JPS60203421A - Manufacture of container having flexible wall surface - Google Patents

Abstract

PURPOSE:To obtain a container having the wall surface which is superior in flexibility and is provided with monolithic structure which is superior in mechanical structure, by molding the titled container by making soft plastics and hard plastics correspond to a flexible wall surface cavity and a monolithic structural component molding cavity respectively. CONSTITUTION:Soft plastics 9A and hard plastics 9B are arranged so as to correspond with a flexible wall surface molding cavity 11A and a monolithic structural component molding cavity 11B respectively. In addition to the above, an extrusion direction of a parison 9 and the whole circumferences on both the sides meeting at right angles with the extrusion direction are placed between pinch off parts 12 of a mold, and positioning of the parison 9 is performed along with performance of compression molding of a reinforcing rib. Then the parison 9 is expanded in a mold 10 by introducing pressure fluid such as compressed air within the parison 9 and the parison 9 is molded into a shape of a cavity 11. After cooling of a molded article, the mold 10 is opened and the molded article is obtained by removing surplus burrs generated on the circumference of the molded article.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a container having a flexible wall surface and provided with structural members such as a mouth and a bracket.

[Prior art]

A container having a flexible wall surface and provided with structural members such as a spout and a bracket is used as a cleaning liquid tank for an automobile window cleaning device, a parenteral drug solution container for medical use, and the like. For example, as shown in Japanese Utility Model Publication No. 47-6010, a flexible wall surface is formed from two soft plastic sheets, an injection port and a bracket are formed from semi-hard plastic sheets, and the A manufacturing method in which a bag body is formed by joining by high-frequency welding, and a manufacturing method in which a flexible wall surface, a drain port, and a handle are integrally blow-molded as disclosed in Japanese Patent Publication No. 53-4474 are known.

[Problem that the invention seeks to solve]

The manufacturing method disclosed in Utility Model Publication No. 47-6010 includes the steps of molding two soft plastic sheets;
It requires a step of molding a semi-rigid plastic sheet having an injection port and a bracket, and a step of joining and assembling these sheet members by high-frequency welding, making the manufacturing process multi-step and complicated. On the other hand,
The manufacturing method disclosed in Publication No. 3-4474 has the advantage of being able to manufacture containers using only the blow molding process, but on the other hand, the flexible wall surface, the υE liquid port, and the handle are made of the same plastic material. Because of the structure, the drain port and handle must also be flexible, and for example, when attaching a separate tube to the drain port, it is difficult to attach it tightly. The problem with achieving strength is that the flexible wall loses its desired flexibility.

[Summary of the invention]

The present invention is based on blow molding, and is intended to solve the above-mentioned problems using a novel method that has not been seen before.

That is, the present invention melts and kneads a soft plastic and a hard plastic in separate extruders, and then joins the plastics together in an extrusion die to form a plasticized cylinder or two sheets. The parison is extruded from an extrusion die as a parison, and when the parison is held in a split mold that has a cavity for molding a flexible wall surface and a cavity for molding an integral structural member such as a mouth part, the soft plastic is flexible. a rigid plastic is placed in the flexible wall molding cavity so as to correspond to the integral structural member molding cavity, and then a pressurized fluid is introduced into the parison to expand the ballison in the mold and mold it into the shape of the cavity.
A method of manufacturing a container having a flexible wall surface, in which a container having a wall surface with excellent flexibility and integral structural members such as a spout, a bracket, and a handle with excellent mechanical strength is integrated by blow molding. In addition, when holding the parison in the mold, if both sides of the parison perpendicular to the extrusion direction are held between the pinch-off parts of the mold, the parison is well positioned and expanded within the cavity. Therefore, it is possible to manufacture containers with respective characteristics at desired locations.

In the present invention, the materials and combinations of thermoplastic plastics used for the flexible wall surface and the integral structural member of the container can be arbitrarily selected depending on the manner in which the container is used. Thermoplastics include low density polyethylene, medium density polyethylene,
Ethylene-vinyl acetate copolymer (vinyl acetate content 10
% or more), ionomers, soft polyvinyl chloride, ethylene-propylene elastomers, styrene-butadiene elastomers, polyester elastomers, polyamide elastomers, and blends thereof, whose tensile modulus (ASTM-D-638) ES is In order to obtain sufficient flexibility, it is less than 2 x 10"kg/cm", preferably less than 1.5 x 103 kg/cm". On the other hand, as a hard thermoplastic used for the integral structural member, medium density polyethylene lz7, High-density polyethylene, ethylene-vinyl acetate copolymer (vinyl acetate content less than 10%), ionomer, rigid vinyl chloride, polyester, polyurethane, polyamide, and elastomers and blends thereof, whose tensile modulus EH is In order to obtain the shape retention property, it is 2X103 kg/cm" or more, preferably 2.5X10"kg/cm" or more.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS As an embodiment of the present invention, a method for manufacturing a cleaning liquid tank for an automobile window cleaning device will be described with reference to FIGS. 1 to 4.

