JPH0826214B2 - Polyester resin composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a thermoplastic polyester resin composition. More specifically, the present invention relates to a polyester resin composition having an excellent UV blocking property.

[Conventional technology]

Polyester typified by polyethylene terephthalate has been widely used for fibers, films and the like because of its excellent mechanical properties and chemical properties, but in recent years, due to its excellent transparency, gas barrier property, safety and hygiene, Carbonated drink,
The suitability as a container for fruit juice drink, liquid seasoning, edible oil, liquor or wine has been attracting attention. In addition, as a new application of the polyester film, a window pasting film for the purpose of shielding heat rays and preventing glass from scattering has recently been rapidly expanded from the viewpoint of energy saving and earthquake countermeasures.

[Problems to be solved by the invention]

However, although these polyester containers and films are excellent in ultraviolet ray blocking properties on the short wavelength side up to about 300 nm, they almost pass ultraviolet rays on the longer wavelength side, visible light, and the like. Such polyester containers are filled with liquid seasonings such as edible oil, mirin, and dressing, and when a storage period of several months elapses, depending on each filled food and storage conditions, special characteristics There is a gradual deterioration of the contents, for example,
Often causes subtle salinization in color, taste, and aroma. Degradation of the contents occurs due to external factors such as oxygen, heat, light, especially ultraviolet rays, and microorganisms. In the case of a polyester container, the oxygen shielding property is relatively excellent. It is possible to significantly prevent the deterioration of the contents even under storage.

In addition, with window sticking films, for example, if ultraviolet rays from the sun's rays are transmitted, it will cause discoloration of furniture, books, furniture and other indoor installation equipment, so the transmission will be minimized or blocked at all. There is a need.

At present, an ultraviolet absorber or the like is generally added and used for that purpose in the industry. However, these ultraviolet absorbers are generally expensive, and the applying step is complicated, and since these compounds generally have a large sublimation property and many have poor thermal stability, the applying step is difficult. Problems often occur during molding and molding. Further, when it is used for food containers or packaging, the added ultraviolet absorber may migrate to the contents, which is not always preferable.

[Means for solving problems]

As a result of intensive studies on polyester resin compositions that meet such purposes, the inventors of the present invention have shown that a polyester showing an excellent ultraviolet blocking effect without adding an ultraviolet absorber which is commonly used in the industry at present. They have found a resin composition and reached the present invention.

That is, the present invention is based on 100 parts by weight of the thermoplastic polyester resin, at least one or more of naphthalene dicarboxylic acid, its ester or imide, 0.001 parts by weight or more,
The present invention relates to a thermoplastic polyester composition having an excellent ultraviolet blocking property, which is added by 0 part by weight or less, preferably 5 parts by weight or less, more preferably 2 parts by weight or less. Hereinafter, the present invention will be described in detail.

In the present invention, naphthalenedicarboxylic acid, its ester, or imide is used as a raw material.

As naphthalenedicarboxylic acid, the following general formula (I)
For example, 2,6-, 2,7-, 2,3-, 1,8-, 1,7
Structural isomers such as-, 1,6-, 1,5-, 1,4-, 1,3-, and 1,2-naphthalenedicarboxylic acid may be mentioned.

(In the formula (I), R ¹ and R ² may be the same or different,
Hydrogen or an optionally substituted alkyl group, alkenyl group, aryl group, aralkyl group or alkylaralkyl group is shown.

In the formula (II), X is NR ³ and R ³ is an alkyl group or an aryl group substituted with a carboxyl group or a hydroxyl group. Moreover, -C (= O) -X-C (= O)-
The imide group of 1 forms a ring at any of the 1,2-position, 1,8-position or 2,3-position of the naphthalene ring. ) Preferred examples of naphthalenedicarboxylic acid esters include methyl, ethyl, propyl and butyl esters. Further, as the imide compound, a compound represented by the general formula (II)
Can be used as long as it is an imide of naphthalenedicarboxylic acid represented by, specifically, 1,8-naphthalenedicarboxylic acid-N- (α-carboxymethyl) imide,
(Β-carboxyethyl) imide,-(O- (m- or p-) carboxyphenyl) imide,-(α-hydroxymethyl) imide and the like can be mentioned.

