NL8503546A - LAMINATED SUBSTRATE AND ARTICLE MADE THEREFROM INCLUDING FLORORATED POLYETHYLENE. - Google Patents

Description

ί «VO 7546

Laminated substrate and article made therefrom incorporating fluorinated polyethylene.

The present invention relates generally to the technique of manufacturing containers and more particularly relates to a collapsible administration container having a laminated wall construction in its body portion, permeation and absorption of product, as well as oxygen absorption in all, previously sensitive areas of the container structure are substantially prevented.

Collapsible tubes made of metal and plastic materials have long been known in the field of packaging.

Extruded metal tubes are brittle by nature and repeated use often results in wall cracks so that product is separated from a location other than the substantially rigid delivery opening.

Of the metal tubes known in the art, aluminum tubes, although probably the least brittle, are somewhat limited in their applications, as hitherto it has not been possible to obtain a completely satisfactory coating on the internal surfaces thereof. when required to prevent attack and corrosion of the metal by an alkaline or acidic content and contamination of the content by the reaction products. Despite the relatively brittle nature of a metal tube, the said internal coating operation necessitates an additional processing step, which necessarily increases the price of the final article.

Tubes formed from polyethylene and other plastics have enjoyed widespread commercial success in packaging many products; however, when certain other products were contained therein, these were found to deteriorate in time. Plastics, such as, for example, polyethylene, are permeable to some degree when used in the wall thicknesses used for tubular containers, and of the essential oils contained in most flavoring dentifrices, the volume during storage the holder smaller, making it ï -; 3 4 Ö 5 -2- dentifrice becomes less pleasant in taste. Also the container wall made of plastic absorbs during a. oxygen for a certain period of time and can finally decompose the product, which has been found to be the case with fluoride containing toothpastes.

Another drawback of the plastic tube lies in the inability of the surface to easily absorb printing material or decorative material. In addition, plastic tubes, for example, those made of polyethylene, have a memory effect; that is, when squeezed, they do not remain compressed, which is a particular drawback for dentifrice tubes.

To counteract the above-mentioned problems, it has therefore been proposed to provide a metal foil as a barrier between the product and the polyethylene tube body. This would counteract the compressibility problem in that the metal layer 15 would impose its compressibility on the plastic. In addition, the metal foil barrier between the product and the polyethylene tube body would prevent said essential oil loss and oxygen absorption. It has been proposed to design the metal barrier as an intermediate layer between coating layers of polyethylene and to laminate it by heat with or without suitable adhesives. However, although a structure of this general character is effective in preventing any product permeation and oxygen absorption through the tube body, and especially when the inner thermoplastic layer 25 is a copolymer of ethylene and a copolymerizable monomer having a polar group, the possibility of product decline remains, although to a much lesser extent.

Attention is drawn to the following prior art: In the U.S. U.S. Patent 3,295,725 discloses a tube combining the advantages of an aluminum tube with the advantages of a plastic tube. This tube is a laminated collapsible administration container containing both a metal barrier and a polyethylene inner wall. The thermoplastic layer is generally described as consisting of polyolefin and a copolymer of an olefin and a polar group-containing monomer which is copolymerizable therewith. This laminate overcomes the above-described limitations, except for the absorption of the essential oils from the dentifrices.

Canadian Patent 728,525 also describes the development of a laminated tube containing an inner layer of poly-ethylene, recognizing the problem of flavor oil absorption through the thermoplastic wall.

According to another patent publication, surface treated polymers have been investigated for the articles made therefrom. With regard to the investigation of films and holders, according to the US U.S. Patent 4,142,032 noted that the barrier properties are improved by surface treatment with both fluorine and bromine.

However, no tube was manufactured for this; the object had no aluminum; and the properties of this polymer as a flavor barrier 15 were not recognized.

At the U.S. Pat. Nos. 4,2926,151, 4,110,518, 4,020,223, 3,647,613 and 4,404,256 also concerned manufactured articles involving polymers whose surface had been treated with fluorine.

In the former of these patents it is shown that the treatment made the surfaces susceptible to adhesives, coatings, paints, inks, decorations and the like; in the U.S. U.S. Patent 4,110,518 shows that the surface behaves like an electrical insulator; in the treatment according to the U.S. U.S. Pat. No. 4,020,223 granted oil spill release properties; the treatment of U.S. Patent 3,647,613 provided solvent resistance. None of these objects, however, were tubes; none of these objects contain an aluminum layer; and none of these patents disclose the flavor resistance of these articles.

It is therefore an important object of the present invention to provide a collapsible administration container with a laminated wall construction in the body portion.

Another object of the invention is to provide a tubular container, in the body portion of which there are a plurality of adhesive layers, one of said layers of which is a barrier against product migration and oxygen absorption.

