WO2011043187A1 - Eyeglasses molded article, process for production of same, and eyeglasses - Google Patents

Abstract

Disclosed are: an eyeglasses molded article mainly composed of a polylactic acid and having excellent heat resistance; a process for producing the eyeglasses molded article, which has excellent moldability; and an eyeglasses comprising the eyeglasses molded article. Specifically disclosed are: an eyeglasses molded article which comprises a stereocomplex polylactic acid resin composition containing 60 wt% or more of a stereocomplex polylactic acid (component A); a process for producing an eyeglasses molded article, which comprises melting and kneading a stereocomplex polylactic acid resin composition containing 60 wt% or more of a stereocomplex polylactic acid (component A), and injecting the molten resin under the conditions where the temperature of a mold is 80 to 130°C and the cooling time is 10 to 60 seconds; and an eyeglasses which comprises the eyeglasses molded article.

Description

Glasses molded body, manufacturing method thereof, and glasses

The present invention relates to a spectacle molded article composed of a stereocomplex polylactic acid resin composition, a method for producing the spectacle molded article, and spectacles having the spectacle molded article.

In recent years, bio-based polymers synthesized from plant-derived raw materials have attracted attention due to concerns about the depletion of petroleum resources and the problem of an increase in the amount of carbon dioxide in the atmosphere, which causes global warming. Such bio-based polymers have carbon neutral properties. That is, the polymer is finally decomposed into carbon dioxide by incineration or the like and released into the atmosphere, but since the plant as a raw material absorbs carbon dioxide in the atmosphere and synthesizes starch, as a whole, Does not increase the amount of carbon dioxide in the atmosphere.

Among bio-based polymers, polylactic acid, which is synthesized in large quantities and inexpensively from plant-derived raw materials such as corn, and has relatively high heat resistance and mechanical properties, has attracted attention.

Japanese Patent No. 3201739 discloses an eyeglass molded article composed of a polylactic acid-based biodegradable resin (Claim 1), and describes that poly-L-lactic acid is used as the polylactic acid-based resin. ([0013], Examples).

Japanese Patent No. 3201739

However, it is desired to further improve the heat resistance of the spectacle molded article obtained using the poly L-lactic acid as a material. For example, it is desired to solve problems such as glasses that are placed in a car in midsummer are deformed due to high temperatures in the car. Poly L-lactic acid is known to be inferior in moldability.

Therefore, an object of the present invention is to provide an eyeglass molded article having polylactic acid as a main component and excellent in heat resistance. Moreover, the objective of this invention is providing the manufacturing method of the said spectacles molded body excellent in the moldability. Furthermore, the objective of this invention is providing the spectacles which have the said spectacles molded object.

As a result of intensive studies to solve the above problems, the present inventors have obtained a glass molded article excellent in heat resistance with good moldability by using a resin composition containing stereocomplex polylactic acid as a main component. As a result, the present invention has been completed.

The present invention includes the following inventions.
(1) An eyeglass molded article composed of a stereocomplex polylactic acid-based resin composition containing 60% by weight or more of stereocomplex polylactic acid (component A).

(2) The above (1), wherein the stereocomplex polylactic acid resin composition contains 0.01 to 5 parts by weight of a crystal nucleating agent (component B) with respect to 100 parts by weight of stereocomplex polylactic acid (component A). The eyeglass molding described in 1.

(3) The above (1), wherein the stereocomplex polylactic acid resin composition comprises 0.01 to 5 parts by weight of a terminal blocking agent (component C) with respect to 100 parts by weight of stereocomplex polylactic acid (component A). Or the spectacles molding as described in (2).

(4) The above (1), wherein the stereocomplex polylactic acid resin composition contains 1 to 10 parts by weight of an impact modifier (D component) with respect to 100 parts by weight of stereocomplex polylactic acid (A component). The eyeglass molded article according to any one of (3) to (3).

(5) The stereocomplex polylactic acid resin composition comprises 45 parts by weight or less of polybutylene terephthalate resin (E component) with respect to 100 parts by weight of stereocomplex polylactic acid (A component). The spectacles molded product according to any one of (4).

