WO2006051699A1

WO2006051699A1 - Resin composition and optical device using same

Info

Publication number: WO2006051699A1
Application number: PCT/JP2005/019891
Authority: WO
Inventors: Masako Kikuchi
Original assignee: Konica Minolta Opto, Inc.
Priority date: 2004-11-10
Filing date: 2005-10-28
Publication date: 2006-05-18
Also published as: JPWO2006051699A1

Abstract

Disclosed is a thermoplastic resin composition wherein inorganic particles are dispersed in a resin matrix. The thermoplastic resin composition is characterized in that the refractive index of the inorganic particles is within a range of 1.3-2.3, and the resin composition has a light transmittance of not less than 70% per 3 mm of optical path length and a linear expansion coefficient of not more than 5 × 10-5 (/˚C).

Description

Resin composition and optical element using the same

Technical field

[0001] The present invention is suitably used as a lens, a filter, a grating, an optical fiber, a flat optical waveguide, etc., and is excellent in transparency and has a small change in size and refractive index due to temperature. The present invention relates to a composition molded body.

Background art

[0002] Optical pickups are used for information devices such as players, recorders, and drives that read and record information on MO, CD, DVD, and other optical information recording media (hereinafter simply referred to as media!). A device is provided. The optical pickup device includes an optical element unit that irradiates a medium with light having a predetermined wavelength generated by a light source, and receives the reflected light with a light receiving element. The optical element unit transmits the light to a reflection layer of the medium. It has an optical element such as a lens for condensing light by the light receiving element.

[0003] The optical element of the optical pickup device is preferably made of plastic as a material because it can be manufactured at low cost by means such as injection molding. As a plastic applicable to an optical element, a copolymer of cyclic olefin and α-age refin (for example, Patent Document 1) is known.

[0004] An optical element unit using plastic as a material is required to be a substance having optical stability such as a glass lens. For example, optical plastic materials such as annular olefins have significantly improved the change in refractive index due to water absorption, which is extremely low in water absorption compared to conventional plastics for lenses. However, the temperature dependence of optical properties has not been solved yet, and the temperature dependence of the linear expansion coefficient and refractive index is one order of magnitude greater than that of inorganic glass.

[0005] As one method for improving the disadvantages of the optical plastic material as described above, a method using a fine particle filler has been proposed.

For example, in Patent Documents 2 to 8, as a method for reducing the temperature dependence of refractive index dnZdT, a fine particulate material with dnZdT> 0 is separated from a polymeric host material with dnZdT <0. Scattered by an optical product has been proposed (e.g., see Patent Document 2-8.) ₀ However, for example, as shown in equation 2 described in Patent Document 6, for small to dnZdT host material 50% reduction In order to achieve this, it has been shown that it is necessary to mix 40% by mass or more of inorganic fine particles, and such a resin material mixed with a large amount of inorganic fine particles has the disadvantage of high specific gravity and low transparency. . In addition, when the addition amount is large in this way, there is a problem that the inorganic fine particles dispersed in the resin aggregate and the performance changes when stored for a long period of time. Thus, a resin material suitable for practical use is provided. However, this is the current situation.

Patent Document 9 proposes a resin composition molded article in which ultrafine particles are dispersed in order to reduce the rate of dimensional change before and after the heating test. However, in the technique disclosed herein, It is insufficient to improve the disadvantages of the above-mentioned optical plastic materials while maintaining transparency that is satisfactory for use.

Patent Document 1 Japanese Patent Application Laid-Open No. 2002-105131 (Page 4)

Patent Document 2 JP 2002-207101 (Claims)

Patent Document 3 JP 2002-240901 A (Claims)

Patent Document 4 JP 2002-241560 A (Claims)

Patent Document 5 JP 2002-241569 A (Claims)

Patent Document 6 Japanese Patent Laid-Open No. 2002-241592 (Claims)

Patent Document 7 JP 2002-241612 A (Claims)

Patent Document 8 JP 2002-303701 A (Claims)

Patent Document 9 Japanese Unexamined Patent Application Publication No. 2003-155355 (Claims)

Disclosure of the invention

An object of the present invention is to provide a thermoplastic resin composition molded article which is excellent in transparency and has a small rate of change in size and refractive index due to temperature.

In order to achieve the above object, one aspect of the present invention is a resin composition in which inorganic fine particles are dispersed in a resin matrix, and the refractive index of the inorganic fine particles is 1.3 to 2.3. The light transmittance per 3 mm of the optical path length of the resin composition is 70% or more and the linear expansion coefficient is 5 X 10 ^_5 (Z ° C) or less. It is in the thermoplastic rosin composition. BEST MODE FOR CARRYING OUT THE INVENTION

[0007] The object of the present invention is achieved by the following configurations.

(1) A resin composition in which inorganic fine particles are dispersed in a resin matrix, wherein the refractive index of the inorganic fine particles is in the range of 1.3 to 2.3, and the optical path of the resin composition length 3mm and by those have enough light transmittance of 70% or more, and the linear expansion coefficient of ^{5 X 10 _5 (Z ° C} ) thermoplastic榭脂composition characterized der Rukoto below.

(2) The resin composition according to (1), wherein the resin composition has a light transmittance of 85% or more per 3 mm of optical path length at the d-line wavelength.

(3) A resin composition in which inorganic fine particles are dispersed in a resin matrix, wherein the resin composition has a light transmittance of 70% or more at an optical path length of 3 mm at the d-line wavelength, A thermoplastic resin composition, wherein the inorganic fine particles are plate-shaped or needle-shaped.

(4) The inorganic fine particles are plate-like, and the average size thereof has a thickness in the range of 0.1 to: LOnm and an aspect ratio of 3 to: LOOO. The rosin composition.

(5) The inorganic fine particles are needle-shaped, the average value of the shortest diameter of the inorganic fine particles is 0.1 to 10 nm, and the aspect ratio is in the range of 3 to 5000. The rosin composition.

(6) The resin is at least one selected from acrylic resin, cyclic olefin resin, polycarbonate resin, polyester resin, polyether resin, polyamide resin and polyimide resin. The coffin composition according to any one of (1) to (5).

(7) The deviation of (1) to (6) above, wherein the content of the inorganic fine particles is 0.01% by mass or more and 30% by mass or less with respect to the mass of the resin composition. The resin composition according to claim 1.

