JPS5987132A - Blow molded container - Google Patents

Abstract

PURPOSE:To improve the bonding strength at the pinched-off section and the color tone, by forming a single layer or the like that comprises a polyamide layer containing an alkali metal salt or alkali earth metal salt of hypophosphorous acid, phosphorous acid or phosphoric acid. CONSTITUTION:A polyamide containing 0.01-5wt% alkali metal salt or alkali earth metal salt of hypophosphorous acid, phosphorous acid or phosphoric acid is prepared. Then a blow molded container is molded by using the single layer blow molding machine or multi-layer blow molding machine. A polyethylene, polypropylene, ethylene/vinyl acetate copolymer, etc. can be used for the resin layer forming the container together with the polyamide layer in the multi-layer blow molded container. As a resin for bonding the resin layer to the polyamide layer can be mentioned an adherent polyolefin resin or the like.

Description

[Detailed description of the invention] The present invention relates to blow molded containers.

In detail, the adhesive strength at the pinch-off part is high, and the color 61
J relates to a good blow-molded container.

BACKGROUND ART Recently, multilayer blow-molded containers having a polyamide layer or a polyamide layer as an inner layer have been used in a wide variety of applications.

In blow-molded containers, the pinch-off part is easily destroyed or peeled off, so it is an important issue to improve the adhesive strength of the pinch-off part, and for this purpose,
For example, one constructed of a polyamide layer containing copper chloride or a derivative thereof has been proposed (Japanese Patent Publication No. S7-U57Q).

However, blow-molded containers made of polyamide containing copper halides take on a brown to blue tone when used with copper halides that provide sufficient pinch-off bond strength, especially when iodine is used. When used as a container, the color is brownish when dried, but when it comes into contact with water or alcohol, the color changes to a blueish color, making it unsatisfactory and durable as a container. Furthermore, if the Ryo-O 1 polyamide used as the material is colored, even if you try to color it with dyes and pigments, the color will be dull and brightly colored products will not be as good.

The inventors of the present invention have conducted extensive research in order to obtain a blow-molded container with excellent adhesive strength at the pinch-off part and good color tone, and have found that when using polyamide containing a special compound, the effect is sufficiently satisfactory. The present invention was completed based on the knowledge that the present invention can be obtained.

That is, the present invention aims to provide a blow-molded container of great industrial value, and its gist is to provide a blow-molded container with hypophosphorous acid, phosphorous acid, or phosphoric acid in alkali gold or alkaline earth metal coffins. It is a single-layer blow-molded container composed of a salt-containing polyamide layer or a multilayer blow-molded container having the polyamide layer as an inner layer.

The present invention will be explained in detail below.

The polyamide used in the polyamide layer of the present invention includes:
Lactams such as ε-cagproctam, polymers such as ε-amino acids such as amitsukaglonic acid, diamines such as hexamethylene diamine, nonamethylene diamine, metaxylylene diamine, and adipic acid, sepatic acid, dodecanedicarboxylic acid, and terephthalic acid. Polymers obtained by polycondensing dicarboxylic acids such as acid, isophthalic acid, and cyclohexanedicarboxylic acid, and polymers obtained by copolymerizing the above raw materials to produce 1q. Typical examples include nylon. 6, //, /2, Otsu, Otsu, Otsu, /θ,
Examples include 4T, A/i Otsu, and 6/6T.

These polyamides may be manufactured in a special manner and may also be
Other resins, such as ethylene/vinyl acetate copolymer, ethylene/acrylic acid ester copolymer, ionomer resin, etc., as long as they do not impair the gas barrier properties of the polyamide layer.
A polyolefin resin with improved adhesion such as a modified ethylene copolymer obtained by graft polymerizing α, β-unsaturated carboxylic acid or the like to ethylene and monomer may be blended.

The hypophosphites, phosphites and phosphates used in the present invention include hypophosphites, phosphates of all alkali metals such as sodium, potassium and alkaline earths such as calcium, magnesium and barium. Phosphates, acidic phosphites, phosphoric acid salts, acidic phosphates, pyrophosphates, polyphosphates, etc. can be used, but it is particularly preferable to use sodium hypophosphite, hypophosphorous potassium, and the like.

The above hypophosphorous 1 Kana, phosphite still contains phosphate 'fTM
is about 0.07 to 11%, preferably O,OS~/wt% based on the polyamide layer. If the amount is too small, the effects of the present invention cannot be expected. On the other hand, if the amount is too large, the molecular structure of the polyamide will be lowered during molding, resulting in lower viscosity, making blow molding difficult, and lowering the strength of the product, which is undesirable.

