JP2909880B2 - Tube head of squeezed tube container and method of manufacturing the tube head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tube head of a squeezed tube container for containing a creamy or viscous product containing an organic solvent, such as a rubber-based adhesive, an epoxy-based adhesive, and the like.

[0002]

2. Description of the Related Art Saponified ethylene-vinyl acetate copolymer (hereinafter abbreviated as EVAL) for organic solvents such as toluene, benzene, cyclohexanone, cyclohexanol, petroleum ether and xylene, for example, a product of Kuraray Co., Ltd. It is known that EVAL has effective corrosion resistance, chemical resistance and gas impermeability, and it is known that EVAL is used to form bottles and cans for containing products containing organic solvents as described above. .

[0003] The applicant of the present invention discloses that a thick inner layer (about 350 µm thick) made of a polyolefin resin, for example, polyethylene (hereinafter abbreviated as PE), in addition to a thin inner layer (about 70 µm thick) of EVAL. When extruding an integral composite tube tube by laminating the outer layers, PE is made to contain an appropriate amount of inorganic powder or granular material, whereby the molding shrinkage of the outer layer of PE and the warpage of the molded product when molded are obtained. To EVAL
The inner and outer layers do not peel during extrusion molding, and no cracks occur in the inner and outer layers according to the molding shrinkage of the molded product and the warpage of the molded product when molded. Can be manufactured in Japanese Patent Publication No. 6-41307.
No. (JP-A-63-22354).

[0004]

In the above-mentioned prior proposal, one end of a composite tube tube cut to an appropriate length is fitted to a core having a circular cross section having an inner die of a tube head forming die at an upper part, and the above-mentioned molding die is formed. It discloses that the molten EVAL is injected into the cavity, an EVAL tube head is formed on the inner periphery of one end of the tube cylinder, and the EVAL of the inner layer of the tube cylinder and the EVAL of the tube head are integrally fused. Since the cost of EVAL is about six times that of PE, the tube head is thick, and the amount of EVAL used is large, the cost of the manufactured tube container is very high.

Therefore, a five-layer laminated sheet (150 μm thick) in which a PE layer is adhered to both sides of a thin layer of EVAL with adhesive layers.
Punch out a donut piece of the same size as the end wall of the tube head, put it in a tube head mold so that this donut piece is located on the inner surface of the end wall, and then injection-mold a thick tube head with PE outside However, since EVAL does not exist on the inner periphery of the outlet of the tube head, it is impossible to prevent the organic solvent from volatilizing from the cylindrical wall of the outlet.

[0006]

DISCLOSURE OF THE INVENTION The present invention has been developed to solve the above-mentioned problems. Claim 1 has an end wall, a squeeze port which projects forward from the center of the end wall,
In a tube head of a squeezed tube container having a head member formed of a polyolefin-based resin integrally protruding rearward from a peripheral edge portion of an end wall and having a cylindrical wall fitted to a front end inner periphery of a flexible tube cylinder, A small-diameter cylindrical portion fitted to the inner periphery of the squeeze port, an end wall along the inner surface of the end wall,
Large-diameter cylindrical portion fitted to the inner periphery of the cylindrical wall, and a large diameter than the large-diameter tubular portion, ethylene vinyl acetate copolymerization with a flange portion protruding outward from around the large-diameter tubular portion integrally A thin-walled cylindrical barrier material formed of a combined saponified material and a cylindrical wall formed integrally with the outside of the cylindrical barrier material and having a rearward length longer than a large-diameter cylindrical portion of the cylindrical barrier material. The head member has a flange portion of the cylindrical barrier material bites into the head member, the rear end of the large-diameter cylindrical portion of the cylindrical barrier material, the rear end of the cylindrical wall of the head member located after the rear end It is characterized by being locked at the inward thickening. According to another aspect of the present invention, there is provided an end wall, a squeeze port protruding forward from a center portion of the end wall, and a cylindrical wall protruding rearward from a peripheral portion of the end wall and fitted to an inner periphery of a front end portion of a flexible tube cylinder. In the method for manufacturing a tube head of a squeezed tube container having a head member molded of a polyolefin resin integrally provided with a squeezed tube, a small-diameter cylindrical portion fitted to the inner periphery of the squeezed port, an end wall along the inner surface of the end wall parts, the large-diameter cylindrical portion fitted to the inner periphery of the cylindrical wall, and a large diameter than the large-diameter tubular portion, thin cylinder having a collar portion protruding outward from around the large-diameter tubular portion integrally The head member having a cylindrical barrier material formed from a saponified ethylene-vinyl acetate copolymer, and having a cylindrical wall having a rearward length longer than the large-diameter cylindrical portion of the cylindrical barrier material outside the cylindrical barrier material. Are integrally formed, and the rear end of the large-diameter cylindrical portion of the cylindrical barrier material is moved from the rear end. Wherein the locking at the rear of the inward thickened portion of the cylindrical wall of the head member located.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the illustrated embodiment, reference numeral 10 denotes a polyolefin resin, for example, polyethylene, having a thickness of about 1.
With a 5 mm head member, the end wall 11, a squeezing port 12 protruding forward from the center of the end wall, and a rearward protruding from the peripheral edge of the end wall, are fitted to the inner periphery of the front end of the flexible tube tube 30. A cylindrical wall 13 is provided integrally. The end wall 11
Usually, there is an uphill taper towards the base of the squeeze outlet.

