JPH07156934A - Polyethylene terephthalate bottle - Google Patents

Abstract

PURPOSE:To provide an excellent polyethylene terephthalate bottle which does not generates cracks or depression on filling and sterilizing lines with a high temperature. CONSTITUTION:A dynamic storage elastic modulus E' which is measured at the maximum diameter part of a bottle by a frequency of 10Hz is 1.1X10<11>-1.4 X10<11>dyn/cm<2> at 30 deg.C, and is 9.0 X10<10>-1.3 X10<11>dyn/cm<2>, and the dynamic storage elastic modulus E' changes monotonously together with a temperature in a temperature range of 30-90 deg.C.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyethylene terephthalate bottle which is free from cracks or dents on a line for filling and sterilizing contents at high temperatures.

[0002]

2. Description of the Related Art Recently, a biaxially stretch blow molded polyethylene terephthalate bottle has begun to be used as a container for filling and sterilizing sake, sauce, fruit juice and the like at high temperature. However, there is a problem that the polyethylene terephthalate bottle remains in a high temperature and is brought into contact with an adjacent bottle or device in order to be filled and sterilized at a high temperature, and a crack or a dent is generated at a portion to which most force is applied.

[0003]

The present invention is intended to provide an excellent polyethylene terephthalate bottle which does not cause cracks or dents on a high temperature filling and sterilization line, and the gist thereof is the maximum diameter portion of the bottle. Frequency 10Hz
Dynamic storage elastic modulus E'measured at 30 ° C. is 1.1 × 10 ^{11 to} 1.4 × 10 ¹¹ dyn / c
m ² 90 ° C. 9.0 × 10 ^{10 to} 1.3 × 10 ¹¹ dyn / c
The polyethylene terephthalate bottle is characterized in that it is m ² and changes monotonically with temperature in the temperature range of 30 to 90 ° C.

On the filling line, adjacent bottles come into contact with each other and exert a force. The part where the force is applied is
Although it depends on the design of the bottle, it is usually the maximum diameter part on the lower side of the bottle body.

Dynamic storage modulus E'at 30 ° C. is 1.1 × 1
Less than 0 ¹¹ dyn / cm ² or 9.0 × at 90 ° C.
When it is less than 10 ¹⁰ dyn / cm ² , the bottle is dented on the line for high temperature filling and the like because it is soft.

The dynamic storage elastic modulus E'at 30 ° C. is 1.
Above 4 × 10 ¹¹ dyn / cm ² or above 1.3 × 10 ¹¹ dyn / cm ² at 90 ° C., the bottle breaks because it becomes stiff and brittle.

When the dynamic storage elastic modulus E ′ satisfies the above requirements, neither cracks nor dents occur. Moreover, since the dynamic storage elastic modulus E ′ changes monotonously with temperature in the temperature range of 30 to 90 ° C., the dynamic storage elastic modulus E ′ always maintains the appropriate range even if the temperature changes in the range of 30 to 90 ° C. Keeps, no cracks or dents occur.

In order to obtain the polyethylene terephthalate bottle of the present invention, E'becomes smaller when the resin temperature during blow stretch molding is raised, and E'becomes larger when the mold temperature is raised. By adjusting the molding temperature and the temperature of the blow mold, the dynamic storage elastic modulus E ′ can be kept within the range of the present invention.

In the present invention, the method for measuring the dynamic storage elastic modulus E'is defined in "Test method for temperature dependence of dynamic viscoelasticity of plastic by non-resonant forced vibration method" described in JIS K7198. Based on the above, the measurement was performed under the following conditions.

Measuring apparatus: A solid analyzer II type (manufactured by Rheometrics Co., USA) is used, and measurement is carried out by a non-resonant forced bending vibration method under the conditions of constant strain of 0.1% or less and constant frequency of 10 Hz.