(6) The eyeglass molded article according to any one of (1) to (5) above, wherein the stereocomplex polylactic acid resin composition has a melting point of 195 to 250 ° C.

(7) The above (1) to (6), wherein the spectacle molded body is at least one selected from the group consisting of a nose pad, a forehead, an ear modern, a Ude, and two or more of these integrally molded bodies. ).

(8) A stereocomplex polylactic acid resin composition containing 60% by weight or more of stereocomplex polylactic acid (component A) is melt-kneaded,
A method for producing a spectacle molded article, wherein a molten resin is injection-molded under conditions of a mold temperature of 80 to 130 ° C. and a cooling time of 10 to 60 seconds.

(9) The above (8), wherein the stereocomplex polylactic acid resin composition contains 0.01 to 5 parts by weight of a crystal nucleating agent (component B) with respect to 100 parts by weight of stereocomplex polylactic acid (component A). The manufacturing method as described in.

(10) The above (8), wherein the stereocomplex polylactic acid resin composition comprises 0.01 to 5 parts by weight of a terminal blocking agent (component C) with respect to 100 parts by weight of stereocomplex polylactic acid (component A). Or the manufacturing method as described in (9).

(11) The above (8), wherein the stereocomplex polylactic acid resin composition contains 1 to 10 parts by weight of an impact resistance improver (component D) with respect to 100 parts by weight of stereocomplex polylactic acid (component A). The production method according to any one of (10) to (10).

(12) The stereocomplex polylactic acid-based resin composition contains 45 parts by weight or less of polybutylene terephthalate resin (E component) with respect to 100 parts by weight of stereocomplex polylactic acid (component A). (11) The manufacturing method in any one of.

(13) The production method according to any one of (8) to (12) above, wherein the stereocomplex polylactic acid resin composition has a melting point of 195 to 250 ° C.

(14) The above-mentioned (8) to (13), wherein the spectacle molded body is at least one selected from the group consisting of a nose pad, a forehead, an ear modern, a Ude, and two or more of these integrally molded bodies. ).

(15) An eyeglass molded article according to any one of (1) to (7) above, or an eyeglass molded article obtained by the manufacturing method according to any of (8) to (14) above. Having glasses.

The eyeglass molded article of the present invention is preferable from the viewpoint of environmental protection because it mainly contains polylactic acid synthesized from plant-derived materials. Moreover, the eyeglass molded article of the present invention is excellent in heat resistance. Furthermore, according to the method for manufacturing a spectacle molded article of the present invention, a spectacle molded article can be obtained with good moldability.

It is a perspective view which shows one specific example of the spectacles which have the spectacles molded object of this invention.

(1): Nose pad
(2): forward
(3): Ude
(4): Ear modern
(10) (20): Glasses molding
(100): Glasses

The present invention will be described in detail below.
The eyeglass molded article of the present invention is a stereocomplex polylactic acid-based material containing 60% by weight or more, preferably 80% by weight or more, more preferably 90% by weight or more, and further preferably 95% by weight or more of stereocomplex polylactic acid (component A). It is comprised from a resin composition.

<Stereo complex polylactic acid (component A)>
Stereocomplex polylactic acid (component A) is a mixture of poly L-lactic acid and poly D-lactic acid.

Poly L-lactic acid is polylactic acid mainly composed of L-lactic acid units, and 90 to 100 mol% of L-lactic acid units, 0 to 10 mol% of D-lactic acid units and / or copolymerization components other than lactic acid, Consists of.

Poly-D-lactic acid is a polylactic acid mainly composed of D-lactic acid units, comprising 90 to 100 mol% of D-lactic acid units, 0 to 10 mol% of L-lactic acid units and / or copolymerization components other than lactic acid. Consists of.

Copolymerization components other than lactic acid are lactic acid monomers or other monomer components copolymerizable with lactide, and dicarboxylic acids, polyhydric alcohols, hydroxycarboxylic acids, lactones having two or more ester bond-forming functional groups. Etc .; and various polyesters, various polyethers, various polycarbonates and the like comprising these various components.