Reference numeral 20 denotes a cylindrical barrier material having a thickness of about 0.7 mm formed of saponified ethylene-vinyl acetate copolymer = EVAL. In FIG. 1, a small-diameter fitting member fits into the inner periphery of the squeezing port 12 of the head member. A cylindrical portion 22, an end wall portion 21 along the inner surface of the end wall 11, a large-diameter cylindrical portion 23 fitted on the inner periphery of the cylindrical wall, and a front end of the large-diameter cylindrical portion having a diameter larger than the large-diameter cylindrical portion. Has an annular flange portion 24 that protrudes outward from the periphery. Collar 24
The amount of protrusion from the end wall portion is appropriately determined according to the thickness of the head member. When the thickness of the head member is 1.5 mm as described above, the protrusion amount is about 1 mm.

In the tube head according to the present invention, the thin cylindrical barrier material 20 is formed by EVAL, the formed cylindrical barrier material is loaded into a molding die of a head member, and insert molding is performed outside the cylindrical barrier material. The head member is formed of polyethylene so as to be integral with the cylindrical barrier material, and the mold is released. At this time, the rearward length of the cylindrical wall 13 of the head member is set to the large diameter cylindrical portion of the cylindrical barrier material. 23 is slightly longer than the backward length (△ L). ΔL may be about 2 mm.

As a result, the flange portion 24 that protrudes outward from around the front end of the large-diameter cylindrical portion of the cylindrical barrier member 20 bites into the boundary portion between the end wall 11 and the cylindrical wall 13 of the head member 10 and simultaneously The inner periphery of the rear end of the wall 13 is thickened inward by the thickness of the large-diameter cylindrical portion 23 of the cylindrical barrier material, and the thickened portion 14 locks the rear end of the large-diameter cylindrical portion 23. Therefore, even if the EVAL cylindrical barrier member 20 and the polyethylene head member 10 have poor adhesion, the cylindrical barrier member is securely held mechanically inside the head member, and the end wall 11 of the head member. The squeeze port 12 and the cylindrical wall 13 are covered from the inside to make the tube head corrosion resistant, chemical resistant and gas impermeable.

To make a squeezed tube container, a thickness of 2
A seamless flexible tube tube in which an inner layer 32 and an outer layer 33 each having a thickness of 140 μm are integrally formed of a mixed resin of polyethylene and an adhesive resin inside and outside an EVAL intermediate layer 31 of 0 μm, and fitted outside the cylindrical wall 13 of the head member. Then, the tube wall 13 is fitted into the inner periphery of the end of the tube tube 30, and the end of the tube tube is welded to the outer periphery of the tube wall 13 and the peripheral edge of the end wall 11 by heat sealing. The inner layer 32 of the tube tube is a mixed resin of polyethylene and an adhesive resin, the tube wall 13 and the end wall 1.
Since the outer surface of 1 is made of polyethylene, it is strongly welded.
Further, since the intermediate layer 31 of the tube tube 30 is made of EVAL, the organic solvent does not volatilize from the tube tube. The product is filled inside from the rear end of the tube tube, and after filling, the rear end portion of the tube tube is folded flat, heat-sealed and closed.

If necessary, the forward length of the squeezing port 12 of the head member is also slightly longer than the forward length of the small-diameter cylindrical portion 22 of the cylindrical barrier material, as shown in the figure, so that the front end of the squeezing port can be formed. Small-diameter cylindrical portion 22 of cylindrical barrier material around the circumference
And the thickened portion 15 may lock the front end of the small-diameter cylindrical portion.

