JPH02233341A - Bottle - Google Patents

Abstract

PURPOSE:To achieve a drastic improvement in the gas barrier property by producing a bottle from a polyethylene naphthalate resin in such a way that the distribution curves of the X-ray interference strength at a plurality of spots on the circumferential surface in the middle of the drumlike part have specific maximum values. CONSTITUTION:A bottle 1 consists of a mouth part 2, a shoulderlike part 3, a drumlike part 4, a peripheral bottom 5, and a bottom 6. It is observed that, with a probability of not less than 80% at the lowest estimate, the distribution curves of the X-ray interference strength at a plurality of spots on the circumferential surface in the middle of the drumlike part 4 have maximum values in the beta-angle ranges of 0 deg.+ or -20 deg. and 90 deg.+ or -20 deg.. To make such a bottle 1, first a prefoam is obtained from polyethylene naphthalate resin; the prefoam is made in a short form, with the diameter also reduced as occasion demands; the prefoam is so highly stretched as to bring the draw index to 130cm or more, and then subjected to blow molding. By subjecting the resulting prefoam to biaxial stretching and to molding by a molding machine a bottle 1 having a drastically improved gas-barrier property to oxygen or carbon dioxide is obtainable. The product is excellent also in heat resistance, transparency, and mechanical strength.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to polyethylene naphthalate resin bottles, and more specifically, polyethylene naphthalate resin bottles having excellent gas barrier properties, transparency, and heat resistance. Regarding resin bottles.

TECHNICAL BACKGROUND OF THE INVENTION Conventionally, glass has been widely used as containers for seasonings, oils, juices, carbonated drinks, beer, Japanese sake, cosmetics, detergents, and the like. However, manufacturing costs for glass containers are high.
・Because of the high cost, a method is adopted in which empty containers are collected after normal use and recycled for reuse. In addition, glass containers are heavy, which increases shipping costs, and they also have drawbacks such as being easily damaged and inconvenient to handle.

In an attempt to overcome these drawbacks of glass containers, there has recently been a rapid shift from glass containers to various plastic containers. Various plastics are used as materials depending on the type of filling contents and the purpose of use. Among these plastic materials, polyethylene terephthalate and polyethylene naphthalate have excellent 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, juices, soft drinks,
Blow-molded containers for filling carbonated beverages are required to be sterilized and filled at high temperatures, and for this reason, the blow-molded containers are required to be made of heat-resistant resin that can withstand high-temperature filling. All of these blow-molded containers for filling are required to have transparency and excellent shape stability with little variation in internal volume.

However, conventionally known bottles made of polyethylene terephthalate or polyethylene naphthalate have excellent gas barrier properties and heat resistance, but there are synthetic resin bottles that have even better gas barrier properties and heat resistance. 1
・It is hoped that the emergence of

The inventors of the present invention conducted intensive studies to obtain a stretched synthetic resin bottle with excellent gas barrier properties and heat resistance. It was found that a stretched bottle made of polyethylene naphthalate resin, in which the stretched polyethylene naphthalate resin has a peak at a specific position in the X-ray interference intensity distribution curve, has extremely excellent gas barrier properties and is also heat resistant. As a result, the present invention was completed.

OBJECTS OF THE INVENTION The present invention has been made in view of the above-mentioned points, and provides a polyethylene naphthalene 1. The Ll's purpose is to provide the following information.

Summary of the Invention The bottle according to the present invention is made of polyethylene naphthalate resin, and has an X-ray interference intensity distribution curve of at least 80% or more, preferably 90% or more, at multiple points on the circumference of the central part of the bottle body. 2. More preferably, the β angle has a probability of 95% or more. ±20° and β angle 9 0'±20
It is characterized by the fact that local maximum values are observed in both ranges.

Specific description of the invention The bowl according to the present invention will be specifically explained below.

In the present invention, polyethylene naphthalene resin is used to form the bowl. This polyethylene naphthalene-1 resin is an ethylene-2,6-
60 mol% or more of naphthalene i units, preferably 80%
More preferably, it is contained in an amount of 90 mol% or more, but it may contain structural units other than ethylene-2.6-naphthalate in an amount of less than 40 mol%.

