JPH0684063B2 - Package and manufacturing method thereof - Google Patents

Description

TECHNICAL FIELD The present invention relates to a package having excellent moisture resistance, transparency, and easy removal of contents, and a method for producing the same.

Conventional technology If the packaging of medicines (tablets, capsules, etc.), cosmetics or foodstuffs is insufficient, the contents themselves may be easily altered, so the packaging should be done completely. It is also convenient in handling that the contents can be seen from the outside of the package.

Conventionally, in response to such a request, for example, a single layer sheet of polyvinyl chloride (PVC) or polypropylene (PP),
A package was used in which a composite sheet in which a vinyl chloride layer was adhered to both sides of polyethylene (PE) by a dry lamination method was used, and the contents were stored by a vacuum or / and pressure forming method.

However, a package formed of a single-layer sheet of PVC or PP is inferior in moisture resistance, and therefore this package is usually made of Al.
Although the moistureproof property was covered by putting it in the bag, the moistureproof property after opening the Al bag was a problem, and the manufacturing process such as loading into the Al bag was complicated and the manufacturing cost was increased.

Further, the package formed of a composite sheet of PE and PVC is practically almost satisfactory in terms of moisture proofness, but it is somewhat difficult to take out the contents. Furthermore,
Some new drugs being developed in recent years are required to have higher moisture resistance than ever before, and such a drug can be packaged with a composite sheet even if the moisture resistance is still improved. There is room left.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention The present invention relates to a package having improved moisture resistance in a conventional package, and also relates to an efficient manufacturing method thereof.

Means for Solving the Problems According to the present invention, there is provided a package formed by laminating a composite synthetic resin sheet having a recess for accommodating an article and a metal foil, the composite sheet being made of high density polyethylene. An outer layer made of a propylene-based polymer was attached to both surfaces of the core layer 3
A layered sheet, wherein the thickness of the core layer is 120 to 800 μm, the thickness of each outer layer is 15 to 80 μm, and the thickness of the core layer is 2.5 times or more the total thickness of the outer layers on both sides. There is provided a package characterized by the following.

Further, according to the present invention, there is provided a method for producing a package comprising laminating a composite synthetic resin sheet having a recess for accommodating an article and a metal foil, the composite sheet comprising a middle core layer made of high density polyethylene. A three-layer sheet in which an outer layer made of a propylene-based polymer is laminated on both sides, and the thickness of the core layer is
120 ~ 800μm, the thickness of each outer layer is 15 ~ 80μm,
The thickness of the core layer is 2.5 times or more of the total thickness of the outer layers on both sides, and in this composite sheet, a concave portion is formed by compressed air and / or vacuum forming, and after storing the article in the concave portion, This composite sheet and the metal foil are superposed so that this recess can be sealed with a metal foil, and between the outer layer and the metal foil on the opening side of the recess of the composite sheet, pressure contact is integrated while supplying heat from the metal foil side, There is provided a method of manufacturing a package, which is characterized in that a recess is sealed.

Action The package of the present invention is selected for clothing resin and molding method (lamination method)
It has a feature in two points, that is, selection.

First, as the material sheet of the conventional composite sheet, the one in which the PVC layer was laminated on both sides of the PE sheet by the dry lamination method was used, whereas the material sheet (composite sheet) of the present invention was formed on both sides of the PE layer. A PP film is laminated by the extrusion double-sided simultaneous laminating method. Here, the sheet refers to a sheet having a thickness of 100 μm or more.

The PE used for the PE sheet of the core layer should be selected from the viewpoints of strength, transparency, moisture resistance and ease of taking out the contents, and the density should be selected within the range described below in order to improve the moisture resistance by this method. Is desirable.

In particular, the significance of using the propylene-based polymer as both outer layers is that the outer layers not only prevent drawdown of the core layer sheet during molding, but also can be molecularly oriented by stretching and impart high moisture resistance. is there.

The package provided by the present invention is obtained by bonding a specific composite synthetic resin sheet having a recess for accommodating an article and a metal foil.

The composite synthetic resin sheet is vacuum and / or pressure formed to form a recess for accommodating an article.