Examples of the dicarboxylic acid include succinic acid, adipic acid, azelaic acid, sebacic acid, terephthalic acid, and isophthalic acid.

Examples of polyhydric alcohols include aromatic polyhydric alcohols such as those obtained by addition reaction of bisphenol with ethylene oxide, ethylene glycol, propylene glycol, butanediol, hexanediol, octanediol, glycerin, sorbitan, trimethylolpropane, neopentyl glycol, etc. And aliphatic glycols such as diethylene glycol, triethylene glycol, polyethylene glycol, and polypropylene glycol.

Examples of the hydroxycarboxylic acid include glycolic acid and hydroxybutylcarboxylic acid.

Examples of the lactone include glycolide, ε-caprolactone glycolide, ε-caprolactone, β-propiolactone, δ-butyrolactone, β- or γ-butyrolactone, pivalolactone, δ-valerolactone, and the like.

Both poly L-lactic acid and poly D-lactic acid have a weight average molecular weight of 100,000 to 500,000, preferably 150,000 to 350,000. The weight average molecular weight is a standard polystyrene equivalent value measured by gel permeation chromatography (GPC) using chloroform as an eluent.

Poly L-lactic acid or poly D-lactic acid can be synthesized by a conventionally known method. That is, it can be synthesized by ring-opening polymerization of lactide (lactide method), dehydration condensation of lactic acid (direct polymerization method), a method combining these with solid phase polymerization, and the like. In the polymerization reaction, an organic tin compound such as tin octylate is usually used as a catalyst.

The weight ratio of poly L-lactic acid to poly D-lactic acid in stereocomplex polylactic acid (component A) is poly L-lactic acid / poly D-lactic acid = 90/10 to 10/90, and 75/25 to 25 / 75 is preferable, and 60/40 to 40/60 is more preferable. If the weight ratio of one polymer is less than 10 or exceeds 90, homocrystallization is prioritized and it is difficult to form a stereo complex, which is not preferable.

Stereocomplex polylactic acid (component A) can be produced by coexisting and mixing poly L-lactic acid and poly D-lactic acid at a predetermined weight ratio.

Mixing can be performed in the presence of a solvent. The solvent is not particularly limited as long as it dissolves poly L-lactic acid and poly D-lactic acid. For example, chloroform, methylene chloride, dichloroethane, tetrachloroethane, phenol, tetrahydrofuran, N-methylpyrrolidone, N, N-dimethylformamide, butyrolactone, trioxane, hexafluoroisopropanol and the like are preferably used alone or in combination of two or more.

Further, mixing can be performed in the absence of a solvent. That is, a method in which a predetermined amount of poly-L-lactic acid and poly-D-lactic acid are mixed and then melt-kneaded, or a method in which one of them is melted and the remaining one is added and kneaded can be employed.

The weight average molecular weight of stereocomplex polylactic acid (component A) is 100,000 to 500,000, preferably 100,000 to 300,000.

The melting point of stereocomplex polylactic acid (component A) obtained as described above is 195 to 250 ° C., preferably 200 to 220 ° C. Stereocomplex polylactic acid is excellent in crystallinity and heat resistance.

By using 60% by weight or more of such stereocomplex polylactic acid (component A) based on the whole composition, an eyeglass molded article having excellent heat resistance can be obtained with good moldability.

<Crystal nucleating agent (component B)>
The stereocomplex polylactic acid resin composition preferably contains a crystal nucleating agent (component B). The crystal nucleating agent (component B) is used for accelerating the crystallization of stereocomplex polylactic acid (component A) and maintaining the stereocomplex phase in the molded product composed of the resin composition in a stable and high level. Examples of the crystal nucleating agent (component B) include calcium silicate, talc, kaolinite, and montmorillonite. The crystal nucleating agent (component B) is preferably contained in an amount of 0.01 to 5 parts by weight, more preferably 0.1 to 3 parts by weight, based on 100 parts by weight of the stereocomplex polylactic acid (component A). More preferably, the content is ˜3 parts by weight.