Constituent units other than ethylene-2,6-naphthalate include terephthalic acid, isophthalic acid, 2,7-naphthalene dicarboxylic acid, 2,5-naphthalene dicarboxylic acid, diphenyl-4,4-dicarboxylic acid, and 4.4-dicarboxylic acid. Aromatic dicarboxylic acids such as '-diphenyl ether dicarboxylic acid, 4,4°-diphenylsulfone dicarboxylic acid, 4,4-diphenoxychetane dicarboxylic acid, dibromoterephthalic acid,
Aliphatic dicarboxylic acids such as adipic acid, azelaic acid, sebacic acid, and decanedicarboxylic acid, ■. Alicyclic dicarboxylic acids such as 4-cyclohexanedicarboxylic acid, cyclopropanedicarboxylic acid, and hexahydroterephthalic acid; hydroxycarboxylic acids such as glycolic acid, p-hydroxybenzoic acid, and p-hydroxybenzoic acid; Propylene glycol, 1-rimethylene glycol, diethylene glycol, 1-ramethylene glycol, pentamethylene glycol, hexamethylene glycol, decamethylene glycol, neopentylene glycol, p-xylene glycol, 1,4-cyclohexanedimethanol , bisphenol A1I”p-diphenoxysulfone, 1,4-bis(β-hydroxyethoxy)benzene, 2
．． Examples include structural units derived from 2-bis(pβ-hydroxyethoxyphenyl)brobane, polyalkylene glycol, p-phenylenebis(dimethylsiloxane), glycerin, and the like.

In addition, the polyethylene naphthalate resin used in the present invention contains structural units derived from polyfunctional compounds such as 1-rimesic acid, 1-limethylolethane, trimethylolpropane, 1-limethylolmethane, and pentaerythrol. It may be contained in a small amount, for example, 2 mol% or less.

Furthermore, the polyethylene naphthalate resin used in the present invention contains a small amount, for example 2 mol%, of structural units derived from monofunctional compounds such as benzoylbenzoic acid, diphenylsulfone monocarboxylic acid, stearic acid, methoxypolyethylene glycol, and phenoxypolyethylene glycol. It may be included in the following amounts.

Such polyethylene naphthalene-1 resin is substantially linear, which means that the polyethylene naphthalate-1 resin is substantially linear.
is confirmed by dissolving in 0-chlorophenol.

The intrinsic viscosity [η] of polyethylene naphthalene-1 measured in 0-chlorophenol at 258C is 0.2 to 1.1.
dΩ/g preferably 0.3-0.9 dρ/g particularly preferably 0.4-0. It is desirable that it be in the range of 8dρ/g.

Note that the intrinsic viscosity [η] of polyethylene naphthalate is measured by the following method. That is, polyethylene naphthalate to O-chlorophenol, 1 g/1
Dissolve at a concentration of 0 0 ml, measure the solution viscosity using an Ubbelohde capillary viscometer at 25°C, then gradually add 0-chlorophenol, measure the solution viscosity on the low concentration side, and measure the solution viscosity at 25 ° C. Extrapolate to % concentration to find the limiting viscosity ([η).

Additionally, a polyethylene naphthalate differential scanning calorimeter (
The heating crystallization temperature (TO) when the temperature is raised at a rate of 10°C/min using DSC) is 150°C or higher, preferably 160 to 230'C, particularly preferably 170 to 220°C.
It is desirable to be in the range of 0'C.

In addition, the temperature-elevated crystallization temperature (T
c) is measured by the following method. That is, using a PerkinElmer Model DSC-2 differential scanning calorimeter at about 140°C and under a pressure of about 5 + n + n H g.
A sample of about 10 mm of a thin piece from the center of a polyethylene naphthalate chip that has been dried for more than an hour is sealed in an aluminum pan for liquid under a nitrogen atmosphere and measured. The measurement conditions were as follows: First, the temperature was rapidly raised from room temperature, held at 290°C for 10 minutes, then rapidly cooled to room temperature, and then heated to 10°C/10°C.
The apex temperature of the exothermic peak detected when the temperature is raised at a heating rate of 10 minutes is determined.

Note that polyethylene naphthalate as described above can be manufactured by a conventionally known manufacturing method.

The polyethylene naphthalate used in the present invention includes various compounding agents that are usually added to polyester, such as heat-resistant stabilizers, weather-resistant stabilizers, antistatic agents, lubricants, mold release agents, pigment dispersants, pigments, or dyes. may be added within a range that does not impair the purpose of the present invention.

The bottle according to the present invention is made of stretched polyethylene naphthalate resin, and has X-ray interference intensity distribution curves at multiple points on the circumference of the central part of the bottle body.
With a probability of at least 80% or more, preferably 90% or more, and more preferably 95% or more,
It is characterized by the fact that maximum values are observed in both angle ranges of 90°±20°.

Below, a method for measuring the X-ray interference intensity distribution on the circumference of the central portion of a stretched bottle made of polyethylene naphthalate resin will be described. As an example, a bottle made of polyethylene naphthalate resin is shown in FIG.

