JP2883438B2 - Saturated polyester bottle and method for producing the same - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a saturated polyester bottle and a method for producing the same, and more particularly, to a saturated polyester bottle having excellent heat resistance and a transparent body, and a method for producing the same. .

Technical Background of the Invention and Problems Thereof Conventionally, glass has been widely used as a material for containers such as seasonings, oils, juices, carbonated drinks, beer, sake, cosmetics, and detergents. However, since the production cost of the glass container is high, a method of collecting an empty container after normal use and circulating and reusing the container has been adopted. Further, since the glass container is heavy, the transportation cost is increased, and the glass container is liable to be broken and is inconvenient to handle.

In an effort to overcome these drawbacks of glass containers, the conversion from glass containers to various plastic containers has recently been rapidly progressing. As the material, various plastics are adopted according to the kind of the filling content and the purpose of use. Among these plastic materials, saturated polyester resins such as polyethylene terephthalate have mechanical strength, heat resistance and transparency. Because of its excellent gas barrier properties, it is used as a material for containers for juices, soft drinks, carbonated drinks, seasonings, detergents, and cosmetics. Among these uses, bottles for filling juices, soft drinks, and carbonated beverages are required to be sterilized and filled at high temperatures, and therefore, bottles are formed from heat-resistant resins that can withstand high-temperature filling. And all of these filling bottles are required to be transparent.

By the way, a bottle made of a saturated polyester such as polyethylene terephthalate usually comprises a plug portion, a body portion and a bottom portion, and the body portion is molecularly oriented because it is stretch-molded, so that transparency, heat resistance and Excellent mechanical strength. On the other hand, since the plug portion and the bottom portion are hardly stretch-formed, these portions are inferior in heat resistance and have a problem that they are deformed during sterilization or hot filling.

In order to solve such problems, for example,
JP-A-33101 discloses a saturated polyester bottle in which only the plug portion is heat-treated and crystallized. However, a saturated polyester such as polyethylene terephthalate has a low crystallization rate and therefore has to be heated for a long period of time, which causes problems such as a troublesome work and a decrease in dimensional accuracy of the plug.

JP-A-56-23242 discloses a bottle formed from a resin composition obtained by blending polyethylene terephthalate with an inorganic filler. Furthermore, Japanese Patent Application No. 58
JP-20635 discloses a plastic container made of a thermoplastic resin containing an inorganic filler having a specific particle size.
However, in the bottle as described above, since the body is also formed of polyethylene terephthalate mixed with an inorganic filler, there is a problem that the body is also inferior in transparency.

Object of the Invention The present invention is intended to solve the above-mentioned problems associated with the prior art at once, in which not only the body but also the plug and the bottom are excellent in heat resistance, and the body is transparent. It is an object of the present invention to provide a saturated polyester bottle having excellent properties and a method for producing the same.

SUMMARY OF THE INVENTION A first saturated polyester bottle according to the present invention is a saturated polyester bottle comprising a plug, a body and a bottom, wherein the plug is in an unstretched state showing a glass transition point of 85 ° C. or higher. A first saturated polyester or an unstretched polycarbonate having a glass transition point of 85 ° C. or more; a body portion formed of a second stretched saturated polyester; and a bottom portion formed of an unstretched or stretched second polyester. It is characterized by being composed of saturated polyester.

The second saturated polyester bottle according to the present invention is a saturated polyester bottle comprising a plug portion, a body portion, and a bottom portion, wherein the plug portion has a glass transition point of 85 ° C. or higher and is in an unstretched state. Consisting of an unstretched polycarbonate having a glass transition point of 85 ° C. or more, and a body made of a stretched second saturated polyester having a glass transition point of 85 ° C. or more. It is characterized by being composed of the first saturated polyester in a state or an unstretched polycarbonate having a glass transition point of 85 ° C. or more.

