SE466646B - PRINTABLE CONTAINER IMAGE OF LAMINATE CONTAINING LAYER OF A FLUORO POLYMER AND A METAL FOLY LAYER - Google Patents

Description

20 25 30 35 466 646 has actually been found to be the case with fluoridine-containing toothpastes. Another disadvantage of a plastic tube lies in the inability of the surface to easily absorb prints or decorative materials. In addition, plastic tubes of, for example, polyethylene have a memory effect, i.e. they do not remain compressed after being squeezed, which is particularly disadvantageous for toothpaste tubes.

To address these problems, it has thus been proposed to provide a metal foil barrier between the product and the polyethylene tube body. This would counteract the compressibility problem by the metal layer transferring its compressibility to the plastic. In addition, the metal foil barrier between the product and the polyethylene tube body would prevent said loss of essential oils and oxygen absorption. The metal barrier has been proposed as an intermediate layer between external polyethylene layers, and it has also been suggested that a laminate should be formed by heat with or without suitable adhesives. While a structure 'with. this general composition effectively prevents some product permeation and oxygen absorption through the tip body, and especially when the inner thermoplastic layer is a copolymer of ethylene and a monomer containing a polar group, which monomer is copolymerizable therewith, however, the risk of product decomposition remains, let alone significantly less.

The following prior art should be considered.

As disclosed in U.S. Patent No. 3,295,725, Brandt has developed a tube which combines the above advantages of an aluminum tube with the advantages of a plastic tube. This is a laminated collapsible dispensing container containing both a metal barrier and an inner polyethylene wall. The thermoplastic layer is generally described as a polyolefin and a copolymer of an olefin and a monomer containing a polar group, which monomer is copolymerizable with the olefin. This laminate overcomes the limitations described above with the exception of absorption of the essential oils from the dentifrices.

According to Canadian Patent No. 728,525, Marchak also developed a laminated tube containing an inner layer of polyethylene. He observed the problem of absorption of flavoring oil through the thermoplastic wall.

Other inventors have investigated surface treated polymers in their manufactured articles. D'Angelo, U.S. Patent No. 4,142,032 noted in studies of films and containers that barrier properties are improved by surface treatment with both fluorine and bromine. However, he did not manufacture a tube, his article did not contain aluminum and he did not note the taste barrier properties of his polymer.

Boultinghouse (U.S. Patent No. 4,292,151), Gilmour (U.S. Patent No. 4,110,518), Dixon (U.S. Patent No. 4,020,223), Scotland (U.S. Patent No. 3,647,613) and Anand (U.S. Patent No. 4,404,256) also had articles prepared comprising fluoride-treated polymers. Boultinghouse demonstrated that the treatment made the surfaces receptive to adhesives, coatings, paints, inks, decorations and the like, Gilmour showed that the surface acted as an electrical insulator, Dixon's treatment imparted oil stain release properties, Scotland's treatment achieved solvent resistance.

However, none of these articles were tubes, no articles contained an aluminum layer, and none of the inventors noted the taste resistance of these articles.

Thus, compressible dispensing containers for pasty material, such as toothpaste, are known whose container wall comprises a laminate formed of four layers, the third, second outermost layer consisting of paper. 10 15 20 25 30 35 466 646 Ett. An important object of the present invention is to provide improved dispensing containers with respect to, among other things, storage stability. This object is fulfilled by an artificial discharge container of the type described above, the first innermost layer and the fourth outermost layer of the container wall consist of fluorinated polyethylene and the second, second innermost layer consists of metal foil as a gas barrier.

Additional layers include paper and suitable adhesives and adhesives such as copolymer of ethylene and acrylic acid.

The compressible dispensing container of the present invention may be constructed of the laminated substrate of the present invention by conventional and known apparatus. Examples of such equipment and methods of manufacture can be read from U.S. Patent No. 3,832,964 which is incorporated herein by reference. Additional objects and advantages of the invention will become apparent from the following description.

In the drawings, Fig. 1 shows a cross-sectional view of a portion of a laminated substrate according to the present invention, and Fig. 2 is a side view of a compressible dispensing container formed in accordance with the invention, with portions of the walls cut away to more fully illustrate it. laminated structure.

The thermoplastic of the present invention is fluorinated polyethylene. Fig. 1 of the drawing shows a substrate 10 in cross section, for 5 .. 10 15 20 25 30 35 466 646 to illustrate the components of the sandwich structure constituting the laminated configuration.