The imides of these naphthalene dicarboxylic acids are, for example,
Naphthalene dicarboxylic acid or its derivative, glycine,
Produced by reaction with aliphatic aminocarboxylic acids such as alanine, valine, leucine and ε-aminocaproic acid, amino alcohols such as ethanolamine, and aromatic aminocarboxylic acids such as o-, m- or p-aminobenzoic acid. be able to.

The amount of such naphthalene dicarbomboic acid, its ester, or imide added is 0.001 part by weight or more and 10 parts by weight or less, preferably 5 parts by weight or less, and more preferably 2 parts by weight, per 100 parts by weight of the thermoplastic polyester resin. It is the following. When the amount added is less than 0.001 part by weight, a sufficient UV blocking effect cannot be obtained, and when the amount added exceeds 10 parts by weight, the original characteristics of the homopolyester are lost, which is not preferable.

Further, these compounds having a naphthalene dicarboxylic acid skeleton may be added at any stage during the production of polyester, and those added at any stage before the molding process similarly exhibit the ultraviolet blocking effect.

That is, it may be added at an arbitrary stage until the molding of the polyester is completed, for example, before the polycondensation reaction is started, during the polycondensation reaction, after the polycondensation reaction is completed, in a powder state, a molding stage, and the like.

The thermoplastic polyester in the present invention means an aromatic dicarboxylic acid such as terephthalic acid, isophthalic acid, phthalic acid, diphenyl ether dicarboxylic acid, diphenyl sulfone dicarboxylic acid or the like, an ester-forming product thereof, or the above aromatic aromatic compound such as hexahydroterephthalic acid. An alicyclic dicarboxylic acid which is a nuclear hydrogenated compound of dicarboxylic acid and an ester-forming product thereof,
One or more dicarboxylic acids selected from aliphatic dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, and azelaic acid and their ester-formers, unsaturated dicarboxylic acids such as fumaric acid and 4-carboxycinnamic acid, and their ester-formers A polyester obtained from an acid component and a glycol containing ethylene glycol as a main component, and particularly polyethylene terephthalate is mainly targeted. These polyesters may contain 20 mol% or less of the above dicarboxylic acids as a third component. good.

In addition, this polyester, as a glycol component,
Besides ethylene glycol, diethylene glycol, trimethylene glycol, tetramethylene glycol, neopentyl glycol and other aliphatic glycols, cyclohexanedimethanol and other alicyclic glycols, 2,2-bis-
(4'-β-hydroxyethoxyphenyl) propane,
Bisphenol derivatives such as bis- (4'-β-hydroxyethoxyphenyl) sulfone, and further, a general formula CH
_{2 n} O _m (where n is an integer of 1 ≦ n ≦ 6, m is m ≧
It may be a copolymer of polyethylene glycol, polytetramethylene glycol, etc. represented by the formula 4) up to 20 mol% of the total glycol component, or a polyester copolymerized with an oxyacid component such as hydroxybenzoic acid. May be. In addition, as long as the polyester is substantially linear, trifunctional or higher functional compounds such as pentaerythritol, trimethylolpropane, trimellitic acid, trimesic acid and pyromellitic acid, and monofunctional compounds such as O-benzoylbenzoic acid are used. It may be copolymerized. In addition to the above polyester, it may be a blend of other thermoplastic resins such as polybutylene terephthalate, polyethylene naphthalate, polyester elastomer, and polycarbonate.

The polyester used in the present invention preferably has an intrinsic viscosity of 0.5 or more, more preferably 0.6 or more. The viscosity of polyester is important particularly in relation to a molding method when, for example, a hollow molded body is produced. In particular, in order to obtain a substantially non-oriented hollow molded product by extrusion blow molding, it is necessary to maintain the fluidity of the molten polyester at a certain level or more in order to prevent drawdown, though it depends on the capacity of the blow molded product. Generally, a polyester having an intrinsic viscosity of 0.7 or more, preferably 0.8 or more is used. In addition, stretch blow molding, after sheeting, the extrusion molding method of uniaxially or biaxially stretching to obtain a film and the injection molding method of obtaining molded products of various forms have a relatively low viscosity compared to the case of the extrusion blow molding method. Polymers can also be used,
Generally, those having an intrinsic viscosity of 0.5 or more, preferably 0.6 or more are used, but depending on the required physical properties of the molded product, a polyester having a higher viscosity is also used.

In the present invention, additives conventionally known as a polyester resin composition, for example, stabilizers, release agents, antistatic agents, dispersants, and coloring agents such as dyes and pigments are added at any stage during polyester production. Or may be added by a so-called master batch processing method before molding.

The preferred dyes and pigments in the present invention include titanium oxide, carbon black, phthalocyanine blue, phthalocyanine green, ultramarine blue, gobart blue, titanium yellow, red iron oxide, burned amber, yellow oxide, and heat-resistant oil mainly composed of polycyclic ring. Soluble dyes, specifically, oil-soluble dyes having a skeleton of perinone type, quinophthalone type, anthrapyridone type, anthraquinone type, etc. can be mentioned, but they have a structure which reacts with a polyester functional group and bonds to a polyester chain. Are especially preferred.

Furthermore, dyes and pigments have good compatibility with polyester,
It is necessary to show sufficient heat resistance stability and color tone stability even at the production and processing temperatures of polyester, and in particular, when using a polyester resin molded product as a packaging container for foods, etc. Select the one that does not exist and add it.

The polyester resin composition of the present invention may be used as it is as a molded product, and, if necessary, further solid phase polymerization is performed under high vacuum or under inert gas flow to obtain a high degree of polymerization and a low aldehyde content. , Low oligomerization and molding,
It may be used after adding a post-treatment such as solvent extraction with xylene or chloroform.

In addition, a so-called master batch, which is colored to a desired color with a high density of several times to 100 times the predetermined density and practically up to about 50 times, is diluted with polyester which is uncolored or colored in another color tone. Alternatively, it is also possible to newly develop another color tone and finally obtain a desired color tone before subjecting it to the molding process.

The polyester resin composition excellent in ultraviolet blocking property obtained in the present invention is melt-molded to obtain a molded product, in which case all the melt-molding methods generally used in polyester resin molding can be applied. Is.

Specifically, for example, in order to obtain a hollow molded article, a usual extrusion blow method, an injection blow method, a blow molding method such as a cold parison method in which a pre-molded article is biaxially stretched after reheating is applied. Hollow molded body obtained by the molding method of, because it is excellent in ultraviolet blocking property, gas blocking property, toughness and chemical resistance, and has a high-grade glass-like transparency,
Seasonings such as soy sauce, sauce, mirin, dressing,
It is particularly suitable as a container for food such as edible oil, carbonated drink, fruit juice drink, liquor and wine, and a container for cosmetics, medicine and the like. Further, after being formed into a sheet by extrusion molding, a uniaxially or biaxially stretched film is used for packaging general foods and chemicals, cosmetics, etc., and further for window pasting, or as a mulching coating material used in agriculture and horticulture. Is also particularly preferably used, and preferable molded articles having various shapes can be obtained by other injection molding methods.

〔Example〕

Hereinafter, the present invention will be described in more detail with reference to Examples.
The present invention is not limited to the following examples unless it exceeds the gist.

In the examples, "parts" means "parts by weight", and various measuring methods used in this example are summarized below.

Intrinsic viscosity phenol-tetrachloroethane (50/50 weight ratio)
It was measured at 30 ° C. and a concentration of 1.0 g / dl.

Ultraviolet transmission was measured by a conventional method using a Hitachi spectrum photometer 340 type.

The amount of acetaldehyde was extracted with water at 160 ° C for 2 hours, and then quantified by high-sensitivity gas chromatography.

Inert gas flow rate The amount of gas flowing per unit time (hr) and per unit resin weight (kg) is shown as 1 atm and volume (1) converted to 25 ° C.

Example 1 Bis- (β-hydroxyethyl) terephthalate 20,0
To 00 parts, germanium dioxide 2 parts orthophosphoric acid 2 parts and 2,6
-Add naphthalene dicarboxylic acid 100, gradually increase the temperature from 260 ℃, and gradually reduce the pressure in the polymerization tank from atmospheric pressure to 28
A transparent polyester having an intrinsic viscosity of 0.60 was obtained at 0 ° C. and 1 torr with a total polymerization time of 2.5 hours.

