JP2013249392A - Refractive index modifier and use thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refractive index modifier, which can enhance a refractive index of a thermoplastic resin without deteriorating the transparency of the thermoplastic resin when mixed in the thermoplastic resin, and to provide a thermoplastic resin composition, in which the refractive index modifier is mixed, and a molded product of the resin composition.SOLUTION: A refractive index modifier comprises a dithiocarbonate compound represented by formula (I) as an ingredient. A (meth)acrylic resin composition or a polyester resin composition contains the refractive index modifier.

Description

  The present invention relates to a refractive index adjusting agent, a thermoplastic resin composition containing the same, and a molded product of the composition.

In recent years, research on optoelectronics toward an advanced information society has been vigorously conducted, and research on optical materials has been actively conducted to realize this. Optical materials that support various developments in optoelectronics, such as optical communication, optical recording, optical processing, optical measurement, and optical computation, have been developed.
For example, functional films using various plastic films such as anti-reflection (AR) film, anti-glare (AG) film, hard coat (HC) film, etc. are attached to the surface of the flat panel display. Helps prevent scratches on the surface. Important properties required for such plastic films include excellent transparency, high refractive index, excellent mechanical properties, and the like.

  In order to increase the refractive index of the resin, inorganic oxide fillers that do not absorb in the visible light wavelength band, for example, oxide fine particles such as zirconium oxide, tin oxide, indium oxide, titanium oxide, tantalum oxide, etc. It is known to do.

  Patent Document 1 proposes a composition of a metal oxide ultrafine particle and a polymer whose surface is modified with an acidic group or both an acidic group and a basic group. However, the metal oxide ultrafine particles coated with acetic acid and hexylamine, which are specifically described, have poor compatibility with (meth) acrylate resins, and therefore provide a high refractive index while maintaining transparency. It was difficult.

  Patent Document 2 proposes a transparent composite in which nanometer-grade zirconia particles are dispersed in a resin. However, the zirconia particles dispersed in the resin have a very large specific surface area, and the surface of the zirconia particles is strongly acidic and has a high oxidizing ability, so that depending on conditions. There was a possibility that the resin was discolored during use.

  On the other hand, Patent Document 3 describes an invention relating to a method for producing a 1,3-oxathiolane-2-thione derivative that is a dithiocarbonate compound according to the present invention. This document discloses that 1,3-oxathiolane-2-thione derivatives are used in the field of paints and inks as photosensitive resins and polymer crosslinking agents (see paragraph 0002). No mention is made of the refractive index of the resin.

Patent Document 4 describes an invention related to a thiocarbonate polymer, and this thiocarbonate polymer is excellent in heat resistance, chemical resistance, weather resistance, mechanical strength and adhesion to metal, and has a high refractive index. (See paragraph 0001).
In addition, since polymers containing sulfur atoms are expected to have a high refractive index due to the large atomic refraction of sulfur atoms, they can be used as resins for optical materials used in high refractive index organic glasses, lenses, optical elements, etc. Is expected to be used (see paragraph 0002).
The thiocarbonate polymer of the invention described in this document is said to be a ring-opening polymer of a heterocyclic compound obtained by reaction of carbon disulfide with bisphenol F diglycidyl ether or bisphenol A diglycidyl ether. (See paragraphs 0032-0035).

Patent Document 5 describes an invention related to polythiourethane, which is said to be excellent in mechanical properties such as strength and optical properties such as refractive index (paragraph 0008). reference).
Polythiourethane is used as a raw material for high refractive index optical materials (JP-A-5-208950, JP-A-5-202347), adhesives for optical materials (JP-A-3-56525), and the like. It is believed to be a useful compound (see paragraph 0002).
In addition, the point obtained by reaction of the dithiocarbonate compound which concerns on this invention and the diamine compound is disclosed for the polythiourethane of the invention described in this literature (for example, refer Example 1).

JP 2003-73558 A JP 2007-99931 A JP-A-5-247027 Japanese Patent Laid-Open No. 11-292969 JP-A-8-302012

An object of this invention is to provide the refractive index regulator which can raise a refractive index, without impairing the transparency of a thermoplastic resin, when mix | blending with a thermoplastic resin.
Moreover, it aims at providing the thermoplastic resin composition which mix | blended this refractive index regulator, and the molding of this resin composition.

As a result of intensive studies to solve the above problems, the present inventors have achieved the intended purpose by using the dithiocarbonate compound represented by the chemical formula (I) of Chemical Formula 1 as a refractive index adjusting agent. As a result, the present invention has been completed.
That is, the first invention is a refractive index adjusting agent characterized by comprising a dithiocarbonate compound represented by the chemical formula (I) as a component.
2nd invention mix | blended 5-50 weight part of refractive index regulator as described in 1st invention with respect to 100 weight part of (meth) acrylic resin or polyester resin, The thermoplastic resin composition characterized by the above-mentioned. It is.
3rd invention is a molding of the thermoplastic resin composition as described in 2nd invention.

