JPH04361027A - Piece for forming bottle mouth plug part, bottle made of saturated polyester having said piece and proparation thereof - Google Patents

Abstract

PURPOSE:To provide a piece for forming a bottle mouth plug part excellent in heat resistance, dimensional stability and mechanical strength and a bottle made of saturated polyester having said bottle mouth plug part. CONSTITUTION:A piece for forming a bottle mouth plug part is composed of a polyester composition containing polyethylene terephthalate (i), polybutylene terephthalate (ii) and talc and/or titanium dioxide (iii). A bottle made of polyester consisting of a mouth plug part and a body part is composed of said polyester composition and the body part thereof is composed of stretched saturated polyester.

Description

[Detailed description of the invention]

0001

TECHNICAL FIELD OF THE INVENTION The present invention relates to a piece for forming a bottle cap, a saturated polyester bottle having the piece, and a method for manufacturing the same, and more particularly to a bottle cap with excellent heat resistance, dimensional stability, and mechanical strength. The present invention relates to a saturated polyester bottle having a spout having excellent heat resistance, dimensional stability, and mechanical strength, as well as a method for producing the same.

0002

TECHNICAL BACKGROUND OF THE INVENTION In recent years, various plastics have been used as materials for bottles for soft drinks such as juices and sports drinks, and carbonated drinks such as cola. Among them, saturated polyesters such as polyethylene terephthalate (PET) are often used as materials for bottles because of their excellent transparency, gas barrier properties, heat resistance, and mechanical strength.

[0003] Juices and the like are usually filled at high temperatures, and therefore there is a demand for bottles to be made of heat-resistant resin that can withstand high-temperature filling. Bottles made of saturated polyester, such as PET bottles, usually consist of a spout and a body, and the body is stretch-molded and has molecular orientation, which gives it excellent heat resistance and mechanical strength. ing. On the other hand, since the plug part is hardly stretched, it has poor heat resistance and has the problem of being deformed during high-temperature filling.

In order to solve this problem, for example, Japanese Patent Application Laid-open No. 59-33101 describes crystallizing the neck of a saturated polyester bottle by heat treatment. In this method, the crystallization step is a separate step, so
A crystallization device is required to crystallize the neck, and time is required for crystallization, which lengthens the molding cycle.Furthermore, the degree of crystallinity tends to vary, and the dimensional accuracy of the neck is poor. Was.

[0005] Furthermore, JP-A-2-208924 describes a method for obtaining a highly heat-resistant mouth part by multilayer molding of saturated polyester and polycarbonate, which is a resin with a high glass transition point.

[0006]

[Object of the Invention] The present invention aims to solve the problems in the prior art, and provides a piece for forming a bottle spout that has excellent heat resistance, dimensional stability, and mechanical strength. The object of the present invention is to provide a saturated polyester bottle having the above-mentioned piece having excellent heat resistance, dimensional stability, and mechanical strength, and a method for manufacturing the same.

[0007]

SUMMARY OF THE INVENTION A piece for forming a bottle cap according to the present invention is made of a polyester composition containing (i) polyethylene terephthalate, (ii) polybutylene terephthalate, and (iii) talc and/or titanium dioxide. It is characterized by

[0008] The saturated polyester bottle according to the present invention is a polyester bottle comprising a spout and a body, the spout comprising (i) polyethylene terephthalate;
It is characterized in that it is made of a polyester composition containing (ii) polybutylene terephthalate and (iii) talc and/or titanium dioxide, and the body is made of stretched saturated polyester.

[0009] Furthermore, the method for producing a saturated polyester bottle according to the present invention includes (i) polyethylene terephthalate, (ii) polybutylene terephthalate, and (iii)
) A polyester composition containing talc and/or titanium dioxide is injected into a mold to form a piece for forming a bottle spout, and then a saturated polyester composition is injected into the mold into which the piece for forming a bottle spout is inserted. is injected to form a preform body to form a preform, and the obtained preform is stretch blow molded.

0010

DETAILED DESCRIPTION OF THE INVENTION Hereinafter, a piece for forming a bottle cap, a saturated polyester bottle having the piece, and a method for manufacturing the same according to the present invention will be described.

