JP2008260924A - Resin for optics - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin for optics, which has a refractive index of not less than 1.8 and a pencil hardness of not less than 2H, and is easy to obtain a thin film. <P>SOLUTION: The resin is obtained by polymerizing one or plural compounds having the structure of Y-A-Y' where Y and Y' are groups capable of radical polymerization or cation polymerization, and A is a divalent group having at least one S atom and at least one aromatic ring. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a resin (optical resin) used for optical applications, and an optical component formed using the resin, more specifically, an optical recording medium, an antireflection layer, and the like.

  At present, optical resins having a high refractive index are required in various fields including application to antireflection films in the display field and the like, and cover resins in the optical recording field. The antireflection film is used, for example, to minimize reflection on the display surface and obtain a better display with less reflection, or to minimize reflection on the surface of the glasses and obtain a good field of view. ing.

  There are various types of antireflection films such as a single layer film and a laminated film. At present, an antireflection film having a laminated structure is used for the purpose of minimizing reflection as much as possible regardless of the complexity of the manufacturing process. A multilayer film for antireflection generally requires a multilayer structure of a high refractive index layer and a low refractive index layer, and various materials for constituting each layer have been studied. Moreover, in order to simplify the process for forming a laminated structure, an optical resin that is easy to process is required. However, since there is no optical resin that achieves both a high refractive index and excellent transparency, a laminated structure is mainly formed using inorganic materials. Specifically, an optical resin having a refractive index of 1.8 or more and a transmittance of 50% or more with respect to light having a wavelength of 400 nm to 780 nm at a film thickness to be used is required (for example, Non-patent document 1).

  In addition, as a next-generation optical recording technology, the near-field light (near field light) having a propagation distance shorter than the wavelength of the light is used to narrow the size of the light spot to a fraction of the wavelength, thereby achieving higher density. A technology for recording and reproducing has been attracting attention. This near-field optical recording uses an SIL (solid immersion lens) having a high numerical aperture of about 1.8 to 2.3 as an objective lens, and near-field light leaking from the bottom surface of the SIL irradiated with laser light ( Evanescent waves) are used for recording and reproduction (for example, see Non-Patent Document 2). In order to realize this technique, it is necessary to provide a cover layer having the following characteristics on the optical recording medium.

  First, when the refractive index of the cover layer is low, the size of the light spot when the evanescent wave passes through the cover layer increases, and the recording density decreases. Therefore, in order to improve the recording density, the material of the cover layer is required to have a refractive index higher than the numerical aperture of SIL, that is, a high refractive index higher than 1.8.

  Second, in an optical system for near-field optical recording, the distance between the lens and the optical recording medium needs to be several tens of nm. For this reason, the surface of the optical recording medium, that is, the cover layer surface may be damaged by the collision between the lens and the optical recording medium. In order to prevent damage due to collision with the lens, the cover layer material is required to have a pencil hardness of 2H or more.

  Third, when the cover layer is low in transparency, the evanescent wave is attenuated in the cover layer, and optical recording may not be performed. In order to enable optical recording, the resin forming the cover layer needs to have a transmittance of at least 50% with respect to light having a wavelength of 400 nm to 780 nm at the film thickness to be used.

  Further, in order to effectively use the evanescent wave for optical recording, the cover layer needs to have a film thickness of about several μm. Therefore, the material of the cover layer needs to be able to easily form a thin film having such a film thickness.

Supervised by Masayuki Muranaka, “Technology and Application of Plastic Lenses”, published by CMC Publishing Co., Ltd., June 2003, pp. 278-287 (Applied Chapter, Chapter 6 Eyeglass Lens (Mitsuo Sugiura)) T. Yamasaki et al., "Evaluation of Top Coated Media for Near-Field Optical Disc System of NA 1.84", ISOM / ODS Technical Digest, pp. 284-285 (2006)

  Examples of the optical recording medium material and display material that have been used so far include polycarbonate materials. However, although the polycarbonate material is excellent in transparency and hardness, it has a refractive index of 1.6 or less, and has a disadvantage that the refractive index is too low for use in the production of the near-field optical recording or the antireflection film.

  On the other hand, various materials have been studied as materials having a high refractive index in the plastic lens material field, and materials having a refractive index as high as about 1.8 have been put into practical use. Such materials include, for example, thiourethane materials and thioepoxy materials. However, thiourethane-based materials have the advantages of a high refractive index and a high breaking strength, but they have the disadvantage of high viscosity and difficulty in thinning. In addition, thioepoxy-based materials have the advantages of a high refractive index, a large Abbe number, and excellent heat resistance, but they have the disadvantage of low fracture strength and brittleness. For this reason, there is a problem in terms of hardness when using the thioepoxy material as the cover layer. These problems are the same when an antireflection film using an organic material is realized, and an organic material having a high refractive index and a high hardness has been demanded.

  An object of the present invention is to solve the above-mentioned problems and to realize a material suitable for optical recording and production of an antireflection film. In particular, an object of the present invention is to provide an optical resin having a refractive index of 1.8 or more and a pencil hardness of 2H or more, and an optical component using the same.

The optical resin of the present invention comprises one or more compounds having the structure of formula (I) YAY ′ (I)
(Where Y and Y ′ are

Independently selected from the group consisting of
A is a divalent group having at least one S atom and at least one aromatic ring)
It was obtained by polymerizing.

In the optical resin of the present invention, the ^{A, -R 1 -R 2 -,} - R 1 -S-R 2 -, - R 1 -S (O) -R 2 -, and -R ¹ -S (O It is desirable to select from the group consisting of _2- R ^2- . Here, R ¹ and R ² are each independently

Can be selected from the group consisting of Provided that when A is —R ¹ —R ² —, at least one of R ¹ and R ² is

Should be.

The optical resin of the present invention can be obtained by polymerizing the one or more compounds by light irradiation or heating in the presence of a polymerization initiator. As the polymerization initiator, a radical polymerization initiator or a cationic polymerization initiator can be used. A mixture of the following compounds (A) to (C) may be used as the radical polymerization initiator (wherein R ^{7 to} R ⁹ each represent hydrogen or a methyl group).

Alternatively, the optical resin of the present invention further includes a compound having a functional group selected from the group consisting of an epoxy group, an acrylic group, and an oxetane group in addition to the one or more compounds having the formula (I). It may be formed by polymerization. In addition, the optical resin of the present invention is composed of the following polymer (wherein R ¹⁰ represents hydrogen or a methyl group and R ¹¹ represents a methyl group or an ethyl group), and 5 masses based on the optical resin. % May be further included.

  Furthermore, the optical resin according to the first aspect of the present invention is an organic Ti compound having the following structure:

(Wherein, R ^3, R ⁴ and R ⁵ are, each independently, -OC _n H _2n + 1, is selected from the group consisting of -OCH = CH _2, and -OCOCH = CH _2; R ⁶ is Selected from the group consisting of —OC _n H _{2n + 1} , —OCH═CH ₂ , —OCOCH═CH ₂ , and —TiR ³ R ⁴ R ⁵ ; n is an integer greater than or equal to 1), or in the resin Further, dispersed TiO ₂ nanoparticles may be included.

  As described above, according to the present invention, an optical resin that has a refractive index of 1.8 or more and a hardness of 2H or more and can be easily formed into a thin film can be realized. Furthermore, a thin film having characteristics suitable for a cover layer of an optical recording medium for near-field optical recording can be produced using the obtained optical resin. In addition, the optical resin of the present invention is useful in the production of a thin film having characteristics suitable for an antireflection layer for various optical components.

The optical resin of the present invention has the structure of formula (I) YAY ′ (I)
It can be formed by polymerizing one or more compounds (monomers) having

  In the monomer of formula (I), Y and Y 'are

Independently selected from the group consisting of providing a polymerization site. When the optical resin of the present invention is formed by radical polymerization, the following structures can be used as Y and Y ′.

  Alternatively, when the optical resin of the present invention is formed using cationic polymerization, the following structures can be used as Y and Y ′.

  In the monomer of the formula (I), A is a divalent group having at least one S atom and at least one aromatic ring, and contributes to an improvement in refractive index. Here, at least one S atom may exist as a group connecting two or more aromatic rings, or may exist as an atom constituting at least one aromatic ring.

In the present invention, A represents —R ¹ —R ² —, —R ¹ —S—R ² —, —R ¹ —S (O) —R ² —, or —R ¹ —S (O) ₂ —R. It can have a structure such as ^2- . Here, R ¹ and R ² are each independently a group having an aromatic ring or a heteroaromatic ring which may be optionally substituted with a halogen (particularly bromine). The group that can be used as R ¹ and R ² may have, for example, the following structure.

  In the above structure, the position of the bond valence can be appropriately selected. For example, the phenylene group may be 1,4-phenylene, 1,3-phenylene, or 1,2-phenylene. Similarly, the naphthylene group may be any of 1,4-naphthylene, 1,5-naphthylene, and 2,6-naphthylene. In the above structure, a hydrogen atom at any position other than a bond may be substituted with a halogen atom (particularly a bromine atom).

Here, when A has a structure of —R ¹ —R ² — in which two aromatic rings are directly bonded, at least one of R ¹ and R ² is a heteroaromatic ring containing an S atom. Desirably, for example, it can be a thiophenediyl group having the structure:

  If necessary, the optical resin of the present invention can also be obtained by polymerizing the monomer (one or more) of the formula (I) and an additional compound containing a polymerizable functional group. Can do. As the polymerizable functional group, depending on the polymerization conditions, for example, a group containing a heterocyclic structure of a small ring such as an epoxy group or an oxetane group, or ethylene such as a vinyl group, an allyl group, an acrylic group, or a methacryl group A group containing an ionic double bond can be used. Examples of additional compounds include, for example, glycidol, glycidyl ethers, alkyl vinyl ethers, acrylates, methacrylates, and the like. However, since the refractive index of a general organic material mainly composed of C, H and O is around 1.5, in order to maintain a high refractive index, the content of the additional compound is set to the total mass of the resin. It is desirable to make it 10% by mass or less as a standard.

  The mixture of the monomer (s) of formula (I), the polymerization initiator, and optionally the aforementioned additional compounds is irradiated with light or heated to produce the present mixture. The optical resin of the invention can be formed.

  When the optical resin of the present invention is formed, the above-mentioned mixture is applied to a desired substrate to form an unpolymerized thin film first, and then polymerized by light irradiation or heating to form a thin film of optical resin. It is desirable to form. Application methods that can be used include spin coating, doctor blade, and screen printing.

  As the polymerization initiator, a compound (radical polymerization initiator) that generates free radicals upon irradiation with light or heating from ultraviolet light to visible light can be used. Alternatively, a compound (cationic polymerization initiator) that generates an acid upon irradiation with light or heating from ultraviolet light to visible light (cation polymerization initiator) can be used as the polymerization initiator.

The radical polymerization initiator that can be used in the present invention is:
(A) 2-dimethoxy-1,2-diphenylethane-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1- [4 -(2-hydroxyethoxy) phenyl] -2-hydroxy-2-methylpropan-1-one, 2-hydroxy-1- {4- [4- (2-hydroxy-2-methylpropionyl) benzyl] phenyl}- Α-hydroxyalkylphenones such as 2-methylpropan-1-one;
(B) 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, 2 Α-aminoalkylphenones such as-(dimethylamino) -2-[(4-methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] butan-1-one;
(C) acylphosphine oxides such as 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenyl-phosphine oxide;
(D) titanocenes such as bis (η ₅ -2,4-cyclopentadien-1-yl) -bis [2,6-difluoro-3- (1H-pyrrol-1-yl) -phenyl] titanium;
(E) 1,2-octanedione, 1- [4- (phenylthio)-, 2- (O-benzoyloxime)] (IRGACURE® OXE01), ethanone, 1- [9-ethyl-6- ( Oxime esters such as 2-methylbenzoyl) -9H-carbazol-3-yl]-, 1- (O-acetyloxime) (IRGACURE® OXE02);
(F) Peroxyketals (1,1-bis (t-butylperoxy) cyclohexane, 1.1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, etc.), dialkyl peroxides (dicumyl peroxide) , T-butylcumyl peroxide, di-t-butyl peroxide), peroxydicarbonates (t-butylperoxyisopropyl carbonate), diacyl peroxides, peroxyesters, ketone peroxides, hydroperoxides, etc. Including things. One of the foregoing may be used alone as a radical polymerization initiator, or a mixture of two or more may be used.

Alternatively, a mixture of the following compound (A) ([2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propanone] oligomer), compound (B) and compound (C) may be a radical. You may use as a polymerization initiator (In formula, R < ⁷ > -R < ⁹ > shows hydrogen or a methyl group, respectively). This mixture is effective in shortening the photopolymerization time and improving the flatness of the film (surface roughness of 5 nm or less).

  Cationic polymerization initiators that can be used in the present invention and generate an acid upon irradiation with light or heating are, for example, aromatic diazonium salts (p-methoxybenzenediazonium hexafluorophosphate, etc.), aromatic sulfonium salts (triphenylsulfonium hexaxane). Fluorophosphate etc.), aromatic iodonium salts (diphenyliodonium hexafluorophosphate etc.), aromatic iodosyl salts, aromatic sulfoxonium salts, metallocene compounds and the like.

  When the polymerization is carried out by light irradiation, light having various wavelengths ranging from ultraviolet light to visible light may be used depending on the type of polymerization initiator used. Light sources that can be used include, but are not limited to, ultra-high pressure mercury lamps, halogen lamps, xenon lamps, metal halide lamps, and LEDs (ultraviolet or visible).

  When the polymerization is carried out by heating, the heating temperature can vary depending on the type of polymerization initiator used. Heating can be carried out using any means known in the art (heating furnace, infrared lamp, etc.).

Optionally, the optical resin of the present invention comprises a polymer represented by formula (D) (wherein R ¹⁰ represents hydrogen or a methyl group, and R ¹¹ represents a methyl group or an ethyl group), It may further be contained in an amount of 5% by mass or less based on the optical resin. By including such a polymer, the flatness of the film formed using the optical resin of the present invention can be improved. For example, a film having a surface roughness of 5 nm or less can be formed.

  The optical resin of the present invention may be a resin composition containing an organic Ti compound having the following structure.

Wherein R ³ , R ⁴ and R ⁵ are each independently selected from the group consisting of —OC _n H _{2n + 1} , —OCH═CH ₂ , and —OCOCH═CH ₂ . R ⁶ is selected from the group consisting of —OC _n H _{2n + 1} , —OCH═CH ₂ , —OCOCH═CH ₂ , and —TiR ³ R ⁴ R ⁵ . N is an integer of 1 or more. When using this organic Ti compound, it is desirable to first mix the monomer of formula (I) or a mixture thereof and the organic Ti compound, and then perform polymerization to obtain a resin. Organic Ti compounds that can be used include, for example, Ti (OC ₄ H ₉ ) ₄ , (C ₄ H ₉ O) ₃ TiOTi (OC ₄ H ₉ ) _{3 and the} like. Such an organic Ti compound is effective in further increasing the refractive index of the obtained resin.

The mixing ratio of the organic Ti compound to the optical resin of the present invention is determined in consideration of the compatibility between the organic Ti compound used and the resin. In order to mix an organic Ti compound with a given resin in an arbitrary ratio, the organic Ti compound has a structure similar to the reactive group (Y and Y ′) of the monomer constituting the resin. It is desirable to include a group. For example, when the reactive group of the monomer has a structure containing an acrylic group, it is desirable that one of R ^{3 to} R ⁶ constituting the organic Ti compound is —OCOCH═CH ₂ . When Ti (OC ₄ H ₉ ) ₄ and (C ₄ H ₉ O) ₃ TiOTi (OC ₄ H ₉ ) ₃ are used, Y and Y ′ in formula (I) are substituted with —SCH═CH ₂ group. It is necessary to use a resin formed from a monomer having the same.

Alternatively, the optical resin of the present invention may be a resin composition further containing TiO ₂ nanoparticles dispersed therein. The “TiO ₂ nanoparticle” in the present invention means TiO ₂ fine particles having an average particle diameter of 5 to 30 nm. The TiO ₂ nanoparticles are desirably mixed with the monomer of formula (I) before polymerization. TiO ₂ nanoparticles are effective in that the refractive index of the resulting resin is further increased.

1, bis (4-vinyl-thio-phenyl) sulfide respect (below, Compound (M-1)) and by mixing the TiO ₂ nanoparticles, the composition of the resin obtained by polymerizing a mixture, TiO ₂ nano The relationship between the mixing ratio (% by mass) of particles and the refractive index is shown.

FIG. 1 shows that a resin having a refractive index of 2.0 or more can be obtained by setting the mixing ratio of TiO ₂ nanoparticles to 21 to 50% by mass (based on the total mass of the mixture). When the mixing ratio of TiO ₂ nanoparticles is 50% by mass or more, it is difficult to uniformly disperse the nanoparticles in the mixture and it is also difficult to obtain a resin film having a transmittance of 90% or more. Met.

  One form of the optical component of the second aspect of the present invention is an optical recording medium 100 as shown in FIG. The optical recording medium 100 includes at least a substrate 10, an optical recording layer 20 formed on the substrate 10, and a cover layer 30 formed on the optical recording layer 20, and the cover layer 30 is for optical use of the present invention. It is formed of resin.