The composite synthetic resin sheet used here is a three-layer sheet in which the core layer is mainly made of high-density polyethylene, and the outer layers made of a propylene-based polymer are laminated on both sides of the core layer. 120 ~ 800μm, each outer layer thickness
It is 15 to 80 μm, and the thickness of the core layer is 2.5 times or more the total thickness of the outer layers on both sides.

The high-density polyethylene that constitutes the core layer has a melt flow rate MFR ₂ (190 ° C) of 2 to 20 and a density of 0.94 to 0.9.
6, preferably 0.96 to 0.98, particularly preferably 0.965
Or 0.98.

The high-density polyethylene is preferably in the above-mentioned range in order to improve the strength, transparency and moisture resistance of the package and to obtain the rigidity suitable for the ease of taking out the contents (articles), and especially the melt flow rate. Rate ratio, ie MFR ₁₀ (190 ° C)
High density polyethylene with an MFR ₂ of 1 to 10 is preferred.

The propylene-based polymer that constitutes both layers is composed of polypropylene 60 to 97% by weight and ethylene polymer 40 to 3% by weight (total 100% by weight). From the viewpoints of transparency and strength, it is preferably used. The polypropylene is a polymer having propylene units of at least 90 mol% or more, and its melt flow rate is preferably 0.5 to 20.

The ethylene-based polymer also has the effect of improving the adhesion to the outer core layer. This ethylene-based polymer is a homopolymer of ethylene containing 50 to 100 mol% of ethylene, or a copolymerizable monomer other than ethylene, particularly a copolymer of at least one type of α-olefin with ethylene.

Such ethylene-based polymers include low crystalline or amorphous (that is, rubber) such as ethylene-propylene copolymer, ethylene-butene copolymer, high density polyethylene, medium density polyethylene, low density polyethylene,
There are crystalline copolymers of ethylene and other α-olefins, among which the following polymers can be shown as suitable examples.

(I) Low crystalline or amorphous copolymer of ethylene-propylene (rubber) Ethylene unit content 50 to 90 mol%, MFR ₂ (230 ° C) 0.1 to
20g / 10min, (ii) ethylene-1-butene low crystalline or amorphous copolymer (rubber) ethylene unit content 50-90 mol%, MFR ₂ (230 ° C) 0.1-
20g / 10min, (iii) crystalline polymer of ethylene MFR ₂ (190 ° C) 2-20g / 10min, density 0.900-0.975g / c
m ³ , (iv) High-density, medium- or low-density crystalline copolymer MFR ₂ (190 ° C) _{2 to} 20g / 10min, density 0.900 to 0.975g / c consisting of ethylene and another 1-olefin
m ³ , comonomer: 1-olefin containing 3 to 20 carbon atoms, for example propylene, 1-butene, 1-pentene,
1-hexene, 4-methyl-4-pentene, 1-octene, 1-decene, comonomer content: 0 to 20 mol%.

Part or all of the various olefin-based polymerizations or copolymers described in (i) to (iv) above may be modified products with unsaturated carboxylic acids or acid anhydrides thereof.

Preferred unsaturated carboxylic acids and acid anhydrides thereof are maleic acid, norbornene dicarboxylic acid, (meth) acrylic acid, maleic anhydride and norbornene dicarboxylic acid anhydride.

The composition ratio of the polypropylene and the ethylene-based polymer forming the outer layer is preferably within the above range in order to ensure suitable adhesiveness between the core layer and the outer layer.

Since the outer layer has the above composition ratio, the composite sheet used in the present invention has an adhesive force of 300 g / cm between the core layer and the outer layer.
Above, especially 500 g / cm 2 or more is preferable.

The composite sheet usually has a thickness of 150 to 960 μm, the core layer has a thickness of 120 to 800 μm, the outer layers on both sides are in the range of 15 to 80 μm, and the thickness of the core layer is on both sides. Is more than 2.5 times the total thickness of the outer layers.

The core layer needs to be thick enough as the base layer of the composite sheet,
Further, both outer layers are provided in order to compensate for the fact that the high-density polyethylene constituting the core layer is inferior in vacuum and / or pressure air moldability and stretch orientation, and the thickness range and ratio deviate from this range. Therefore, it is not possible to obtain sufficient effects in terms of moisture resistance and ease of taking out articles.

