JP4704175B2 - Optical lens composition, optical lens and optical component - Google Patents

Description

  The present invention relates to an optical lens composition, an optical lens, and an optical component, and more particularly, an optical lens composition that has a high light transmittance for visible light and can improve the refractive index and toughness, and The present invention relates to an optical lens that is excellent in light transmittance, refractive index, and toughness by constituting a lens body from a composition for optical lenses, and an optical component that includes this optical lens.

Conventionally, cameras, film-integrated cameras such as lens-equipped cameras, various cameras such as video cameras, optical pickups such as CDs, CD-ROMs, MOs, CD-Rs, CD-Videos and DVDs, OAs such as copiers and printers Optical elements used in various devices such as devices are required to have basic optical characteristics such as high light transmittance and high refractive index, and furthermore, high thermal stability, high hardness, low water absorption, and high weather resistance. Various properties such as properties and solvent resistance are required.
One of these optical elements is an optical lens molded using a resin such as polymethyl methacrylate (PMMA), polycyclohexyl methacrylate, or polycarbonate (PC) (see, for example, Patent Document 1). In particular, as an optical lens having excellent heat resistance and chemical resistance, a plastic lens using polyethylene glycol bisallyl carbonate has been proposed.
JP 2001-89660 A

By the way, in the conventional resin optical lens, polymethyl methacrylate (PMMA), polycyclohexyl methacrylate, polycarbonate (PC), etc. are used. Therefore, the thermal stability is low, the water absorption is high, and the environment, particularly high temperature and high temperature. It has drawbacks such as optical characteristics fluctuating in a humid environment, and there is a problem that it is difficult to cope with high heat stability, low water absorption, high weather resistance, etc. that have been conventionally required. .
In addition, plastic lenses that are considered to have excellent heat resistance and chemical resistance have a low refractive index and are not so high in heat resistance, and it is difficult to meet demands for high thermal stability, high refractive index, etc. It was a thing.

  The present invention has been made to solve the above-described problems, and provides an optical lens composition, an optical lens, and an optical component that have high transparency and can improve the refractive index and toughness. With the goal.

The present inventors show that when zirconia particles as an inorganic filler, especially tetragonal zirconia is added as the second phase of the composite material, the composite material exhibits high toughness due to volume expansion called martensitic transformation. Focusing on the above, even if the conventional zirconia particles have a coarse primary particle size of several μm to a fine one of several nm, the aggregation is intense, and even when kneaded in a resin, the diameter is several μm. As a result of intensive studies in order to overcome the disadvantage that the transparency of the sealing material is lost due to the presence of coarse particles, tetragonal zirconia particles having a dispersed particle diameter of 1 nm or more and 20 nm or less are obtained as zirconia particles. If the lens body is composed of a composition for optical lenses containing tetragonal zirconia particles and a transparent resin , high light transmittance, high refractive index, high thermal stability, high hardness and weather resistance The present invention has been found to satisfy the above.

That is, the optical lens composition of the present invention is characterized by containing tetragonal zirconia particles having a dispersed particle diameter of 1 nm or more and 20 nm or less and a transparent resin .
The tetragonal zirconia particles are preferably dispersed in a resin.
The content of the tetragonal zirconia particles is preferably 1% by weight or more and 80% by weight or less.

  The optical lens of the present invention is characterized in that at least the light transmission region is composed of the optical lens composition of the present invention.

  An optical component according to the present invention includes the optical lens according to the present invention.

According to the composition for an optical lens of the present invention, since the dispersion particle size contains tetragonal zirconia particles having a particle diameter of 1 nm or more and 20 nm or less and a transparent resin , the transparency can be maintained, and the refractive index and toughness can be maintained. Can be improved.

  According to the optical lens of the present invention, at least the light transmission region is composed of the optical lens composition of the present invention, so that the transparency of the light transmission region can be maintained, and the refractive index, thermal stability, hardness And weather resistance can be improved. Therefore, reliability can be improved over a long period of time.

  According to the optical component of the present invention, since the optical lens of the present invention is provided, the performance as the component can be improved, and the reliability of the optical component can be improved over a long period of time.

The best mode for carrying out the optical lens composition, the optical lens, and the optical component of the present invention will be described.
This embodiment is specifically described for better understanding of the gist of the invention, and does not limit the present invention unless otherwise specified.