The bottle cap forming piece according to the present invention comprises (i) polyethylene terephthalate, (ii) polybutylene terephthalate, (iii) talc and/or
Alternatively, it is made of a polyester composition containing titanium dioxide.

Such a polyester composition for forming a piece contains (i) 20 to 80 parts by weight, preferably 30 to 70 parts by weight, more preferably 4 parts by weight of polyethylene terephthalate.
(ii) 10 to 60 parts by weight of polybutylene terephthalate, preferably 15 to 50 parts by weight, more preferably 20 to 40 parts by weight, and (iii) 5 parts by weight of talc.
~50 parts by weight, preferably 10-40 parts by weight, more preferably 15-30 parts by weight and/or 0 parts by weight of titanium dioxide
．． It is desirable to contain 5 to 30 parts by weight, preferably 1 to 25 parts by weight, and preferably 2 to 20 parts by weight.

[0013] The intrinsic viscosity [η] of the polyester composition for forming a piece is 0.4 to 1.5 dl/g, preferably 0.5
It is desirable that it be ~1.2 dl/g. In addition, the heat distortion temperature (HDT) is 85 to 200°C, preferably 90 to 1
The temperature is preferably 50°C.

[0014] In order to manufacture the piece for forming a bottle cap according to the present invention, (i) polyethylene terephthalate;
A piece-forming polyester composition comprising (ii) polybutylene terephthalate and (iii) talc and/or titanium dioxide is injected into a mold. On this occasion,
The temperature of the mold is usually 50-150°C, preferably 70-150°C.
The temperature is preferably 40°C.

[0015] The crystallinity of the piece for forming a bottle spout made of such a polyester composition for forming a piece is 5%.
Above, preferably 10% or more. The bottle cap forming piece according to the present invention is made of a polyester composition containing (i) polyethylene terephthalate, (ii) polybutylene terephthalate, and (iii) talc and/or titanium dioxide, so it has high heat resistance, It has excellent mechanical strength and dimensional accuracy, and has excellent mold release properties during molding. Furthermore, since the bottle cap according to the present invention contains talc and/or titanium dioxide, it becomes opaque white and has a desirable appearance when used as a transparent bottle cap.

[0016] Below, polyethylene terephthalate, polybutylene terephthalate, talc,
Titanium dioxide will be specifically explained. [Polyethylene terephthalate] The polyethylene terephthalate resin used in the present invention is formed from a dicarboxylic acid constituent unit containing a terephthalic acid constituent unit and a dihydroxy constituent unit containing an ethylene glycol constituent unit.

This polyethylene terephthalate contains 20
Up to mol % of other dicarboxylic acids and/or other dihydroxy compounds other than terephthalic acid and ethylene glycol may be copolymerized. Specifically, dicarboxylic acids used in copolymerization other than terephthalic acid include:
Aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenoxyethanedicarboxylic acid; Aliphatic dicarboxylic acids such as adipic acid, sebacic acid, azelaic acid, decanedicarboxylic acid; cyclohexanedicarboxylic acid, cyclohexanedicarboxylic acid, etc. Examples include alicyclic dicarboxylic acids such as propanedicarboxylic acid and hexahydroterephthalic acid.

In addition to ethylene glycol, dihydroxy compounds used in copolymerization include aliphatic glycols such as trimethylene glycol, propylene glycol, tetramethylene glycol, neopentyl glycol, hexamethylene glycol, and dodecamethylene glycol; cyclohexane; Alicyclic glycols such as dimethanol; bisphenols; hydroquinone, 2,
Examples include aromatic diols such as 2-bis(4-β-hydroxyethoxyphenyl)propane.

The polyethylene terephthalate used in the present invention also contains a small amount, for example, 2 mol % or less, of a structural unit derived from a polyfunctional compound such as trimesic acid, trimethylolethane, trimethylolpropane, trimethylolmethane, or pentaerythritol. may be included.

Furthermore, the polyethylene terephthalate used in the present invention contains a small amount, for example, 2 mol % or less, of a constituent unit derived from a monofunctional compound such as benzoylbenzoic acid, diphenylsulfone monocarboxylic acid, stearic acid, methoxypolyethylene glycol, or phenoxypolyethylene glycol. It may be included in an amount of

[0021] Such polyethylene terephthalate forms a substantially linear polyester by ethylene terephthalate component units alone or by randomly arranging the ethylene terephthalate component units and dioxyethylene terephthalate component units to form ester bonds. are doing. The fact that the polyethylene terephthalate is substantially linear is confirmed by dissolving the polyethylene terephthalate in o-chlorophenol.

[0022] Such polyethylene terephthalate has an intrinsic viscosity [η] (value measured in o-chlorophenol at 25°C) of usually 0.4 to 1.5 dl/g, preferably 0.5 to 1.2 dl. /g is desirable. In addition, the melting point is usually 210°C to 265°C, preferably 220°C.
It is desirable that the temperature is ~260°C, and the glass transition temperature is
It is desirable that the temperature is usually 50 to 90°C, preferably 60 to 90°C.

[Polybutylene terephthalate] The polybutylene terephthalate used in the present invention is formed from a dicarboxylic acid constituent unit containing a terephthalic acid constituent unit and a dihydroxy compound constituent unit containing a 1,4-butanediol constituent unit.

In the polybutylene terephthalate according to the present invention, in addition to the above-mentioned terephthalic acid as a dicarboxylic acid component, other dicarboxylic acids are added in an amount that does not impair the properties of the resulting polybutylene terephthalate, for example, 20 mol% or less. It can also be used.

Examples of such dicarboxylic acids include isophthalic acid, phthalic acid, 2-methylterephthalic acid, 2,6-
Examples include naphthalene dicarboxylic acid. In addition, in the polybutylene terephthalate according to the present invention, other dihydroxy compounds other than 1,4-butanediol may be used in an amount that does not impair the properties of the resulting polybutylene terephthalate, for example, 20 mol% or less. You can also do it.

[0026] Such dihydroxy compounds include:
1,3-propanediol, neopentyl glycol,
Cyclohexanediol, cyclohexanedimethanol, 1,3-bis(2-hydroxyethoxy)benzene,
1,4-bis(2-hydroxyethoxy)benzene, 2
, 2-bis(4-β-hydroxyethoxyphenyl)propane, bis(4-β-hydroxyethoxyphenyl)
Dihydroxy compounds having 3 to 15 carbon atoms such as sulfone can be mentioned.

[0027] Such polybutylene terephthalate has an intrinsic viscosity [η] (measured in o-chlorophenol at 25°C) of 0.4 to 2.0 dl/g, preferably 0.
．． It is desirable that it is 5 to 1.5 dl/g. Further, it is desirable that the melting point is 200 to 255°C, preferably 220 to 250°C, and the glass transition temperature is 40 to 70°C.
, preferably 45 to 60°C.

[Talc] The talc used in the present invention is
Average particle size is 0.01 to 20 μm, preferably 0.1 to 20 μm
5 μm and a specific surface area of 0.1 to 50 m 2 /g, preferably 1 to 10 m 2 /g.

[Titanium Dioxide] It is desirable that the titanium dioxide used in the present invention has an average particle diameter of 0.01 to 10 μm, preferably 0.1 to 5 μm.

The piece-forming polyester composition containing the above components also contains a crosslinking agent, a heat stabilizer, a weather stabilizer,
Antistatic agents, lubricants, mold release agents, inorganic fillers, pigment dispersants,
Various compounding agents such as pigments and dyes may be contained within the range that does not impair the object of the present invention.

Next, the saturated polyester bottle according to the present invention will be specifically explained. FIG. 1 shows a schematic diagram of a saturated polyester bottle according to the present invention. A saturated polyester bottle 1 according to the present invention consists of a spout 2 and a body 3, as shown in FIG.

The spout portion 2 is made of (i) polyethylene terephthalate, (ii) polybutylene terephthalate, and (
iii) A piece-forming polyester composition containing talc and/or titanium dioxide.

The degree of crystallinity of the spout 2 made of the piece-forming polyester composition is desirably 5% or more, preferably 10% or more. The body part 3 is formed from polyester for forming the body part that has been uniaxially or biaxially stretched, preferably biaxially stretched, and may be heat set during molding. Examples of the polyester for forming the body include polyethylene terephthalate and copolymerized polyesters, that is, copolymerized polyethylene terephthalate in which isophthalic acid, 2,6-naphthalene dicarboxylic acid, adipic acid, diethylene glycol, neopentyl glycol, cyclohexanedimethanol, etc. are copolymerized. It will be done. Among these, polyethylene terephthalate is preferred.