When manufacturing such a bowl 1, a preform 7 is used, and this preform 7 is shown by a dotted line in FIG.

In the present invention, the center part of the body part 4 of such a stretched ball 1 is cut out, and samples (2 cm x 2 cm
) is cut out and fixed to the sample holder of the X-ray fiber sample stage. Note that the central portion of the body 4 refers to a portion centered at a position of ]/2 of the height of the bottle below from the imaginary curve 9 drawn at the lower end of the spout 2 in FIG.

The X-ray interference intensity distribution of the sample as described above is determined in III. The sample is rotated around the normal line to the sample surface, and the intensity distribution of a specific X-ray diffraction peak is obtained. The conditions for measurement are as follows.

X-ray diffraction device; Rigaku Denki RU300? -getl:
cu target (point 1/focus) Voltage/current: 50 kV, 300 mA Accessory parts: Fiber sample table slit 1/system: Collimator 1 mmφ Vertical width slit 1.9 mm Width slit I ■ 1.8 mm α Angle: 30° fixed 2θ: 15 .4° θ: 7.7° fixed β angle Rotation speed: 8°/min β angle was defined as follows.

When the circumferential direction of the bottle was oriented horizontally, it was defined as 0°, and when it was oriented vertically, it was defined as 90°.

The X-ray interference intensity distribution curve of the central sample of the bottle body obtained in this way is shown in FIG. Whether or not a maximum value is recognized in this X-ray interference intensity distribution curve is determined as follows. First, draw a tangent line at the lowest bottom of the intensity distribution curve and use it as the baseline. Then 0° to 360°
The height between the second lowest bottom and the baseline is Ib
shall be.

Next, calculate the smaller of the maximum values observed at 0±20° or 180°±20'.

When 0° (same as 360°) and the smaller of the maximum values observed at 90°±20° or 270″±20° are 190, both Io/■ and I9o/b are 1. When the value is 1 or more, preferably 1.15 or more, a maximum value is observed at 0°±20° or 90°±200.

Polyethylene naphthalate resin stretched tube I according to the present invention
- At least 80% or more in the X-ray interference intensity distribution curve at multiple points around the center of the bottle body.
The maximum value is observed in both the ranges of β angle 0±20° and 9°±20° with a probability of preferably 90% or more, and more preferably 95% or more.

On the other hand, in the conventionally known low-stretched polyethylene naphthalene resin bottle 1, the X
In line interference intensity distribution curve, less than 80% usually 60%
The probability of final height is β angle 00 ± 20° and β angle 9
No maximum value is observed in both ranges of 0'±20°.

Next, cut out a 34mm diameter piece from the center circumference of the stretched bottle body, attach it to the sample holder of the pole figure measuring device, and attach it to the 2θ-
Measure the pole figure of the 15,4° (0 1 0) plane.

The conditions for pole figure measurement are as follows.

(1) Equipment: Rigaku Denki K K■ RU300Cu film
Get Point Focus Voltage Current 50KV, 300mA Parts: Fully automatic pole measuring device (2) Measurement sample - Cut out a piece of 34 mmφ around the measurement point and fix it in a holder.

(3) Measurement conditions slit systemD. S. O. lR. S I S. S 4 Ni
The filter reflection method uses a limiting slit of 1.

Pole sample stage conditions Manual mode (1): I Continue
ous ScanMode (2) Alpl1a Start: OAlpha
stop: 40Alpha' Star
t: 40 Alpha stop: 90
Alpha SteI]: 10Beta
Start: 0Circular Measurement: Decker method +S
uhulz reflection method Peak 2θ = 15.4° B. G 2 θ =20. 0°γ No vibration of the center sample of the bottle body obtained in this way
An example of a line pole figure is shown in FIG. From this X-ray pole figure,
The pole point appears to be slightly shifted from the β angle of 0° 9o° 180' 270°, which indicates that the molecular chains of polyethylene naphthalate constituting the bottle are slightly deviated in the longitudinal and circumferential directions. However, this deviation is within the range of ±20' for the stretched bottle according to the invention.

The polyethylene naphthalene resin stretched ball 1 according to the present invention has a carbon dioxide gas permeability coefficient Pc defined as below of 0. 1 3aa-am/day-atm
Preferably 0. 1 2cc-cm/day-a
tm or less, more preferably 0. 1 0 ccφ
am/day-atm or less, and the average thickness coefficient tc of the center part of the bottle body excluding the mouthpiece defined as below is 0.2 or less, preferably 0.18 or less. is desirable.