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* -4- provided, such as a metal foil, and another of said layers consists of a fluorinated polyethylene or mixture thereof, which varies in density and crystallinity. The latter layer is used as the innermost layer and preferably also as the outer layer 5, with various additional laminae arranged in between.

Such additional layers include paper and suitable adhesives and adhesives such as a copolymer of ethylene and acrylic acid.

The collapsible administration container of the present invention can be constructed from the laminated substrate 10 of the present invention by conventional and known devices. Examples of such an installation and method can be found in US. U.S. Patent 3,832,964.

Another object of the present invention is to provide a method for the production of laminated tubes, whereby a tubular body is formed from a barrier layer and a fluorinated polyethylene laminated thereto; the laminated tube body is then placed on a molding element next to a barrier element also thereon.

Other objects and advantages of the invention will become more apparent as the description progresses.

In the drawings, in which the same numbers are always used to indicate the same parts. Fig. 1 is a cross-sectional view of a fragmentary portion of a laminated substrate according to the present invention; FIG. 2 is a side view of a collapsible administration container embodying the novel views of the present invention, with the parts of the body walls broken away to more fully illustrate the laminated structure.

The thermoplastic material of the present invention is fluorinated polyethylene.

Reference is now first made to Fig. 1 of the drawings in which a substrate 10 is shown in cross-section, revealing the components of the sandwich which will assemble the laminated configuration.

It will be understood that the bottom layer 11 consists of a fluorinated polyethylene. The superimposed second layer 12 is an adhesive layer which bonds the fluorinated polyethylene layer 11 to the third layer 13 which is a metal foil, such as aluminum foil. The fourth layer 14 again consists of an adhesive which adheres the other surface of the metal foil layer 13 to a paper layer 15. The top layer 16 is made of fluorinated polyethylene.

The fluorinated polyethylenes are particularly suitable because they have very weak flavor absorption characteristics, as can be seen from the following tables comparing fluorinated polyethylenes with polyethylene, the thicknesses of the layers or coating being the same:

10 TABLE A

Relative flavor absorption in flavor-containing polymeric dentifrice k__

22.2 ° C 32.2 ° C 48.9 ° C

Aluminum 0.4 0 0.4 15 High density polyethylene that has been surface treated with fluorine 22 37 90 HD-3 (Air Products)

High density polyethylene 20 HD-0 (Air Products) 98 94 100

Low Density Polyethylene LD-0 (Air Products) 100 94 111 x All numbers relative to Low Density Polyethylene at 22.2 ° C arbitrarily set to 100; the lower the number, the less flavor is absorbed.

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TABLE B

Polymer absorption of uncut flavoring oil

Absorption (%)

Aluminum 0

High density polyethylene, the surface of which was treated with fluorine HD-3 (Air Products) 3.3.

5 High density polyethylene HD-0 (Air Products) 4.8

Low density polyethylene LD-0 (Air Products) 7.9

Low density polyethylene 10 NA (USI) 10.0 lonomer

Surlyn 1707 (DuPont) 15.7 lonomer

Surlyn 1605 (DuPont) 19.0 15 lonomer

Surlyn 1706 (DuPont) 24.3 -, - · -J / -¾ Q} U 0 0} 0 -7-

TABLE C

Polymer absorption of uncut flavoring oil% absorbed flavoring

Low-density polyethylene, the surface of which has been treated with fluorine, No. 74 2.6

Low-density polyethylene, the surface of which is treated with fluorine, No. 76, 2.6

Low density polyethylene1 5.5 10 Low density polyethylene (control) ^ 5.6 _ + 0.14 ^ (c)

Ionomer 7.4

Ionomer ^ 12.2 (a) The low density polyethylene is Lupolen 1804H (BASF) (b) Tenite 154 (Eastman) 15 (c) Surlyn 8940 (DuPont) (d) Surlyn 8920 (DuPont) (e) n = 3

TABLE D

Loss of flavor from a dentifrice-containing dentifrice due to absorption into the polymers

Flavor loss x 20 -

Low-density polyethylene, the surface of which has been treated with fluorine, No. 76 56

Low density polyethylene, 25 of which are surface treated with fluorine, No. 74 64

Ionomer ^ 88 (o)

Ionomer 96

Low density polyethylene (control) ^ 100

Low density polyethylene 136 30 * Relative to low density polyethylene (BASF) (control), the loss of which is arbitrarily set at 100; the lower the number, the less flavor loss from the dentifrice.

«Γ · -δία) _LDPE is Lupolen 1804 (BASF) (b) Surlyn 8920 (DuPont) (c) Surlyn 8940 (DuPont) (d) Tenite 154 (Eastman) 5 It has been taken into account that under the The glues may be a copolymer of ethylene and acrylic acid or methacrylic acid, or sodium or zinc salts thereof in a diluent system.

