JPH05200741A - Preformed object and heat-resistant bottle - Google Patents

Abstract

PURPOSE:To prevent the separation of an insert member from a mouth part and to provide good heat resistance to the mouth part. CONSTITUTION:In a preformed object consisting of a mouth part 11 having a screw thread part 15a and a support ring part 14, a body part 12 and a bottom part 13, an annular insert member 15 composed of a heat-resistant material is integrally provided to the outer peripheral part of the mouth part 11 and the inner surface of the insert member 15 is formed into a tapered surface expanding upwardly. At least one rotation stop member composed of a planar part extending in the peripheral direction of the insert member 15 is provided to the inner surface of the insert member 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a preform and a heat-resistant bottle capable of producing a bottle having a mouth with excellent heat resistance, and in particular, an insert made of a heat-resistant material arranged on the outer periphery of the mouth. The present invention relates to a preform in which a member is firmly fixed to an inner peripheral portion of a mouth, and a heat resistant bottle formed from the preform.

[0002]

2. Description of the Related Art In recent years, polyester bottles have a temperature of 80-95 ° C.
The so-called hot fill to fill the liquid of, the carbonated juice, bottles filled with lactic acid bacteria beverage, etc. will be pasteurized by hot shower, so that particularly excellent heat resistance is required near the mouth. It became so. This is because in hot fill, the mouth is first exposed to hot liquid, and in pasteurizing with a hot shower it is common to pour the hot shower from above the bottle.

However, in a polyester bottle obtained by ordinary biaxially stretch blow molding, the mouth portion is left unstretched, so that heat resistance cannot be imparted by stretching, and it is necessary to fill a liquid at 80 to 95 ° C. Can not serve.

Under these circumstances, various attempts have been made to impart heat resistance to polyester bottles, especially near the mouth. For example, a method of imparting heat resistance by crystallizing the mouth portion, a method of forming a preform having a multi-layered structure including a heat-resistant resin and a polyester resin so that a large amount of heat-resistant resin is arranged in the mouth portion, and the like are available. Being tried.

However, in the method of crystallizing the resin such as polyester disposed in the mouth, the mouth may be whitened or the mechanical strength of the mouth may be reduced.
In many cases, improvement in heat resistance cannot be expected so much. On the other hand, the heat resistance of the bottle obtained by the method of using the preformed body in which the preformed body is multi-layered and a large amount of heat resistant resin is arranged in the mouth part is However, it is not sufficient for continuous use under severe hot fill conditions of 90 ° C or higher.

Therefore, a method for improving the heat resistance of the mouth of the bottle by forming an annular insert member made of a resin having good heat resistance in advance and disposing it in the mouth of the preform. Is being considered.

[0007]

However, in a biaxially stretched blow molded bottle in which an insert member made of a resin having good heat resistance is arranged at the mouth, the insert member provided at the mouth is made of polyester resin. Although it is structured to be attached to the mouth of the bottle body, in general, adhesiveness between heat-resistant resin and polyester resin is often not good, and therefore the bottle body of the insert member made of heat-resistant resin Sticking to the mouth is not good. Therefore, it is difficult to prevent the insert member from coming off.

Therefore, an object of the present invention is to solve the above-mentioned inconvenience, the insert member does not come off from the mouth portion, and
It is an object of the present invention to provide a preform and a heat resistant bottle having a mouth with good heat resistance.

[0009]

As a result of earnest research for solving the above-mentioned problems, the present inventor has arranged an annular insert member made of a heat-resistant material on the outer peripheral portion of the mouth of the preform, and If a surface where the insert member joins with the inner peripheral portion of the mouth (hereinafter referred to as the inner surface of the insert member) is a tapered surface that expands upward, it is possible to provide the insert member surface with no special uneven portion. It has been found that the detachment of the insert member can be prevented.

That is, the preform of the present invention is a preform having a mouth portion having a screw thread portion and a support ring portion, a body portion, and a bottom portion, and a heat resistant material is provided on the outer peripheral portion of the mouth portion. Is integrally provided, and the inner surface of the insert member is a tapered surface that expands upward.

The heat-resistant bottle of the present invention is characterized in that the above preform is biaxially stretch blow molded.