(8) An optical element formed by using the thermoplastic resin composition according to any one of (1) to (7) above.

Hereinafter, the best mode for carrying out the present invention will be described in detail.

[0009] The present inventors have found that the problem with optical plastics is that the environmental dependence of optical properties is large, especially that the temperature dependence of linear expansion coefficient and refractive index is one digit or more larger than that of inorganic glass. In order to solve this problem, a molded product of a resin composition in which various inorganic fine particles were dispersed in a resin matrix was prepared and studied earnestly. As a result, it was discovered that a resin composition molded body that can greatly reduce the linear expansion coefficient and maintain the transparency as an optical element can be produced without adding a large amount of inorganic fine particles. Furthermore, it has been found that the temperature dependence of the refractive index is greatly improved by reducing the linear expansion coefficient.

[0010] Specifically, the present inventors have found that the above problems can be solved when the inorganic fine particles dispersed in the resin matrix are plate-like or needle-like, and have reached the present invention. Inorganic fine particles with a high aspect ratio, such as plate or needle, bind strongly to the matrix resin and greatly improve dimensional stability. This makes it possible to reduce the linear expansion coefficient. Furthermore, by reducing the size of the plate-like or needle-like particles to the order of nanometers, the linear expansion coefficient can be reduced even with a small amount of addition, and as an optical material. I was able to maintain the transparency of this. Even if the shape of the inorganic fine particles dispersed in the resin matrix has a high aspect ratio compared to that of a plate or needle, other than the inorganic fine particles, surface modification is applied to the inorganic fine particles to interact with the matrix resin. By reinforcing the strength, it is possible to provide a resin composition molded article having a small linear expansion coefficient. In this case, it is necessary to increase the amount of inorganic fine particles added compared to the case of plate-like or needle-like particles. In this case as well, the transparency as an optical material is maintained, and the lightness that is the merit of optical plastics. In order to maintain this, the amount of inorganic fine particles added is desirably 30% by mass or less with respect to the mass of the resin composition molded body. Further, when the inorganic fine particles are those having an aspect ratio of 5 or less, if the addition amount is 9% by mass or less, a sufficient effect cannot be obtained with respect to the problem in the present invention. It is desirable to be within the range of 10-30% by mass.

[0011] Further, the present inventors have found that when the refractive index of the inorganic fine particles is 1.3 to 2.3, it is possible to maintain transparency as an optical material that is a subject of the present invention. did. The refractive index of inorganic fine particles is described in Optical Engineering Handbook (Asakura Shoten)! However, either the measured value or the literature value of the refractive index at the d-line wavelength of the bulk material having the same composition as the inorganic fine particles is 1.3 to 2. It has been found that the object of the present invention can be achieved within the range of 3. Transparency required for optical materials Depending on the application, the transparency required for the main optical applications can be obtained by setting the light transmittance per 3 mm of the optical path length at the d-line wavelength of the resin composition molded body, which is an optical material, to 70% or more. Furthermore, by setting the light transmittance to 85% or more, the transparency required for lens use can be obtained.

Hereinafter, details of the present invention will be described.

[0013] << Thermoplastic resin >>

In the present invention, the matrix resin in which inorganic fine particles are dispersed is a thermoplastic resin. As the thermoplastic resin used in the present invention, an acrylic resin, a cyclic olefin resin, a polycarbonate resin, a polyester resin, and a polyether are acceptable as long as it is a transparent resin material generally used as an optical material. It is preferable to use a resin, a polyamide resin, a polyimide resin. Specific examples include the compounds described in Table 1 of JP-A-2003-73559, and preferred compounds are shown in Table 1.

[0014] [Table 1]

[0015] As a thermoplastic resin particularly preferably used in the present invention, cycloolefin resin

(ZONEX (Nippon Zeon), Arton (JSR), Apel (Mitsui Chemicals), etc. are not limited to these, and it is also preferable to use other resins that are compatible with these resins. .

[0016] << Inorganic fine particles >> The inorganic fine particles most preferably used in the present invention are plate-like or needle-like inorganic fine particles. The plate-like fine particles in the present invention are particles having at least two faces facing each other, and the average force of the equivalent circle diameter (diameter) of this face is at least twice the average value of the distance between the faces of the two faces. Means that. When the average value of the distance between two surfaces is defined as the average thickness, the thickness is preferably within a range of 0.1 to LOnm. If the thickness is less than 0.1 nm, it is difficult to disperse the inorganic fine particles, so that the desired performance may not be obtained. If the thickness exceeds lOnm, the obtained resin composition molded article Transparency may be reduced. The average aspect ratio is preferably in the range of 3 to L000, more preferably in the range of 5 to 300. The aspect ratio in this case means (average value of equivalent circle diameter (diameter) of the surface) / (average thickness). If the aspect ratio is less than 3, the effect of the present invention of reducing the linear expansion coefficient by adding a small amount of inorganic fine particles may not be sufficiently exhibited. Molding of a resin composition obtained when the aspect ratio exceeds 1000 The transparency of the body may be reduced.

[0017] The needle-shaped inorganic fine particles in the present invention refer to those in which the longest diameter of the fine particles is twice or more the shortest diameter. Therefore, rod-like and ellipsoids are also included in the needle-like fine particles of the present invention. In the present invention, the average value of the shortest diameters of the fine particles is preferably within the range of 0.1 to LOnm. If this value is less than 0.1 nm, it may be difficult to obtain the desired performance due to the difficulty in dispersing the inorganic fine particles, and if it exceeds lOnm, the transparency of the resulting molded resin composition May decrease. The average aspect ratio is preferably in the range of 3 to 2000, more preferably in the range of 5 to 500. The average aspect ratio in this case is given by the average value of (the longest diameter of the fine particles, the diameter) Z (the shortest diameter of the fine particles, the diameter). Even in this case, if the aspect ratio is less than 3, the effect of the present invention may not be sufficiently exhibited if the linear expansion coefficient is reduced by adding a small amount of inorganic fine particles. There is a risk that the transparency of the molded product of the composition is lowered.

[0018] The content of the plate-like or needle-like inorganic fine particles most preferably used in the present invention is not particularly limited as long as the effects of the present invention can be exhibited, and thermoplastic resin and inorganic fine particles are not limited. However, if the content of the inorganic fine particles is high, optical properties such as light transmittance deteriorate due to light scattering, which is not preferable. Therefore, inorganic fine particles The content of the particles is preferably 0.01% by mass or more and 30% by mass or less with respect to the mass of the molded resin composition in which inorganic fine particles are dispersed in the matrix resin. More preferably, it is 0.01 mass% or more and 20 mass% or less, More preferably, it is 0.01 mass% or more and 10 mass% or less.

[0019] Even if the shape of the inorganic fine particles dispersed in the resin matrix is other than the inorganic fine particles having a high aspect ratio such as a plate shape or a needle shape, the inorganic fine particles are subjected to surface modification to form a matrix resin. It is possible to provide a resin composition composition having a low coefficient of linear expansion by strengthening the interaction. In this case, it is necessary to increase the amount of inorganic fine particles added compared to the case of plate-like or needle-like particles, but even in this case, transparency as an optical element is maintained, which is an advantage of optical plastics. In order to maintain light weight, the amount of inorganic fine particles added is desirably 30% by mass or less based on the mass of the resin composition molded body. In addition, when the inorganic fine particles are particles having an aspect ratio of 3 or less, if the addition amount is 9 mass% or less, a sufficient effect cannot be obtained for the problem in the present invention. Is preferably in the range of 10 to 30% by mass. In this case, the average particle size of the inorganic fine particles is preferably 1 nm or more and 30 nm or less, preferably 1 nm or more, more preferably 20 nm or less, and further preferably 1 nm or more and 10 nm or less. If the average particle size is less than 1 nm, it is difficult to disperse the inorganic fine particles, so that the desired performance may not be obtained. If the average particle size exceeds 30 nm, the resulting thermoplastic material composition becomes cloudy. There is a risk that transparency will be reduced. The average particle diameter here refers to the diameter when converted to a sphere having the same volume as the particle.

[0020] In the present invention, the distribution of the inorganic fine particles used in the present invention is not particularly limited! / ヽ 1S In order to more efficiently express the effects of the present invention, it is more preferable than those having a wide distribution. Those having a relatively narrow distribution are preferably used.

[0021] In addition, when the difference in refractive index between the inorganic fine particles and the resin in the resin matrix is large, optical properties such as light transmittance due to light scattering are likely to deteriorate, and therefore the inorganic used in the present invention. The refractive index of the fine particles is preferably in the range of 1.3 to 2.3, more preferably in the range of 1.3 to 2.0, and still more preferably in the range of 1.3 to 1.7. Is within. The index of refraction of inorganic fine particles is described in the Optical Engineering Nord Book (Asakura Shoten)! It can be measured by the method. Reference values of the refractive index at the d-line wavelength of the Balta body having the same composition as the inorganic fine particles may be referred to.

[0022] The type of plate-like fine particles preferably used in the present invention is not particularly limited, and examples thereof include layered silicates. The layered silicate is an inorganic mineral in which a large number of fine flaky crystals having a thickness of about 1 nm and an average aspect ratio of about 20 to 200 are aggregated by ionic bonds. By solving this agglomerated structure by ionic or physical means and uniformly dispersing the flaky crystals in the resin, the rate of change in size and refractive index with temperature, which is the object of the present invention, is small. ! A molded resin composition can be obtained. Layered silicate refers to a silicate mineral having exchangeable cations between layers. The type of layered silicate is not particularly limited, but it is a synthetic mica such as swellable my strength (mica), smetite series such as montmorillonite, sabonite, hectorite, piderite, stevensite, nontronite. In addition to clay minerals, there are vermiculite, nor, leucite, and the like, and natural or synthesized ones can be preferably used.

Furthermore, examples of the inorganic fine particles preferably used in the present invention include metal oxide fine particles. Metals constituting the metal oxide are Li, Na, Mg, Al, Si, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Rb, Sr, Y, Nb , Zr, Mo, Ag, Cd, In, Sn, Sb, Cs, Ba, La, Ta, Hf, W, Ir, Tl, Pb, Bi and one or more selected from the group consisting of rare earth metals Metal oxides that are metals of the above can be used, and phosphates, sulfates, carbonates and the like can also be used.