“First Embodiment”
FIG. 1 is a sectional view showing an optical lens according to a first embodiment of the present invention.
In the figure, 1 is a transparent substrate made of a flat transparent composite, 2 is a substantially hemispherical minute convex lens portion formed on the surface (one surface) of the transparent substrate 1, and the transparent substrate 1 and The entire convex lens portion 2 is a light transmission region.

This transparent composite is a transparent composite in which tetragonal zirconia particles having a dispersed particle diameter of 1 nm or more and 20 nm or less are dispersed in a transparent resin.
Here, the reason why the zirconia particles are limited to tetragonal zirconia particles is that, from the standpoint of fine particle synthesis, if the particle size of the fine particles is as small as 20 nm or less, the tetragonal crystals are more than the monoclinic crystals conventionally known. In addition to being stable and having high hardness, the mechanical properties of the transparent composite can be improved, and in the transparent composite in which zirconia particles are dispersed in the resin, tetragonal zirconia is added to the transparent composite. This is because when added as two phases, compared to the case where monoclinic zirconia particles are added, high toughness is exhibited by volume expansion called martensitic transformation.

Further, the reason why the dispersed particle diameter of tetragonal zirconia particles is limited to 1 nm or more and 20 nm or less is that when the dispersed particle diameter is less than 1 nm, crystallinity becomes poor and it is difficult to express particle characteristics such as refractive index. On the other hand, if the dispersed particle diameter exceeds 20 nm, the transparency is lowered in the case of a dispersion or a transparent composite.
Thus, since the tetragonal zirconia particles are nano-sized particles, even in a transparent composite compounded with a resin, light scattering is small and the transparency of the composite can be maintained.

  The resin may be a resin having transparency with respect to light in a predetermined wavelength band such as visible light, near infrared light, or near ultraviolet light. Thermoplastic, thermosetting, light by visible light, ultraviolet light, infrared light, or the like. Curing resins such as (electromagnetic wave) curability and electron beam curability by electron beam irradiation are preferably used.

  Examples of this resin include acrylates such as polymethyl methacrylate (PMMA) and polycyclohexyl methacrylate, polycarbonate (PC), polystyrene (PS), polyether, polyester, polyarylate, polyacrylate, polyamide, phenol-formaldehyde ( Phenol resin), diethylene glycol bisallyl carbonate, acrylonitrile / styrene copolymer (AS resin), methyl methacrylate / styrene copolymer (MS resin), poly-4-methylpentene, norbornene polymer, polyurethane, epoxy, silicone, etc. Is mentioned.

Here, an acrylate resin, a silicone resin, and an epoxy resin among said resin are demonstrated in detail.
"Acrylate resin"
As the acrylate resin, a monofunctional acrylate and / or a polyfunctional acrylate is used, and one or more of these are used.
Specific examples of the monofunctional acrylate and the polyfunctional acrylate will be described below.
(A) As an aliphatic monofunctional (meth) acrylate,
Alkyl (meth) acrylates such as butyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, etc. Alkoxyalkylene glycol (meth) acrylates such as methoxypropylene glycol (meth) acrylate and ethoxydiethylene glycol (meth) acrylate (meth) Examples include N-substituted acrylamides such as acrylamide and N-butoxymethyl (meth) acrylamide.

(B) As aliphatic polyfunctional (meth) acrylate,
1,6-hexanediol di (meth) acrylate, 1.4-butanediol di (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene Alkylene glycol di (meth) such as glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polybutanediol di (meth) acrylate, etc. Acrylate Pentaerythritol triacrylate, trimethylolpropane tri (meth) acrylate, ethylene oxide, propylene oxide modified trimethylolpropane triacrylate Examples include tetra (meth) acrylates such as tri (meth) acrylates such as dibasic ester, tetra (meth) acrylates such as di-trimethylolpropane tetraacrylate, and penta (meth) acrylates such as dipentaerythritol (monohydroxy) pentaacrylate.

(C) Among the alicyclic (meth) acrylates, the monofunctional type includes cyclohexyl (meth) acrylate, and the polyfunctional type includes dicyclopentadienyl di (meth) acrylate.
(D) Among aromatic (meth) acrylates, monofunctional types include phenyl (meth) acrylate, benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, and the like. Examples of the mold include diacrylates such as bisphenol A di (meth) acrylate, bisphenol F di (meth) acrylate, and the like.