<End-blocking agent (component C)>
The stereocomplex polylactic acid resin composition preferably contains a terminal blocking agent (C component). By using a terminal blocker (component C), the hydrolysis resistance of the spectacle molded article formed from the resin composition can be enhanced. The terminal blocking agent (component C) is preferably contained in an amount of 0.01 to 5 parts by weight, more preferably 1 to 3 parts by weight with respect to 100 parts by weight of the stereocomplex polylactic acid (component A).

The end-capping agent (C component) reacts with some or all of the carboxyl group ends of the polylactic acid (A component) in the resin composition and functions to block, for example, carbodiimide compounds, epoxy compounds, oxazolines. Compounds and the like.

As the carbodiimide compound, those synthesized by a known method can be used, and examples thereof include dicyclohexylcarbodiimide and diisopropylcarbodiimide.

Examples of epoxy compounds include ethylene oxide, propylene oxide, phenyl glycidyl ether, orthophenyl phenyl glycidyl ether, pt-butylphenyl glycidyl ether, N-glycidyl phthalimide, hydroquinone diglycidyl ether, resorcin diglycidyl ether, 1,6-hexane. Examples thereof include diol diglycidyl ether and hydrogenated bisphenol A-diglycidyl ether.

Examples of the oxazoline compound include 2,2′-m-phenylenebis (2-oxazoline), 2,2′-p-phenylenebis (2-oxazoline) and the like.

<Impact resistance improver (component D)>
The stereocomplex polylactic acid resin composition preferably contains an elastic polymer as an impact resistance improver (component D). By including an impact resistance improver (component D) in the resin composition, the impact resistance of the obtained spectacles can be improved. The impact resistance improver (component D) is preferably contained in an amount of 1 to 10 parts by weight, more preferably 2 to 8 parts by weight, based on 100 parts by weight of the stereocomplex polylactic acid (component A).

As an elastic polymer, a rubber component having a glass transition temperature of 10 ° C. or less, a monomer selected from aromatic vinyl, vinyl cyanide, (meth) acrylic acid ester, and a vinyl compound copolymerizable therewith Or the graft copolymer by which 2 or more types was copolymerized can be mentioned. The elastic polymer preferably contains 40% by weight or more of a rubber component, more preferably 60% by weight or more.

Examples of the rubber component include butadiene rubber, butadiene-acrylic composite rubber, acrylic rubber, and acrylic-silicone composite rubber.

Examples of the aromatic vinyl compound copolymerized with the rubber component include styrene, α-methylstyrene, p-methylstyrene, alkoxystyrene, halogenated styrene and the like, and styrene is particularly preferable.

Examples of the vinyl cyanide compound include acrylonitrile and methacrylonitrile.

Examples of the (meth) acrylic acid ester compound include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, octyl (meth) acrylate, cyclohexyl (meth) acrylate, and the like.
These can be used alone or in combination of two or more.

Such elastic polymers are commercially available and can be easily obtained. For example, as rubber components mainly composed of butadiene rubber, acrylic rubber, or butadiene-acrylic composite rubber, Kane Ace B series (for example, B-56 etc.) of Kaneka Chemical Industry Co., Ltd., Mitsubishi Rayon Co., Ltd. Metabrene C series (for example, C-223A), W series (for example, W-450A), Paraloid EXL series (for example, EXL-2602) by Kureha Chemical Co., Ltd., HIA series (for example, HIA- 15), BTA series (for example, BTA-III, etc.), KCA series, etc., and those containing acryl-silicone composite rubber as the main rubber component are METABRENE S-2001 or SRK from Mitsubishi Rayon Co., Ltd. Examples include those sold under the trade name of -200.

<Polybutylene terephthalate resin (component E)>
The stereocomplex polylactic acid resin composition preferably contains a polybutylene terephthalate resin (component E). Polybutylene terephthalate resin (E component) is excellent in moldability, mechanical strength, heat resistance and the like. By using the polybutylene terephthalate resin (E component), the moldability, mechanical strength, and heat resistance of the obtained spectacle molded article can be further improved. Polybutylene terephthalate resin (component E) can be used without any problem as long as the intrinsic viscosity is 0.5 to 2.0. The polybutylene terephthalate resin (component E) is preferably contained in 45 parts by weight or less, more preferably 20 parts by weight or more and 45 parts by weight or less, relative to 100 parts by weight of the stereocomplex polylactic acid (component A). More preferably, it is contained in an amount of 30 to 45 parts by weight.

