JP3050433B2 - Package - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a blister package. More specifically, the present invention relates to a blister package made of a polyester sheet bonded to a backing sheet by a thermal adhesive method.

[0002]

2. Description of the Related Art Generally, a rigid vinyl chloride sheet made of a copolymer of vinyl chloride and vinyl acetate is used as a blister, which is a package obtained by thermoforming a thermoplastic resin sheet. Cured vinyl chloride sheet from 60 ° C to 120
It is molded into blisters by heating to ℃ and softening and pressing into a mold. Put food, pharmaceuticals, cosmetics, toiletries, stationery, sundries, tools, electrical parts, electrical products, etc. in the transparent polyvinyl chloride blister formed in this way, and glue it to the paper mount with adhesive The package has been widely used.

[0003] However, vinyl chloride contains chlorine in the molecule, so when waste is incinerated, chlorine chloride, hydrogen chloride,
Dioxins are generated and corrosion of incinerators, air pollution, etc. have become problems, and alternatives are being sought. As a substitute for vinyl chloride blister, a transparent and high-strength amorphous polyethylene terephthalate (A-PET)
Is considered. However, the A-PET sheet can be formed into a container or a blister by thermoforming similarly to the vinyl chloride sheet, but cannot be attached to the mount using a generally used adhesive such as vinyl chloride.
The A-PET sheet can be bonded to the backing paper with a special adhesive, but the adhesive is expensive, it takes time to obtain a predetermined strength, and the A-PE
There is a drawback that T may be whitened due to the solvent of the adhesive and the appearance is deteriorated. Further, in order to heat-bond the A-PET sheet to the backing sheet, it is necessary to heat the sheet to 260 ° C. or more, which is the melting point of the A-PET, and even if the A-PET sheet adheres to the backing sheet, crystal whitening occurs and the appearance becomes poor. There is a disadvantage that.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems, and it is an object of the present invention to heat a backing sheet with a polyester-based blister that does not generate harmful gas during incineration. It is intended to provide a bonded package.

[0005]

That is, the present invention is to obtain a polyester sheet having a thickness of 50 to 1500 μm having a copolymerized polyester layer having at least one side softened or melted at 110 to 230 ° C. by thermoforming. This is a package in which the obtained molded article is bonded to paper.

[0006] The copolyester in the present invention is:
Polyester having a polyethylene terephthalate structure based on terephthalic acid and ethylene glycol, and dibasic acids such as isophthalic acid, phthalic acid, glutaric acid, adipic acid, sebacic acid, azelaic acid, dodecanejarvonic acid, cyclohexane jacarboxylic acid, and naphthalene dicarboxylic acid A copolymer obtained by copolymerizing diethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, butanediol, polybutylene glycol, neopentyl glycol, cyclohexane dimethanol, an ethylene oxide adduct of a bisphenol derivative, or the like as a glycol, such as sanic acid or dimer acid. And any material that softens or melts at 110 to 230 ° C can be selected. As the copolymerized polyester, one kind may be used, or two or more kinds may be used by blending. Further, it may be used by blending with a homoester such as polyethylene terephthalate.

In the present invention, the softening point is measured by a penetration method, and the melting point is measured by a DSC method. If the softening or melting temperature is lower than 110 ° C., troubles such as sticking occur at the time of molding, which is not preferable. On the other hand, if the temperature exceeds 230 ° C., it is necessary to increase the heat bonding temperature, and furthermore, a problem such as crystal whitening of the bonded portion to deteriorate the appearance occurs, which is not preferable. The lower the crystallinity, the better the suppression of crystal whitening. Heat of crystal fusion measured by the DSC method 8 Cal / g
Or less, preferably 5 Cal / g or less, more preferably 3 Cal / g or less.
g or less.

In the present invention, the thickness of the polyester sheet is preferably from 50 μm to 1500 μm. If the thickness is less than 50 μm, the shape maintenance of the package is insufficient, which is not preferable. Conversely, when the thickness exceeds 1500 μm, the protection of the package becomes excessive and economically disadvantageous, which is not preferable. Within this range, it can be set arbitrarily according to the purpose of use.

The polyester sheet in the present invention may have a single-layer structure composed of only the above-mentioned copolymerized polyester layer or a multilayered structure having the copolymerized polyester layer as a surface layer. In the case of a multilayer structure, only one surface may be the copolyester layer, or both surfaces may be the copolyester layer. In the case of a multilayer structure, a structure including a layer made of polyethylene terephthalate is particularly recommended from the viewpoint of mechanical properties and economy. That is, a multilayer structure in which a copolymer polyester layer is laminated on one side or both sides of a layer made of polyethylene terephthalate is particularly preferable.

