JPS5820636A - Plastic vessel - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a plastic container, and more particularly, to a plastic container that has a high-grade carnivorous appearance, feels good when touched, and has excellent heat shrinkage resistance and mechanical strength. Regarding.

Plastic containers, e.g. PVC.

Polycarbonate, polystyrene, poly7 clear, +1 R2)! BACKGROUND ART Containers made of thermoplastic resins such as polyester, polyester, and polyolefin resins are widely used as containers for foods, beverages, cosmetics, medicines, and the like. In particular, stretch polyester resin containers, typically made of polyethylene terephthalate, are transparent.

Carbonated beverages due to their excellent gas permeability, water vapor permeability, safety, and mechanical properties.

Edible oils, sauces, mustard oil, Kl flavorings, pharmaceuticals.

In recent years, their use as containers for alcoholic beverages, etc., has been expanded dramatically.

However, such transparent containers are unsatisfactory in terms of a more luxurious appearance than the container.

Examples of ways to make the appearance of the container high-class include adding fine irregularities to the outer surface of the container to give it a so-called frosted glass appearance, as seen in glass containers, or adding many striped patterns to the outer surface. There are various methods of imparting a similar appearance to plastic containers, and a commonly used method of imparting a similar appearance to a plastic container is to process it so that it exhibits a pattern similar to that of a blow molding mold. However, the method of applying such processing to the mold K and transferring it has the disadvantage that the pattern is transferred only to the outer surface of the container, resulting in a lack of depth in appearance, and that air is formed between the mold surface and the outer surface of the container during molding. The pattern of the mold may not be fully transferred to the container because it cannot be removed sufficiently, the container may stick to the surface of the mold (this may cause problems during molding, and the fine carvings of the mold may The disadvantage is that solids in a low polymer state accumulate in the container and are transferred to the outer surface of the container, resulting in defects in appearance.

In addition, as a method for producing a frosted glass-like container using polyester resin, a polyester container or an intermediate material such as a bottomed parison is sandblasted to roughen its surface, or an intermediate material such as a parison is treated with a solvent. A method of biaxially orientation after crystallization has been proposed. However, these intermediate processing or post-processing
Since chemical or physical changes are performed during or after container manufacturing, productivity is low and it is difficult to always provide a ground glass finish under constant conditions.

The main method is to use a method in which a bottomed parison, which is an intermediate material, is crystallized by heating and then blow molded, or a bottomed parison is crystallized by slow cooling during injection molding.
Blow molding methods have been proposed, but it is difficult to control the crystallization of bottomed parisons, and parisons with too much crystallization can be blown into the shape of the blow mold. It has the disadvantage that it cannot be stretched and cannot be completely shaped.

Furthermore, attempts have been made to add K115 inorganic inert particles such as talc or clay to a polyester resin and to obtain a ground glass-like container by blow molding. The resulting container tends to have a milky color, and the particles added from outside act as a so-called crystallization nucleating agent that promotes the crystallization of polyester. If the injection port part becomes white during injection molding, and the injection port part becomes the bottom of the container, the drop impact strength of the container may be significantly reduced or the texture may become swollen. However, a container with a satisfactory ground glass appearance has not yet been obtained by adding inert particles.

The inventors of the present invention have conducted extensive studies in order to obtain a container that has improved heat shrinkage resistance and mechanical strength, as well as a ground-glass appearance and an excellent feel when touched, compared to containers obtained by conventional molding. As a result, by stretching a thermoplastic resin containing glass particles of a specific shape in a specific ratio, it was possible to create a material with a high-quality appearance, excellent heat shrinkage resistance, high buckling strength, pressure deformation resistance, It was discovered that a plastic container with excellent mechanical strength such as resistance to deformation under reduced pressure can be obtained, and the present invention was achieved.

That is, the present invention has an average lume of 1 μm or less and a particle size of 1 μm.
01 to 3 oom plate glass particles with a mesh size of 0 mesh or less
This is a plastic container made of a thermoplastic resin containing H, and having a portion stretched in at least one direction.

The thermoplastic IS4 resin referred to in the present invention refers to blow molding.

It is a thermoplastic resin that can be molded into a container by a molding method that involves stretching, such as vacuum forming or pressure forming. Preferred thermoplastic resins are shown in Table 1. Among these, those having a light transmittance of 70 inches or more are more preferable because they form a good ground-glass appearance, and polyester resins are particularly preferable because the effects of the present invention are significantly exhibited.