<Various additives>
In the present invention, the stereocomplex polylactic acid-based resin composition may further include a plasticizer (such as phthalate ester), a stabilizer (such as calcium stearate), a color pigment (such as red lip yellow lead, titanium oxide), if necessary. Fillers (calcium carbonate, clay, talc, etc.), antioxidants (alkylphenols, organic phosphites, etc.), UV absorbers (salicylate, benzotriazole, etc.), flame retardants (phosphate esters, antimony oxide, etc.), Various conventionally known additives such as antistatic agents and antibacterial agents can be blended. These blending amounts can be determined as appropriate.

The stereocomplex polylactic acid-based resin composition constituting the spectacles molded article of the present invention comprises, as necessary, stereocomplex polylactic acid (component A), crystal nucleating agent (component B), terminal blocker (C Component), impact modifier (D component), polybutylene terephthalate resin (E component), and the above various additives are blended in the above blending ratio. The blending method is not particularly limited, and can be performed by a conventionally known method. For example, mixing and kneading may be performed using a mill roll, a Banbury mixer, a super mixer, a single screw or twin screw extruder, and the like.
Moreover, after mixing, it can be melt-kneaded and pelletized.

The melting point of the resin composition is 195 to 250 ° C., preferably 205 to 250 ° C.

The resin composition has a stereocomplex crystal content (X) represented by the following formula (I) using a melting enthalpy derived from stereocomplex polylactic acid (component A) in the temperature rising process of differential scanning calorimetry (DSC) measurement. ) Is 80% or more, preferably 85% or more, more preferably 90% or more.

X (%) = {ΔHb / (ΔHa + ΔHb) × 100 (I)

[In the formula (I), ΔHa and ΔHb are the melting enthalpy (ΔHa) of the crystal melting point appearing below 190 ° C. and 190 ° C. or above and below 250 ° C. in the temperature rising process of the differential scanning calorimeter (DSC), respectively. It is the melting enthalpy (ΔHb) of the crystalline melting point that appears. ]

The ΔHa and ΔHb are determined by measuring the resin composition using a differential scanning calorimeter (DSC) in a nitrogen atmosphere at a temperature increase rate of 20 ° C./min.
The higher the stereocomplex crystal content (X), the higher the hydrolysis resistance and heat resistance of the spectacle molded article obtained from the composition.

The resin composition obtained as described above is melt-kneaded and injection-molded under conditions of a mold temperature of 80 to 130 ° C. and a cooling time of 10 to 60 seconds, thereby forming a desired spectacle molded body shape. . The melting temperature of the resin composition is preferably not less than the melting point of the resin composition and in the range of 210 to 250 ° C.

Since the resin composition contains stereocomplex polylactic acid (component A) having excellent crystallinity, the cooling time during injection molding is as short as 10 to 60 seconds, and the moldability is excellent. For this reason, the production amount of the molded body per unit time is large, and the production efficiency is good.
In particular, a mold temperature of 80 to 115 ° C. and a cooling time of 10 to 50 seconds are preferable, and a mold temperature of 110 ° C. and a cooling time of 20 to 30 seconds are most preferable.
A molded body obtained by injection molding under the above conditions is excellent in surface scratch resistance.

Referring to FIG. 1, the eyeglass molded body may be a member for each member such as a nose pad (1), forehead (2), Ude (3), ear modern (4), etc. Of these, two or more integrally formed bodies may be used. As the two or more types of integral molded bodies, the nose pad and the front molded body (10); the ear modern and Ude integral molded body (20); The various things are mentioned.

As described above, the eyeglass molded article of the present invention may be colored to a desired color by blending a color pigment into the resin composition. In this invention, since stereocomplex polylactic acid (A component) excellent in crystallinity is used as a material, the obtained molded object is excellent in glossiness, and can be used as a member for spectacles without performing clear coating on the surface.
Moreover, the eyeglass molded article of the present invention may be one whose surface is coated with a paint or the like.

