickness: 1 mm). Here, the stamper used for molding was formed by photolithography. The pitch is 30 μm and the step is 0.25
It is produced by transferring a one-dimensionally arranged pattern of μm onto nickel by an electroforming method. The surface of the mold facing the stamper is a mirror surface, and the distance between the mirror surface and the stamper is 1 mm. The wavelength of the base material of this diffraction grating is 8
The diffraction efficiency for 30 nm was 19.8%, and the birefringence was 3 nm. The following one-layer antireflection film was formed on the grating surface and the back surface of the above-mentioned base material so as to improve the transmittance with respect to a semiconductor laser beam having a wavelength of 830 nm. First layer MgF ₂ Refractive index: 1.38 Thickness: 150n
m The light transmittance of the diffraction grating thus obtained at a wavelength of 830 nm was 98%. 8 the above diffraction grating
After leaving it in an environment of 0 ° C. and a relative humidity of 85% for 2000 hours, a visual inspection and a peeling test with an adhesive tape were performed, but no damage was observed in the antireflection film.

(Example 3) In Example 1, as raw materials, 2,3-di (hydroxymethyl) -perhydro-1,4: 5,8-dimethanonaphthalene used in Example 1 and the following formula

[Chemical 12] A chip composed of a colorless and transparent resin (number average molecular weight: 39000) having a structure represented by the following formula was obtained in the same manner except that a mixture with the compound represented by (molar ratio: 1: 1) was used. Thus, a base material (birefringence: 3 nm) of the plastic lens was prepared, and the same antireflection film as in Example 1 was provided on both front and back surfaces of the base material to manufacture the plastic lens.

[Chemical 13] After the plastic lens was left in an environment of 80 ° C. and 85% relative humidity for 2000 hours, a visual inspection and a peeling test with an adhesive tape were performed, but no damage was observed in the antireflection film.

(Example 4) In Example 2, 2,3-di (hydroxymethyl) -perhydro-1,4: 5,8-dimethanonaphthalene and diphenyl carbonate used in Example 1 were used as raw materials. The following formula (IV)

[Chemical 14] A mixture with a compound represented by (molar ratio: 10: 9: 1)
A chip made of a colorless and transparent resin (average molecular weight: 29000) having a structure represented by the following formula was obtained in the same manner except that was used. From this, the base material of the diffraction grating (birefringence: 4n
m) was prepared, and the same antireflection film as in Example 2 was provided on the grating surface and the back surface of the substrate to prepare a diffraction grating.

[Chemical 15] Place the above diffraction grating in an environment of 80 ° C and 85% relative humidity for 20
After leaving it for 00 hours, a visual inspection and a peeling test with an adhesive tape were performed, but no damage was observed in the antireflection film.

(Example 5) In Example 1, 2.3-di (hydroxymethyl) -perhydro-1,4: 5,8-dimethanonaphthalene used in Example 1 as a raw material and the above formula ( A colorless and transparent resin having a structure represented by the following formula (number average molecular weight of 3200) is similarly used except that a mixture with a compound represented by IV) (molar ratio: 1: 1) is used.
A chip consisting of 0) was obtained. A plastic lens substrate (birefringence: 3 nm) was prepared from this, and the same antireflection film as in Example 1 was provided on both the front and back surfaces of the substrate to prepare a plastic lens.

[Chemical 16] After leaving the above plastic lens in an environment of 80 ° C. and 85% relative humidity for 2000 hours, a visual inspection and a peeling test with an adhesive tape were performed, but no damage was observed in the antireflection film.

Comparative Example 1 PMMA (Kuraray Co., Ltd. made Parapet H as a base material)
-1000) was used to manufacture a plastic lens having an antireflection film in the same manner as in Example 1. Put the above plastic lens in an environment of 80 ° C and 85% relative humidity for 20 minutes.
After leaving it for 00 hours, a visual inspection and a peeling test with an adhesive tape were conducted. As a result, a crack was generated in the antireflection film, and a part was peeled off with the adhesive tape. Comparative Example 2 Using the above PMMA as a base material, a diffraction grating having an antireflection film was produced in the same manner as in Example 2. The above-mentioned diffraction grating is 2,000 in an environment of 85 ° C and 85% relative humidity.
After leaving it for a while, a visual inspection and a peeling test with an adhesive tape were carried out, but cracks occurred in the antireflection film.
The adhesive tape partially peeled off.

[0023]

According to the present invention, an optical component having a small birefringence and a high adhesion of an antireflection film is provided.

Claims (3)

[Claims] 1. The following general formulas (I) to (III): Of the structural units (I) to (III), and the molar fraction (x) of the structural unit (I) is the structural unit (I).
An antireflection film is provided on the surface of a substrate made of a resin that is substantially equal to the total mole fraction (y + z) of the mole fraction (y) of I) and the mole fraction (z) of the structural unit (III). Optical parts characterized by being 2. The following general formulas (I) and (II): The structural unit (I) and the structural unit (II) are represented respectively, and the molar fraction (x) of the structural unit (I) is the structural unit (II).
The optical component is characterized in that an antireflection film is provided on the surface of a base material made of a resin that is substantially equal to the mole fraction (y) of. 3. The following general formulas (I) and (III): The structural unit (I) and the structural unit (III) are respectively represented, and the mole fraction (x) of the structural unit (I) is the structural unit (II
An optical component characterized in that an antireflection film is provided on the surface of a base material made of a resin substantially equal to the molar fraction (z) of I).