The present invention will be described in detail below. First, the materials used for the preform of the present invention will be described. A material having excellent heat resistance is used as a material for forming the insert member arranged on the outer peripheral portion of the mouth of the preform of the present invention. Such heat-resistant materials include (1) blend polymers of polyarylate and polyethylene terephthalate, (2) blend polymers of polycarbonate and polyethylene terephthalate, (3) copolymers of thermoplastic polyester and polyarylate, polycarbonate ,(Four)
Aromatic polycarbonate, (5) Copolymer of methyl methacrylate and glutarimide, (6) Heat resistant copolyester, (7) Crystallized polyethylene terephthalate and
(8) Blend resins of inorganic fillers such as mica and glass may be used alone or in combination.

Specifically, U polymer U8400, U8450,
U8500, U8600 (manufactured by Unitika Ltd.), J320 (manufactured by Mitsui Petrochemical Co., Ltd.), Panlite (manufactured by Teijin Ltd.), Kaymax T-240, T-150 (manufactured by Sumitomo Chemical Haas Co., Ltd.) and THERMEX PCTA6761 (manufactured by Eastman Kodak Co., Ltd.) or the like can be used. U polymers are preferably used.

In the main body of the preform of the present invention, the inner peripheral portion of the mouth and the upper portion of the body near the mouth are mainly made of a heat-resistant resin for the purpose of increasing the heat resistance of the entire mouth of the bottle. Preferably consisting of Specifically, the inner peripheral portion of the mouth mainly made of heat-resistant resin is (a) co-injected with one or more of the resins (1) to (6) forming the insert member and polyethylene terephthalate. (B)
Crystallized polyethylene terephthalate layer, or (c) Resins (1) to (6) that form an insert member
One or two or more of the above and polyethylene terephthalate are blended and molded.

In the case of the multilayer structure of (a) above, the layer in contact with the insert member is made of one or more of the above resins (1) to (6), and the resin composition of this inner layer is the resin of the insert. When the composition is close to the composition, the adhesion between the insert member and the main body can be improved. Similarly, above
When the resin composition of the blend of (c) is close to the resin composition of the insert member, the adhesion between the insert member and the main body can be improved.

Further, in the case of the above-mentioned multilayer structure (a), if the inner layer of the mouth portion is made of a heat resistant resin, the heat resistance against hot fill can be improved.

The body and the bottom of the molded body are made of a polyester resin generally used for bottles, preferably polyethylene terephthalate. Resin (preferably the same as the one used for the inner circumference of the mouth)
The heat-resistant resin and polyethylene terephthalate may be co-injected to form a multilayer structure integrally with the mouth of the main body.

In the heat resistant material used in the present invention,
Stabilizers, pigments, antioxidants, thermal deterioration inhibitors, ultraviolet deterioration inhibitors, antistatic agents, within the range that does not impair the object of the present invention,
Additives such as antibacterial agents and other resins can be added in appropriate amounts.

Next, the structure of the preform of the present invention will be described. FIG. 1 is a schematic sectional view showing a preform according to an embodiment of the present invention. The preform 1 comprises a mouth portion 11 having a thread portion 15a and a support ring portion 14, a body portion 12 and a bottom portion 13, and an insert member 15 made of a heat resistant resin is arranged on the outer peripheral portion of the mouth portion 11. Has been done.

The insert member 15 extends from the upper end of the mouth portion to the lower end of the support ring 14, and has an external thread portion 15
a. The surface 17 where the insert member 15 is joined to the inner peripheral portion 16 of the mouth portion (hereinafter referred to as the inner surface of the insert member 15) is basically a cylindrical surface, but from the lower end of the support ring 14 to the upper end of the mouth portion. It has a tapered surface that expands upward. By making the inner surface 17 of the insert member 15 such a tapered surface, it is possible to prevent the opening of the insert member 15 from coming off the inner peripheral portion 16.

FIG. 2 is a partial sectional view showing the vicinity of the mouth of the preform 2 according to another embodiment. This preform 2 is
Similar to the preform 1 shown in FIG. 1, the insert member 25 having the screw thread portion 25a is arranged on the outer peripheral portion of the mouth portion, and the inner surface 27 of the insert member 25 has a tapered surface that expands upward. Has become. However, in this embodiment, the lower end of the insert member 25 extends only partway through the support ring 24. The flange-shaped lower end surface of the insert member 25 is a flat surface, and the inner peripheral portion 26 of the mouth portion is formed on this end surface.
Are closely attached to each other to form a support ring 24. When the support ring 24 has such a structure, it is possible to prevent damage due to stress applied when the bottle is supported during filling or transportation of the contents.