The composite sheet having the above structure can be manufactured by various methods.
For example, there is a dry lamination method in which a preformed center core layer and both outer layers are laminated by interposing an adhesive such as urethane on the interposition surface.

A preferred method for producing the composite sheet constituting the package of the present invention is a so-called extrusion double-sided simultaneous laminating method, which enables efficient production. This extrusion double-sided simultaneous laminating method is one in which the core layer is sequentially melt-extruded between two preformed outer layers, and is extruded by rolls from both sides to form a composite sheet. Can be manufactured well.

An example of the extrusion double-sided simultaneous laminating method of the present invention is shown in FIG. 1. The core layer 1 includes a die 2 to a first roll 5 and a pressing roll 4.
In the vicinity of the pressure contact, preferably on the pressure contact in a molten state, the outer layer films 3, 3'are adhered to both surfaces of this core layer by the pressure contact of the first roll 5 and the pressing roll 4. The composite sheet 8 is formed through the second roll 6 and the third roll 7. FIG. 1 (2) is a cross-sectional view taken along the line AA of the obtained composite sheet. In the figure, 8 (1) and 8 (1 ') are outer layer films, and 8 (2) are middle core layer sheets. .

The fusion of the outer layer film and the core layer sheet in the composite sheet is performed by utilizing the sensible heat (about 170 ° C.) of the core layer. P
Although P and PE are originally difficult to be fused, the propylene-based polymer forming the outer layer has a specific composition as described above, so that the adhesiveness is good and a composite sheet excellent in transparency is obtained.

In the package of the present invention, for example, the composite sheet consisting of the above-mentioned specific three layers is subjected to pressure molding and / or vacuum forming to form a recessed portion, and the metal foil and the metal foil are pressed and integrated with each other to seal the recessed portion. It is obtained by

The metal foil used is a foil of various metals such as aluminum, and its thickness is usually in the range of 10 to 100 μ, particularly 15 to 60 μ.

In particular, when the package of the present invention is used for press-through packaging, an aluminum foil, which can be pressed and ruptured with an appropriate force, is suitable as the metal foil.

At least the side of the metal foil that is pressure-contacted and integrated with the composite sheet is preferably an adhesion-improving substance, for example, one coated with an adhesive polyolefin, and examples of the adhesive polyolefin include polyolefin such as polypropylene and halogen such as chlorine. An example is a halogenated polyolefin modified by.

That is, the long composite sheet is continuously heated to be in a moldable state, and the composite sheet is subjected to air pressure or / and vacuum suction in the mold to form the recess. After filling the contents into the formed recess, Al foil is attached, and then the process such as punching, perforation and printing is performed. PP is poor in pressure forming property and / or vacuum forming property, but according to the present invention, the vacuum forming property and / or the pressure forming property is improved by the orientation of the film for the outer layer and the orientation at the time of forming the composite sheet. , Moisture resistance and transparency are also improved.

The main molding is performed at 120 to 140 ° C, preferably 125 ° C or higher and 135 ° C or lower.

Although the degree of orientation can be changed by the heating temperature during pressure forming or / and vacuum forming, according to the present invention, moisture resistance of the package obtained by enabling pressure forming or / and vacuum forming particularly at low temperature And the transparency was further improved.

FIG. 2 shows an embodiment of the package of the present invention. Ie Al foil
10 is coated with a substance 11 for adhering to polyolefin, and a composite sheet 12 is adhered to the composite sheet 12 after forming a concave portion by pressure forming and / or vacuum forming. The sheet is an outer layer film 12 (1) and 12 (1 ') and a core sheet.
It is composed of 12 (2). 13 is a vacant space for storing contents such as medicines, cosmetics or foods.

Examples 1 to 8 First by the extrusion double-sided simultaneous laminating method shown in FIG.
The three-layer composite sheet shown in the table was molded. However, the high density polyethylene (HDPE) of the core layer had the following physical properties in all cases.

HDPE: MFR ₂ (190 ° C) = 5.5g / 10min Density 0.968g / cc Weight average molecular weight 67,000 MFR ₁₀ / MFR ₂ = 9.0 The propylene polymer used in the outer layer is the polymer shown in Table 1. It consists of composition ratios, and the physical properties of each component are as follows.