  The substrate 10 preferably has reflectivity in order to reproduce recorded information. As shown in FIG. 2, the substrate 10 may have a two-layer configuration including a support 11 and a reflective layer 12 formed on the support 11. The support 11 in the two-layer configuration may be formed using any transparent material known in the art such as polycarbonate resin and glass. The reflection layer 12 is a layer for sufficiently reflecting light used for reproducing a recorded signal. The reflective layer 12 can be formed using any method known in the art, such as aluminum deposition.

  The optical recording layer 20 is formed using a material whose state changes with respect to signal reproduction light by the action of light for recording a signal. The change in state may be either irreversible or reversible. The optical recording layer 20 can be formed using any material known in the art.

  The cover layer 30 is a layer formed of the optical resin of the present invention, and has a refractive index of 1.8 or more, a pencil hardness of 2H or more, and a transparency of 50% or more with respect to signal recording light and signal reproduction light. Have

  Another form of the optical component of the second aspect of the present invention is an antireflection film 200 as shown in FIG. The antireflection film 200 includes at least a glass substrate 50, a high refractive index layer 60 formed on the glass substrate 50, and a low refractive index layer 70 formed on the high refractive index layer 60. The rate layer 60 is formed of the optical resin of the present invention.

  The high refractive index layer 60 is a layer formed of the optical resin of the present invention, and has a refractive index of 1.8 or more and transparency of 50% or more with respect to light that is an object of antireflection.

  The low refractive index layer 70 is a layer having a refractive index smaller than that of the high refractive index layer 60. The low refractive index layer 70 preferably has a refractive index of 80% or less, more preferably 60 to 70% of the refractive index of the high refractive index 60. More specifically, the low refractive index layer 70 has a refractive index of 1.3 to 1.4. The low refractive index layer 70 can be formed using any material known in the art such as a polyperfluoroolefin resin.

  In FIG. 3, the antireflection film 200 having one high refractive index layer 60 and one low refractive index layer 70 is illustrated. However, the antireflection film of the present invention may have a laminated structure of a plurality of high refractive index layers and a plurality of low refractive index layers. The refractive index, the film thickness, and the stacking order of each constituent layer can be appropriately determined in consideration of the wavelength of light that is the object of antireflection.

Example 1
98% by mass of bis (4-vinylthiophenyl) sulfide) (compound (M-1)) and 2-hydroxy-1- {4- [2- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl } 2-Methyl-propan-1-one (compound (I-1) below) 2% by mass was mixed.

This mixture was applied onto a silicon substrate using a spin coating method. The conditions for the spin coating method were 1000 revolutions and 60 seconds. Thereafter, using an ultraviolet irradiation device, ultraviolet rays were irradiated for 600 seconds at an intensity of 100 mW / cm ² , and the applied mixture was photocured. Subsequently, the film was completely cured by heating to 80 ° C. for 1 hour in a thermostatic bath.

  The resulting film had a film thickness of 6 μm. The refractive index of the film measured by the prism coupling method using a Metricon PC2010 type prism coupler was 1.82 with respect to light having a wavelength of 405 nm. Further, the film hardness measured with a pencil hardness meter in accordance with JIS 5400 was 3H. In addition, the film of this example had a surface roughness of 18 nm. Further, the separately formed film having a thickness of 3 μm had 95% transparency (transmittance of light having a wavelength of 405 nm).

(Example 2)
98% by mass of bis (4-vinylthiophenyl sulfide) (compound (M-1)) and 50% concentration of (4-methylphenyl) [4- (2-methylpropyl) phenyl] iodonium hexafluorophosphate (described below) The procedure of Example 1 was repeated except that a mixture of the compound (I-2)) with 2% by mass of a propylene carbonate solution was used.

  The resulting film had a film thickness of 6 μm. The refractive index of the obtained film was 1.825 for light having a wavelength of 405 nm. The film hardness was 2H. Further, the separately formed film having a thickness of 3 μm had a transparency of 95%.

(Example 3)
Bis (4-vinylthiophenyl) sulfide) (compound (M-1)) 68% by mass, bis (4-methacryloylthiophenyl) sulfide) (hereinafter, compound (M-2)) 30% by mass, 2- Hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propan-1-one (compound (I-1)) 2% by mass The procedure of Example 1 was repeated except that was used.

  The resulting film had a film thickness of 6 μm. The refractive index of the obtained film was 1.825 for light having a wavelength of 405 nm. The film hardness was 2H. Further, the separately formed film having a thickness of 3 μm had a transparency of 95%.