On the other hand, the first method for producing a saturated polyester bottle according to the present invention comprises the first saturated polyester bottle supplied with the second saturated polyester.
Using a plurality of injection molding machines having an injection molding machine and a second injection molding machine supplied with a first saturated polyester having a glass transition point of 85 ° C or higher or a polycarbonate having a glass transition point of 85 ° C or higher. Injecting a first polyester having a glass transition point of 85 ° C. or higher or a polycarbonate having a glass transition point of 85 ° C. or higher to form a preform plug, and then injecting a second saturated polyester The preform body and bottom are formed, and the obtained preform is blow-molded.

Further, the method for producing a second saturated polyester bottle according to the present invention is characterized in that the first saturated polyester bottle is supplied with the first saturated polyester bottle.
Using a plurality of injection molding machines having an injection molding machine and a second injection molding machine supplied with a first saturated polyester having a glass transition point of 85 ° C or higher or a polycarbonate having a glass transition point of 85 ° C or higher. Injecting a first polyester exhibiting a glass transition point of 85 ° C. or higher to form a preform plug portion, injecting a second saturated polyester to form a preform body portion, A first polyester having a glass transition point of 85 ° C. or higher or a polycarbonate having a glass transition point of 85 ° C. or higher is injected to form a bottom of the preform, and the obtained preform is blow-molded. .

DETAILED DESCRIPTION OF THE INVENTION Hereinafter, the saturated polyester bottle according to the present invention and a method for producing the same will be specifically described.

The first saturated polyester bottle 1 according to the present invention comprises:
As shown in FIG. 1, it comprises a plug part 2, a body part 3, and a bottom part 4.

The plug 2 of the bottle 1 is made of a first saturated polyester in an unstretched state having a glass transition point of 85 ° C. or higher or 85 ° C.
It is formed from an unstretched polycarbonate exhibiting the above glass transition point.

The plug 2 as described above is not substantially stretched. Since the plug 2 is made of the unstretched first saturated polyester having a glass transition point of 85 ° C. or higher or the unstretched polycarbonate having a glass transition point of 85 ° C. or higher, it has excellent heat resistance. It does not undergo thermal deformation during sterilization or hot filling, and has excellent dimensional stability.

On the other hand, the body 3 of the bottle 1 is made of uniaxially or biaxially stretched, preferably biaxially stretched second saturated polyester. Since the body 3 is formed of a stretched and molecularly oriented saturated polyester, the body 3 is excellent in transparency, heat resistance, and mechanical strength. The area stretching ratio of the stretched second saturated polyester forming the body 3 is 3 to 30 times, preferably about 5 to 25 times.

The bottom portion 4 of the bottle 1 is formed of the second saturated polyester that has not been drawn or drawn at a low draw ratio. That is, the second saturated polyester forming the bottom 4 of the bottle 1 is hardly stretched when the preform is blow-molded to manufacture the bottle, or is stretched at a low area stretching ratio, for example, about 1 to 3 times. I have.

Next, a second saturated polyester bottle according to the present invention will be described. As shown in FIG. 2, the bottle 10 is formed of a plug part 2, a body part 3, and a bottom part 4, The stopper 2 and the body 3 are the same as the first saturated polyester bottle as described above, and the bottom 4 is at 85 ° C.
It is made of a first saturated polyester having the above glass transition point or a polycarbonate having a glass transition point of 85 ° C. or higher, and has not been stretched or has been stretched at a low area stretching ratio, for example, 1 to 3 times.

Thus, by forming the bottom part 4 from an unstretched or low-stretched first saturated polyester exhibiting a glass transition point of 85 ° C. or more or an unstretched polycarbonate exhibiting a glass transition point of 85 ° C. or more, Further, a bottle having excellent heat resistance at the bottom can be obtained.

In some cases, the plug portion 2 is formed from a composition obtained by blending a second saturated polyester as described later with an unstretched first saturated polyester having a glass transition point of 85 ° C. or higher. It may be formed from a composition obtained by blending a second saturated polyester with an unstretched polycarbonate having a glass transition point of 85 ° C. or higher, and further exhibit a glass transition point of 85 ° C. or higher. It may be formed from a composition containing the unstretched first saturated polyester and the unstretched polycarbonate having a glass transition point of 85 ° C. or higher.