3 to 5 show examples of the AA cross section of the preform 1 shown in FIG. 1, respectively. As shown in FIG. 3, the inner surface 17 of the insert member 15 is basically circular in the circumferential direction, but the inner surface 17 extends in the circumferential direction and has at least one flat detent portion ( Plane portion) 38. By providing the rotation stopping portion 38 extending in the circumferential direction on the inner surface 17 of the insert member 15 in this way, it is possible to prevent the rotation of the insert member 15 following the plug when the plug is opened and closed.

It is preferable that one of the detent portions 38 has a surface expansion of about 45 ° or more. If the surface expansion is less than 45 °, the effect of preventing rotation is insufficient, while if it exceeds 45 °, the adhesion between the insert member 15 and the inner peripheral portion 16 of the mouth portion deteriorates. Although FIG. 3 shows an example in which one detent portion 38 is provided, a plurality of detent portions 48 may be provided all around as shown in FIG. By providing a plurality of rotation preventing portions in this way, the rotation prevention of the insert member can be enhanced.

Although a flat detent portion (flat surface portion) is illustrated in FIGS. 3 and 4, a curved detent portion extending in the circumferential direction is formed on the inner surface of the insert member 15 as shown in FIG. 58 can also be provided. In particular, as shown in FIG.
When a plurality of curved detents 58 having different curvatures are connected to each other on the entire circumference of the inner surface to make the entire circumference elliptical, the rotation prevention of the insert member at the time of opening and closing the spout can be enhanced.

Although FIGS. 3 to 5 have been described as the preform 1 shown in FIG. 1, respectively, they can be considered as a BB cross section of the preform 2 shown in FIG.

FIG. 6 is a partial sectional view showing the vicinity of the mouth of the preform 6 according to still another embodiment. Similar to the preforms 1 and 2 shown in FIGS. 1 and 2, the preform 6 has an insert member 65 having a thread portion 65a arranged on the outer peripheral portion of the mouth portion, and an inner surface 67 of the insert member 65 is Although it is a tapered surface, at least one or more through holes 62 are formed in the insert member 65 as a rotation preventing portion. Here, FIG. 7 shows a CC cross section of the preform 6 shown in FIG. The through hole 62 is filled with a resin that forms the inner peripheral portion 66 of the mouth during molding. Since the resin occupying the through hole 62 of the insert member 65 is continuous with the resin forming the upper part of the body, the resin occupying the through hole 62 functions as a wedge, so to speak, to prevent the insert member 65 from rotating when opening and closing the spout. It can be prevented. To enhance the prevention of rotation, it is preferable to form a plurality of through holes 62. More preferably, as shown in FIG. 7, one through hole 62 is replaced with another through hole.
62 is formed symmetrically with respect to the circumferential center.

If the through-hole 62 can be formed to be relatively large, one or both of the contact surfaces 68 and 69 of the through-hole 62 may be tapered so as to expand upward, and the inner surface of the insert member 65 may be formed. Insert member without taper on 67
65 can be prevented from coming off.

Further, the upper end surface of the insert member 65 is tapered.
When 63 is provided and the upper portion of the taper 63 is covered with the inner peripheral portion 66 of the mouth, the end face of the mouth becomes a flat surface without a step, the sealing performance by the stopper is improved, and the insert member 65 is more reliably removed. To be prevented.

The through hole 62 can be easily manufactured by providing a rod-shaped body such as a pin in the mold cavity when molding the insert member 65.

FIG. 8 is a partial cross-sectional view showing the vicinity of the mouth of the preform 8 according to another embodiment. This preform 8 is similar to the preforms 1, 2 and 6 shown in FIGS. 1, 2 and 6, and has an insert member 85 having a thread portion 85a.
Is disposed on the outer peripheral portion of the mouth portion, and the inner surface 87 of the insert member 85 is a tapered surface, but the insert member 85 has a protruding portion 851 on the lower side. In this way, in the upper part of the trunk,
The protrusion 851 of the insert 85 is the inner and outer surface layers of the molded body.
When the structure is surrounded by 86, 86, the heat resistance of the upper part of the body becomes greater. Further, since the adhesiveness between the insert member 85 and the molded body main body is enhanced, sufficient internal pressure resistance can be obtained even when the internal pressure rises due to the pasteurizing in the case of a carbonated gas-containing beverage.

FIG. 9 is a partial sectional view showing the vicinity of the mouth of the preform 9 according to still another embodiment. The shape of the insert member 95 shown in FIG. 9 is basically the same as the shape of the insert member 85 shown in FIG. 8 except that a protruding portion 951 is provided below. However, in this embodiment, the lower end of the insert member 95 has a support ring 94.
Extends only halfway. The flange-shaped lower end surface of the insert member 95 is a flat surface, and the inner peripheral portion 96 of the mouth portion is in close contact with this end surface to form a support ring 94. When the support ring 94 has such a structure, it is possible to prevent damage due to stress applied when supporting the bottle during filling and transport of the contents.