(E) Examples of the polyurethane (meth) acrylate include polyurethane ether (meth) acrylate and polyester (meth) acrylate.
(F) Examples of the epoxy (meth) acrylate include bisphenol A type epoxy acrylate and novolac type epoxy acrylate.

  As radical polymerization initiators, lauroyl peroxide, benzoyl peroxide, di-t-butyl peroxide, t-butylperoxy-2-ethylhexanoate, t-butylperoxyisobutyrate, t-butylperoxy Examples thereof include peroxide polymerization initiators such as pivalate, t-butyl peroxybenzoate, and t-butyl peroxyacetate, and azo polymerization initiators such as 2,2′-azobisisobutyronitrile.

"Silicone resin"
The silicone resin is preferably composed of at least the following components (a) to (c).
(A) Organopolysiloxane in which at least two functional groups bonded to silicon atoms in one molecule are alkenyl groups (b) Whether at least two functional groups bonded to silicon atoms in one molecule are hydrogen atoms Or a linear organopolysiloxane (c) hydrosilylation catalyst in which both ends of the molecular chain are blocked with hydrogen atoms

(A) As an alkenyl group in a component, a vinyl group, an allyl group, a pentenyl group, a hexenyl group etc. are mentioned, Especially a vinyl group is preferable.
Examples of functional groups bonded to silicon atoms other than alkenyl groups include alkyl groups such as methyl, ethyl, propyl, and butyl groups, aryl groups such as phenyl and tolyl groups, benzyl groups, and phenethyl groups. Examples thereof include an aralkyl group, and a methyl group is particularly preferable.

(B) Functional groups bonded to silicon atoms other than hydrogen atoms in the component include alkyl groups such as methyl group, ethyl group, propyl group and butyl group, aryl groups such as phenyl group and tolyl group, benzyl group and phenethyl. And an aralkyl group such as a group, and a methyl group is particularly preferable.
In addition, the content of the component (b) is preferably an amount such that the hydrogen atoms are in the range of 0.1 to 10 mol with respect to 1 mol of the total alkenyl groups contained in the component (a). The amount is preferably in the range of 0.1 to 5 mol, and more preferably in the range of 0.5 to 2 mol.

The catalyst for hydrosilylation reaction of component (c) is a catalyst for promoting a hydrosilylation reaction between an alkenyl group in component (a) and a hydrogen atom bonded to a silicon atom in component (b). Examples of such a catalyst include a platinum-based catalyst, a rhodium-based catalyst, a palladium-based catalyst, and the like, and a platinum-based catalyst is particularly preferable.
Examples of the platinum-based catalyst include fine platinum powder, chloroplatinic acid, platinum-olefin complex, platinum carbonyl complex and the like, and chloroplatinic acid is particularly preferable.

  Further, the content of the component (c) is an amount capable of promoting the curing of the composition, that is, hydrosilyl of an alkenyl group in the component (a) and a hydrogen atom bonded to a silicon atom in the component (b). There is no particular limitation as long as it is an amount capable of promoting the chemical reaction, and specifically, the metal atom in the present component is 0.01 to 500 ppm by weight with respect to the present composition. It is preferably within the range, more preferably within the range of 0.01 to 50 ppm.

The reason why the content of the metal atom in this component is limited as described above is that if the content is less than 0.01 ppm, the composition may not be sufficiently cured, while the content is This is because if it exceeds 500 ppm, the obtained cured product may have problems such as coloring.
About this silicone resin, unless the objective of this invention is impaired, you may contain a heat-resistant agent, dye, a pigment, a flame retardance imparting agent, etc. as other arbitrary components.

"Epoxy resin"
As an epoxy resin,
(A) Bifunctional glycidyl ether type epoxy resin such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, hydrogenated bisphenol A type epoxy resin, biphenyl type epoxy resin,
(B) Polyfunctional glycidyl ether type such as phenol novolac type epoxy resin, orthocresol novolac type epoxy resin, alkyl-modified triphenolmethane type epoxy resin, tris-hydroxyphenylmethane type epoxy resin, tetraphenylolethane type epoxy resin Epoxy resin,
(C) Tetraglycidyldiaminidiphenylmethane type epoxy resin, triglycidyl isocyanurate type epoxy resin, aminophenol type epoxy resin, aniline type epoxy resin, toluidine type epoxy resin, and other glycidylamine type epoxy resins.