Example 4
35% by mass of bis (4-vinylthiophenyl) sulfide) (compound (M-1)), 63% by mass of Ti (OC ₄ H ₉ ) ₄ (compound (T-1)), 2% by mass of A mixture with 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propan-1-one (compound (I-1)) The procedure of Example 1 was repeated except that it was used and the heating temperature in the thermostat after light irradiation was changed to 100 ° C.

  The resulting film had a thickness of 3 μm. The obtained film had a refractive index of 1.95 with respect to light having a wavelength of 405 nm and 90% transparency. The film hardness was 4H.

(Example 5)
45% by mass of bis (4-vinylthiophenyl) sulfide) (compound (M-1)), 53% by mass of Ti (OC ₄ H ₉ ) ₄ (compound (T-1)), 2% by mass of A mixture with 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propan-1-one (compound (I-1)) The procedure of Example 4 was repeated except that it was used.

  The resulting film had a thickness of 3 μm. The obtained film had a refractive index of 1.92 with respect to light having a wavelength of 405 nm and 90% transparency. The film hardness was 4H.

(Example 6)
Bis (4-vinylthiophenyl) sulfide) (compound (M-1)) 58% by mass, bis (4-methacryloylthiophenyl) sulfide) (hereinafter, compound (M-2)) 40% by mass, 2- Hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propan-1-one (compound (I-1)) 2% by mass The procedure of Example 4 was repeated except that was used.

  The resulting film had a thickness of 3 μm. The obtained film had a refractive index of 1.828 with respect to light having a wavelength of 405 nm and 90% transparency. The film hardness was 2H.

(Example 7)
50% by mass of bis (4-vinylthiophenyl) sulfide) (compound (M-1)), 48% by mass of bis (4-methacryloylthiophenyl) sulfide) (compound (M-2) below), 2- Hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propan-1-one (compound (I-1)) 2% by mass The procedure of Example 4 was repeated except that was used.

  The resulting film had a thickness of 3 μm. The obtained film had a refractive index of 1.831 with respect to light having a wavelength of 405 nm and had a transparency of 95%. The film hardness was 2H.

(Example 8)
8% by mass of bis (4-methacryloylthiophenyl) sulfide) (compound (M-2) below) and 90% by mass of (C ₄ H ₉ O) ₃ TiOTi (OC ₄ H ₉ ) ₃ (compound (T -2)) and 2% by weight of 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propan-1-one (compound) The procedure of Example 4 was repeated except that a mixture with (I-1)) was used.

  The resulting film had a thickness of 2 μm. The refractive index of the obtained film was 2.35 with respect to light having a wavelength of 405 nm. The film hardness was 4H. Further, the separately formed film having a thickness of 3 μm had 90% transparency.

Example 9
50% by mass of bis (4-vinylthiophenyl) sulfide) (compound (M-1)), 8% by mass of bis (4-methacryloylthiophenyl) sulfide) (hereinafter, compound (M-2)), 40% by mass of (C ₄ H ₉ O) ₃ TiOTi (OC ₄ H ₉ ) ₃ (compound (T-2)) and 2% by mass of 2-hydroxy-1- {4- [4- (2-hydroxy The procedure of Example 4 was repeated except that a mixture with 2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propan-1-one (compound (I-1)) was used.

  The resulting film had a thickness of 3 μm. The obtained film had a refractive index of 1.98 with respect to light having a wavelength of 405 nm, and had 95% transparency. The film hardness was 3H.

(Example 10)
40% by mass of bis (4-vinylthiophenyl) sulfide) (compound (M-1)), 8% by mass of bis (4-methacryloylthiophenyl) sulfide) (hereinafter, compound (M-2)), 50% by mass of (C ₄ H ₉ O) ₃ TiOTi (OC ₄ H ₉ ) ₃ (compound (T-2)) and 2% by mass of 2-hydroxy-1- {4- [4- (2-hydroxy The procedure of Example 4 was repeated except that a mixture with 2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propan-1-one (compound (I-1)) was used.

  The resulting film had a thickness of 3 μm. The obtained film had a refractive index of 2.0 with respect to light having a wavelength of 405 nm and had 90% transparency. The film hardness was 3H.

(Example 11)
30% by mass of bis (4-vinylthiophenyl) sulfide) (compound (M-1)), 8% by mass of bis (4-methacryloylthiophenyl) sulfide) (hereinafter, compound (M-2)), 60% by mass of (C ₄ H ₉ O) ₃ TiOTi (OC ₄ H ₉ ) ₃ (compound (T-2)) and 2% by mass of 2-hydroxy-1- {4- [4- (2-hydroxy The procedure of Example 4 was repeated except that a mixture with 2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propan-1-one (compound (I-1)) was used.