Pc=PXf [where P is the carbon dioxide permeability of the entire bottle (cc/
day-atm) and f − S/V (am-1
), S is the inner surface area of the stretched bottle (excluding the inner surface of the spout), and ■ is the inner volume of the stretched bottle (excluding the volume of the spout). ] tc=txfX10 [where t is the average thickness (mm) of the central part of the body part of the bottle excluding the spout, and f is the same as above.

The carbon dioxide gas permeability P (cc/day * aim) of such a polyethylene naphthalene/resin bottle is:
Fully is determined as follows. In other words, dry ice is placed in a stretched blow-molded bottle at 23°C with an internal pressure of approximately 5 kg.
/ctl. After adjusting the volume and sealing, the bottle was left in a constant temperature room at 23°C and 50% RH, and the weight change over time was measured. Average amount of carbon dioxide gas permeation per day (1 atm, 23℃
The calculation was performed by subtracting the carbon dioxide volume (CC) converted to the internal pressure (atm) immediately after filling the dry ice.

The number of test bottles was three for each sample, and the average value was calculated.

The internal volume (excluding the volume of the spout) V of the stretched bottle can be measured by filling the portion of the bottle excluding the spout with water.

The inner surface area of the stretched bottle (excluding the inner surface of the spout part) S is determined by dividing the bottle, detecting the inner surface shape with a coordinate measuring machine, dividing it into microscopic parts, and integrating the area of the microscopic parts. It can be measured by the splitting method. Note that if the stretched bottle has a simple shape, the inner surface area can be calculated as an approximate value by assuming that the body of the bottle is a cylinder and the lower and upper parts of the bottle are hemispheres. can.

In addition, the average thickness t (mm) of the center part of the body part excluding the spout of the bottle is determined by dividing the center part of the bottle into four parts and measuring the thickness (in mm) at four target positions. It can be found by

For reference, the gas barrier property with thickness correction added is evaluated by the carbon dioxide gas permeability coefficient Pd (Co,,) and the oxygen gas permeability coefficient Pd (02),
Using a carbon dioxide permeation tester model PERMATRAC-IV manufactured by MODERN CONTROL (USA), PE
The carbon dioxide permeability coefficient Pd (Co
2) was measured, and the OXTR
The oxygen gas permeability coefficient Pd(02) of a sample consisting of a section at the center of the body of a 300-400 μm thick bowl was measured by the AN method under conditions of a temperature of 23° C. and a relative humidity of 0%.

In the polyethylene naphthalate resin bottle according to the present invention, the stretch index defined as below is 130 cm or more, preferably 1-40 to 220 cm.
It is desirable that the film be highly stretched to 150 to 200 am, more preferably 150 to 200 am.

Internal volume of stretched bottle (excluding spout ()1 stretch index =
×Inner volume of unstretched preform (excluding the spout) fInner volume of stretched bottle (
The internal volume of the stretched bottle as shown above (excluding the volume of the spout)
Specifically, the volume (excluding the volume of the spout part) is the internal volume of the bottle 1 below the Zapo I-ring 8, and more specifically,
It means the internal volume of the ball below the virtual straight line 9.

In addition, the internal volume of the unstretched preform (excluding the spout) is
Specifically, it is the internal volume below the support 1 and ring 8 of the preform 7, and more specifically, it means the internal volume of the bowl 1 below the virtual straight line 9.

Furthermore, the inner surface area of the stretched bottle 1 (excluding the cap volume) is specifically the inner surface area of the stretched bottle below the support 1 ring 8 of the bottle 1. means the inner surface area of the ball below the virtual straight line 9.

In such a bottle according to the present invention, the wall thickness at the body is:
Same as conventionally known bottles, usually 0.1 to 0.5r
nm is preferably about 0.2 to 0.4 mm.

Next, a method for manufacturing a bottle according to the present invention will be explained.

First, a preform is manufactured from the polyethylene naphthalene-1 resin as described above, and this preform can be manufactured by a conventionally known method.

Such a preform is manufactured by a conventionally known method, but in the present invention, the stretched portion of the preform is stretched to a higher degree than in the conventionally known method, so the length of the preform is longer than that of the conventional preform. It is desirable that it be molded shorter than the reform.

Furthermore, if necessary, the diameter of the preform can also be made smaller than that of conventional preforms.

In the present invention, a bottle is manufactured by blow molding the bottle forming preform as described above.

At this time, the stretching index of the obtained bottle defined as above is 130 am or more, preferably 14
0 to 220 Cm, more preferably 150
Blow molding to a thickness of ~200 cm.

In addition, the temperature during flow molding of BRIFORM is 110 ~]
50°C, preferably 120°C to 50°C, more preferably 125°C to 145°C.