[0023] As the inorganic fine particles of the present invention, fine particles having a semiconductor crystal composition can also be preferably used. Although there is no restriction | limiting in particular in this semiconductor crystal composition, What does not produce absorption, light emission, fluorescence, etc. in the wavelength range used as an optical element is desirable. Specific examples of the composition include simple elements of Group 14 elements of the periodic table such as carbon, kaen, germanium and tin, periodic elements of Group 15 elements of the periodic table such as phosphorus (black phosphorus), periodic periods of selenium, tellurium and the like. Table 16 element simple substance, several periodic table such as silicon carbide (SiC), group 14 element power compound, tin oxide (IV) (Sn02), tin sulfate (IV, IV) (Sn (II ) Sn (IV) S3), sulfurized tin (IV) (SnS2), sulfurized tin (Π) (SnS), tin selenide (Π) (SnSe), tin telluride (Π) (SnTe), Compounds of periodic table group 14 elements and periodic table group 16 elements such as lead sulfide (鉛) (PbS), selenium lead (Π) (PbSe), lead telluride (II) (PbTe) Boron nitride (BN), phosphorous boron (BP), boron arsenide (BAs), aluminum nitride (A1N), aluminum phosphide (A1P), aluminum arsenide (AlAs), aluminum antimonide (AlSb), gallium nitride (GaN ), Gallium phosphide (GaP), Gallium arsenide (GaAs), Gallium antimonide (GaSb), Indium nitride (InN), Indium phosphide (InP), Indium arsenide (InAs), Indium antimonide (InSb) Compounds of Group 13 and Periodic Table 15 (or III-V compound semiconductors), aluminum sulfate (A12S3), aluminum selenide (A12Se3), gallium sulfide (Ga2S3), selenium Periodic Table 13 elements and periodic table such as gallium phosphide (Ga2Se 3), gallium telluride (Ga2Te3), indium oxide (In203), indium sulfide (In2S3), indium selenide (In2Se3), indium telluride (ln2Te3) Periodic table of compounds with group 16 elements, such as thallium (I) (T1C1), thallium bromide (I) (T1 Br), thallium iodide (I) (T1I) Compounds with Group 17 elements, zinc oxide (ZnO), zinc sulfide (ZnS), selenium-zinc (ZnSe), tellurium-zinc (Zn Te), cadmium oxide (CdO), zirconia cadmium (CdS), Cadmium selenide (CdSe), cadmium telluride (CdTe), mercury sulfide (HgS), mercury selenide (HgSe), mercury telluride (HgTe), etc. Compounds (or II-VI group compound semiconductors), arsenic sulfide (III) (As2S3), arsenic selenide (III) (As2Se3), tellurium arsenic (ΠΙ) (As2Te3), antimony sulfide (III) (Sb2S3) , Selenium-antimony (III) (S b2Se3), Tenorenol-antimony (III) (Sb2Te3), Bismuth sulfate (III) (Bi2S3), Bismuth selenide (III) (Bi2Se3), Tellurium Periodic table such as bismuth (III) (Bi2Te3) periodic table group 15 element and periodic table group 16 element, copper oxide (I) (Cu20), copper selenide (I) (Cu2Se) etc. Compound of group 11 element and group 16 element, copper chloride (I) (CuCl), copper bromide (I) (CuBr), copper iodide (I) (Cul), silver chloride (AgCl) , Compounds of Group 1 elements of the periodic table such as silver bromide (AgBr) and Group 17 elements of the periodic table, Group 10 elements of the periodic table such as nickel oxide (ニッケル) (NiO) and Group 16 of the periodic table Compounds with elements, compounds of Group 9 elements of periodic table such as cobalt (II) oxide (CoO), cobalt sulfide (II) (CoS) and Group 16 elements of periodic table, triiron tetroxide (Fe 304), Compounds of Group 8 elements of the periodic table such as iron (II) sulfide (FeS) and Group 16 elements of the periodic table, Group 7 elements of the periodic table such as manganese oxide (II) (MnO) and Group 16 elements of the periodic table Group 6 elements of the periodic table, such as compounds with molybdenum, molybdenum (IV) (MoS2), and acid tungsten (IV) (W02) And compounds of Group 16 elements of the Periodic Table, Group 5 elements of the Periodic Table such as vanadium oxide (II) (VO), acid-vanadium (IV) (V02), acid-tantalum (V) (Ta205), etc. Compounds with group 16 elements of the periodic table, compounds with group 4 elements of the periodic table such as titanium oxide (Ti02, Ti205, Ti203, Ti509, etc.), group 16 elements of the periodic table, magnesium sulfate (MgS), selenium匕 Magnesium (MgSe) and other compounds of Group 2 elements of the periodic table and Group 16 elements of the periodic table, cadmium oxide (II) Cu PIII (CdCr204), selenium cadmium (Π) Cu Pmu (III ) (CdCr2Se4), chalcogen spinels such as copper chloride (II) chromium (III) (CuCr2S4), selenium mercury (III) (HgCr2Se4), norium titanate (BaTi03), and the like. G. Schmid et al .; Ad v. Mater., 4, 494 (1991) [Reported! ΒΝ 75 (BF2) 15F15, D. Fenske et al .; Angew. Chem. Int. As reported in Ed. Engl., 29 （, p. 1452 (1990) !, Cul46Se73 (triethylphosphine) 22 has a well-defined structure, and semiconductor clusters are also exemplified.

[0024] The shape of the metal oxide fine particles, fine particles of phosphate, sulfate, carbonate, fine particles of semiconductor crystal composition, etc. is not particularly limited, but is a plate-like or acicular fine particle. It is more preferable. Examples of the metal oxide needle-shaped fine particles include NanoCeram (manufactured by Argonide), which is an alumina nanofiber having a diameter of 2 to 4 nm and an aspect ratio of 20 to 100.

[0025] Among the metal oxide fine particles, phosphate fine particles, sulfate fine particles, carbonate fine particles, and fine particles having a semiconductor crystal composition, silica (silicon oxide) having a small difference in refractive index from the matrix resin, calcium carbonate Since selecting aluminum phosphate improves the transparency of the resin composition, it is more preferable to use silica.

In addition, these fine particles may use one kind of inorganic fine particles or a combination of plural kinds of inorganic fine particles.

In the present invention, the inorganic fine particles according to the present invention are preferably subjected to a surface treatment.

[0027] For example, in the case of a layered silicate mineral having an exchangeable cation between layers, the exchangeable cation existing between the layers may be previously ion-exchanged with a cationic surfactant or the like. preferable. In particular, when a nonpolar resin such as cyclic olefin fin resin is used as the matrix resin, it is preferable to make the layers hydrophobic beforehand by, for example, cation exchange with a cationic surfactant. Therefore, high affinity is obtained between the layered silicate and the resin.

[0028] Examples of the surface modifier used for the surface treatment of inorganic fine particles such as metal oxide fine particles include, for example, tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, tetrahenoxysilane, methyltrimethoxysilane. Ethyltrimethoxysilane, propyltrimethoxysilane, methyltriethoxysilane, methyltriphenoxysilane, ethyltriethoxysilane, phenyltrimethoxysilane, 3-methylphenyltrimethoxysilane, dimethyldimethoxysilane, jetyljetoxy Examples include silane, diphenyldimethoxysilane, diphenyldimethoxysilane, trimethylmethoxysilane, triethylethoxysilane, triphenylmethoxysilane, and triphenylphenoxysilane.

These compounds have different characteristics such as reaction rate, and compounds suitable for surface modification conditions can be used. Further, only one type may be used or a plurality of types may be used in combination. Furthermore, the properties of the surface-modified fine particles obtained may vary depending on the compound used, and the affinity with the thermoplastic resin used in obtaining the material composition can be achieved by selecting the compound used for the surface modification. It is. The ratio of the surface modification is not particularly limited, but it is preferable that the ratio of the surface modifier is 10 to 99% by mass with respect to the fine particles after the surface modification. Is more preferable.