PP: MFR ₂ (230 ℃) = 6.0g / 10cc Ethylene content 4mol% EPR: Ethylene-propylene copolymer rubber Ethylene unit content 80mol% MFR ₂ (230 ℃) = 2g / 10min LLDPE (1) : Ethylene-4-methyl-1-pentene copolymer ethylene unit content 97 mol% MFR ₂ (190 ° C.) = 2.0 g / 10 minutes LLDPE (2): ethylene-1-butene copolymer ethylene unit content 97.5 Mol% MFR ₂ (190 ° C) = 2.0 g / 10 min LDPE: Low density polyethylene Density 0.921 g / cc Weight average molecular weight = 112,000 Next, from each composite sheet in Table 1, low temperature conditions (125 Vacuum / pneumatic molding under ~ 128 ° C) and vacuum / pneumatic molding under high temperature conditions (130-135 ° C)
Recess for No. capsule (dimensions: length 20.6 mm, width 8.8 mm,
(Depth of 7.4 mm) was molded and further pressure-contacted with aluminum foil to be integrated to produce the package of the present invention.

The aluminum foil used here was coated with chlorinated polypropylene to a thickness of 6 μm on the surface of the aluminum foil having a thickness of 20 μm and pressed against the composite sheet.

The performance of the obtained package was measured and evaluated as shown in Table 2.

However, each performance was evaluated by the following methods.

◯: Good, Δ: Slightly good, ×: Poor Further, each measurement condition is shown below.

DD: Drawdown property (unit: mm) The composite sheet was held horizontally between clamps with a span of 500 mm, and the amount of reduction (mm) in the central part after 55 seconds was measured.

Water vapor transmission rate: Unit (× 10 ^-6 g / 24hr / mmHg / 1 pocket) JIS Z-0
Condition B based on 208, ie temperature 40 ℃, relative humidity 90
It is the measured value under the condition of%.

However, the size of one pocket is the size of the recess for the No. 2 capsule.

Transparency: Shown in transmittance unit (%).

Permeability (%) at the bottom of the package pocket (concave)
Was measured using light having a wavelength of 555 μm. The measurement is A
Done based on STM D1003.

Ease of taking out contents: By pressing the bottom of the pocket part of the package containing the pharmaceutical capsule from the composite sheet side with a finger and crushing the pocket part, the aluminum foil can be extruded and ruptured by the pharmaceutical capsule. Then, the operation of taking out the medicinal capsule was carried out, and it was evaluated whether or not the rigidity and the flexibility when the pocket portion was crushed by the finger were appropriate.

Example 9 A composite sheet was produced by the dry lamination method to obtain the composite sheet shown in Table 1.

That is, the same 30 μm-thick film made of PP as in Example 1 was laminated on both sides of a preformed 450 μm-thick sheet of HDPE similar to that of Example 1 via polyurethane adhesives. Made into a composite sheet.

This composite sheet was subjected to the same pneumatic / vacuum forming as in Example 1 to produce the same packaging material.

The evaluation results of this packaging material are shown in Table 2.

Comparative Example Example 9 was repeated except that both outer layers were made of polyvinyl chloride film. The results are shown in Table 2.

Examples 10 to 14 Composite sheets were formed under the same conditions as in Example 1 except that the thicknesses of the core layer and the outer layer were set to the values shown in Table 3, and the same was used as a package.

The performance of each package was evaluated in the same manner as in Example 1. The results are shown in Table 4.

EFFECTS OF THE INVENTION As can be seen from Tables 1 to 4, the package of the present invention is superior to conventional products in terms of pressure forming property and / or vacuum forming property, moisture proof property, transparency and easiness of taking out contents. Excellent, especially when the extrusion double-sided simultaneous laminating method is adopted, the process becomes simpler than that of the dry laminating method.