As a method for incorporating the hypophosphite, phosphite, or phosphate into the polyamide, a method such as triblend or kneading the triblend using an extruder or the like can be adopted.

At this time, it is preferable to include a lubricant such as stearic acid, calcium stearate, magnesium stearate, ethylene bisstearamide, waxes, urea wire conductors, etc. because this facilitates the mixing operation. The amount of the lubricant to be used is preferably less than S weight % based on the above hypophosphite, phosphite, or phosphate, and preferably about the same amount as the amount of freezing. If the amount is too large, the adhesive strength between the polyamide and other resins will be reduced in the case of multilayer blow molding.

Also, to uniformly blend the additives, an emulsion such as polyethylene glycol or its P'N4 form, mineral oil, silicone oil, etc. may be used.

The blow molded container of the present invention is molded using a single layer blow molding machine or a multilayer blow molding machine according to a known conventional method. In a multilayer blow molded container, the resin layer that forms the container together with the polyamide layer may include polyethylene,
Polypropylene, ethylene/vinyl acetate copolymer, etc. may be mentioned, and the adhesive polyolefin resin described above may be used as the adhesive layer resin used for adhesion between these resin layers and the polyamide layer.

The blow-molded container of the present invention has a high degree of adhesive strength at the pinch-off part, so it can be used for everything from large containers such as gasoline tanks to small containers such as containers for food and cosmetics. It can be suitably used. In addition, since the color tone is good, the appearance of the content C1 does not look JJi, and it is suitable as a colored container.

Hereinafter, the present invention will be specifically explained with reference to Examples, but the present invention is not limited to the following Examples unless the gist of the present invention is exceeded.

In addition, the adhesive strength of the pinch-off part was determined by filling a test container with water and placing the pinch-off part on the bottom surface.
The container was dropped from a height of 7 m so that the pinch-off part hit the top of the ball, and the number of broken containers out of 10 test containers was expressed as 1-out of 10 containers.

However, the color tone still remains after a week after filling with water, cutting the body of the test container, and using a color difference meter (manufactured by Suga Test Instruments, digital colorimeter AND-01-I Model 2). The a and b values were measured using (7). A large negative value of the a value indicates that the green color has been present, and a large positive value of the b value indicates that the yellow color has been present. .

Examples/~S and Comparative Example 7~a Relative viscosity IIIL, g5. ．． Dry blend hypochlorite, phosphite, or phosphate shown in Table 1 on the pellet of nylon Otsu (made by Mitsubishi Kasei Kogyo Sen Co., Ltd., registered trademark, Tsubamitsudo 10170) in No. 2, and add this to the J1 layer. Blow molding cherry blossoms (Japanese copper Tzu1 (Tase, Nt33B-8 & (IIJ type), resin temperature 1i, 2A 0℃, former 1out M, 20
The parison was extruded at Kg/hr.

By putting this parison in a mold and blowing it with air, the thickness /IW+ is 4iW1! A container of r 00 me was molded.

The adhesive strength and color tone of the pinch-off portion of the container were as shown in Table 1 for sweat distribution.

For comparison, the results when no additive was added and when copper iodide was added are also shown.

Next Mu ↑ Tari 6 The outer layer is high-density polyethylene (manufactured by Sanhen Seiko Shi0, registered trademark, Tsubachik Bi'-00,2), and the middle layer is a modified ethylene copolymer made by graft polymerizing maleic anhydride to low-density polyethylene. Combining (manufactured by Mitsubishi Kasei Torai@, registered trademark, Tsubachik PA, l-○L), the inner layer is the same nylon used in Examples / with 0.0% sodium hypophosphite. , Z]
The rectangular-chu dry blend was blow-molded using a 3-layer blow-molded rock (manufactured by Plako & Song), and the outer layer/intermediate layer/inner layer = 300 fi / 30 tt /' /
A 3-layer container of 00 μm and 500 me was manufactured.

The adhesive strength IW of the pinch-off part of this three-layer container is θ//
Out of 0, the a value is "-8, 711. The b value is 3.
0. :1. I failed.

Applicant: Mitsubishi Kasei Kamiyo 4'1, Shikikai Toshiyoshi, Attorney: Patent Attorney Head - ((only 7 people)

Claims (1)

[Claims] (1) A single-layer container made of a polyamide layer on which hypophosphorous acid, phosphorous acid, or an alkali metal or alkaline earth gold maple salt of phosphoric acid is mounted, or a multilayer blow-molded container with the polyamide layer as the inner layer F4. . (Claim No. 2, wherein the content of phosphoric acid, phosphorous acid, or alkali metal salt or alkaline earth metal salt of phosphoric acid is 0.0/~5-H-#:% with respect to the polyamide layer) Blow molded container 0 described in section 1)