JPH10167357A - Synthetic resin bottle body and its production method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the sealing performance of a cap and the top end face of the bottle mouth cylindrical part of a blow molded bottle body provided with an inverted flange at the top end of the mouth cylindrical part. SOLUTION: This bottle body comprises a synthetic resin outer layer 2 forming a fixed shape outer shell, and a flexible synthetic resin inner layer 3 laminated freely peelable on the outer layer 2 and forming an inner bag. In this case, at the top end of a mouth cylindrical part 4 where a cap is screwed on, an inverted flange 5 with the inner layer 3 on the upper face, curved and inverted from the inside to the outside and having an outer diameter not hindering the screw assembly of the cap on the mouth cylindrical part 4 is integrally formed, and at the upper face of the inverted flange, a ring shape packing 10 is fixed as an insert material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an outer layer forming a fixed outer shell, and an inner layer forming a deformable inner bag is peelably laminated and formed on an outer layer forming a fixed outer shell without causing a change in appearance. TECHNICAL FIELD The present invention relates to a synthetic resin blow-molded bottle capable of pouring and using a content liquid without allowing outside air to enter a content liquid storage section, and a method for molding the same.

[0002]

2. Description of the Related Art In a synthetic resin blow-molded bottle composed of an inner layer forming a deformable inner bag and releasably laminated within an outer layer forming a fixed outer shell, the inner volume of the inner layer is reduced. In order to prevent the accompanying deformation, i.e., the crushing deformation from becoming irregular, the outer layer and the inner layer are fixed by bonding or the like at a part of the outer layer and the inner layer, for example, at least in the bottle portion and the bottom of the bottle. (See JP-A-4-339759).

[0003] In this type of laminated bottle, in the case of a bottle provided with a cap with a pump, the outer layer and the inner layer in the mouthpiece are fixed by positioning the upper end of the inner layer on the upper end surface of the outer layer. The upper end of the inner layer located on the upper surface of the outer layer,
This is achieved by sandwiching between the packing in the cap and the upper end surface of the outer layer.

[0004] By increasing the sandwiching width of the upper end portion of the inner layer between the packing in the cap and the upper end surface of the outer layer, the sandwiching strength is strengthened and the inner layer is securely fixed in the mouthpiece portion. JP-A-8-143080
The technique described in Japanese Patent Application Laid-Open Publication No. HEI 9-260926 has been proposed.

[0005] That is, the synthetic resin bottle described in the above publication has an outer layer forming an outer shell, and an inner layer forming an inner bag, which is releasably laminated on the upper end of a mouth portion of a blow bottle, from the inside to the outside. A reversing flange that is curved and reversed is integrally provided so that the upper surface of the reversing flange that forms the upper end surface of the mouth is formed by the upper end of the inner layer. The reversing flange is formed by blow molding the neck flange integrally with the bottle. It is composed of the remaining part of the excision.

[0006]

SUMMARY OF THE INVENTION The above-mentioned Japanese Patent Application Laid-Open No. 8-143 is disclosed.
In the synthetic resin bottle described in Japanese Patent Publication No. 080, since the reversing flange at the upper end of the mouthpiece is integrally formed by blow molding, the bottle is formed by the inner surface of the inner layer that is not in contact with the blow mold during molding. However, it is difficult to obtain sufficient smoothness on the upper surface of the reversing flange, and there is a problem that the sealing performance between the upper surface of the reversing flange and the lower surface of the packing in the cap may not be sufficient.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made to solve the above-mentioned problems in the prior art. In a blow molded bottle provided with an inverted flange at the upper end of a mouthpiece, a cap and a bottle are provided on the mouthpiece. An object of the present invention is to improve the sealing property between the end face.

[0008]

A structural means according to the present invention for achieving the above object comprises an outer layer made of a synthetic resin for forming a fixed outer shell, and an outer layer which is releasably laminated on the outer layer to form an inner bag. It is a blow-molded bottle composed of an inner layer made of a flexible synthetic resin, and the cap of the bottle is bent inward from the inside to the outside at the upper end of a cylindrical mouthpiece to which the cap is screwed and assembled. Having a reversing flange formed integrally with the reversing flange, the reversing flange has an outer diameter that does not interfere with the screwing of the cap to the mouthpiece, and the upper end of the inner layer is located on the upper surface. That a ring-shaped packing is fixed as an insert material on the upper surface of this reversing flange,
It is in.

It is practically preferable that the cap is a cap with a pump.

Further, the method of the present invention comprises a synthetic resin outer layer forming a fixed outer shell, and a flexible synthetic resin inner layer formed releasably on the outer layer to form an inner bag. A method of blow molding a bottle, a blow head having a lower surface of a step portion as a horizontal circumferential pressing surface, and a ring-shaped packing detachably mounted as an insert material below the pressing surface, a parison. The cap is pushed into the upper end opening to a predetermined position, and the cap is screwed and assembled. At the upper end of the cylindrical mouthpiece, the curve is inverted from the inside to the outside, and is sufficiently larger than the outer diameter of the mouthpiece. A neck burr having a connection flange having a large outer diameter is integrally formed, and the packing is heat-welded to the upper surface of the connection flange. It is cut off by remaining in the mouth tube portion Te, in.