[0034] The polyester for forming the body is prepared by adding various compounding agents such as crosslinking agents, heat stabilizers, weather stabilizers, antistatic agents, lubricants, mold release agents, inorganic fillers, pigment dispersants, pigments or dyes. It may be included as long as it does not impair the purpose of the invention.

[0035] Saturated polyester bottle 1 according to the present invention
The spout portion 2 is made of (i) polyethylene terephthalate;
Since it is made of a piece-forming polyester composition containing (ii) polybutylene terephthalate and (iii) talc and/or titanium dioxide, it has excellent heat resistance, mechanical strength, and dimensional accuracy. In addition, the torso 3 is
Since it is made of stretched and molecularly oriented saturated polyester, it has excellent heat resistance, mechanical strength, and dimensional accuracy, as well as excellent transparency. Since the bottle according to the present invention has excellent heat resistance, the spout 2 will not be deformed even when filled with liquid at a high temperature.

Next, a method for manufacturing a saturated polyester bottle according to the present invention will be specifically explained. The method for manufacturing a bottle according to the present invention first includes (i) polyethylene terephthalate, (ii) polybutylene terephthalate,
(iii) A piece-forming polyester composition containing talc and/or titanium dioxide is injected into a mold to form a bottle mouth-forming piece. At this time, it is desirable that the heating temperature of the piece-forming polyester composition is 50 to 150°C, preferably 70 to 140°C.

[0037] Next, the body-forming polyester is injected into the mold into which the bottle mouth-forming piece is inserted, and the bottle mouth-forming piece and the preform body are integrally molded. The heating temperature of the polyester for forming the body portion varies depending on the polyester used, but in the case of polyethylene terephthalate, which is preferably used in the present invention, it is preferably 270 to 310°C. This preform body becomes the bottle body when the preform is stretch blow molded.

At this time, as shown in FIG. 2, the piece-forming polyester composition is injected into the mold 11 from the first injection molding machine
The injection bottle cap forming piece 5 is molded, and then,
A preform may be manufactured by injecting polyester for forming the body from the second injection molding machine 15 into the mold 11 to form the preform body 4. Alternatively, as shown in FIG. Using a mold 12 for molding only the piece for forming the bottle mouth part, mold the piece 5 for forming the bottle spout part in advance,
Next, this bottle cap forming piece 5 is placed in another mold 13.
The preform may be manufactured by inserting the polyester into the mold 13 and injecting the polyester for forming the body into the mold 13 to form the preform body 4.

Thereafter, the preform is heated to a temperature suitable for stretching and stretch-blow molded to form a bottle. Note that the bottle may be heat set at the same time as stretch blow molding, or may be heat set after molding.

[0040]

[Effects of the Invention] The bottle cap forming piece according to the present invention comprises (i) polyethylene terephthalate, (ii) polybutylene terephthalate, (iii) talc and/or
Alternatively, since it is made of a polyester composition containing a certain proportion of titanium dioxide, it has excellent heat resistance, dimensional stability, and mechanical strength, as well as excellent mold release properties during molding.

[0041] The saturated polyester bottle according to the present invention has a spout portion made of (i) polyethylene terephthalate and (i) polyethylene terephthalate.
It is made of a polyester composition containing i) polybutylene terephthalate and (iii) talc and/or titanium dioxide in a certain proportion, and the body is made of stretched saturated polyester, so the spout part is heat resistant and dimensionally stable. The body has excellent heat resistance, dimensional stability, and mechanical strength, and has excellent transparency. Furthermore, since such a bottle has excellent heat resistance, the spout does not deform even if it is filled with liquid at a high temperature.

[0042] The method for producing a saturated polyester bottle according to the present invention does not require a heating process to crystallize the mouthpiece of the molded bottle, so it has excellent heat resistance, dimensional stability, and mechanical strength. A bottle with a spout can be manufactured in a short molding cycle.

[0043]

[Examples] The present invention will be explained below with reference to Examples, but the present invention is not limited to these Examples.

In the present invention, the physical properties of the bottle mouth-forming piece and the bottle are measured as follows. [Buckling strength] Maximum load (kg) when a compressive load is applied to a piece for forming a bottle cap part left in an oven at 90°C for 10 minutes using an Instron tensile tester, and deforms to 5%. was taken as the buckling strength.