Next, the first saturated polyester having a glass transition point of 85 ° C. or higher used in the present invention will be described.
As the first saturated polyester having a glass transition point of at least 85 ° C., a conventionally known saturated polyester having a glass transition point of at least 85 ° C. can be used. Specifically, for example, bisphenol A and terephthalic acid dichloride can be used. Alternatively, a saturated polyester (U polymer) obtained by interfacial polycondensation with isophthalic acid dichloride is used. The glass transition temperature of this saturated polyester is about 193 ° C
It is.

Or as a first saturated polyester having a glass transition point of 85 ° C. or higher, for example, Polyesters having the following repeating units can also be used.

Further, as an unstretched first saturated polyester exhibiting a glass transition point of 85 ° C. or higher, for example, Polyesters having the following repeating units can also be used.

As the polycarbonate exhibiting a glass transition point of 85 ° C. or higher, specifically, a polycarbonate obtained by a transesterification reaction of bisphenol A with diphenyl carbonate or a desalting polycondensation reaction of bisphenol A with phosgene is used. The glass transition point of such a polycarbonate is about 150 ° C.

Alternatively, as the polycarbonate having a glass transition point of 85 ° C. or higher, a polycarbonate copolymer obtained by copolymerizing the above-mentioned first saturated polyester component and the polycarbonate component can be used.

On the other hand, the second saturated polyester resin used in the present invention includes terephthalic acid or an ester-forming derivative thereof (eg, lower alkyl ester, phenyl ester, etc.) and ethylene glycol or an ester-forming derivative thereof (eg, monocarboxylic acid ester). And polyethylene terephthalate obtained from ethylene oxide or the like. The polyethylene terephthalate may be copolymerized with less than about 20 mole% of other dicarboxylic acids or glycols. Such dicarboxylic acid components include, for example, phthalic acid, isophthalic acid, naphthalene dicarboxylic acid, diphenyl dicarboxylic acid, aromatic dicarboxylic acids such as diphenoxyethane dicarboxylic acid,
It is derived from aliphatic dicarboxylic acids such as adipic acid, sebacic acid, azelaic acid and decanedicarboxylic acid, and alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid.
Glycol components include trimethylene glycol, propylene glycol, tetramethylene glycol, neopentyl glycol, hexamethylene glycol, aliphatic glycols such as dodecamethylene glycol, alicyclic glycols such as cyclohexanedimethanol, bisphenols, hydroquinone, 2, It is derived from aromatic diols such as 2-bis (4-β-hydroxyethoxyphenyl) propane.

Hereinafter, polyethylene terephthalate particularly preferably used in the present invention will be described. That is, preferred polyethylene terephthalate is Is from 90.0 to 99.5 mol%, preferably from 95.0 to 99.5 mol%.
Mol%, particularly preferably in the range of 97.0 to 99.0 mol%, The content of the dioxyethylene terephthalate component unit (b) represented by the formula is 0.5 to 10.0 mol%, preferably 0.5 to 10 mol%.
Mol% is particularly preferably in the range of 1.0 to 3.0 mol%.

Such preferred polyethylene terephthalate is
The ethylene terephthalate component unit (a) represented by the general formula [I] and the dioxyethylene terephthalate component unit (b) represented by the general formula [II] are randomly arranged to form an ester bond. To form polyester. The fact that the polyethylene terephthalate is substantially linear is confirmed by the fact that the polyethylene terephthalate dissolves in o-chlorophenol.

The o of such preferred polyethylene terephthalate
-Intrinsic viscosity [η] measured in chlorophenol at 25 ° C
Is in the range of 0.50 to 1.0 dl / g, preferably 0.60 to 0.95 dl / g, particularly preferably 0.62 to 0.90 dl / g.