  The resulting film had a thickness of 3 μm. The obtained film had a refractive index of 2.1 with respect to light having a wavelength of 405 nm and had 90% transparency. The film hardness was 3H.

(Example 12)
20% by mass of bis (4-vinylthiophenyl) sulfide) (compound (M-1)), 8% by mass of bis (4-methacryloylthiophenyl) sulfide) (hereinafter, compound (M-2)), 70% by mass of (C ₄ H ₉ O) ₃ TiOTi (OC ₄ H ₉ ) ₃ (compound (T-2)) and 2% by mass of 2-hydroxy-1- {4- [4- (2-hydroxy The procedure of Example 4 was repeated except that a mixture with 2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propan-1-one (compound (I-1)) was used.

  The resulting film had a thickness of 3 μm. The obtained film had a refractive index of 2.2 with respect to light having a wavelength of 405 nm and had 90% transparency. The film hardness was 3H.

(Example 13)
(I) 94% by mass of bis (4-vinylthiophenyl) sulfide) (compound (M-1)) and (ii) [2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] ] Propanone] oligomer (below, compound (A)), 2,4,6-trimethylbenzoylbenzene (below, compound (B-1)) and (2,4,6-trimethylbenzoyl) diphenylphosphine oxide (below, compound) (C)) 3% by mass of the mixture and (iii) 3% by mass of mercaptopropyltrimethoxysilane were mixed. The mixing ratio of the compounds (A), (B-1), and (C) was 2: 1: 1 by mass ratio.

This mixture was applied onto a silicon substrate using a spin coating method. The conditions for the spin coating method were 1000 revolutions and 60 seconds. Thereafter, using an ultraviolet irradiation device, ultraviolet rays were irradiated for 600 seconds at an intensity of 100 mW / cm ² , and the applied mixture was photocured.

  The resulting film had a film thickness of 6 μm. The refractive index of the film measured by the prism coupling method using a Metricon PC2010 type prism coupler was 1.82 with respect to light having a wavelength of 405 nm. Further, the film hardness measured with a pencil hardness meter in accordance with JIS 5400 was 3H. Further, the separately formed film having a thickness of 3 μm had 95% transparency (transmittance of light having a wavelength of 405 nm). Furthermore, the flatness of the film was evaluated by the surface roughness. The film of this example had a surface roughness of 3 nm, and was not more than 1/4 of the surface roughness of 18 nm of the film of Example 1. The film of this example could be photocured in 1/10 time compared to the film of Example 1.

(Example 14)
(I) 94% by mass of bis (4-vinylthiophenyl) sulfide) (compound (M-1)) and (ii) [2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] ] Propanone] oligomer (below, compound (A)), 2,4,6-trimethylbenzoylbenzene (below, compound (B-1)) and (2,4,6-trimethylbenzoyl) diphenylphosphine oxide (below, compound) 3% by mass of the mixture of (C)) and 3% by mass of (iii) polyethyl methacrylate (average molecular weight 5,000 to 10,000) were mixed. The mixing ratio of the compounds (A), (B-1), and (C) was 2: 1: 1 by mass ratio.

This mixture was applied onto a silicon substrate using a spin coating method. The conditions for the spin coating method were 1000 revolutions and 60 seconds. Thereafter, using an ultraviolet irradiation device, ultraviolet rays were irradiated for 600 seconds at an intensity of 100 mW / cm ² , and the applied mixture was photocured.

  The resulting film had a film thickness of 6 μm. The refractive index of the film measured by the prism coupling method using a Metricon PC2010 type prism coupler was 1.82 with respect to light having a wavelength of 405 nm. Further, the film hardness measured with a pencil hardness meter in accordance with JIS 5400 was 3H. Further, the separately formed film having a thickness of 3 μm had 95% transparency (transmittance of light having a wavelength of 405 nm). Furthermore, the flatness of the film was evaluated by the surface roughness. The film of this example had a surface roughness of 3 nm, and was not more than 1/4 of the surface roughness of 18 nm of the film of Example 1.

  Separately, the addition amount of the acrylic polymer (polyethyl methacrylate) represented by the formula (D) was examined. As a result, it was observed that when 3% by mass or more of polyethyl methacrylate was added, the uniformity of the resin was lost and a film having a transparency of 80% or less was formed. From this result, it was found that the addition amount of the acrylic polymer represented by the formula (D) is desirably 3% by mass or less.