Although the inner surface of the insert member is tapered so as to expand upward as described above, separation of the mouth of the insert member from the inner peripheral portion can be prevented, but the adhesiveness is improved. In order to further increase the temperature, it is preferable that the surface of the insert member is subjected to a fine surface roughening treatment, a polar group is generated by a corona discharge treatment, or a pretreatment such as an adhesive is applied. As the fine surface roughening treatment, there is a method of previously forming an engraved surface by etching, for example, a grain pattern on the core side of the molding die, or performing a processing of increasing the surface roughness by sandblasting.

In the production of the preform of the present invention, for example, a die corresponding to the preform is used, the above-mentioned insert member compact is arranged on the outer periphery of the mouth of the die, and then the main body is formed. It can be formed by injection molding or the like.

A heat resistant bottle can be obtained by biaxially stretch blow molding the preform of the present invention.

[0035]

As described in detail above, in the preform of the present invention, an insert member made of a heat-resistant material is arranged on the outer peripheral portion of the mouth, and the inner surface of the insert member is expanded upward. Since the taper surface is a tapered surface, the insert member does not come off even if a special concave-convex portion is not formed on the joint surface between the insert member and the bottle main body.

Further, if the inner peripheral portion of the mouth portion is mainly made of a heat resistant resin, the mouth portion of the preform is mainly made of a heat resistant material, and the heat resistance of the mouth portion is guaranteed. Further, by providing the inner surface of the insert member with the rotation stopping portion extending in the circumferential direction, it is possible to prevent the rotation of the insert member when opening / closing the spout. Furthermore, by providing a protrusion below the insert member, it is possible to improve the heat resistance and internal pressure resistance of the upper part of the body of the bottle obtained therefrom.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing a preform according to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view showing the vicinity of the mouth of a preform according to another embodiment of the present invention.

FIG. 3 is a diagram showing an example of a cross section taken along the line AA of FIG.

FIG. 4 is a diagram showing another example of the AA cross section of FIG. 1.

5 is a diagram showing still another example of the AA cross section of FIG. 1. FIG.

FIG. 6 is a schematic cross-sectional view showing the vicinity of the mouth of a preform according to still another embodiment of the present invention.

7 is a diagram showing a cross section taken along the line CC of FIG.

FIG. 8 is a schematic cross-sectional view showing the vicinity of the mouth of a preform according to another embodiment of the present invention.

FIG. 9 is a schematic cross-sectional view showing the vicinity of the mouth of a preform according to still another embodiment of the present invention.

[Explanation of symbols]

 1 ... Preform 11 ... Mouth 12 ... Trunk 13 ... Bottom 14, 24, 64, 84, 94 ... Support ring 15, 25, 65, 85, 95 ...・ Insert member 15a, 25a, 65a, 85a, 95a ・ ・ ・ Screw portion 16, 26, 66, 86, 96 ・ ・ ・ Inner peripheral portion of mouth 17, 27, 67, 87, 97 ・ ・ ・ Insert member Inner surface 38, 48, 58 of rotation preventing portion 62 ... Through hole 63 ... Taper of upper end surface of insert member 68, 69 ... Joining surface of through hole 851, 951 ... Projection portion

Claims (7)

[Claims] 1. A preformed body comprising a mouth portion having a screw thread portion and a support ring portion, a body portion and a bottom portion, wherein an annular insert member made of a heat resistant material is integrally formed on an outer peripheral portion of the mouth portion. The preform is characterized in that the inner surface of the insert member is a tapered surface that expands upward. 2. The preformed body according to claim 1, wherein
A preform, wherein the inner surface of the insert member has at least one detent portion extending in the circumferential direction. 3. The preformed body according to claim 2, wherein
The preformed body, wherein the rotation stopping portion is a flat surface portion formed on at least a part of the inner surface. 4. The preformed body according to claim 2,
The preformed body, wherein the rotation stopping portion of the insert member is a through hole. 5. The preformed body according to claim 1, wherein the insert member has a protruding portion downward. 6. The preformed article according to claim 1, wherein an inner peripheral portion of the mouth portion is mainly made of a heat resistant resin. 7. A heat resistant bottle obtained by biaxially stretch blow molding the preform according to any one of claims 1 to 6.