-1 Note) 1) A: Good transparency, B: Slightly cloudy)) C
: Translucent, D = Opaque 2) Measured using ASTM D-1003ic Among the above thermoplastic resins, a particularly preferred polyester resin is mainly polyethylene terephthalate obtained by the reaction of terephthalic acid or its lower alkyl ester with ethylene glycol. However, a part of the terephthalic acid component (usually 20 mole or more "'F'") can be added to, for example, inphthalic acid, naphthalene dicarboxylic acid, diphenyldicarphonic acid, diphenoxyethanedicarboxylic acid, diphenyl ether dicarboxylic acid, Schiff: Aromatic dicarboxylic acids such as sulfonic acid; alicyclic dicarboxylic acids such as hexahydroterephthalic acid, hexahydroterephthalic acid, etc.; aliphatic dicarboxylic acids such as 7-dipic acid, sepatic acid, 7-gelaic acid, etc. acid; p-β-human p-oxyethoxybenzoic acid; one or more other bifunctional carboxylic acids of oxy-deactivation such as ε-ogicicaproic acid, etc., and/or a part of the ethylene glycol component (usually 20 molar or less)
For example triethylene glycol, tetramethylene glycol, hexamethylene glycol, decamethylene glycol, neopentyl glycol, diethylene glycol, triethylene glycol.

1,1-cyclohexane dimethylol, 1,4-cyclohexane dimethylol, 2,2-bis(4'β-hydroxyethoxyphenyl)propane.

I! of polyfunctional compounds such as other glycols such as bis(4'-β-human p-xyethoxyphenyl)sulfonic acid and their functional derivatives. It may be substituted on ll17 and copolymerized.

Among such polyester resins, a homopolymer of polyethylene terephthalate is most preferable, but the polyethylene terephthalate has an intrinsic viscosity of 0.5 or more, more preferably 0.
．． It is preferable that it is 60 or more. Furthermore, the softening point of polyethylene terephthalate is 220°C to 270°C.
"C" is preferred, particularly 250°C to 265°C. It is desirable that other polyester resins have physical properties similar to those described above. Polynisful resins are also known to those with ordinary knowledge in this field. It may be manufactured by any method.

The plate-shaped glass particles used in the present invention have an average thickness of IOJ or less and a particle size of IO mesh or less. The average thickness is 10μ and the particle size is 10
A material larger than a mesh is not preferable because it gives a rough feel upon contact. There is no particular lower limit to the particle size, but if the grain size becomes too fine, the appearance will become cloudy, so it is preferable that the length of the plate-like flat part is at least 5 times the thickness.

The proportion of glass particles contained in the thermoplastic resin is 0.1
~311chi range four. If this ratio is less than 0.1%, the crystalline appearance that is a feature of the present invention will be poor, and if it is more than 30% by weight, it will be difficult to form a container by stretching.

The preferred ratio of glass and granules is the molding force θ of the container.

Although it varies depending on the stretching ratio, stretching temperature, topographical conditions, etc., for example, when polyethylene terephthalate resin is molded by biaxial stretching blow molding, the number is 02 to 10 times, and # is 0.
When the range is 6 to 5 times, the appearance of the container is good <1. It is preferable because the molding operation is easy.

An example of the plastic container of the present invention is a bottle.

An example is a container obtained by a molding method that involves stretching, such as kelp. Stretching during the molding process produces the textured appearance that is a feature of the present invention; however, such an appearance cannot be expected if the container is simply formed by injection molding.

A method for obtaining a container having the features of the present invention, for example, in the case of a bottle, a conventional injection blow molding method.

Extrusion blow molding and biaxial stretch blow molding are commonly used. In the case of injection blow molding, a closed-ended parison is formed by direct injection molding of an expandable geometrical shape, which is then transferred into a bottle mold and blow-expanded. At this time, when injection molding the parison, it is preferable to cool the core mold and the injection mold with a refrigerant such as water cooling or air cooling. In addition, when molding a container by extrusion blow molding, first extrude heated and melted thermoplastic resin into a pipe shape, and then cut the pipe-shaped extrudate into a desired length and cut out the bottom to create a bottomed container. A parison is made, the parison is placed in a mold having the shape of the desired container, and a compressed fluid, such as compressed air, is blown into the parison to expand it to the shape of the container.

In addition, when molding a container using thermoplastic resin by knee-axis orientation blow molding, first the thermoplastic resin is heated and melted using an injection molding machine to a temperature higher than the melting point of the polymer, and then injected into a preform mold and cooled. The parison is then reheated to a temperature within a range that allows it to be stretched, transferred into a mold having the desired container shape, stretched in the axial direction by a stretching rond, and compressed. A fluid such as compressed air is blown into the container to expand it to the shape of the container.

When the bottomed parison is stretched or blow-surprised, the stretching ratio of the body of the bottle is at least 1.2 times, preferably at least 2 times, in terms of area magnification. or.

Methods for obtaining containers such as pots include, for example, air pressure forming,
Methods such as vacuum forming are applied.