(Example 15)
An optical recording layer 20 made of a triazole dye having a thickness of 150 nm was formed on a substrate 10 made of a disk-shaped polycarbonate support 11 having a diameter of 12 cm and a reflective layer 12 formed by vapor deposition of aluminum. Further, a cover layer 30 having a thickness of 3 μm was formed on the optical recording layer 20 to obtain an optical recording medium 100 having a structure shown in FIG. The cover layer 30 comprises 98% by mass of bis (4-vinylthiophenyl) sulfide) (compound (M-1)) and 2% by mass of 2-hydroxy-1- {4- [4- (2-hydroxy- Formed according to the procedure described in Example 1 using a mixture with 2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propan-1-one (compound (I-1)).

  When the obtained optical recording medium was recorded with light having a wavelength of 405 nm, it was possible to record data of 100 GB or more.

(Example 16)
A high refractive index layer 60 having a film thickness of 0.2 μm was formed on the glass substrate 50 using the optical resin of the present invention. The high refractive index layer 60 comprises 98% by mass of bis (4-vinylthiophenyl) sulfide) (compound (M-1)) and 2% by mass of 2-hydroxy-1- {4- [4- (2- Using a mixture with hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propan-1-one (compound (I-1)), the spin coating conditions were changed to 7000 rpm and 60 seconds Except as described, it was formed according to the procedure described in Example 1. A polyperfluoroolefin resin was applied on the high refractive index layer 60 to form a low refractive index layer 70 having a thickness of 0.15 μm, and an antireflection film 200 having the structure shown in FIG. 3 was obtained. The refractive index of the low refractive index layer 70 was 1.34.

  With respect to light in the visible light region centered on a wavelength of 540 nm, the reflection loss of the glass substrate 50 used alone and the obtained antireflection film 200 was measured. The reflection loss of the antireflection film 200 obtained in this example is about 1%, which is remarkably improved compared to the reflection loss (10%) in the case of the glass substrate 50 alone.

It is a diagram showing a relationship between the mixing ratio of TiO ₂ nanoparticles in the present invention and (mass%) and the refractive index. It is a figure which shows the optical recording medium which is one form of the optical component of the 2nd aspect of this invention. It is a figure which shows the antireflection film which is another form of the optical component of the 2nd aspect of this invention.

Claims (9)

One or more compounds having the structure of formula (I) YA-Y '(I)
(Where Y and Y ′ are

Independently selected from the group consisting of
A is a divalent group having at least one S atom and at least one aromatic ring)
An optical resin obtained by polymerizing A consists of —R ¹ —R ² —, —R ¹ —S—R ² —, —R ¹ —S (O) —R ² —, and —R ¹ —S (O) ₂ —R ² —. Selected from the group,
R ¹ and R ² are each independently

Selected from the group consisting of
When A is —R ¹ —R ² —, at least one of R ¹ and R ² is

The optical resin according to claim 1, wherein:   The optical resin according to claim 1, wherein the resin is obtained by polymerizing the one or more compounds by light irradiation or heating in the presence of a polymerization initiator.   The optical resin according to claim 1, wherein a compound having a functional group selected from the group consisting of an epoxy group, an acrylic group, and an oxetane group is further polymerized.   The optical resin according to claim 3, wherein the polymerization initiator is a radical polymerization initiator or a cationic polymerization initiator. The polymerization initiator is a mixture of compounds (A) to (C) having the following structure:

The optical resin according to claim 5, wherein R ^{7 to} R ⁹ each represent hydrogen or a methyl group. The following structure

(Wherein R ¹⁰ represents hydrogen or a methyl group, R ¹¹ represents a methyl group or an ethyl group), and the content of the polymer is 3 mass based on the optical resin. The optical resin according to claim 1, wherein the optical resin is not more than%. Organic Ti compound having the following structure

(Wherein, R ^3, R ⁴ and R ⁵ are, each independently, -OC _n H _2n + 1, is selected from the group consisting of -OCH = CH _2, and -OCOCH = CH _2; R ⁶ is Selected from the group consisting of —OC _n H _{2n + 1} , —OCH═CH ₂ , —OCOCH═CH ₂ , and —TiR ³ R ⁴ R ⁵ ; n is an integer greater than or equal to 1)
The optical resin according to claim 1, further comprising: The optical resin according to claim 1, further comprising TiO ₂ nanoparticles dispersed in the resin.

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