The eyeglasses having the eyeglass molded article of the present invention include sunglasses, sports sunglasses (various sports such as bicycle, land, ski, fishing), goggles and the like.

The eyeglasses of the present invention thus obtained have excellent heat resistance and do not deform due to heat even when placed at high temperatures. It also has excellent surface scratch resistance.

Hereinafter, although it demonstrates concretely using an Example, this invention is not limited to these Examples.

In Examples 1 to 3 below, stereocomplex polylactic acid (component A) (weight average molecular weight; 130,000) formed from equal weights of poly L-lactic acid and poly D-lactic acid was used.

[Example 1]
Stereocomplex polylactic acid (component A) 100 parts by weight, talc (component B) (Nippon Talc Co., Ltd .: P-3) 1 part by weight, epoxy-based endblocker (component C) (BASF Japan Co., Ltd.) 2 parts by weight of ADR-4368CS) was supplied to the raw material supply part of the twin-screw kneading extruder. The mixture was melt-extruded and pelletized at a cylinder temperature of 240 ° C., a screw rotation speed of 150 rpm, and a discharge rate of 25 kg / h. The obtained pellets had a melting point of 220 ° C.

The obtained pellets were melt-kneaded and injection-molded under the conditions of a mold temperature of 110 ° C. and a cooling time of 30 seconds, and the nose pad (1), the nose pad (1) and the front case (2 ) And the Ude (3) and the Ear Modern (4) integrally molded body (20), respectively.

[Example 2]
Stereocomplex polylactic acid (component A) 100 parts by weight, talc (component B) (Nippon Talc Co., Ltd .: P-3) 1 part by weight, epoxy-based endblocker (component C) (BASF Japan Co., Ltd.) 2 parts by weight of ADR-4368CS) and 5 parts by weight of acrylic rubber (component D) (Mitsubishi Rayon Co., Ltd .: Metabrene S-2001) were supplied to the raw material supply part of the twin-screw kneading extruder. Pelletization was performed under the same conditions. The obtained pellets had a melting point of 215 ° C.

The obtained pellets were melt-kneaded and injection molded under the same conditions as in Example 1 to obtain a nose pad (1), a spectacle molded body (10), and a spectacle molded body (20).

[Example 3]
Stereocomplex polylactic acid (component A) 100 parts by weight, talc (component B) (Nippon Talc Co., Ltd .: P-3) 1 part by weight, epoxy-based endblocker (component C) (BASF Japan Co., Ltd.) ADR-4368CS) 2 parts by weight, acrylic rubber (component D) (Mitsubishi Rayon Co., Ltd .: Methbrene S-2001), polybutylene terephthalate resin (E component) (Wintech Polymer Co., Ltd .: Jura) Nex 2002) 40 parts by weight was supplied to the raw material supply part of the twin-screw kneading extruder and pelletized under the same conditions as in Example 1. The obtained pellets had a melting point of 220 ° C.

The obtained pellets were melt-kneaded and injection molded under the same conditions as in Example 1 except that the cooling time was 20 seconds, and the nose pad (1), the spectacle molded body (10), and the spectacle molded body (20 )

[Comparative Example 1]
In the same manner as in Example 1, except that 100 parts by weight of poly L-lactic acid (manufactured by Nature Works: 4032B, weight average molecular weight 160,000, melting point 160 ° C.) was used instead of stereocomplex polylactic acid (component A). Pellets were obtained. The obtained pellets had a melting point of 170 ° C.

The obtained pellets were melt-kneaded and injection molded under the same conditions as in Example 1 except that the cooling time was 120 seconds, and the nose pad (1), the spectacle molded body (10), and the spectacle molded body ( 20) was obtained.

[Comparative Example 2]
Using the same material as in Comparative Example 1, pellets were obtained under the same conditions.
The obtained pellets were melt-kneaded and injection molded under the same conditions as in Comparative Example 1 except that the mold temperature was 40 ° C. and the cooling time was 30 seconds, and the nose pad (1) and the spectacle molded body (10) And the spectacles molding (20) was obtained.