The metal foil is preferably aluminum foil.

It is desirable that the paper layer consists of kraft paper.

The thickness range of each of the layers is as follows: Fluorinated polyethylene layer 11: 0.0127 mm to 0.0762 mm, preferably 0.0254 mm.

Bonding layer 12: sufficient to ensure bonding. Metal foil layer 13: 0.0127 mm to 0.0508 mm, preferably 0.0254 mm.

Bonding layer 14: sufficient to ensure bonding. Paper layer 15: 0.0381 mm to 0.0635 mm, preferably 0.0508 mm. Fluorinated polyethylene layer 16: 0.0889 mm to 0.1270 mm, preferably 0.1016 mm.

The upper fluorinated polyethylene layer 16 is adhered to the paper layer 15 by applying sufficient heat and pressure to the substrate. In the event that application of heat and pressure is not suitable, a suitable adhesive must be used.

Fig. 2 is an example of the laminated structure of a collapsible container, wherein the layers "are shown as in FIG. 1 with layer 11 as the innermost and the other layers are the same materials and are in the same order as shown herein .

It is believed that it is clear from the foregoing that Applicant has provided a collapsible container structure which substantially reduces the problems solved hitherto. The laminated substrate and the laminated shoulder pad 20 substantially eliminate product permeation and oxygen absorption.

O /. ^ * * 3 -9- -. A fluorinated polyethylene outer layer is a thermoplastic layer that can melt during a side-summer step and provide adequate protection to the paper interlayer and metal foil interlayer. The zoom technique on a collapsible dentifrice tube of the general type described herein can be performed on the U.S. No. 3,295,725 are derived.

However, the fluorinated polyethylene and paper outer layer can be eliminated if the film barrier has sufficient thickness to resist damage, and to flow a thermoplastic material into the wrap-over seam during welding when such a system is used.

Furthermore, in a three-layer laminate formed of paper, foil and fluorinated polyethylene in the manner described, the outer layer may be of paper. Since the outer and inner layers preferably consist of the same material, the folded edges of the tube made of the substrate are easily heat-bonded together. A suitable adhesive can be used when heat-bonding is not possible. This modification is an additional modification in addition to the aforementioned four-layer laminate, consisting of fluorinated polyethylene from the outside to the inside, paper, foil and fluorinated polyethylene.

It has been taken into account that suitable adhesives will be used between the laminae if necessary.

Fluorinated polyethylene can also be used for the yoke, cap, neck, plunger and in the construction of delivery valves for other dentifrice delivery devices, particularly in connection with the internals contained therein dentifrice and, again, compatible adhesives 30 will of course be used where required.

Moreover, when the material is cast as a film on the inner surfaces of fiber drums used for storage of a dentifrice, to which flavoring has been added, that material will retard the loss of flavor within the grout, thereby increasing the storage time. extended.

Several modifications of the invention have been described herein, and these and other modifications can of course be accomplished

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Claims (10)

1. Sen substrate of layers of materials. comprising: a first layer of a fluorinated polyethylene, a second layer of metal foil, a third layer of paper and a fourth layer of a fluorinated polyethylene. The substrate according to claim 1, wherein the first layer of the fluorinated polyethylene is attached to the metal foil with an adhesive. The substrate according to claim 1 or 2, wherein the third layer of paper is attached to the fourth layer of the fluorinated polyethylene with an adhesive. The substrate according to any one of claims 1 to 3, wherein the first layer of the fluorinated polyethylene is attached to the metal foil with an adhesive and wherein the third layer of paper is attached to the fourth layer of the fluorinated polyethylene with an adhesive. The substrate according to claim 4, wherein the adhesive is a copolymer of ethylene and acrylic acid. 6. A collapsible paste administration container, consisting of layers of materials and comprising: a first, inner layer of fluorinated polyethylene, a second layer of metal foil, a third layer of 20 paper and an outer, fourth layer of a fluorinated polyethylene . The container according to claim 6, wherein the first layer of the fluorinated polyethylene is attached to the metal foil with an adhesive. The container according to claim 6 or 7, wherein the third layer of paper 25 is attached to the fourth layer of the fluorinated polymer with an adhesive. The container according to any one of claims 6r8 / wherein the first layer of the fluorinated polyethylene is attached to the metal foil with an adhesive, and wherein the third layer of paper is attached to the fourth layer of the fluorinated polyethylene with an adhesive. The container according to claim 9, wherein the adhesive is a copolymer of ethylene and acrylic acid. . - * .- »** · * f Ή ·: f'- V ** r i v