As the curing agent for epoxy resin, any of polyaddition type, catalyst type and condensation type can be used. For example, diaminodiphenylmethane, diaminodiphenylsulfone, polyamide, dicyandiamide, diethylenetriamine, triethylenetetramine, hexahydro anhydride Examples thereof include phthalic acid and methyltetrahydrophthalic anhydride.
To these resins, an antioxidant, a release agent, a coupling agent, an inorganic filler, and the like may be added as long as the characteristics are not impaired.

The content of tetragonal zirconia particles in the transparent composite is preferably 1% by weight or more and 80% by weight or less, more preferably 10% by weight or more and 80% by weight or less, and further preferably 10% by weight or more and 50% by weight or less. It is as follows.
Here, the reason why the content of the tetragonal zirconia particles is limited to 1% by weight or more and 80% by weight or less is that the lower limit of 1% by weight is the minimum value of the addition rate that can improve the refractive index and mechanical properties. On the other hand, 80% by weight of the upper limit is the maximum value of the addition rate that can maintain the characteristics (flexibility and specific gravity) of the resin itself.

In this transparent composite, when the content of tetragonal zirconia particles is 25% by weight, the visible light transmittance is preferably 90% or more, more preferably 92% or more when the optical path length is 1 mm.
This visible light transmittance varies depending on the content of tetragonal zirconia particles in the transparent composite. When the content of tetragonal zirconia particles is 1% by weight, it is 95% or more, and when the content of tetragonal zirconia particles is 40% by weight. 80% or more.

Since the refractive index of the tetragonal zirconia particles is 2.15, by dispersing the tetragonal zirconia particles in the resin, the refractive index of the acrylate resin and the silicone resin is about 1.4, and the refractive index of the epoxy resin is 1.5. Compared with the degree, the refractive index of the resin can be further improved.
Further, tetragonal zirconia particles can be expected to improve the toughness value due to martensitic transformation as compared with monoclinic zirconia particles, and also have high toughness and hardness, and are suitable for improving the mechanical properties of the composite.
Further, since the tetragonal zirconia particles are nano-sized particles, even when they are combined with a resin, light scattering is small and the transparency of the composite material can be maintained.

In this optical lens, the flat transparent substrate 1 and the convex lens portion 2 are made of a transparent composite in which tetragonal zirconia particles having a dispersed particle diameter of 1 nm or more and 20 nm or less are dispersed in a transparent resin. Is maintained, and the refractive index and toughness are also improved.
Thereby, transparency, refractive index, thermal stability, hardness and weather resistance are improved, and thus reliability is improved over a long period of time.

Next, a method for manufacturing this optical lens will be described.
When producing this optical lens, the following zirconia transparent dispersion is used.
"Zirconia transparent dispersion"
This zirconia transparent dispersion is a dispersion containing tetragonal zirconia particles having a dispersed particle diameter of 1 nm or more and 20 nm or less and a dispersion medium.
The dispersion medium basically contains at least one of water, an organic solvent, a liquid resin monomer, and a liquid resin oligomer.

  Examples of the organic solvent include alcohols such as methanol, ethanol, 2-propanol, butanol, and octanol, ethyl acetate, butyl acetate, ethyl lactate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, and γ-butyrolactone. Esters such as diethyl ether, ethylene glycol monomethyl ether (methyl cellosolve), ethylene glycol monoethyl ether (ethyl cellosolve), ethylene glycol monobutyl ether (butyl cellosolve), ethers such as diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, acetone, Methyl ethyl ketone, methyl isobutyl ketone, acetylacetone, cyclohexanone, etc. Amides, aromatic hydrocarbons such as benzene, toluene, xylene and ethylbenzene, and amides such as dimethylformamide, N, N-dimethylacetoacetamide and N-methylpyrrolidone are preferably used. One of these solvents or Two or more kinds can be used.

As the liquid resin monomer, acrylic or methacrylic monomers such as methyl acrylate and methyl methacrylate, and epoxy monomers are preferably used.
Moreover, as said liquid resin oligomer, a urethane acrylate oligomer, an epoxy acrylate oligomer, an acrylate oligomer, etc. are used suitably.