（式中、Ｒは、水素原子またはメチル基を表わす。ｎは、０〜５の整数を表わす。）

(In the formula, R represents a hydrogen atom or a methyl group. N represents an integer of 0 to 5.)

  The molded product of the thermoplastic resin composition containing the refractive index adjusting agent of the present invention has high transparency and high refractive index.

Hereinafter, the present invention will be described in detail.
The dithiocarbonate compound which is a component of the refractive index adjusting agent of the present invention is represented by the above chemical formula (I).

As the compound, for example,
Bisphenol F dithiocarbonate methyl ether,
Mention may be made of bisphenol A dithiocarbonate methyl ether. In addition, you may use combining these dithiocarbonate compounds as a component of a refractive index regulator.

Such a dithiocarbonate compound can be synthesized according to the methods described in Patent Document 3 and Patent Document 5 described above.
For example, it can be easily synthesized by reacting carbon disulfide and a bifunctional epoxy compound in an aprotic solvent in the presence of a suitable catalyst such as an alkali metal salt or an alkaline earth metal salt. it can. As the bifunctional epoxy compound, it is preferable to use a bisphenol A type epoxy compound or a bisphenol F type epoxy compound.

The thermoplastic resin composition of the present invention can be obtained by blending the refractive index adjusting agent described above with a thermoplastic resin. A (meth) acrylic resin or a polyester resin is used as the thermoplastic resin.
In preparing the thermoplastic resin composition of the present invention, the refractive index adjuster of the present invention is preferably blended at a ratio of 5 to 50 parts by weight with respect to 100 parts by weight of the thermoplastic resin. More preferably, it is blended at a ratio of parts.
If the blending ratio of the refractive index adjusting agent is less than 5 parts by weight, the refractive index of the molded product of the thermoplastic resin composition of the present invention cannot be made sufficiently large. The mechanical properties of

  The thermoplastic resin composition of the present invention can be obtained by mixing the refractive index adjusting agent of the present invention and a thermoplastic resin by a method such as continuous extrusion kneading.

  The molded article of the thermoplastic resin composition of the present invention has excellent permeability and molding processability, high refractive index, and can be adjusted arbitrarily, so that it is suitable as a raw material for optical components. .

  The thermoplastic resin composition of the present invention can be softened by heating and processed into a molded product by molding or extrusion in the softened state. For example, a film having a thickness of about 0.1 to 5000 μm can be obtained by pressing in a heated state.

  Moreover, the thermoplastic resin composition of the present invention can be melt-molded, and can be extrusion molding, injection molding, vacuum molding, blow molding, compression molding, blow molding, calendar molding, laminate molding, and the like. Thereby, various optical components, such as a disk and a fiber, can be obtained.

The optical component obtained by molding the thermoplastic resin composition of the present invention is suitable for, for example, applications requiring high refractive index and transparency, or applications requiring both high refractive index and transparency. It is a thing.
Also, since the refractive index can be adjusted arbitrarily, it can be suitably used for optical components in which different refractive indexes are distributed continuously or discontinuously, such as optical fibers, optical waveguides and some lenses. it can.
Specific examples of such optical components include lenses (for example, eyeglass lenses, optical equipment lenses, optoelectronic lenses, laser lenses, CD pickup lenses, automotive lamp lenses, OHP lenses, etc.), optical fibers, Examples include an optical waveguide, an optical filter, an optical adhesive, an optical disk substrate, a display substrate, a coating material, and a prism.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention in detail, this invention is not limited to these. In addition, the thermoplastic resin used for these is as follows.

[Thermoplastic resin]
・ (Meth) acrylic resin: Polymethylmethacrylate resin (abbreviated as “PMMA”, manufactured by Kuraray Co., Ltd., trade name “PARAPET GF”)
Polyester resin: Polyethylene terephthalate resin (abbreviated as “PET”; manufactured by Teijin Chemicals, trade name “TRN-8550FF”)

In Examples and Comparative Examples, dithiocarbonate compounds and inorganic oxide fillers used as refractive index adjusters are as follows.
Reference examples 1 and 2 show synthesis examples of the former dithiocarbonate compound.