[0029] 《Mixture of resin and inorganic fine particles》

The resin composition of the present invention is composed of thermoplastic resin and inorganic fine particles, but the production method is not particularly limited. That is, a method of preparing thermoplastic coagulate and inorganic fine particles independently and then mixing them together, a method of producing thermoplastic coagulate under conditions in which pre-produced inorganic fine particles exist, Any method can be employed, such as a method of producing inorganic fine particles under the condition where plastic resin is present or a method of producing both thermoplastic resin and inorganic fine particles simultaneously. Specifically, for example, two solutions of a solution in which thermoplastic resin is dissolved and a dispersion in which inorganic fine particles are uniformly dispersed are mixed uniformly, and the solutions are arranged in a solution having poor solubility in thermoplastic resin. The target material The force capable of suitably mentioning the method of obtaining the material composition is not limited to this! / ヽ In the thermoplastic material composition of the present invention, the degree of mixing of the thermoplastic resin and the inorganic fine particles is particularly limited. Although not intended, in order to achieve the effect of the present invention more efficiently, it is desirable to mix uniformly. When the degree of mixing is insufficient, there is a concern that the optical properties such as the refractive index, Abbe number, and light transmittance may be affected, and the resin processability such as thermoplasticity and melt moldability is also adversely affected. There is a fear. The degree of mixing is considered to be affected by the production method, and it is important to select a method in consideration of the characteristics of the thermoplastic resin and inorganic fine particles used.

In order to more uniformly mix both the thermoplastic resin and the inorganic fine particles, a method of directly bonding the thermoplastic resin and the inorganic fine particles can be suitably used in the present invention.

[0030] The resin composition of the present invention is an optically excellent resin composition having a small coefficient of linear expansion, a small temperature dependence of the refractive index, and a high transparency, and further has thermoplasticity and Because it has Z or injection moldability, it is a thermoplastic material that has excellent moldability. This material with both excellent optical properties and moldability is a powerful property that cannot be achieved with the materials disclosed so far, and it also has a specific thermoplastic resin and a specific inorganic fine particle force. However, it is conceivable that it contributes to this characteristic.

[0031] << Other ingredients >>

When preparing the thermoplastic resin material of the present invention, various additives (also referred to as compounding agents) can be added to the resin composition molding step if necessary. There are no particular restrictions on the additives, but stabilizers such as antioxidants, heat stabilizers, light stabilizers, weather stabilizers, UV absorbers, near infrared absorbers, and oil refining agents such as lubricants and plasticizers. Examples thereof include: anti-clouding agents such as soft polymers and alcoholic compounds; coloring agents such as dyes and pigments; antistatic agents, flame retardants and fillers. These compounding agents can be used alone or in combination of two or more thereof, and the compounding amount thereof is appropriately selected within a range without impairing the effects described in the present invention. In the present invention, it is particularly preferable that the polymer contains at least a plasticizer or an antioxidant.

[0032] << Plasticizer >> The plasticizer is not particularly limited, however, phosphate ester plasticizer, phthalate ester plasticizer, trimellitic ester plasticizer, pyromellitic acid plasticizer, glycolate plasticizer, citrate ester Examples thereof include a plasticizer and a polyester plasticizer.

[0033] In the phosphate ester plasticizer, for example, triphenyl phosphate, tricresyl phosphate, credinole resin-nore phosphate, otachino resin-nore phosphate, diphenol-no-biphenyl phosphate, trioctyl phosphate, tributyl phosphate, etc. Examples of phthalate ester plasticizers include jetyl phthalate, dimethoxyethyl phthalate, dimethyl phthalate, dioctyl phthalate, dibutyl phthalate, di-2-ethyl hexyl phthalate, butyl benzyl phthalate, diphenyl phthalate, and dicyclohexyl phthalate. In the case of pyromellitic acid ester plasticizers such as tributyl trimellitate, triphenyl trimellitate, triethyl trimellitate, etc. Examples of glycolate plasticizers such as tetrabutyl pyromellitate, tetraphenyl bimellitate, tetraethyl pyromellitate, and the like include triacetin, tributyrin, ethyl phthalyl ethyl glycolate, methyl phthalyl ethyl dallicolate, butyl phthalate For example, tributyl citrate, tri-n-butyl citrate, acetyl acetyl citrate, acetiltyl n-butyl citrate, acetyl tri-n- (2— Ethylhexyl) citrate and the like.

[0034] << Antioxidant >>

The antioxidant used in the present invention will be described.

[0035] Examples of the antioxidant are phenolic antioxidants, phosphorus antioxidants, phenolic antioxidants, etc. Among them, phenolic antioxidants, especially alkyl Substituted phenolic acid oxidants are preferred. By blending these antioxidants, it is possible to prevent coloration and strength reduction of the lens due to oxidative deterioration during molding without reducing transparency, heat resistance and the like. These antioxidants can be used alone or in combination of two or more, and the amount of the antioxidant is appropriately selected within a range not impairing the object of the present invention. 100 mass of the polymer according to the present invention Preferably it is 0.001-5 mass parts with respect to a part, More preferably, it is 0.01-1 mass part.

[0036] As the phenolic acid rust inhibitor, conventionally known ones can be used, for example, 2-tube. 6- (3-tert-butyl 2-hydroxy-5-methylbenzyl) 4-methylphenol acrylate, 2, 4 di-tert-amyl 6- (1— (3,5-di-tert-amyl 2-hydroxy Acetalyl compounds described in Japanese Patent Application Laid-Open No. 63-179953 and Japanese Patent Application Laid-Open No. 1-168643, such as thiol) ethyl) phenyl acrylate, etc .; Octadecyl-3- (3, 5- t-butyl 4-hydroxyphenol) propionate, 2, 2'-methylene bis (4-methyl 6-t-butylphenol), 1, 1,3 tris (2-methyl 4-hydroxy--5- t-butylphenol ) Butane, 1, 3, 5 Trimethyl 2, 4, 6 Tris (3,5 Di-tert-butyl 4-hydroxybenzyl) benzene, Tetrakis (Methylene-l- (3 ', 5' Di-tert-butyl-^-hydroxyphenol propionate) )) Methane [ie Pentaerythrimethylte Lakis (3- (3,5-di-tert-butyl-4-hydroxyphenylpropionate))], triethylene glycol bis (3- (3-tert-butyl 4-hydroxy-1-5-methylphenyl) propionate) Alkyl-substituted phenol compounds; 6- (4-hydroxy-3,5 di-tert-butylanilino) -2,4 bisoctylthio-1,3,5 triazine, 4 bisoctylthio 1,3,5 triazine, 2-octylthio 4, 6 Bis — (3,5 di-t-butyl-4-oxy-lino) — 1, 3, 5 Triazine-containing phenolic compounds such as triazine;

[0037] There are no particular limitations on the phosphorus-based anti-oxidation agent as long as it is commonly used in the general oil industry, for example, triphenylphosphite, diphenylisodecylphosphite, phenoldiisodecyl. Phosphite, tris (norphenol) phosphite, tris (dinolephenol) phosphite, tris (2,4 di-t-butylphenol) phosphite, 10- (3,5- t-butyl 4-hydroxybenzyl) 9, 10 dihydro-9-oxa 10 phosphaphenanthrene 10 monophosphite compounds such as oxide; 4, 4'-butylidene-bis (3-methyl-6-t-butylphenol- And diphosphite compounds such as 4,4'-isopropylidene monobis (phenol didialkyl (C12-C15) phosphite). Of these, tris (noyulphele) phosphite, tris (dinoufulfer) phosphite, and tris (2,4 di-t-butylphenol) phosphite are particularly preferred, which prefer monophosphite compounds. .