The polyethylene terephthalate used in the polyethylene terephthalate layer may be a virgin resin or a recovered resin. Examples of the recovered resin include waste resin generated in a process of manufacturing fibers, films, and molded articles using polyethylene terephthalate as a raw material, and a recovered resin obtained by recovering a PET bottle. Further, a mixture of a small amount of copolymer resin, which is a recovered product of the multilayer structure sheet manufactured by the method of the present invention, may be used. The method using these recovered resins is economically advantageous and is a particularly recommended embodiment.

The thickness of the copolymer layer in the multilayer structure is not particularly limited, but is preferably 3 μm or more, more preferably 5 μm or more. The structure method in the case of a multilayer structure is not particularly limited, but is preferably performed by a co-extrusion method. The polyester sheet in the present invention may contain an antistatic agent, U
V absorbers, coloring agents, lubricants, hiding agents, and other additives may be added. The polyester sheet may be an unstretched sheet formed by melt extrusion or a stretched sheet uniaxially or biaxially stretched.
Unstretched or weakly stretched sheets are recommended from the viewpoint of thermoformability. Example

Example 1 Terephthalic acid 70 mol%, isophthalic acid 30 mol%, ethylene glycol 98 mol%, diethylene glycol 2
A copolymerized polyester resin having a softening point of 180 ° C. and having a softening point of 180% by mol was melt-extruded and formed into a transparent sheet having a thickness of 250 μm. The sheet was heated to 100 ° C., and a transparent dome-shaped blister was formed by pressure forming. Place the items in the blister and, as shown in FIG.
It was placed on a 0 mm paperboard, and the edge portion was heat-bonded by applying a pressure of 1 kg / cm ² for 2 seconds by pressing and heating with a hot plate heated to 250 ° C. The adhesive strength between the blister and the paperboard was strong, and the adhesive part was transparent and had a good appearance.

Example 2 The copolyester and polyethylene terephthalate used in Example 1 were formed into a transparent sheet having a total thickness of 230 μm having a two-layer structure of 10 μm and 220 μm by melt coextrusion. The transparent sheet
A transparent dome-shaped blister was formed by heating to 0 ° C. and pressure forming to form the copolymerized polyester layer inside. The product was put in the blister and adhered to a paperboard having a thickness of 1.0 mm in the same manner as in Example 1. The adhesive strength between the blister and the paperboard was strong, and the adhesive part was transparent and had a good appearance.

Comparative Example 1 In Example 2, the copolymerized polyester layer was replaced with polyethylene terephthalate, and a transparent sheet having a thickness of 230 μm and consisting entirely of polyethylene terephthalate was obtained. The sheet was heated to 100 ° C., and a transparent dome-shaped blister was formed by pressure forming. An article was put into the blister and thermally bonded to a 1.0 mm thick paperboard in the same manner as in Example 2, but could not be completely thermally bonded.

Example 3 In Example 2, the composition of the copolymerized polyester layer was changed to 95 mol% of terephthalic acid, 5 mol% of sebacic acid, 73 mol% of ethylene glycol, 3 mol% of diethylene glycol, and 24 mol% of neopentyl glycol. Example 2
A transparent sheet having a total thickness of 230 μm was obtained in the same manner as described above. The sheet was heated to 100 ° C., and a transparent dome-shaped blister was formed by pressure forming. The articles were put in the blisters and heat-bonded to a 1.5 mm thick paperboard in the same manner as in Example 2. The adhesive strength between the blister and the paperboard was strong, and the adhesive part was transparent and had a good appearance.

[0016]

The blister made of the polyester-based sheet according to the present invention contains polyester as a main component, so that no harmful components are generated during incineration, and the blister is excellent in transparency and mechanical properties. Furthermore, since it can be bonded to the backing paper by the thermal bonding method, a safe package without concern for environmental pollution can be manufactured at low cost.

[0017]

[Brief description of the drawings]

FIG. 1 shows a method of thermal bonding between a blister and a backing sheet. An object to be packaged is placed in a blister 1, placed on a paperboard 2 serving as a backing sheet, and an edge portion is added by a hot plate 3. It is explanatory drawing which showed the method of heat-bonding by pressure heating.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1; Blister made of polyester sheet 2; Paperboard 3; Hot plate 4;

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B65D 75/00-75/36

Claims (2)

(57) [Claims] 1. A molded product obtained by thermoforming a polyester sheet having a thickness of 50 to 1500 μm which is softened or melted at least at 110 to 230 ° C. on one side but has a copolymerized polyester layer is thermally bonded to paper. Packaging. 2. The package according to claim 1, wherein the polyester sheet has a multilayer structure including a polyethylene terephthalate layer.