Specimen: polyethylene terephthalate bottle from the bottom of the side of the body, width 5 mm, thickness 0.3-0.6
A rectangular piece having a size of mm and a length of about 50 mm is used. The test piece cut out from the polyethylene terephthalate bottle is immediately adjusted after being adjusted for 88 hours or more under the conditions of 23 ° C. ± 2 ° C. and 50 ± 5% relative humidity.

Measuring temperature: The temperature of the test piece is measured at 90 ° C. to 30 ° C. while linearly lowering the temperature at 2 ° C./minute so that the temperature of the test piece becomes equilibrium.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments will be described below with reference to the accompanying drawings.

FIG. 1 is a front view showing an example of the polyethylene terephthalate bottle of the present invention, and FIG. 2 is a graph showing the relationship between the dynamic storage elastic modulus E'and the temperature.

In FIG. 1, a body diameter D ₁ is 90 mm, a body lower maximum diameter portion 11 has a diameter D ₂ of 93 mm, and a height H is 310 m.
Table 1 shows the dynamic storage elastic modulus E'by adjusting the molding temperature of the preform and the temperature of the blow mold in biaxially stretch blow molding a polyethylene terephthalate bottle having a volume of 1.5 m and a content of 1.5 liters. As shown, at 30 ° C. 1.07 × 10 ^{11 to} 1.44 × 10 ¹¹ dyn
/ Cm ² 90 ° C., 8.94 × 10 ^{10 to} 1.32 × 10 ¹¹ dyn
/ In the range of cm ^2, and the relationship between the dynamic storage modulus E'and temperature 2
No. that has the pattern shown in. 1-4 polyethylene terephthalate bottles were produced.

Then, these polyethylene terephthalate bottles were filled with warm water of 80 ° C. on a filling line, capped, sealed, and further conveyed on the line. Shown in.

As shown in Table 1, the dynamic storage elastic modulus E'is 1.07 × 10 ^{11 at} 30 ° C. and 8.94 × 1 at 90 ° C.
0 ¹⁰ and the small No. No. 1 has a dent on the lower part 11 of the body, and at 30 ° C 1.44 × 10 ¹¹ dyn / c
m ^2, at 90 ℃ 1.32 × 10 ¹¹ large as dyn / cm ² No. No. 4 produced cracks, while at 30 ° C., 1.1 × 10 ^{11 to} 1.4 × 10 ¹¹ dyn / cm ² , 90
9.0 ° C ^{10 to} 1.3 × 10 ¹¹ dyn / cm ^{2 at} ° C.
Within the range of No. Nos. 2-3 had a good appearance with neither dents nor cracks.

[0018]

[Table 1]

[0019]

EFFECTS OF THE INVENTION The present invention has a dynamic storage elastic modulus E'measured at a frequency of 10 Hz of 1.1 × 10 ^{11 to} 1.4 × 10 ¹¹ dyn / c at the maximum diameter of the bottle of 30 ° C.
m ² 90 ° C. 9.0 × 10 ^{10 to} 1.3 × 10 ¹¹ dyn / c
m ² and a polyethylene terephthalate bottle characterized by monotonically changing with temperature in the temperature range of 30 to 90 ° C., excellent filling at high temperature and free from cracks or dents on the sterilization line Is.

[Brief description of drawings]

FIG. 1 is a front view showing an example of a polyethylene terephthalate bottle of the present invention.

FIG. 2 is a graph showing the relationship between dynamic storage elastic modulus E ′ and temperature.

[Explanation of symbols]

 11 Lower body maximum diameter

Claims (1)

[Claims] 1. A frequency of 10 at the maximum diameter portion of the bottle.
The dynamic storage elastic modulus E'measured in Hz is 1.1 × 10 ^{11 to} 1.4 × 10 ¹¹ dyn / c at 30 ° C.
m ² 90 ° C. 9.0 × 10 ^{10 to} 1.3 × 10 ¹¹ dyn / c
A polyethylene terephthalate bottle characterized in that it is m ² and changes monotonically with temperature in the temperature range of 30 to 90 ° C.