[Dimensional Change] Dimensional changes in the diameter and height of the spout after immersion in hot water at 90° C. for 10 minutes were measured and calculated using the following formula.

[Moldability] Ease of removal from a mold heated to 120°C (mold releasability).

○: When the mold can be easily released by operating the extraction pin. ×: When it clings to the mold (core part) and is difficult to release from the mold. [Appearance] Appearance of the spout after being removed from the mold.

○: No dents, distortions, uneven color, etc.
And if it's shiny. ×: When any one of dents, distortions, uneven color, and poor gloss is present. [Capping property] Capping was carried out under a load of 180 kg, and the presence or absence of cracks and chips in the spout was examined.

○: There were no cracks or chips. ×: There were cracks or chips. [Drop impact resistance] A bottle filled with hot water and capped with a load of 180 kg was dropped from a height of 10 cm with the spout facing down onto a steel plate tilted at 20 degrees with respect to the horizontal plane. Checked for air leakage.

○: There was no water leakage or air leakage. ×: There was water leakage or air leakage.

[0051]

[Example 1] 51 parts by weight of polyethylene terephthalate [J125 manufactured by Mitsui Pet Resin Co., Ltd.] and polybutylene terephthalate [1401-X06 manufactured by Toray Industries, Inc.]
200 parts by weight of a polyester composition containing 30 parts by weight of talc [High Filler 15DS manufactured by Matsumura Sangyo Co., Ltd.], 18 parts by weight of titanium dioxide (anatase type) [TaipekuTM manufactured by Ishihara Sangyo Co., Ltd.] Heat to 1°C
A piece for forming an injection bottle spout was molded into a mold heated to 20°C.

Table 1 shows the results of measuring the physical properties of the thus obtained piece for forming a bottle cap. Next, polyethylene terephthalate [J125 manufactured by Mitsui Pet Resin Co., Ltd.] was heated to 280°C and injected into a mold into which the above-mentioned piece for forming the bottle spout was inserted to form a preform body to produce a preform. did. The mold temperature at this time was 10°C.

[0053] This preform was heated to 150°C and stretched and blown to form a bottle. The physical properties of the bottle thus obtained were measured. The results are shown in Table 1.

[0054]

[Examples 2 to 4] A piece for forming a bottle spout and a bottle were prepared in the same manner as in Example 1, except that the proportions of polyethylene terephthalate, polybutylene terephthalate, talc, and titanium dioxide were changed as shown in Table 1. Molded. The results are shown in Table 1.

[0055]

[Comparative Examples 1 and 2] A piece for forming a bottle spout and a bottle were prepared in the same manner as in Example 1, except that the proportions of polyethylene terephthalate, polybutylene terephthalate, talc, and titanium dioxide were changed as shown in Table 1. Molded. The results are shown in Table 1.

[0056]

[Table 1]

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram of a bottle according to the present invention.

FIG. 2 is an explanatory diagram of a method for manufacturing a bottle according to the present invention.

FIG. 3 is an explanatory diagram of a method for manufacturing a bottle according to the present invention.

[Explanation of symbols]

1 bottle 2. Spout part 3 Torso 4 Preform body 5 Piece for forming bottle spout 11-13 Mold 14-17 Injection molding machine

Claims (3)

[Claims] Claim 1: (i) polyethylene terephthalate; (ii) polybutylene terephthalate; (ii)
i) A piece for forming a bottle spout, which is made of a polyester composition containing talc and/or titanium dioxide. 2. A polyester bottle comprising a spout and a body, the spout being made of polyester containing (i) polyethylene terephthalate, (ii) polybutylene terephthalate, and (iii) talc and/or titanium dioxide. A bottle made of saturated polyester, characterized in that the body is made of stretched saturated polyester. Claim 3: (i) polyethylene terephthalate; (ii) polybutylene terephthalate; (ii)
i) A polyester composition containing talc and/or titanium dioxide is injected into a mold to form a bottle cap forming piece, and then the mold into which the bottle cap forming piece is inserted is saturated. Inject polyester,
A method for producing a saturated polyester bottle, which comprises forming a preform body to obtain a preform, and stretching and blow molding the obtained preform.