In the figure, 1 is an automobile window cleaning liquid tank obtained by the manufacturing method of the present invention, A is a flexible wall made of soft thermoplastic, and B is an integral structural member made of hard thermoplastic.

The integral structure member B includes a cleaning liquid inlet 2, a shape retaining frame 3, and a cleaning liquid spout 4 to which a spouting pipe 8 is attached.
, a pump mounting recess 5 for supplying cleaning liquid from inside the tank to the automobile window, and a mounting bracket 6 for the tank itself are formed. 7 is a reinforcing rib located on the blow molding special parting line. The flexible wall surface A is deformed in the direction of expansion and contraction depending on the amount of cleaning liquid, and the overall shape of the tank 1 itself is maintained by the shape-retaining frames 3 on both sides. Hereinafter, the manufacturing method of the tank 1 shown in FIG. 1 will be explained based on FIG. 2 and FIG. A flexible wall molding cavity IIA and an integral structural member molding cavity IIB are formed in the mold 10, and the integral structural member molding cavity IIB has an injection port,
Shape retaining frame, spout, pump mounting recess, bracket cavity, 112B, 113B, 114B, 115B
116B is formed and a flexible wall molded cavity I
On the outer periphery of the IA and integral structural member molding cavity 11B,
A compression portion 117 for forming reinforcing ribs is formed. first,
Melt and knead soft plastic and hard plastic in separate extruders, and then transfer the above plastics to an extrusion die.
(not shown), and mold 1 as shown in FIG.
The soft plastic 9A and the hard plastic 9B are extruded as a cylindrical parison 9 that is symmetrical with respect to the parting line PL of 0 so that the plastics in the opposing parts with the PL as the boundary are of the same quality, and are extruded into a split-type mold 10.
is closed to hold parison 9. At this time, the soft plastic 9A is placed in the flexible wall molding cavity IIA, and the hard plastic 9B is placed in the integral structural member molding cavity 1.
1B, and Parishion 9.
The extrusion direction and the entire periphery of both sides perpendicular to the extrusion direction are clamped by the mold pinch-off parts 12, and the reinforcing ribs 7 are compressed and molded, and the position of the parison 9 is set. Then, a pressure fluid such as compressed air is introduced into the parison 9 to expand the parison 9 within the mold 10 and mold it into the shape of the cavity 11. Then, after cooling the molded product, the mold 10
The molded product is opened and excess cast burrs generated around the molded product are removed to obtain a cleaning liquid tank 1 for an automobile window cleaning device as shown in FIG.

FIG. 5 shows a medical parenteral drug solution container 13, which is the other side of the container obtained by the manufacturing method of the present invention, and is composed of a flexible wall surface A and an integral structural member B. A reinforcing rib 14 located on the blow molding special parting line and a mounting hole 15 for the container itself are formed on the flexible wall surface A, and an inlet 16, an outlet 17 and a shape are formed on the integral structure +J'B. A wall 18 is formed which can hold and be curved.

〔Effect of the invention〕

As mentioned above, the manufacturing method invented by Zero uses blow molding to create a container that has an excellent wall surface with excellent flexibility and is equipped with integrated structural members such as a spout, a bracket, and a handle that have excellent mechanical strength. It can be easily manufactured, and containers with respective characteristics at desired locations can be manufactured without requiring multiple steps.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a cleaning liquid tank of an automobile window cleaning device obtained by the manufacturing method according to the present invention, FIG. 3 is a side view of the mold seen from the parting line direction, FIG. 4 is a cross sectional view of the mold, and FIG. 5 is a cross-sectional view of the container obtained by the manufacturing method according to the present invention. FIG. 2 is a perspective view of a parenteral drug solution container for medical use. 1: Cleaning liquid tank 2: Inlet 3: Shape retaining frame 4: Outlet A: Flexible wall B integral structural member 9: Parison 10: Mold patent applicant Kyoraku Co., Ltd.

Claims (2)

[Claims] (1) A soft plastic and a hard plastic are melted and kneaded in separate extruders, and the above plastics are joined in an extrusion die to form a plasticized cylinder or two sheet-like parison. Extruded from an extrusion die,
When holding the Balisun in a split-type mold that has a flexible wall molding cavity and an integral structural member such as a mouth part inside, a soft plastic is inserted into the flexible wall cavity, and a hard plastic is inserted into the flexible wall cavity. is arranged to correspond to the integral structural member molding cavity, and then a pressure fluid is introduced into the ballison to expand the ballison in the mold and mold it into the shape of the cavity. Method of manufacturing containers. (2) When holding the parison in a split mold,
2. The method for manufacturing a container having a flexible wall according to claim 1, wherein both sides of the parison perpendicular to the extrusion direction are held between mold pinch-off parts.