The content of tetragonal zirconia particles is preferably 1% by weight or more and 70% by weight or less, more preferably 1% by weight or more and 50% by weight or less, and further preferably 5% by weight or more and 30% by weight or less.
Here, the reason why the content of the tetragonal zirconia particles is limited to 1% by weight or more and 70% by weight or less is that this range is a range in which the tetragonal zirconia particles can take a good dispersion state, and the content is 1% by weight. If it is less than%, the effect as tetragonal zirconia particles is reduced, and if it exceeds 70% by weight, gelation and aggregation precipitation occur, and the characteristics as a dispersion are lost.

In addition to the above, the zirconia transparent dispersion may contain other inorganic oxide particles, a dispersant, a dispersion aid, a coupling agent, a resin monomer, and the like as long as the characteristics are not impaired.
As inorganic oxide particles other than tetragonal zirconia particles, monoclinic or cubic zirconia particles, titanium oxide, zinc oxide, cerium oxide, tin oxide, antimony-added tin oxide (ATO), tin-added indium oxide (ITO) Etc.
Examples of the dispersant include phosphate ester type dispersants.

In the zirconia transparent dispersion, when the content of tetragonal zirconia particles is 5% by weight, the visible light transmittance is preferably 90% or more, more preferably 95% or more when the optical path length is 10 mm.
The visible light transmittance varies depending on the content of tetragonal zirconia particles. When the content of tetragonal zirconia particles is 1% by weight, it is 95% or more, and when the content of tetragonal zirconia particles is 40% by weight, it is 80% or more. It is.

"Production method of optical lens"
The above-described zirconia transparent dispersion and resin monomers and oligomers are mixed using a mixer or the like to prepare a resin composition in a state where it is easy to flow.
Next, the resin composition is molded into a predetermined shape using a mold, and a molded body in which a minute convex lens portion is formed on the surface (one surface) of a base material made of a flat resin composition is produced. .
Next, the molded body is heated or irradiated with ultraviolet rays or infrared rays, and the molded body is cured to obtain an optical lens.

Here, when the resin monomer or oligomer has a reactive carbon double bond (C = C), it can be polymerized / resinized simply by mixing.
In particular, there are various methods for curing a resin composition containing an ultraviolet (UV) curable resin such as an acrylic resin. Typically, a radical polymerization reaction initiated by heating or light irradiation is used. Mold molding method, transfer molding method and the like. Examples of the radical polymerization reaction include a polymerization reaction by heat (thermal polymerization), a polymerization reaction by light such as ultraviolet rays (photopolymerization), a polymerization reaction by gamma rays, or a method in which a plurality of these are combined.

When a silicone resin is used, an optical lens can be produced by placing one or more types of organopolysiloxane, a curing agent and a catalyst in a mold and thermally curing in the mold. As the thermosetting reaction, reactions such as condensation crosslinking, peroxide crosslinking, and platinum addition crosslinking can be used. In particular, thermosetting by an addition polymerization reaction using a platinum catalyst is preferable.
As described above, the optical lens of this embodiment shown in FIG. 1 can be manufactured.

As described above, according to the optical lens of this embodiment, a transparent composite in which tetragonal zirconia particles having a dispersed particle diameter of 1 nm or more and 20 nm or less are dispersed in a resin is used, and a flat plate shape made of this transparent composite is used. Since the minute convex lens portion 2 is formed on the surface of the transparent substrate 1, the light transmittance, refractive index, thermal stability, hardness and weather resistance can be improved.
Therefore, an optical lens excellent in high light transmittance, high refractive index, high thermal stability, high hardness, and weather resistance can be provided.

“Second Embodiment”
FIG. 2 is a cross-sectional view showing a microlens array (optical component) according to a second embodiment of the present invention.
This microlens array has a configuration in which a plurality of convex lens portions 2 are formed in a matrix on the surface (one surface) of the transparent substrate 1.
This microlens array can achieve the same effect as the optical lens of the first embodiment.
In addition, this microlens array is excellent in high light transmittance, high refractive index, high thermal stability, high hardness and weather resistance, so that it can be used in copying machines, printers, etc. that require high resolution and high reliability. Suitable for OA equipment and the like.

EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention concretely, this invention is not limited by these Examples.
"Example 1"
(Preparation of zirconia transparent dispersion)
To a zirconium salt solution in which 2615 g of zirconium oxychloride octahydrate is dissolved in 40 L (liter) of pure water, dilute ammonia water in which 344 g of 28% ammonia water is dissolved in 20 L of pure water is added with stirring, and the zirconia precursor slurry is added. It was adjusted.
Next, an aqueous sodium sulfate solution in which 300 g of sodium sulfate was dissolved in 5 L of pure water was added to this slurry with stirring. The amount of sodium sulfate added at this time was 30% by weight with respect to the zirconia converted value of zirconium ions in the zirconium salt solution.

Next, this mixture was dried in the air at 130 ° C. for 24 hours using a dryer to obtain a solid.
Next, the solid was pulverized with an automatic mortar or the like and then baked at 500 ° C. for 1 hour in the air using an electric furnace.
Next, the fired product is put into pure water, stirred to form a slurry, washed using a centrifuge, and after sufficiently removing the added sodium sulfate, dried in a dryer, Tetragonal zirconia particles were prepared.
Next, 87 g of toluene as a dispersion medium and 3 g of CS-141E (manufactured by Asahi Denka Kogyo Co., Ltd.) as a dispersion medium are added to 10 g of this tetragonal zirconia particles, and dispersed by a bead mill using 0.1 mmφ zirconia beads. A zirconia transparent dispersion (Z1) having a dispersed particle diameter of 1 nm or more and 20 nm or less was prepared.

(Production of optical lens)
To 100 g of the above zirconia transparent dispersion (Z1), 5 g of 1,6-hexanediol diacrylate, 2.5 g of pentaerythritol triacrylate, 2 g of pentaerythritol tetraacrylate, 0.5 g of benzoyl peroxide as a polymerization initiator are added, and resin is added. A composition was prepared.
Next, this resin composition was poured into an optical lens mold and cured by heating at 60 ° C. for 5 hours and then at 120 ° C. for 2 hours to produce the optical lens of Example 1. The content of zirconia in this optical lens was 50% by weight.

"Example 2"
To 100 g of the zirconia transparent dispersion (Z1) of Example 1, 10 g of silicone oil (a mixture of methylhydrogenpolysiloxane and organopolysiloxane each having vinyl groups at both ends) was added, and chloroplatinic acid was added to silicone oil 100. It added so that it might be set to 20 ppm with respect to a weight part, Then, it removed solvent by vacuum drying, and produced the resin composition.
Next, this resin composition was poured into a mold for optical lenses and cured by heating at 150 ° C. for 2 hours to produce an optical lens of Example 2. The content of zirconia in this optical lens was 50% by weight.

"Example 3"
To 100 g of the zirconia transparent dispersion (Z1) of Example 1, 7 g of epoxy resin: Epicoat 828 and 3 g of EpiCure 3080 (both manufactured by Japan Epoxy Resins Co., Ltd.) were added, and the solvent was removed by vacuum drying. A resin composition was prepared.
Next, this resin composition was poured into a mold for optical lenses and cured by heating at 80 ° C. for 30 minutes to produce an optical lens of Example 3. The content of zirconia in this optical lens was 50% by weight.

"Comparative Example 1"
The zirconia dispersion of Comparative Example 1 was subjected to dispersion treatment according to Example 1 except that RC-100 containing monoclinic and tetragonal zirconia particles (manufactured by Daiichi Rare Element Co., Ltd.) was used as the zirconia particles. (Z2) was produced. Incidentally, the average dispersed particle diameter of the zirconia particles was 100 nm.
To this zirconia dispersion (Z2), 1,6-hexanediol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, and benzoyl peroxide as a polymerization initiator used in Example 1 were added to prepare a resin composition. . The content of zirconia in the resin composition was 50% by weight.
Subsequently, this resin composition was processed according to Example 1, and the optical lens of the comparative example 1 was produced.

"Comparative Example 2"
To the zirconia dispersion (Z2) of Comparative Example 1 were added the silicone oil used in Example 2 (a mixture of methylhydrogenpolysiloxane and an organopolysiloxane having vinyl groups at both ends) and chloroplatinic acid, The solvent was removed by vacuum drying to prepare a resin composition. The content of zirconia in the resin composition was 50% by weight.
Subsequently, this resin composition was processed according to Example 2, and the optical lens of the comparative example 2 was produced.