[Brief description of drawings]

FIG. 1 (1) is an elevation view of an example of a composite sheet manufacturing apparatus, and FIG. 1 (2) is a laterally enlarged sectional view of the sheet. FIG. 2 is an explanatory view of the package. 1 ... Intermediate layer, 2 ... Die, 3, 3 '... Surface layer, 4 ...
… Presser roll, 5 …… first roll, 6 …… second roll,
7 ... Third roll, 8 ... Composite sheet, 8 (1) and 8
(1 ') ... outer layer film, 8 (2) ... core layer, 10 ...
… Al foil, 11 …… Adhesive material for polyolefin, 12 …… Composite sheet, 12 (1) and 12 (1 ′) …… Outer layer film,
12 (2) …… Core layer, 13 …… Vacancy.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shun Shun Fukuda 2-5 Ari Akidai Nishi, Ichihara City, Chiba Prefecture (56) Reference JP-A-59-26466 (JP, A) JP, U)

Claims (11)

[Claims] 1. A package comprising a composite synthetic resin sheet having a recess for accommodating an article and a metal foil attached to each other, the package comprising:
The composite sheet is a three-layer sheet in which an outer layer made of a propylene-based polymer is attached to both surfaces of a middle layer made of high-density polyethylene, the thickness of the middle layer is 120 to 800 μm, and the thickness of each outer layer is A package body, each having a thickness of 15 to 80 μm, wherein the thickness of the core layer is 2.5 times or more the total thickness of the outer layers on both sides. 2. The propylene-based polymer of both outer layers constituting the composite sheet is composed of polypropylene 60 to 97% by weight and ethylene polymer 40 to 3% by weight (total 100% by weight). The package according to claim 1. 3. Polypropylene is a polymer containing 90 mol% or more of propylene units and has MFR ₂ (230 ° C.) of 0.5 to 20.
And the ethylene polymer contains 50 to 100 mol% of ethylene.
A homopolymer of ethylene contained or a copolymer of ethylene with at least one or more kinds of other α-olefins other than ethylene.
The package according to item. 4. The MFR ₂ (190 ° C.) of the high-density polyethylene of the core layer constituting the composite sheet is 2 to 20, and the density is 0.94.
Claim 1 characterized in that it is ~ 0.98g / cc.
The package according to item. 5. High-density polyethylene MFR ₁₀ (190 ° C) / MFR
₂ (190 ° C.) is 1 to 10, The package according to claim 4, characterized in that 6. A process for producing a package, which comprises laminating a composite synthetic resin sheet having a recess for accommodating an article and a metal foil, wherein the composite sheet is provided on both sides of a core layer made of high density polyethylene. A three-layer sheet in which an outer layer made of a propylene-based polymer is laminated, and the core layer has a thickness of 120 to 800.
μm, the thickness of each outer layer is 15 to 80 μm, the thickness of the core layer is 2.5 times or more the total thickness of the outer layers on both sides, and this composite sheet is recessed by air pressure and / or vacuum forming. After forming a part and storing an article in the recess, the composite sheet and the metal foil are overlapped so that the recess can be sealed with a metal foil, and the outer layer on the opening side of the recess of the composite sheet and the metal foil In between, a method for producing a packaging body, characterized in that the concave portion is hermetically sealed by pressure contact and integration while supplying heat from the metal foil side. 7. The propylene polymer of both outer layers constituting the composite sheet is composed of 60 to 97% by weight of polypropylene and 40 to 3% by weight of ethylene polymer (total 100% by weight). The manufacturing method according to claim 6. 8. A polypropylene containing 90 mol% or more of propylene units, wherein MFR ₂ (230 ° C.) = 0.5-
20, wherein the ethylene-based polymer is a homopolymer of ethylene containing 50 to 100 mol% of ethylene or a copolymer of ethylene with at least one or more kinds of α-olefins other than ethylene. Claim 7
The manufacturing method described in paragraph. 9. The high density polyethylene of the core layer constituting the composite sheet has an MFR ₂ (190 ° C.) of 2 to 20, and a density of 0.9.
The manufacturing method according to claim 6, wherein the amount is 6 to 0.98 g / cc. 10. MFR ₁₀ (190 ° C.) / M of high-density polyethylene
FR ₂ (190 ° C) is 1-10, The manufacturing method of Claim 9 characterized by the above-mentioned. 11. A composite sheet obtained by laminating simultaneously both outer layers made of a solidified propylene-based polymer on both sides of a core layer made of high-density polyethylene in a fusible state as a raw material. The manufacturing method according to claim 6, characterized in that: