CH669560A5 - - Google Patents

Description

DESCRIPTION

The present invention relates to a laminate and a paste dispenser container made from this laminate and in particular to compressible dispensers, the container part of which is formed from laminated walls, product permeation and absorption and oxygen absorption being substantially suppressed in all areas of the container which are susceptible to this.

Compressible tubes made of metal or plastic have long been known in the packaging sector. Tubes made of extruded metal are fragile and prolonged use often leads to wall breaks, so that the goods emerge from a location other than the essentially rigid dispenser opening. Of the known metal tubes, aluminum tubes, which are probably the least brittle, are limited in their area of application, since until now it has not been possible to apply a really satisfactory coating to their inner surfaces if it was necessary to attack and corrode the metal to prevent alkaline or acidic ingredients and contamination of the content by the reaction products. In addition to the relatively fragile nature of a metal tube, the inner coating mentioned requires an additional manufacturing step, which necessarily increases the price of the finished article.

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Tubes made of polyethylene and other plastics are used to package many materials; it has been observed that certain goods spoil after some time in such packaging. Plastics such as polyethylene are 5 permeable to a certain extent if they are used in the wall thicknesses used for tubular containers. The essential oils contained in most flavoring toothpastes decrease in volume during storage of the container, making the toothpaste less tasty. Furthermore, the wall of the plastic container absorbs oxygen over time, and finally the product decomposes, which has indeed been observed with toothpastes containing fluoride. Another disadvantage of the plastic tube is that its surface is not able to accommodate 15 additional printing or decorative material. Furthermore, plastic tubes, such as those made of polyethylene, have a memory effect; i.e. that they do not remain compressed after squeezing, which is particularly disadvantageous for toothpaste tubes.

20 In order to counter the problems mentioned above, it was accordingly proposed to provide a metal foil barrier layer between the goods and the polyethylene tube body. The compressibility problem is countered by the fact that the metal layer transfers its compressibility to the plastic. Furthermore, the metal foil barrier layer between the goods and the polyethylene tube body prevents the aforementioned loss of essential oils and the absorption of oxygen. The metal barrier layer has been proposed as an intermediate layer between adjacent polyethylene films, and a laminate is to be formed by heat with or without suitable adhesives. Although a structure of this general type has the effect of preventing to some extent product permeation and oxygen absorption through the tube body, this is especially true when the inner thermoplastic layer is a copolymer of ethylene and a polar group-containing monomer which is associated with the former is copolymerizable. Nevertheless, the possibility of decomposing the goods remains, albeit to a much lesser extent. 40 A tube is described in US Pat. No. 3,295,725 in which the above-mentioned advantages of an aluminum tube are combined with the advantages of a plastic tube. It is a laminated compressible dispenser container that includes both a metal barrier and a polyethylene inner wall. The thermoplastic layer is roughly described as a polyoleon and copolymer of an olefin and a monomer containing copolymer that can be copolymerized therewith. With this laminate the limitations described above with the exception of the absorption of the essential oils from the toothpastes are overcome.

A laminated tube is known from CA-PS 728 525, which contains an inner layer made of polyethylene. The problem of absorption of flavor oil through the thermoplastic wall is discussed.

55 According to other patent applications, surface-treated polymers were examined in the respective products. According to US Pat. No. 4,142,032, tests on foils and containers have shown that the barrier properties are improved by surface treatment with both fluorine and with 60 bromine. However, the production of a tube is not described; the product has no aluminum; and the flavor blocking properties of the polymer were not recognized.

Also in US Pat. Nos. 4,296,241,4110,518.4,020,223.3,647,613,665 and 4,440,256 products are described which comprise fluorine-treated polymers on the surface. US Pat. No. 4,229,251 shows that the surfaces can be absorbed by the treatment for adhesives, coatings, paints, inks,

Decorations and the like. US Pat. No. 4,110,518 shows that the surface behaves as an electrical insulator. The treatment according to US Pat. No. 4,020,223 imparts properties which prevent oil stains. The treatment according to US Pat. No. 3,647,613 creates resistance to solvents. None of the products described is a tube; none contains an aluminum layer; and in no case was the resistance to flavors of these products recognized.

It is therefore an important object of the present invention to provide a compressible dispenser container whose body has a laminated wall structure.

Another object of the invention is to provide a tubular container with a plurality of mutually adhesive layers in the body thereof, one of these layers, such as a metal foil, being a barrier against product migration and oxygen absorption and another of these layers being a fluorinated polyethylene or Mixture of different density and crystallinity. The latter layer forms the inner layer and preferably the outer layer, with various further laminate layers being arranged between them.

These further layers include paper and suitable adhesives and binders, e.g. B. a copolymer of ethylene and acrylic acid.

The compressible dispenser according to the invention can be produced from the laminate film according to the invention using conventional and known apparatus. Examples of such an apparatus and such a method can be found in US Pat. No. 3,832,964, which is hereby incorporated by reference into the present description.

A method of manufacturing laminated tubes has also been created in which a tube body is made from a barrier layer and a fluorinated polyethylene laminated thereon; the laminated tube body is then brought together on a molded part with a barrier part also located thereon.

The invention is explained in more detail below with reference to figures, in which the same numerals always mean the same parts; show it:

1 shows a cross section through a piece of a laminate according to the invention, and

2 shows a side view of a compressible dispenser container according to the invention, which embodies the new concept according to the invention, parts of the container wall being removed in order to make the laminate structure visible.

The thermoplastic according to the invention is a fluorinated polyethylene.

Referring first to FIG. 1, a substrate 10 is shown in cross section, thereby exposing the components of the sandwich structure that make up the laminate assembly.

It can be seen that the bottom layer 11 is a fluorinated polyethylene. The second layer 12 above is an adhesive layer that connects the layer of fluorinated polyethylene to the third layer 13, which is a metal foil such as an aluminum foil. The fourth layer 14 is a further adhesive that adhesively attaches the other surface of the metal foil layer 13 to a paper layer 15. The top layer 16 is a fluorinated polyethylene.

The fluorinated polyethylenes are particularly suitable because they show very poor taste absorption properties, as can be seen from the following tables, in which fluorinated polyethylenes are compared with polyethylene, the thicknesses of the layers or coatings being the same.

669 560

Table I

Relative flavor absorption by polymers from flavored toothpaste

22 ° C

32 ° C

49 ° C

aluminum

0.4

0

0.4

On the surface with

Fluorine treated

High density polyethylene

HD-3 (Air Products)

22

37

90

High density polyethylene

HD-0 (Air Products)

98

94

100

Low density polyethylene

LD-0 (Air Products)

100

94

111

All numbers refer to low density polyethylene at 22 ° C which was arbitrarily set to 100; the smaller the number, the less flavoring agent has been absorbed.

Table II

Absorption of undiluted flavor oil by polymers

Absorption(%)

aluminum

0

Poly treated with fluorine on the surface

high density ethylene

HD-3 (Air Products)

3.3

High density polyethylene

HD-0 (Air Products)

4.8

Low density polyethylene

LD-0 (Air Products)

7.9

Low density polyethylene

NA (USI)

10.0

Ionomer

Surlyn 1707 (Du Pont)

15.7

Ionomer

Surlyn 1605 (Du Pont)

19.0

Ionomer

Surlyn 1706 (Du Pont)

24.3

Table III

Absorption of undiluted flavor oil by polymers

% flavor absorbed

No. 74, surface treated with fluorine

Low density polyethylene (a) 2.6 No. 76, surface treated with fluorine

Low density polyethylene (a) 2.6

Low density polyethylene (b) 5.5 Low density polyethylene

(Comparative test) (a) 5.6 ± 0.14 (e)

Ionomer (c) 7.4

Ionomer® 12.2

(a) The low density polyethylene was Lupolen 1804H (BASF)

(b) Tenite 154 (Eastman)

(c) Surlyn 8940 (Du Pont)

(d) Surlyn 8920 (Du Pont)

(e) n = 3

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669 560

Table IV

Loss of flavoring from flavored toothpaste to polymers

Flavor loss *

No. 76, surface treated with fluorine

Low density polyethylene (a) 56 No. 74, surface treated with fluorine

Low density polyethylene (a) 64

Ionomer (b) 88

Ionomer (c) 96 low density polyethylene

(Comparative experiment) (a) 100

Low density polyethylene (d) 136

* Based on BASF's low density polyethylene, which was arbitrarily set to 100; the smaller the number, the less the loss of flavor from toothpaste.

(a) The low density polyethylene was Lupolen 1804H (BASF)

(b) Surlyn 8920 (Du Pont)

(c) Surlyn 8940 (Du Pont)

(d) Tenite 154 (Eastman)

According to the invention, the adhesive can be a copolymer of ethylene and acrylic acid or methacrylic acid or their sodium or zinc salts in a diluent system. The metal foil is preferably aluminum foil. The paper layer is preferably wrapping paper. The respective thickness of the layers is in the range from: 12.7 [x to 76.2 | x, preferably 25.4 | x for the layer 11 made of fluorinated polyethylene,

sufficient thickness to ensure adhesion for the adhesive layer 12,

12.7 fx to 50.8 | x, preferably 25.4 | x for the metal foil layer 13,

sufficient thickness to ensure adhesion for the adhesive layer 14,

38.1 jx to 63.5 u, preferably 50.8 ix for the paper layer 15 and

88.9 [x to 127.0 | x, preferably 101.6 for layer 16 of fluorinated polyethylene.

The top layer 16 of fluorinated polyethylene adheres to the paper layer 15 by applying enough heat and pressure to the laminate. If the application of heat and pressure is not appropriate, a suitable adhesive is used.

Fig. 2 shows an example of a compressible container made of the laminate, in which, as shown in Fig. 1, the layers! where layer 11 is the innermost layer and the other i layers consist of the same materials in the same order i as shown in FIG. 1.

The compressible container according to the invention eliminates the disadvantages mentioned in the prior art; overcome. The laminated container body and the laminated shoulder piece 20 completely prevent product blocking and j oxygen absorption. ,

The outer layer consists of a fluorinated polyethylene. Made of a thermoplastic material that can be welded at the side seam formation level and that offers adequate protection for the paper and metal foil intermediate layer. Seam j in a compressible toothpaste tube of the general type described here i is described in US Pat. No. 3,295,725, which is hereby incorporated by reference into this description. The outer layer! fluorinated polyethylene and paper can be omitted if the barrier film is of sufficient thickness to: resist damage; in this case a thermoplastic material is introduced into the overlapping seam area when it is welded. ]

Furthermore, with a three-layer laminate made of paper, metal foil and a fluorinated polyethylene as described? the outer layer is made of paper. Since the outermost and the innermost layers are preferably the same, the Fait-! edges of the tubes produced are conveniently heat-welded. A suitable adhesive can be used

if heat welding is not possible. This modification j is added to the four-layer laminates mentioned above, from the outside in, fluorinated polyethylene, paper, film j and fluorinated polyethylene. |

Suitable adhesives are used between the laminate layers i if necessary. j

Fluorinated polyethylene can also be used for the shoulder piece, the) cap, the neck, the piston and the structure of the dispenser valve or for other toothpaste dispensers, in particular in connection with the inner parts of the toothpaste in the container exposed, and here too, of course, if necessary, suitable adhesives can be used.

If the material according to the invention is applied as a film to the inner surfaces of the drums made of fiber material used for storing the flavored toothpastes; then the material according to the invention slows down the! Loss of flavors in the drums and thereby increases the storage stability. ]

Various modifications of the invention have been disclosed; beard, and these and other changes can be made! without departing from the new concepts of the invention. !

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1 sheet of drawings

Claims (10)

669 560 PATENT CLAIMS 1. Laminate, characterized by a first layer (11) made of a fluorinated polyethylene, a second layer (13) made of metal foil, a third layer (15) made of paper and a fourth layer (16) made of a fluorinated polyethylene. 2. Laminate according to claim 1, characterized in that the first layer (11) made of fluorinated polyethylene is attached to the metal foil (13) with an adhesive (12). 3. Laminate according to claim 1, characterized in that the third layer (15) of paper is attached to the fourth layer (16) made of fluorinated polyethylene with an adhesive. 4. Laminate according to claim 1, characterized in that the first layer (11) made of fluorinated polyethylene is attached to the metal foil (13) with an adhesive and that the third layer (15) made of paper on the fourth layer (16) the fluorinated polyethylene is attached with an adhesive. 5. Laminate according to one of claims 2 to 4, characterized in that the adhesive is a copolymer of ethylene and acrylic acid. 6. Compressible paste dispenser container made of a laminate, characterized by a first inner layer (11) made of a fluorinated polyethylene, a second layer (13) made of metal foil, a third layer (15) made of paper and an outer fourth layer (16) made of a fluorinated one Polyethylene. Container according to claim 6, characterized in that the first layer (11) made of fluorinated polyethylene is attached to the metal foil (13) with an adhesive (12). 8. A container according to claim 6, characterized in that the third layer (15) of paper is attached to the fourth layer (16) of fluorinated polyethylene with an adhesive. A container according to claim 6, characterized in that the first layer (11) made of fluorinated polyethylene is attached to the metal foil (13) with an adhesive and that the third layer (15) made of paper on the fourth layer (16) made of fluorinated polyethylene is attached with an adhesive. Container according to one of claims 7 to 9, characterized in that the adhesive is a copolymer of ethylene and acrylic acid.