In addition, the temperature rise crystallization temperature (Tcc ₁ ) of such a preferable polyethylene terephthalate when it is heated at a rate of 10 ° C./min by a differential scanning calorimeter (DSC) is 130 ° C. or higher, preferably 135 ° C. ~ 185 ° C, particularly preferably 140 ~ 180 ° C
In the range.

In addition, the above-mentioned preferable temperature rise crystallization temperature (Tcc ₁ ) of polyethylene terephthalate is measured by the following method. That is, using a DSC-2 type differential scanning calorimeter manufactured by Perkin Elmer, at about 140 ° C. under a pressure of about 5 mmHg for about 5 hours.
A sample of about 10 mmg from the center of a saturated polyester chip dried for more than an hour is sealed in a liquid aluminum pan under a nitrogen atmosphere and measured. The measurement conditions were as follows: first, the temperature was rapidly raised from room temperature, melted and held at 290 ° C for 10 minutes, then rapidly cooled to room temperature, and then the peak temperature of the exothermic peak detected when the temperature was raised at a rate of 10 ° C / min. Ask for.

Next, a method for producing the above-mentioned saturated polyester bottle will be described.

First, the method for producing the first saturated polyester bottle according to the present invention as described above will be described with reference to the production apparatus shown in FIG.
Is supplied to the first injection molding machine 21 and the second saturated polyester which has a glass transition point of 85 ° C. or more or the second saturated polyester which has a glass transition point of 85 ° C. or more.
Using a plurality of injection molding machines having an injection molding machine 23, a first saturated polyester having a glass transition point of 85 ° C or more or a glass transition point of 85 ° C or more Is injected to form a preform plug. In addition, this preform plug becomes a plug of a bottle when the preform is blow molded.

Next, the second saturated polyester is injected into the mold 24 from the first injection molding machine 21, and the preform body and the bottom are formed continuously with the preform plug. The preform body and bottom become the body and bottom of the bottle, respectively, when the preform is blow molded.

Next, when the preform obtained as described above is blow molded, a saturated polyester bottle is obtained. The blow molding conditions are as shown below.

After heating and maintaining the body and bottom of the preform in a temperature range of 80 ° C to 150 ° C, preferably 85 ° C to 130 ° C, the preform is stretched in the stretching direction in a stretching lot, and air pressure 25
Heat setting is performed at the same time as blow molding in a bottle mold at normal temperature to 200 ° C, preferably 100 ° C to 180 ° C at kg / cm ² . By doing so, a bottle excellent in transparency and heat resistance (having almost no deformation even when filled with hot water of 60 ° C. or higher, preferably 80 ° C. or higher) can be obtained.

In the saturated polyester bottle obtained in this manner, the plug portion is made of an unstretched first saturated polyester having a glass transition point of 85 ° C. or more or an unstretched polycarbonate having a glass transition point of 85 ° C. or more. The trunk is made of a stretched second saturated polyester, and the bottom is made of an unstretched or stretched second saturated polyester.

Next, the method for producing the second saturated polyester bottle according to the present invention will be described.
A first injection molding machine 21 supplied with 20 and a second injection molding machine 23 supplied with a first saturated polyester having a glass transition point of 85 ° C. or higher or a polycarbonate 22 having a glass transition point of 85 ° C. or higher. First, from a second injection molding machine 23, a first saturated polyester exhibiting a glass transition point of 85 ° C. or higher or a polycarbonate 22 exhibiting a glass transition point of 85 ° C. or higher is supplied from a second injection molding machine 23 to a mold 24. Inject to form a preform plug.

Next, the second saturated polyester is injected into the mold 24 from the first injection molding machine 21, and the preform body is formed continuously with the preform plug.

This preform body becomes the body of the bottle when the preform is blow molded.

Next, a first saturated polyester having a glass transition point of 85 ° C. or higher or a polycarbonate having a glass transition point of 85 ° C. or higher is injected from the second injection molding machine 23 to the mold 24,
The preform bottom is formed continuously with the preform body. This preform bottom will be the bottom of the bottle when the preform is blow molded.