“Comparative Example 3”
Epoxy resin used in Example 3: Epicoat 828 and EpiCure 3080 as a curing agent were added to the zirconia dispersion liquid (Z2) of Comparative Example 1, and the solvent was removed by vacuum drying to prepare a resin composition. The content of zirconia in the resin composition was 50% by weight.
Subsequently, this resin composition was processed according to Example 3, and the optical lens of the comparative example 3 was produced.

“Comparative Example 4”
A resin composition was prepared according to Comparative Example 1. However, the content of zirconia particles in the resin composition was 2% by weight.
Subsequently, this resin composition was processed according to Example 1, and the optical lens of the comparative example 4 was produced.

“Comparative Example 5”
A resin composition was prepared according to Comparative Example 2. However, the content of zirconia particles in the resin composition was 2% by weight.
Subsequently, this resin composition was processed according to Example 2, and the optical lens of the comparative example 5 was produced.

“Comparative Example 6”
A resin composition was prepared according to Comparative Example 3. However, the content of zirconia particles in the resin composition was 2% by weight.
Subsequently, this resin composition was processed according to Example 3, and the optical lens of the comparative example 6 was produced.

"Evaluation of optical lenses"
With respect to each of the optical lenses of Examples 1 to 3 and Comparative Examples 1 to 6, three points of visible light transmittance, refractive index and hardness were evaluated by the following apparatus or method.

(1) Visible light transmittance Visible light transmittance was measured using a spectrophotometer (manufactured by JASCO Corporation).
Here, the measurement sample was a bulk body having a size of 100 × 100 × 1 mm, the transmittance of 80% or more was “◯”, and the less than 80% was “×”.
(2) Refractive index: Measured with an Abbe refractometer in accordance with Japanese Industrial Standards: JIS K 7142 “Plastic Refractive Index Measuring Method”.
Here, on the basis of the resin to which zirconia is not added, a case where the refractive index is improved by 0.05 or more is indicated by “◯”, and a case where the refractive index is improved by less than 0.05 is indicated by “X”.

(3) Hardness JIS-A hardness was measured using a durometer in accordance with Japanese Industrial Standards: JIS K 7215 “Plastic Durometer Hardness Test Method”.
Here, it is produced using the resin composition of Comparative Examples 1 to 3 using the zirconia dispersion (Z2) of Comparative Example 1, and based on the hardness of the optical lens having a zirconia content of 50% by weight, A case where the value is higher than the reference value is “◯”, and a case where the value is lower than the reference value is “x”.
The above evaluation results are shown in Table 1.

According to these evaluation results, in Examples 1 to 3, it was found that the visible light transmittance, refractive index, and hardness were all good.
On the other hand, in Comparative Examples 1-6, any one of visible light transmittance, refractive index, and hardness was inferior to Examples 1-3.

  The composition for optical lenses of the present invention contains tetragonal zirconia particles having a dispersed particle diameter of 1 nm or more and 20 nm or less, thereby maintaining transparency and improving refractive index and toughness. Because there are cameras, film-integrated cameras such as film with lens, various cameras such as video cameras, optical pickups such as CD, CD-ROM, MO, CD-R, CD-Video, DVD, copying machines, printers, etc. The effect is great not only in various devices such as OA devices but also in various industrial fields to which optical lenses are applied.

It is sectional drawing which shows the optical lens of the 1st Embodiment of this invention. It is sectional drawing which shows the microlens array of the 2nd Embodiment of this invention.

Explanation of symbols

1 Transparent base material 2 Convex lens part

Claims (5)

An optical lens composition comprising tetragonal zirconia particles having a dispersed particle diameter of 1 nm or more and 20 nm or less and a transparent resin .   2. The optical lens composition according to claim 1, wherein the tetragonal zirconia particles are dispersed in a resin.   The composition for optical lenses according to claim 1 or 2, wherein the content of the tetragonal zirconia particles is 1 wt% or more and 80 wt% or less.   An optical lens comprising at least a light transmission region comprising the optical lens composition according to claim 1, 2 or 3.   An optical component comprising the optical lens according to claim 4.

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