The blow head has an air supply hole formed in the center thereof, an outer diameter substantially equal to the inner diameter of the parison, and an inclined guide surface which is reduced in diameter at the lower end of the outer peripheral surface. On the upper end of the peripherally provided small-diameter cylindrical portion, a large-diameter cylindrical portion whose diameter is expanded via a horizontal circumferential pressing surface is formed, and packing is detachably fitted to the upper end of the small-diameter cylindrical portion so as to be detachable. It is good to carry out molding.

[0012]

The reversing flange formed on the upper end of the mouthpiece portion of the bottle is formed by bending the upper end portion of the mouthpiece portion inward and then turning it outwardly. The upper end of the inner layer is located on the upper surface, and the packing is fixed to the upper surface of the upper end of the inner layer.

Therefore, when the cap is screwed into the mouthpiece, the inner surface of the cap is pressed tightly against the upper surface of the packing, whereby the upper end of the inner layer and the packing are pressed between the cap and the outer layer. Is firmly clamped and fixed, and the sealing between the cap and the upper end surface of the barrel portion is reliably maintained due to the sufficient smoothness of the packing upper surface.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 shows a bottle 1 according to the invention.
The bottle 1 in which a cap 8 with a pump is screwed and assembled and a main body portion of the cap 8 are shown in a semi-longitudinal view. The bottle 1 has an outer layer 2 made of high-density polyethylene resin and an inner layer 3 made of nylon. Are formed by blow molding from a parison extruded into a laminated cylindrical shape by co-extrusion forming means, and a thread for screwing and assembling the cap 8 is engraved on the outer peripheral surface of the cylindrical tube portion 4. Have been.

As shown in FIG. 2, at the upper end of the mouthpiece portion 4,
By inverting the upper end portion of the barrel portion 4 from the inside to the outside, a ring-shaped inversion flange 5 having the same outer diameter as the barrel portion 4 is integrally connected in a state where the outer peripheral groove 6 is formed immediately below. Has been established.

The reversing flange 5 is formed by bending the upper end of the mouthpiece portion 4 from the inside to the outside so that the inner surface of the inner layer 3 is located on the upper surface. A ring-shaped packing 10 is fixed as an insert material on the upper surface of the reversing flange 5 formed by the inner surface of the inner layer 3.

Therefore, in the state where the cap 8 is screwed and assembled to the mouthpiece 4, the inner layer 3 is located between the flange plate 9 in the cap 8 and the upper end of the outer layer 2 constituting the reversing flange 5.
And the packing 10 are firmly clamped and fixed to achieve the immovable fixation of the upper end of the inner layer 3 to the outer layer 2 in the barrel 4 and the secure sealing between the flange plate 9 and the packing 10. I do.

When the cap 10 and the upper end of the outer layer 2 hold the upper end of the inner layer 3 and the packing 10, the outer peripheral groove 6 formed immediately below the inverting flange 5 functions as a means for imparting elasticity to the inverting flange 5. Therefore, the immovable clamping of the upper end of the inner layer 3 is made stronger and more stable.

FIGS. 3 to 5 show the essential parts of the embodiment of the molding method of the present invention. First, as shown in FIG. Then, the neck burr 7 is formed integrally with the bottle 1 by pressing with the blow head 11.

That is, the blow head 11 has an air supply hole 16 formed at the center thereof and a parison 20.
At the upper end of a small-diameter cylindrical portion 12 having an outer diameter approximately the same as or slightly larger than the inner diameter of the large-diameter cylindrical portion 14, a large-diameter cylindrical portion 14 expanded through a horizontal circumferential pressing surface 13 is formed. At the lower end of the outer peripheral surface of the small-diameter cylindrical portion 12, an inclined guide surface 15 that contracts downward is provided around the lower end, and the upper end of the small-diameter cylindrical portion 12 has substantially the same diameter as the large-diameter cylindrical portion 14. The packing 10 having the outer diameter of is detachably fitted to the outside.

Then, the blow head 11 is lowered from above into the upper end opening of the parison 20 set in the blow molding die 17 and the small-diameter cylindrical portion 12 at the tip is pushed. The upper end portion is expanded and curved outward, and the neck burr 7 is formed.

The blow head 11 is pressed against the flange 18 of the blow mold 17 at a predetermined position where the pressing surface 13 of the blow head 11 presses the upper surface of the packing 10 with the packing 10 and the neck burr 7 interposed therebetween. 11 stops,
By this pressing, the packing 10 is thermally welded to the upper surface of the neck burr 7, and thereafter, the air is sucked from the air supply hole 16 to blow-mold the bottle 1.

Neck burr 7 integrally formed with bottle 1
Has a connecting flange 7a which is bent inwardly from the upper end of the barrel portion 4 of the bottle 1 and then rises upward and turns outwardly. The outer diameter of the cylindrical portion 4 is sufficiently larger than the outer diameter, and the packing 10 is fixed to the upper surface thereof.