It can be seen from this that the bottom layer 11 is a fluorinated polyethylene. The second layer 12 above this is an adhesive layer which connects the fluorinated polyethylene layer 11 to a third layer 13, which is a metal foil such as an aluminum foil. The fourth layer 14 is another adhesive layer which binds the surface of the metal foil layer 13 to a paper layer 15. The top layer 16 is fluorinated polyethylene. The fluorinated polyethylenes are particularly useful as they have very low flavor absorption properties, as shown by the following tables, where fluorinated polyethylenes are compared to polyethylene, where the thicknesses of the layers or coating are the same: Table I Relative flavor absorption in polymers from flavored dentifrice * Aluminum 0.4 0 0.4 Fluoride-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-O (Air Products) 100 94 lll * All figures relate to the low density polyethylene at 22 ° C, which is arbitrarily set to 100: the lower the figure, the less flavor is absorbed. 10 15 20 25 30 466 646 Table II Neat Flavor Oil Absorption% Aluminum 0 Fluoride-treated high-density polyethylene HD-3 (Air Products) 3.3 High-density polyethylene HD-0 (Air Products) 4.8 Low-density polyethylene LD -0 (Air Product) 7.9 Low Density Polyethylene NA (USI) 10.0 Jonomer Surlyn 1707 (DuPont) 15.7 Jonomer Surlyn 1605 (DuPont) 19.0 Jonomer Surlyn 1706 (DuPont) 24.3 Table III Powder Absorption of Clove fi a ( Neat Flavor Oil) o \ ° absorbed flavor no. 74 fluorine-surface-treated low-density polyethylene (a) 2.6 Nr. 76 fluorinated surface-treated low-density polyethylene (a) 2.6 Low-density polyethylene (b) 5.5 Low-density polyethylene (control) (a) 5,6i0,14 (e) Ionomer (c) 7.4 Ionomer (d) 12,2 15 20 25 30 35 466 646 (a) The low density polyethylene is Lupole l804H (BASF (b) Tenite 154 (Eastman) (c) Surlyn 8940 (DuPont) (d) Syrlyn 8920 (DuPont) (e) n = 3 ïabell IV Loss of Flavor from flavored dentifrice to polymers' Loss of flavor * No. 76 fluorine-surface-treated low-density polyethylene (a) 56 No. 74 fluorine-surface-treated low-density polyethylene (a) 64 Ionomer (b) 88 Ionomer (c) 96 Low-density polyethylene (control) ) (a) 100 Low density polyethylene (d) - 136 * Relative BASF low density polyethylene control arbitrarily set to 100; the lower the number, the lower the flavor loss from the dentifrice. (a) LPDE is Lupole 1804H (BASF) (b) Surlyn 8920 (DuPont) (c) Surlyn 8940 (DuPont) (d) Tenite 154 (Eastman) It is contemplated that within the scope of the invention the binders are a copolymer of ethylene and acrylic acid or methacrylic acid. or sodium or zinc salts thereof in a solvent system. The metal foil is preferably an aluminum foil.

The paper layer is suitably a kraft paper.

The thickness range for each of the layers is as follows: The fluorinated polyethylene layer 11 - 0.012? 0.0762 mm, preferably 0.0254 mm.

The adhesive layer 12 - sufficient to ensure adhesion.

The metal foil layer 13 - 0.0127 - 0.0508 mm, preferably 0.0254 mm.

The adhesive layer 14 - sufficient to ensure adhesion.

Paper layer 15 - 0.0381 - 0.063l mm, 0.0508 mm. preferably The fluorinated polyethylene layer 16 - 0.0889 - 0.127 mm, preferably 0.1016 mm.

The top fluorinated polyethylene layer 16 adheres to the paper layer 15 by applying sufficient heat and sufficient pressure to the substrate. In case the heat supply and application of pressure is not suitable, a suitable binder must be used.

Figure 2 is an example of the laminated structure of a compressible container with the layers shown as in Figure 1 with the layer 11 at the bottom and the other layers consisting of the same material and in the same order as shown.

W <1 10 15 20 25 30 35 466 646 From the above it appears that the invention provides a collapsible container structure which substantially reduces the hitherto unresolved problems of the prior art. The laminated substrate and the laminated shoulder piece 20 substantially completely eliminate product permeation and oxygen absorption.

The outer layer consisting of a fluorinated polyethylene is a thermoplastic that can be melted during a side bonding step and provides protection for the intermediate paper and metal foil layers. The technique of sealing a compressible toothpaste tube of the type generally described herein is disclosed in U.S. Patent No. 3,295,725, which is incorporated herein by reference.

When the outermost and innermost layers are the same, which is preferred, the folded edges of the tube made of the substrate can be conveniently heat bonded. A suitable binder can be used when heat connection is not possible. This modification is one. complement to the previously mentioned four-layer laminate, which seen from the outside in consists of fluorinated polyethylene, paper, foil and fluorinated polyethylene.

It is intended that suitable adhesives be used between the laminate layers as soon as this is necessary. Fluorinated polyethylene can also be used for the shoulder piece, the cap, the neck piston and in the design of discharge valves for other dentifrice discharge devices, especially in connection with the inner parts which are exposed to the enclosed dentifrice, and again, when required, compatible binders are of course used.

When cast as a film on the inner surfaces of fibrous drums used for storing flavored dentifrice, the material further delays flavor loss to the drums, thereby extending shelf life.

Various modifications of the invention have been described, and these and other changes may, of course, be made without departing from the scope of the invention.

Claims (4)

10 15 20 466 646 ll P a t e n t k r a v A squeezable dispensing container for pasty material, such as toothpaste, the container wall comprising a laminate formed of four layers (11, 13, 15, 16), the third, second outermost layer (15) consisting of paper, characterized in that the first innermost layer (11) and the fourth outermost layer (16) consist of fluorinated polyethylene and that the second, second innermost layer, (13) consists of metal foil as a gas barrier. Container according to claim 1, characterized in that the first layer of fluorinated polyethylene is connected to the metal foil by means of a binder (12). Container according to claim 1 or 2, characterized in that the third layer of paper (15) is connected to the fourth layer (16) of the fluoropolymer by means of an adhesive. Container according to Claim 2 or 3, characterized in that the binder (12) is a copolymer of ethylene and acrylic acid.