[0038] Examples of iow antioxidants include dilauryl 3, 3 thiodipropionate and dimi. Listyl 3, 3'—thiodipropionate, distearyl 3, 3-thiodipropionate, lauryl stearyl 3, 3-thiodipropionate, pentaerythritol tetrakisto (j8-lauryl thiopropionate), 3 , 9 Bis (2 dodecylthioethyl) 2, 4, 8, 10-tetraoxaspiro [5, 5] undecane.

[0039] <Light stabilizer>

The light-resistant stabilizer used in the present invention will be described.

[0040] Examples of the light-resistant stabilizer include benzophenone-based light-resistant stabilizer, benzotriazole-based light-resistant stabilizer, hindered amine-based light-resistant stabilizer, and the like. In the present invention, from the viewpoint of transparency of the lens, resistance to coloring, etc. It is preferable to use a hindered amine light stabilizer. Among hindered amine light-resistant stabilizers (hereinafter referred to as HALS), a force S having a polystyrene equivalent Mn measured by GPC using tetrahydrofuran (THF) as a solvent is preferably 1,000 to 10,000 S, A force S of 2,000 to 5,000 is more preferable, and a force of 2,800 to 3,800 is particularly preferable. If Mn is too small, when HALS is blended by heating, melting and kneading into a block copolymer, it will not be able to blend a predetermined amount due to volatilization, or foaming or silver streak will occur during heat melting molding such as injection molding. This will reduce the stability of the cache. Also, when the lens is used for a long time with the lamp turned on, lens force volatile components are generated as gas. On the other hand, if Mn is too large, the dispersibility in the block copolymer is lowered, the transparency of the lens is lowered, and the effect of improving light resistance is reduced. Therefore, in the present invention, by setting HALS Mn in the above range, a lens having excellent processing stability, low gas generation and transparency can be obtained.

[0041] Specific examples of such HALS include N, Ν ', Ng, N'"— tetrakis [4,6-bis {petite (N-methyl-2,2,6,6-tetramethylpiperidine -4)) amino} —triazine—2-yl] —4, 7 diazadecane— 1,10 diamine, dibutylamine and 1, 3, 5 triazine and N, N '—bis (2, 2, 6, 6— Polycondensate with tetramethyl-4-piperidyl) butyramine, poly [{(1, 1, 3, 3-tetramethylbutyl) amino-1,3,5-triazine-1,2,4 dil} {(2, 2, 6, 6-tetramethyl-4-piperidyl) imino} hexamethylene {(2, 2, 6, 6-tetramethyl-1-piperidyl) imino}], 1, 6 hexanediamin-1 N, N '—bis (2 , 2, 6, 6-tetramethyl-4-piperidyl) and morpholine-1 2, 4, 6 Trichrome 1, 3, 5 Polycondensate with triazine, poly [(6 morpholinos s-triazine-2,4 diyl) (2, 2, 6, 6, —tetramethyl-4-piperidyl) imino ] -Hexamethylene [(2, 2, 6, 6-tetramethyl-4-piperidyl) imino] and other high molecular weight HALS with multiple piperidine rings linked via a triazine skeleton; cono, dimethyl succinate and 4-hydroxyl Polymer with 2, 2, 6, 6-tetramethyl-1-piperidineethanol, 1, 2, 3, 4 butanetetracarboxylic acid, 1, 2, 2, 6, 6 pentamethyl-4-piberidinol and 3,9bis (2 hydroxy 1,1,1-dimethylethyl) -1,2,4,8,10-tetraoxaspire High molecular weight HALS with piperidine ring bonded via ester bond, such as mixed esterified product with [5,5] undecane Etc.

[0042] Among these, polycondensates of dibutylamine, 1, 3, 5 triazine and N, N'-bis (2, 2, 6, 6-tetramethyl-4-piperidyl) ptyramine, poly [{(1, 1,3,3-Tetralametinolevbutenole) amino-1,3,5 triazine-2,4 dil} {(2, 2, 6, 6-tetramethyl-1-piperidyl) imino} hexamethylene {(2, 2 , 6, 6-tetramethyl-4-piperidyl) imino}], dimethyl succinate and 4-hydroxy 2, 2, 6, 6-tetramethyl-1-piperidineethanol, etc. , 000 is preferred.

[0043] The blending amount of the thermoplastic resin material of the present invention is preferably 0.01 to 20 parts by mass, more preferably 0.02 to 15 parts by mass, particularly preferably 100 parts by mass of the polymer. 0. 05 to 10 parts by mass. If the amount added is too small, the effect of improving light resistance cannot be obtained sufficiently, and coloring occurs when used outdoors for a long time. On the other hand, if the HALS content is too large, some of it will be generated as a gas, or the dispersibility in rosin will be reduced, and the transparency of the lens will be reduced.

[0044] Further, by blending the thermoplastic resin material of the present invention with a compound having the lowest glass transition temperature of 30 ° C or less, various properties such as transparency, heat resistance and mechanical strength can be obtained. Without lowering, it can prevent white turbidity in high temperature and high humidity environment for a long time.

The thermoplastic resin composition molded body of the present invention is obtained by molding a molding material comprising the resin composition. The molding method is not particularly limited, but melt molding is preferred in order to obtain a molded product excellent in characteristics such as low birefringence, mechanical strength, and dimensional accuracy. Examples of the melt molding method include commercially available press molding, commercially available extrusion molding, and commercially available injection molding, and injection molding is also preferable in terms of moldability and productivity.