Neck burr 7 integrally formed with bottle 1
And the packing 10 after the completion of the blow molding of the bottle 1
By being cut up and down at a cut position K at an outer diameter position equal to the outer diameter of the mouthpiece portion 4 of the connecting flange 7a, the bottle is cut off from the bottle 1 (see FIG. 4). Tube part 4
The inside portion of the connecting flange 7a remaining in a state of being connected to the upper end of the connecting flange 7a becomes the inverting flange 5 (see FIG. 5).

The cutting process of the connecting flange 7a of the neck portion burr 7 and the packing 10 is performed so that the connecting flange 7a has an outer diameter larger than that of the mouthpiece portion 4 and the outer peripheral groove 6 is provided immediately below the connecting flange 7a. With this configuration, the outer peripheral groove 6 is fitted with a receiving plate, and is achieved with a cylindrical blade having a diameter equal to the outer diameter of the barrel portion 4 from above, thereby ensuring safe, reliable and accurate operation. Can be more easily achieved.

[0026]

Since the present invention has the above-described structure, the following effects can be obtained. Since the packing is previously fixed to the upper surface of the reversing flange, which serves as a sealing portion between the cap, the sealing property between the cap and the upper end surface of the bottle mouth cylinder portion is ensured by sufficient smoothness of the packing upper surface. Can be greatly improved.

The packing can be easily attached at the time of blow molding of the bottle using the packing as an insert material, and is completely safe unlike an adhesive or the like which may adversely affect the liquid content of the bottle. And it can be securely mounted.

[Brief description of the drawings]

FIG. 1 is a right half vertical sectional view showing a bottle according to an embodiment of the present invention with a cap attached.

FIG. 2 is an enlarged longitudinal sectional view of a main part of the embodiment shown in FIG.

FIG. 3 is a partially enlarged view showing a neck part burr molding state, showing one embodiment of the molding method of the present invention.

FIG. 4 is a partially enlarged view of the embodiment shown in FIG. 3 before a neck portion burr is cut off.

FIG. 5 is a partially enlarged view of the embodiment shown in FIG.

[Explanation of symbols]

 1; Bottle 2; Outer layer 3; Inner layer 4; Mouth section 5; Reversing flange 6; Outer peripheral groove 7; Neck burr 7a; Connecting flange 8; Cap 9; Flange plate 10; Packing 11; Blow head 12; Part 13; pressing surface 14; large-diameter cylindrical part 15; inclined guide surface 16; air supply hole 17; blow molding die 18; flange part 20; parison K;

Claims (4)

[Claims] 1. An outer layer made of a synthetic resin forming a fixed outer shell.
(2) and an inner layer (3) made of a flexible synthetic resin, which is releasably laminated on the outer layer (2) and forms an inner bag, in the blow molded bottle (1). ) Is bent inward from the inside to the outside at the upper end of the cylindrical mouthpiece (4) to be screwed and assembled, and the cap (8) is screwed into the mouthpiece (4). A reversing flange (5) having an outer diameter that does not interfere with the upper surface of the inner layer (3) is formed integrally with the upper surface of the inner layer (3), and a ring-like shape is formed on the upper surface of the reversing flange (5). A synthetic resin bottle with a packing (10) fixed as an insert material. 2. The synthetic resin bottle according to claim 1, wherein the cap (8) is a cap with a pump. 3. An outer layer made of a synthetic resin forming a fixed outer shell.
When blow molding the bottle (1) from (2) and the inner layer (3) made of a flexible synthetic resin that is peelably laminated on the outer layer (2) and forms the inner bag, Horizontal circumferential pressing surface (13)
And, a blow head (11) having a ring-shaped packing (10) removably attached as an insert material below the pressing surface (13), is pushed into a predetermined position into the upper end opening of the parison (20), At the upper end of the cylindrical mouthpiece (4) to which the cap (8) is screwed and assembled, it is curved and inverted from inside to outside, and is sufficiently larger than the outer diameter of the mouthpiece (4). A neck burr (7) having an outer diameter connecting flange (7a) is integrally formed, and the packing (10) is heat-welded to the upper surface of the connecting flange (7a) to form the neck burr (7). A method of molding a synthetic resin bottle, wherein a packing (10) is cut and removed by leaving the inside of the connecting flange (7a) as an inverted flange (5) in the mouthpiece (4). 4. A blow head (11) has an air supply hole (1) at its center.
6) is penetrated, has an outer diameter that is substantially the same as the inner diameter of the parison (20), and has a small-diameter inclined guide surface (15) that is reduced in diameter at the lower end of the outer peripheral surface. At the upper end of the cylindrical portion (12), a large-diameter cylindrical portion (14) whose diameter is enlarged via a horizontal circumferential pressing surface (13) is formed, and at the upper end of the small-diameter cylindrical portion (12), a packing is provided. (1
4. The method for molding a synthetic resin bottle according to claim 3, wherein 0) is detachably fitted to the outside.