Next, the preform obtained as described above is blow-molded under the same conditions as above to obtain a saturated polyester bottle.

In the saturated polyester bottle obtained in this manner, the plug portion is made of an unstretched first saturated polyester having a glass transition point of 85 ° C. or more or an unstretched polycarbonate having a glass transition point of 85 ° C. or more. The body portion is made of a stretched second saturated polyester, and the bottom portion is a first saturated polyester in an unstretched state having a glass transition point of 85 ° C. or more or a glass transition point of 85 ° C. or more. It is made of a stretched polycarbonate.

Effect of the Invention In the saturated polyester bottle according to the present invention, the plug portion has excellent heat resistance and does not undergo thermal deformation, and the body portion has excellent transparency and heat resistance.

[Brief description of the drawings]

1 and 2 are cross-sectional views of a saturated polyester bottle according to the present invention, and FIG. 3 is a schematic explanatory view of an apparatus used for manufacturing the bottle. 1,10 bottle, 2 bottle cap 3 body, 4 bottom

Continuation of the front page (51) Int.Cl. ⁶ identification symbol FI C08G 64/06 C08G 64/06 // B29K 67:00 69:00 B29L 22:00 (56) References JP-A-63-41 (JP, A) JP-A-63-239011 (JP, A) JP-B-60-17693 (JP, B2) (58) Fields investigated (Int. Cl. ⁶ , DB name) B29C 49/00-49/80 B29B 11 / 00-11/16 B29C 45 / 13,45 / 14 C08G 64/06 C08G 63/60

Claims (4)

(57) [Claims] 1. A saturated polyester bottle comprising a plug portion, a body portion and a bottom portion, wherein the plug portion is an unstretched first saturated polyester having a glass transition point of 85 ° C. or more or a glass of 85 ° C. or more. A saturated polyester, comprising a polycarbonate in an unstretched state showing a transition point, a trunk portion comprising a stretched second saturated polyester, and a bottom portion comprising an unstretched or stretched second saturated polyester. Bottle. 2. A saturated polyester bottle comprising a plug portion, a body portion and a bottom portion, wherein the plug portion is an unstretched first saturated polyester having a glass transition point of 85 ° C. or more or a glass of 85 ° C. or more. The body is made of a stretched second saturated polyester having a transition point, and the body is made of a stretched second saturated polyester having a glass transition point of 85 ° C. or more. A saturated polyester bottle comprising an unstretched polycarbonate exhibiting a glass transition point of not lower than ° C. 3. A method according to claim 1, wherein the first saturated polyester is supplied.
Using a plurality of injection molding machines having an injection molding machine and a second injection molding machine supplied with a first saturated polyester having a glass transition point of 85 ° C or higher or a polycarbonate having a glass transition point of 85 ° C or higher. Injecting a first saturated polyester having a glass transition point of 85 ° C. or higher or a polycarbonate having a glass transition point of 85 ° C. or higher to form a preform plug, and then injecting a second saturated polyester A method for producing a saturated polyester bottle, comprising: forming a preform body and a bottom portion by blow molding; and blowing the obtained preform. 4. A method according to claim 1, wherein the first saturated polyester is supplied.
Using a plurality of injection molding machines having an injection molding machine and a second injection molding machine supplied with a first saturated polyester having a glass transition point of 85 ° C or higher or a polycarbonate having a glass transition point of 85 ° C or higher. The first saturated polyester having a glass transition point of 85 ° C. or higher or the polycarbonate having a glass transition point of 85 ° C. or higher is injected to form a preform plug, and the second saturated polyester is injected to form a plug. Forming a reform body, and then exhibiting a glass transition point of 85 ° C. or higher as described above.
A method for producing a saturated polyester bottle, comprising: injecting a saturated polyester or a polycarbonate exhibiting a glass transition point of 85 ° C. or more, molding a preform bottom, and blowing the obtained preform.