In the cylindrical barrier material shown in FIG. 1, an annular flange portion 24 extends outward from around the front end of the large-diameter cylindrical portion, but as shown in FIG. 2, it extends from the front end of the large-diameter cylindrical portion. Tsuba 2
In addition to 4, one or more flanges 25, 25 protruding from the middle of the large-diameter cylindrical portion, and a flange 26 protruding from around the small-diameter cylindrical portion 22 may be provided on the cylindrical barrier material. The flange is not limited to a ring, but may be a spiral as shown in FIG.

[0014]

As is clear from the above, according to the present invention, since the entire inner surface of the tube head formed of the polyolefin resin on the outside is covered with the cylindrical barrier material made of EVAL, the product containing the organic solvent is contained. Used in a squeezed tube container, it is possible to reliably prevent deterioration of the product due to evaporation of the organic solvent. Since the thickness of the cylindrical barrier material is thin, the amount of expensive EVAL used is small, and the cost does not increase.
Furthermore, the cylindrical barrier material of EVAL has its flange portion biting into the head member, and the rear end of the large-diameter cylindrical portion is locked at the inward thickened portion formed at the rear portion of the cylindrical wall of the head member. Therefore, it is reliably held against the head member formed of the polyolefin resin having poor adhesiveness and does not separate.

[Brief description of the drawings]

FIG. 1 is an elevational view in which a part of a squeezed tube container using a tube head of the present invention is shown in cross section and a main part is enlarged.

FIG. 2 is a side view of another example of the cylindrical barrier material, with a half sectioned.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 head member 11 end wall 12 squeezing port 13 cylindrical wall 14 thickened portion 20 cylindrical barrier material 21 end wall portion 22 small diameter cylindrical portion 23 large diameter cylindrical portion 24 flange portion 25 flange portion 26 flange portion 30 tube cylinder 31 intermediate layer 32 inner layer 33 Outer layer

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI B29K 55:00

Claims (2)

(57) [Claims] 1. An end wall, a squeeze port protruding forward from a central portion of the end wall, and a rearward protruding portion from a peripheral portion of the end wall;
In a tube head of a squeezed tube container having a head member formed of a polyolefin resin integrally provided with a tube wall fitted to the inner periphery of a front end portion of a flexible tube tube, the tube head is fitted to the inner periphery of the squeeze port. diameter tubular portion, the end wall portion along the inner surface of the end wall, the large-diameter cylindrical portion fitted to the inner periphery of the cylindrical wall, and a large diameter than the large-diameter tubular portion, out of around its large-diameter tube portion A thin-walled cylindrical barrier material formed of a saponified ethylene-vinyl acetate copolymer having a flange portion integrally formed on the cylindrical barrier material, and a thin-walled cylindrical barrier material integrally formed outside the cylindrical barrier material. A head member having a cylindrical wall whose rearward length is longer than the diameter cylindrical portion, the flange portion of the cylindrical barrier material bites into the head member, and the rear end of the large diameter cylindrical portion of the cylindrical barrier material is The head member located behind the rear end is locked by the inward thickening at the rear of the cylinder wall. Squeeze tube container tube head according to claim. 2. An end wall, a squeeze port protruding forward from a center portion of the end wall, and a rearward protruding portion from a peripheral portion of the end wall;
In a method for manufacturing a tube head of a squeezed tube container having a head member formed of a polyolefin resin integrally provided with a tube wall fitted to the inner periphery of a front end portion of a flexible tube tube, diameter tubular portion fitted, the end wall portion along the inner surface of the end wall, the large-diameter cylindrical portion fitted to the inner periphery of the cylindrical wall, and a large diameter than the large-diameter tubular portion, the large diameter <br / > A thin-walled cylindrical barrier material integrally having a flange protruding out from around the cylindrical portion is molded from a saponified ethylene-vinyl acetate copolymer, and the cylindrical barrier material is formed outside the cylindrical barrier material. The head member having a cylindrical wall whose rearward length is longer than the large-diameter cylindrical portion is integrally formed, and the rear end of the large-diameter cylindrical portion of the cylindrical barrier material is positioned at a position behind the rear end. Squeeze tube container lock, locked at an inward thickening at the rear of the wall Method of manufacturing a Buheddo.