[0046] The molding conditions are appropriately selected depending on the purpose of use or the molding method. For example, the temperature of the resin composition in injection molding may provide a suitable fluidity to the resin at the time of molding to reduce the sink of the molded product. From the viewpoint of preventing the occurrence of silver streaks due to thermal decomposition of the resin, and effectively preventing yellowing of the molded product, the range of 150 ° C to 400 ° C is preferable, and more preferably It is in the range of 200 ° C to 350 ° C, particularly preferably in the range of 200 ° C to 330 ° C.

[0047] Further, when molding a resin composition having a high aspect ratio and dispersed inorganic fine particles, it is necessary to select molding conditions that reduce the orientation of the inorganic fine particles in order to reduce the birefringence. is there.

[0048] The molded product according to the present invention can be used in various forms such as a spherical shape, a rod shape, a plate shape, a cylindrical shape, a tubular shape, a tubular shape, a fibrous shape, a film or a sheet shape, and has a low birefringence. Because of its excellent properties, transparency, mechanical strength, heat resistance, and low water absorption, it can be applied to various optical components. As specific application examples, for example, as an optical lens or an optical prism, a power imaging lens; a lens such as a microscope, an endoscope or a telescope lens; an all-light transmission lens such as a spectacle lens; CD, CD -ROM, WORM (recordable optical disc), MO (rewritable optical disc; magneto-optical disc), MD (mini disc), DVD (digital video disc) and other optical disc pickup lens; Laser scanning lens such as lens and sensor lens; prism lens of camera finder system.

[0049] Optical disc applications include CD, CD-ROM, WORM (recordable optical disc), MO (rewritable optical disc; magneto-optical disc), MD (mini disc), DVD (digital video disc), and the like. It is done. Other optical applications include light guide plates such as liquid crystal displays; optical films such as polarizing films, retardation films, and light diffusing films; light diffusing plates; optical cards; and liquid crystal display element substrates.

[0050] Among these, it is suitable as a pickup lens or a laser scanning system lens that requires low birefringence, and is most preferably used as a pickup lens. Example

[0051] Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited thereto.

[0052] Example 1

(Preparation of inorganic fine particles 1)

300 g of methanol and 1 mol% nitric acid aqueous solution were added to 5 g of vapor phase silica A300 (average particle size of about 7 nm) manufactured by Nippon Aerosil Co., Ltd. While stirring this solution at 50 ° C., a mixed solution of 100 g of methanol and 6 g of cyclopentyltrimethoxysilane was added over 60 minutes, and then the mixture was further stirred for 2 hours. The obtained transparent dispersion was suspended in ethyl acetate and centrifuged to obtain a white fine powder. According to TEM observation, this powder had an average particle size of about lOnm, and this was designated as inorganic fine particles 1.

[Preparation of inorganic fine particles 2]

A fine powder was obtained in the same manner as in the preparation of inorganic fine particles 1 except that Acid-Aluminum TM-300 (average particle size of about 7 nm) manufactured by Daimei Chemical Co., Ltd. was used. According to TEM observation, this powder had an average particle size of about lOnm, and this was designated as inorganic fine particles 2.

[Preparation of inorganic fine particles 3]

A fine powder was obtained in the same manner as the preparation of inorganic fine particles 1 except that aluminum nitride having an average particle diameter of about 5 nm obtained from Nanomat was used. According to TEM observation, this powder had an average particle size of about 8 nm, and this was designated as inorganic fine particles 3.

[Preparation of inorganic fine particles 4]

An aqueous zinc nitrate solution was added to the dispersion dispersed in water so that the concentration of Laponite XLG (Nippon Silica Kogyo, particle diameter 20-30 nm, thickness l-2 nm) was 0.5 wt%. An aqueous solution of thorium was added. Zinc nitrate and sodium sulfate were added so that the concentration in the final dispersion was 0.25 mM. Ultrafiltration was performed using USY-1 manufactured by Advantech Co., Ltd. to remove the clay, and it was dried to obtain fine zinc sulfate particles having an average particle size of 6 nm. 300 g of methanol and a 1 mol% nitric acid aqueous solution were added to 5 g of the obtained fine particles. While stirring this solution at 50 ° C., a mixed solution of methanol lOOg and cyclopentyltrimethoxysilane 6 g was added over 60 minutes, and then further stirred for 2 hours. The resulting transparent fraction The liquid dispersion was suspended in ethyl acetate and centrifuged to obtain a fine powder. According to TEM observation, this powder had an average particle size of about 9 nm, and this was designated as inorganic fine particles 4.

(Preparation of inorganic fine particles 5)

Fine powder was obtained in the same manner as the preparation of inorganic fine particles 1 except that Titanium ST-01 (average particle size: about 7 nm) manufactured by Ishihara Sangyo Co., Ltd. was used. According to TEM observation, this powder had an average particle size of about 8 nm and was designated as inorganic fine particles 5.

(Preparation of compacts 1-5)

A mixer: KF70 and a rotor: high shear type were mounted on a kneader Labo Plast Mill C type (manufactured by Toyo Seiki Seisakusho) and kneaded for 5 minutes at a preset temperature of 200 ° C and 300 rpm.

The kneading was performed by adding the following materials all at once to the mixer.

Oil: Zeonex 480R (made by Nippon Zeon) 37.5g,

Inorganic particles: Inorganic fine particles 1 to 5 18.5 g (15% w / w content)

The obtained kneaded material was injection-molded into a disk shape having a diameter of 10 mm and a thickness of 3 mm so that both surfaces of the disk were mirror surfaces. Let the obtained resin composition molded object be the molded object 1-5, respectively. (Production of molded body 6)

In the production method of the resin composition 1-5, the resin composition was added except that the added inorganic fine particles were inorganic fine particles 1,9.2 g (content in the resin 7.5% by weight). Let the molded product 6 be the resin composition molded product obtained by the same method as the production method of the molded products 1-5.

(Production of molded body 7)

Oil: Zeonex 480R (Nippon Zeon) 47. 6g,

Inorganic particles: Gas phase method silica A300 manufactured by Nippon Aerosil Co., Ltd. (average particle size of about 7 nm) 8.4 g (content ratio in wrinkle 15 w%)

The obtained kneaded material was injection-molded into a disk shape having a diameter of 10 mm and a thickness of 3 mm so that both surfaces of the disk were mirror surfaces. The obtained resin composition molded bodies are designated as molded bodies 7 respectively.