The following characteristic evaluation was performed on the spectacle molded body (10) obtained by the above examples and comparative examples.

(Surface resistance)
The surface of the eyeglass molded article (10) shown in FIG. 1 was scratched with a nail, and the presence or absence of scratches was visually confirmed.
Judgment method Excellent: No visible scratches Inferior: Visually visible scratches

(Heat-resistant)
From the horizontal surface when the spectacles molded body (10) is fixed in a horizontal cantilever manner (so that the surface formed by the front frame (2) is substantially horizontal) and held at 90 ° C. for 30 minutes. A heat sag test (JIS K7195-1993) was conducted to determine the presence or absence of deformation (deflection). The presence or absence of deformation was confirmed visually.

The results are shown in Table 1.

As is clear from Table 1, all of the composition pellets obtained in Examples 1 to 3 had a higher melting point than Comparative Examples 1 and 2. Therefore, the eyeglass molded body (10) obtained in Examples 1 to 3 was not deformed in the heat sag test and was excellent in heat resistance. On the other hand, the molded body (10) obtained in Comparative Example 1 was deformed, and the molded body (10) obtained in Comparative Example 2 was further deformed more than the molded body of Comparative Example 1, All were inferior in heat resistance.

Further, in Examples 1 and 2 using stereocomplex polylactic acid (component A) having excellent crystallinity, crystallization progresses sufficiently in a short cooling time of 30 seconds at the time of injection molding, and a desired molded body (10) is obtained. Obtained. In Example 3, by using polylactic acid (component A) and polybutylene terephthalate resin (component E) in combination, the desired molded article (10) could be obtained in a shorter cooling time of 20 seconds. Thus, in Examples 1 to 3, it was possible to obtain the eyeglass molded article (10) with good molding processability. On the other hand, in Comparative Example 1 using poly L-lactic acid instead of stereocomplex polylactic acid (component A), when the mold temperature is 110 ° C., which is the same as the example, a desired molded body (10) is obtained. Therefore, a cooling time of 120 seconds was required. In Comparative Example 2, the mold temperature was lowered to 40 ° C. in order to set the cooling time to 30 seconds. However, the obtained molded article (10) had poor surface scratch resistance.

Claims (9)

An eyeglass molded article composed of a stereocomplex polylactic acid resin composition containing 60% by weight or more of stereocomplex polylactic acid (component A). The spectacles according to claim 1, wherein the stereocomplex polylactic acid resin composition contains 0.01 to 5 parts by weight of a crystal nucleating agent (component B) with respect to 100 parts by weight of stereocomplex polylactic acid (component A). Molded body. The eyeglasses according to claim 1, wherein the stereocomplex polylactic acid resin composition contains 0.01 to 5 parts by weight of a terminal blocking agent (component C) with respect to 100 parts by weight of stereocomplex polylactic acid (component A). Molded body. The spectacles according to claim 1, wherein the stereocomplex polylactic acid resin composition contains 1 to 10 parts by weight of an impact resistance improver (component D) with respect to 100 parts by weight of stereocomplex polylactic acid (component A). Molded body. The eyeglass molding according to claim 1, wherein the stereocomplex polylactic acid-based resin composition contains 45 parts by weight or less of polybutylene terephthalate resin (E component) with respect to 100 parts by weight of stereocomplex polylactic acid (A component). body. 2. The eyeglass molded article according to claim 1, wherein the stereocomplex polylactic acid resin composition has a melting point of 195 to 250 ° C. The spectacle molded body according to claim 1, wherein the spectacle molded body is at least one selected from the group consisting of a nose pad, a forehead, an ear modern, a Ude, and two or more of these integrally molded bodies. Melting and kneading a stereocomplex polylactic acid resin composition containing 60% by weight or more of stereocomplex polylactic acid (component A),
A method for producing a spectacle molded article, wherein a molten resin is injection-molded under conditions of a mold temperature of 80 to 130 ° C. and a cooling time of 10 to 60 seconds. An eyeglass molded article according to claim 1 or an eyeglass molded article obtained by the manufacturing method according to claim 8.

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