When a container containing plate-shaped glass particles is manufactured by the above-mentioned blow molding, pressure forming, vacuum forming, etc., the container may be made of a single layer of thermoplastic resin layer containing the plate-shaped glass particles. However, depending on the application, it may have a multilayer structure with the same resin or with other resins.

Dyes, pigments, ultraviolet absorbers,
Do inorganic inert particles, stabilizers, etc. impair the purpose of the invention? f
It can be added within a certain range.

In the present invention, any method can be selected as the method for adding the plate glass particles. For example, a method in which it is added when polymerizing a thermoplastic resin, a method in which a master pellet containing a high concentration of plate glass particles is separately manufactured (and then blended with additive-free pellets during molding), or a method in which it is added by blending it with additive-free pellets during molding. There is a method of directly molding plate glass particles by sprinkling them onto a pellet, but in order to tightly incorporate the plate glass particles into the thermoplastic resin, there is a method of adding the thermoplastic resin before polymerization. Alternatively, a method using master pellets is preferable.If the plate-like glass particles are poorly dispersed in the resin, not only will the commercial value of the hollow container be significantly impaired, but the effect of improving heat shrinkage resistance and mechanical strength will not be achieved. No. 9 The ground glass container produced by the method of the present invention can be produced by simply incorporating sheet glass particles into the thermoplastic resin material, and does not require any post-processing such as sandblasting, and is economically superior. Not only that, but it also has the advantage of being able to be manufactured under constant conditions and having excellent reproducibility.Additionally, the addition of plate glass particles impairs the original excellent properties of thermoplastic resin. It maintains excellent gas permeation resistance and mechanical strength.Furthermore, the chestnut glass-like container and the bottomed parison, which is an intermediate material, have excellent slipperiness, so they can be easily used during the manufacturing process and on the container. The productivity during filling the contents will be significantly reduced by several pieces.

The plastic containers thus obtained have excellent heat shrinkage resistance and mechanical strength, and are useful as containers for various industrial applications, and the ground glass containers with M dynamic appearance are particularly useful for cosmetics.

Useful as a container for alcoholic beverages.

The present invention will be described in detail with reference to examples below. However, the present invention is not limited to the following examples unless it deviates from the gist of the invention. The measurement method is shown below. Hot water shrinkage 2 After filling a bottle with hot water at 80°C, the bottle was tightly stoppered and left to stand. The bottle was opened for 24 hours and the internal volume of the bottle was measured. The shrinkage rate was determined by the formula below. Ta.

Shrinkage rate -1-1 x 100 (chi) v.

Zaso strong tweet: Toyo #l vessel TENSILON/UTM-1
11-500, an empty bottle was charged with a normal force of 1 m1 at a head speed of 5 m/min, and the load when the bottle deformed was calculated.

Pressure resistance strength: Tok by a water pressure machine in a bottle filled with water
Water was applied at a speed of 1 g/clG/min, and the pressure at which the bottle burst was determined.

Light transmittance: Measured using a light beam transmittance measuring device (
However, the thickness is measured at 0.3 m/rn) JIS K
-,6714ffi, iru. σ) Light transmittance is 20
If you take values from 1 to 3, a ground glass effect will appear.

Examples 1 to 3 and Comparative Example 1 A pellet of polyethylene terenoterephthalate with an intrinsic viscosity of 070 was added to glass flakes having the thickness (μ) and particle size (mensch) shown in Table 2 below. Using an injection molding machine with a temperature of 280℃, the length is 49y, length + 76rn/yr,
An inner cylindrical bottomed parison with a wall thickness of 3.5 m/m was molded. At this time, the preform mold was cooled to 10° C. with cold water. The parison is then heated to an internal temperature of 90-10
After reheating to 5℃, the biaxial stretching process is carried out.
A bottle with an internal volume of 11 was obtained, with a field height of 270 m/rn + a body diameter of 80 to 90 m/@, and an average wall thickness of the body of o3s m/1n. The shrinkage rate, buckling strength, and pressure resistance of the obtained bottle when filled with 80°C hot water are shown in 6-2.

From Ki-2, a container I-1 made of polynisdel containing 0.5 or more layers of glass flakes has higher hot water shrinkage rate, buckling strength, and pressure resistance than a container that does not contain glass flakes. It has excellent mechanical strength such as
It can be seen that the reforming effect of the present invention is unique.

Claims (1)

[Scope of Claims] 1. Made of a thermoplastic resin containing 0.1 to 30% by weight of plate glass particles having an average thickness of 1Oμ or less and a particle size of 10 mesh or less, and stretched in at least one direction. A plastic container with a part that is 2. The plastic container according to claim 1, wherein the thermoplastic resin is polyester containing ethylene terephthalate as a main component.