(Production of molded body 8) A molded body 8 was produced in the same manner as the molded body 7, except that the inorganic fine particles were changed to Daikin Chemical Industry Co., Ltd. Oxidium Aluminum TM-300 (average particle size: about 7 nm).

(Measurement of light transmittance)

Using a spectrophotometer UV-3150 manufactured by Shimadzu Corporation, the transmittance of the obtained resin composition molded product in the thickness direction (3 mm thickness) at a wavelength of 587.5 nm was measured.

(Measurement of linear expansion coefficient)

The linear expansion coefficient of the resin composition composition was measured by thermomechanical analysis (TMA) using CN8098F1 manufactured by Rigaku Corporation. The measurement was performed by measuring the displacement in the thickness direction of the disk.

(Measurement of dnZdT)

Each of the resin compositions used in the produced compacts 1 to 8 was melted and molded to prepare test plates having a thickness of 0.5 mm. With respect to these, the refractive index was measured using an Abbe refractometer (DR-M2 manufactured by Atago Co., Ltd.) at a wavelength of 588 nm and the measurement temperature was changed from 10 ° C. to 30 ° C., and the temperature change rate dnZdT of the refractive index was obtained.

[0057] Table 2 shows the results obtained as described above. The fine particle refractive index in the table is the refractive index at the d-line wavelength in the Balta state with the same composition as the fine particle, and is a literature value.

[0058] [Table 2]

[0059] As is apparent from the results shown in Table 2, the molded resin composition of the present invention has a low linear expansion coefficient and I dn / dT I and a high light transmittance. It turns out that it is very useful as a resin composition to be used.

[0060] Example 2

(Production of molded body 9) Mixer: KF70, Rotor: High shear type, kneading equipment lab plast mill type C (manufactured by Toyo Seiki Seisakusho), add the following ingredients to the mixer in a lump, and set at 200 ° C and 300 rpm for 5 minutes. Kneading was performed.

Oil: APL5014DP (Mitsui Engineering Co., Ltd.) 64.6g,

Inorganic particles: Nanofil919 (Scaly inorganic mineral montmorillonite surface modified with organic material) obtained from Sud Chemie Co. 3.4 g (5 wt% content in rosin) When the inorganic particles were observed by TEM, it was confirmed that they were dispersed in a layer shape having an average diameter of 200 nm and an average thickness of 1 nm. The obtained kneaded material was injection-molded into a disk shape having a diameter of 10 mm and a thickness of 3 mm so that both surfaces of the disk were mirror surfaces. The obtained resin composition molded product is referred to as molded product 9.

(Production of molded body 10)

A compact 10 was produced in the same manner as the compact 7, except that the inorganic particles were changed to NanoCeram (alumina nanofibers having a diameter of 2 nm and an aspect ratio of 20 to 100) obtained from Argonide. Observation of the inorganic particles in the obtained kneaded material by TEM confirmed that they were dispersed in a layer having an average diameter of 2 nm and an average length of 60 nm.

(Production of molded body 11)

Molded body 11 was produced in the same manner as molded body 9 except that the inorganic particles were changed to Nippon Aerosil Co., Ltd. and hydrophobic silica R974 (average primary particle size 12 nm). When the inorganic particles in the obtained kneaded material were observed with TEM, it was confirmed that the average dispersed particle size was 14 nm and dispersed in a lump.

(Production of molded body 12)

A molded body 12 was produced in the same manner as the molded body 9 except that the inorganic particles were changed to Nippon Steel Aerosil Co., Ltd. and acid aluminum C (average primary particle size 13 nm). When the inorganic particles in the obtained kneaded material were observed with TEM, it was confirmed that the average dispersed particle diameter was 16 nm and dispersed in a lump.

The obtained molded bodies 9 to 12 were measured for light transmittance, linear expansion coefficient, and I dn / dT I in the same manner as in Example 1.

Table 3 shows the results obtained as described above. [0062] [Table 3]

[0063] As is clear from the results shown in Table 3, the molded resin composition of the present invention has a low linear expansion coefficient and I dn / dT I and a high light transmittance. It turns out that it is very useful as a resin composition to be used.

Industrial applicability

[0064] According to the present invention, it is possible to provide a thermoplastic resin composition molded article which is excellent in transparency and has a small rate of change in size and refractive index due to temperature.

Claims

The scope of the claims

[1] A resin composition in which inorganic fine particles are dispersed in a resin matrix, wherein the refractive index of the inorganic fine particles is in the range of 1.3 to 2.3, and the optical path length of the resin composition and a light transmittance per 3mm 70% or more, and the linear expansion coefficient of ^{5 X 10 _5 (Z ° C} ) thermoplastic榭脂composition characterized by less.

[2] The resin composition according to claim 1, wherein the resin composition has a light transmittance of 85% or more per optical path length of 3 mm at a d-line wavelength.

[3] A resin composition in which inorganic fine particles are dispersed in a resin matrix, wherein the resin composition has a light transmittance of 70% or more at an optical path length of 3 mm at a d-line wavelength, A thermoplastic resin composition, wherein the fine particles are plate-like or needle-like.

[4] The inorganic fine particles are plate-like, and in the average size, the thickness is in the range of 0.1 to LOnm and the aspect ratio is 3 to LOOO. The coffin composition according to Item 3.

[5] The inorganic fine particles are needle-shaped, the average value of the shortest diameter of the inorganic fine particles is 0.1 to 10 nm, and the aspect ratio is in the range of 3 to 5000. The rosin composition as described in the item.

[6] The resin is at least one selected from acrylic resin, cyclic olefin resin, polycarbonate resin, polyester resin, polyether resin, polyamide resin and polyimide resin. The rosin composition according to claim 1.

[7] The resin according to claim 1, wherein the content of the inorganic fine particles is 0.01% by mass or more and 30% by mass or less with respect to the mass of the resin composition. Composition.

[8] An optical element characterized by being molded using the thermoplastic resin composition according to claim 1.

[9] The resin is at least one selected from acrylic resin, cyclic olefin resin, polycarbonate resin, polyester resin, polyether resin, polyamide resin and polyimide resin. The rosin composition according to claim 3.

[10] The resin according to claim 3, wherein the content of the inorganic fine particles is 0.01% by mass or more and 30% by mass or less with respect to the mass of the resin composition. Composition. An optical element formed by using the thermoplastic resin composition according to claim 3.