[Refractive index modifier]
Bisphenol F dithiocarbonate methyl ether (abbreviated as “BFTC”)
Bisphenol A dithiocarbonate methyl ether (abbreviated as “BATC”)
・ Zirconia (manufactured by TECNAN, trade name “TECNAPOW-ZRO2”, average particle diameter of 15 nm)
・ Zinc oxide (manufactured by Sakai Chemical Co., Ltd., trade name “FINEX.50S-LP2”, average particle size 20 nm)

[Reference Example 1]
<Synthesis of BFTC>
Bisphenol F diglycidyl ether (332 g, 1.0 mol), lithium bromide (0.5 g) and tetrahydrofuran (500 mL) were charged into a flask equipped with a reflux condenser to prepare a reaction solution.
While stirring this reaction solution, 182 g (2.4 mol) of carbon disulfide was added dropwise, and subsequently stirred at room temperature for 12 hours, and then concentrated under reduced pressure. The concentrate was diluted with 800 mL of dichloroethane, added with 400 mL of water, stirred and shaken, allowed to stand, and separated into an aqueous layer and a dichloroethane layer.
Next, the dichloroethane layer was concentrated and dried under reduced pressure to obtain 412 g (yield: 88.7%) of BFTC represented by the chemical formula (II) of Chemical Formula 2.

[Reference Example 2]
<Synthesis of BATC>
Bisphenol A diglycidyl ether 340 g (1.0 mol), lithium bromide 0.5 g, and dioxane 500 mL were charged into a flask equipped with a reflux condenser to prepare a reaction solution.
While stirring this reaction solution, 182 g (2.4 mol) of carbon disulfide was added dropwise, and subsequently stirred at room temperature for 8 hours, and then concentrated under reduced pressure. After adding 800 mL of methanol to the concentrate, the precipitate was collected by filtration, washed with water, and dried under reduced pressure to obtain 455 g (92.5%) of BATC represented by Chemical Formula (III) of Chemical Formula 3.

  The evaluation tests conducted in the control test, the examples and the comparative examples are as follows.

[Measurement of transmittance]
Based on ASTM D1003, the transmittance | permeability of the visible light of the wavelength range of 350-800 nm was measured using the spectrophotometer (JASCO Corporation V-570). The transmittance value is shown as a relative value when air is 100%.

[Measurement of refractive index]
In accordance with JIS K 7142 “Plastic Refractive Index Measuring Method”, an Abbe refractometer (DR-M4 type, manufactured by Atago Co., Ltd.) was used to measure the refractive index of light having a wavelength of 589 nm.

[Control study 1]
Using a single screw extruder, PMMA was continuously kneaded at a cylinder temperature of 210 ° C. flat to prepare pellets. This was injection-molded to produce a plate-shaped test piece having a thickness of 0.5 mm, and the transmittance and refractive index of the test piece were measured.
The obtained measurement data was as shown in Table 1.

[Examples 1-2, Comparative Examples 1-2]
A pellet of a thermoplastic resin composition having the composition described in Table 1 was prepared in the same manner as in Control Test 1 except that a refractive index modifier was blended with PMMA, and then a plate-shaped test piece was prepared. The transmittance and refractive index of this test piece were measured.
The obtained measurement data was as shown in Table 1.

[Control study 2]
Pellets were prepared and specimens were prepared in the same manner as in Control Test 1, except that PET was used instead of PMMA and the cylinder temperature of the single screw extruder was flat at 260 ° C. And the refractive index was measured.
The obtained measurement data was as shown in Table 1.

[Example 3, Comparative Example 3]
Except that the refractive index adjuster was used, a pellet of a thermoplastic resin composition having the composition described in Table 1 was prepared in the same manner as in Control Test 2, and then a plate-shaped test piece was prepared. The transmittance and refractive index of the test piece were measured.
The obtained measurement data was as shown in Table 1.

  According to the test results shown in Table 1, the molded product of the thermoplastic resin composition of polymethyl methacrylate resin and polyethylene terephthalate resin blended with the refractive index modifier of the present invention was blended with the refractive index modifier of the prior art. Compared to the case, it is recognized that the transmittance and the refractive index are increased.

  According to the present invention, since the refractive index of a (meth) acrylic resin and polyester resin molded product can be increased and transparency can be maintained, not only optical lenses and functional optical films but also optical fields can be introduced. Application of the present invention to an optical plate, a diffusion film, a holographic substrate, a light control film and the like can be expected.

Claims (3)

A refractive index adjusting agent comprising a dithiocarbonate compound represented by chemical formula (I) of Chemical Formula 1 as a component.

(In the formula, R represents a hydrogen atom or a methyl group. N represents an integer of 0 to 5.)   A thermoplastic resin composition comprising 5 to 50 parts by weight of the refractive index adjusting agent according to claim 1 in 100 parts by weight of a (meth) acrylic resin or a polyester resin.   A molded article of the thermoplastic resin composition according to claim 2.