The polyethylene naphthalate resin thus obtained is made of polyethylene naphthalate resin and has a stretching index of 1.
Bottles that have been highly stretched to a length of 30 cm or more have extremely excellent gas barrier properties.For example, compared to conventionally commercially available polyethylene terephthalate bottles, their gas barrier properties against carbon dioxide (CO2) are approximately It is improved by 20 times, and the gas barrier property against oxygen (02) is also improved by about 7 times. Furthermore, compared to a bottle made of polyethylene naphthalate resin that has been stretched to a stretching index of about 95 cm as defined herein, the bottle according to the present invention has a lower gas barrier property against carbon dioxide (Co.). It is improved by about 3 times, and the gas barrier property against oxygen (02) is also dramatically improved by about 2 times.

In addition, the bottle according to the present invention has heat resistance (Tg is about 120
℃), as well as transparency and mechanical strength.

Effects of the Invention The polyolefin according to the present invention has dramatically improved gas barrier properties against oxygen or carbon dioxide, and is also excellent in heat resistance, transparency, and mechanical strength.

Example] Polyethylene naphthalene-1 resin having the following physical properties obtained from 2,6-dinaphthalene dicarboxylic acid and ethylene glycol was molded using a molding machine M-10 manufactured by Meiki Seisakusho ■.
A preform for forming a bottle was obtained by molding with OA. The molding temperature at this time was 270 to 290°C.

Polyethylene naphthalene 1/Resin: Intrinsic viscosity [η: Q. 6 dρ/g Elevated temperature crystallization temperature (TC): 180°C Next, the preform obtained as above was CORP
A biaxially stretched bottle was obtained by molding using an LB-01 molding machine manufactured by OPLAST. The stretching temperature at this time was 130 to 140°C.

The internal volume of the unstretched preform (excluding the spout) is 194
and the inner volume of the obtained stretched bottle (excluding the spout)
was 1469-.

The inner surface area of the stretched bottle (excluding the inner surface of the spout) was 678C.

Therefore, the stretch index is calculated as follows.

Stretching index = = 1 6
8× ]9 4 6 cm Carbon dioxide permeable Pc as described in the specification
, carbon dioxide gas permeability coefficient Pd (CO2) and oxygen gas permeability coefficient Pd (02) were determined as /i1.

The results are shown in Table 1.

Transparency was also determined by cutting the body of the bottle and measuring Haysmeter NDH-2 (L D
The haze value of the test piece was measured three times using a method according to ASTM D 1.003, and the average value was used for evaluation.

The results are shown in Table 1.

Cut out the center part of the body of the hole obtained in this way, and cut 5 places at approximately equal intervals from the center part to
A line interference intensity distribution curve was determined. At each location, the β angle is 0''±20° or 180°±20°, and 90''±20' or 270° and 20°. . were measured to determine 1/I and 19o/1b, respectively.

Ob The results are shown in Table 2.

Note that φ is the degree to which the β angle at which the maximum value is observed deviates from 0°. The deviation from 90° is expressed as φ9o, and the results are shown in Table 2.
It is also shown in .

The X-ray interference intensity distribution curve and X-ray pole figure at illll fixed point 3 in Table 2 are as shown in FIGS. 2 and 3 above.

Comparative Example] In Example 1, the internal volume excluding the spout was 33.4 ct
The procedure was the same as in Example] except that the unstretched preform A was used and the stretching index of the bottle was set to 95 cm.

The results are shown in Table 1.

Further, the X-ray interference intensity distribution curve was measured in the same manner as in Example 1, and the results were as follows: ■/■, ■/1, φ. O b
90b and φ9o were determined.

The results are shown in Table 3.

Table 1 table Numbers 1 to 5 next to the title indicate the measurement locations.

table No local maximum

[Brief explanation of the drawing]

FIG. 1 is a schematic explanatory diagram of a bottle, and FIG. 2 is an X-ray interference intensity distribution curve on the circumference of the center part of the body of the polyethylene naphthalene bottle 1 according to the present invention. FIG. 3 is an X-ray pole figure on the periphery of the central part of the body of the polyethylene naphthalate bottle according to the present invention. 1... Bottle 2... Spout part 3... Upper shoulder part 4... Body part 5... Lower shoulder part 6... Bottom part

Claims (1)

[Claims] 1) Made of polyethylene naphthalate resin, the β angle is 0° with at least 80% probability in the X-ray interference intensity distribution curve at multiple points around the center of the bottle body.
A stretched bottle made of polyethylene naphthalate resin, characterized in that maximum values are observed in both the ranges of ±20° and β angle of 90°±20°.