After the polyester was dried in a usual vacuum, a sheet having a wall thickness of 350 μ was formed with a 30 mmφ extruder in which each part of the cylinder and the nozzle was 275 ° C., the screw rotation speed was 40 rpm, and the extrusion rate was 80 g / min.

The light transmittance of the sheet at 360 nm was 0.2%.

 The polyester chip is solid air (US Be
Crystallized in a stirring crystallization machine at a resin temperature of 150 ° C.
After that, it was transferred to a stationary solid-state polymerization tower, and nitrogen gas of 30 / kg
Solid-state polymerization was carried out at a resin temperature of 210 ° C. for 10 hours while flowing through the body.

The solid phase polymerized product had an intrinsic viscosity of 0.76 and contained 3.0 ppm of acetaldehyde in the chip material.

From this polyester, cylinder parts and nozzle
Injection molding machine IS-60 manufactured by Toshiba Corp. set to 275 ° C, screw rotation speed 100 rpm, injection time 10 seconds, mold cooling water temperature 10 ° C.
A preform was molded with B. This preform was blow-molded with a BMB-3 type machine manufactured by Corpoplast Co., Ltd., in which a preheating furnace was set to 90 ° C., a blow pressure was 20 kg / cm ² , and a molding cycle was 10 seconds to obtain a bottle having an internal volume of 1. The light transmittance of this 350 nm thick portion of the bottle body at 360 nm was 0.1%.

Example 2 Polymerization was conducted in the same manner as in Example 1 except that 60 parts of 2,3-naphthalenedicarboxylic acid-N- (α-carboxymethyl) imide was added instead of 2,6-naphthalenedicarboxylic acid, A transparent polyester having an intrinsic viscosity of 0.67 was obtained. Thickness obtained by molding from this polyester in the same manner as in Example 1 35
The light transmittance of the 0 μ sheet at 370 nm was 1.7%.

Example 3 Polymerization was carried out in the same manner as in Example 1 except that 1.4 parts of copper phthalocyanine and 2 parts of a quinophthalone-based reactive dye (manufactured by Mitsubishi Kasei Co., Ltd.) were added, and a green colored transparent with an intrinsic viscosity of 0.6 was obtained. I got polyester. A sheet having a thickness of 350 μ and molded from this polyester in the same manner as in Example 1 360
The light transmittance at nm was 0.2%.

The polyester chip was subjected to solid phase polymerization treatment and bottle molding in the same manner as in Example 1 to obtain a bottle having an inner volume of 1. The light transmittance at 350 nm of the 350 μ thick part of this bottle body is 0.1
It was in%.

Comparative Example 1 Bis- (β-hydroxyethyl) terephthalate 20,0
Only 2 parts of germanium dioxide and 2 parts of orthophosphoric acid were added to 00 parts, and polymerization was carried out under the same conditions as in Example 1 to obtain a polyester having an intrinsic viscosity of 0.68. A sheet having a thickness of 350 μm formed by using this polyester in the same manner as in Example 1 had a light transmittance of 65.5% at 360 nm and 67% at 370 nm.

〔The invention's effect〕

According to the present invention, it is possible to easily produce a thermoplastic polyester resin having an excellent ultraviolet blocking property on the long wavelength side without adding an ultraviolet absorber.

Claims (1)

[Claims] 1. At least one of naphthalene dicarboxylic acid and derivative represented by the following formulas (I) and (II) is added per 100 parts by weight of a thermoplastic polyester resin in an amount of 0.001 parts by weight or more and 10 parts by weight or less. A thermoplastic polyester resin composition comprising: (In the formula (I), R ¹ and R ² may be the same or different,
A hydrogen atom or an optionally substituted alkyl group, alkenyl group, aryl group, aralkyl group or alkylaralkyl group is shown. In the formula (II), X is NR ³ and R ³ is an alkyl group or an aryl group substituted with a carboxyl group or a hydroxyl group. The imide group of -C (= O) -X-C (= O)-forms a ring at any of the 1,2 position, 1,8 position and 2,3 position of the naphthalene ring. )