SE466645B - PRINTABLE CONTAINER IMAGE OF LAMINATE CONTAINING THERMOPLASTIC AND METAL FOLY LAYERS - Google Patents

Description

466 645 product, which in fact proved to be the case with fluoride-containing toothpastes. Another disadvantage of a plastic tube lies in the inability of the surface to easily receive print or decorative material. In addition, plastic tubes, such as polyethylene tubes, have a memory effect, i.e. they do not remain compressed when compressed, which is a particular disadvantage in the case of toothpaste tubes.

Thus, in order to counteract the above problems, it has been proposed to provide a metal foil barrier between the product and the polyethylene tube body. This would counteract the compressibility problem in that the metal layer would transfer its compressibility to the plastic. In addition, the metal foil barrier between the product and the polyethylene tube body would prevent the said loss of essential oils and oxygen absorption.

The metal barrier has been proposed as an intermediate layer between adjacent layers of polyethylene and that a laminate would be formed by heat with or without suitable adhesives. However, although a structure of this general structure effectively prevents some product permeation and oxygen absorption through the tube 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, the risk remains: for product breakdown, albeit to a much lesser extent.

The following literature is interesting: The Canadian patent no. No. 728,525 discloses a laminated tube containing an inner polyethylene layer. The problem of absorption of essential oil by the thermoplastic wall has been noted and the use of nylon to overcome this problem is proposed. 1546 466 645 U.S.C. patent no. 4, 139,665, which describes a laminate which does not contain metal. Among other things, this laminate uses polypropylene as an inner layer to act as a barrier against moisture and water vapor. A thermoplastic acrylonitrile copolymer acts as a flavor barrier. This laminate differs from the present invention in that it does not contain a metal foil. Furthermore, the function of polypropylene as a flavor barrier has not been noted.

U.S. patent no. No. 3,958,721 discloses a compressible laminated tube which also does not contain a metal layer. Although this tube contains polypropylene, they have not noticed the low permeability to odor and the high resistance to oil produced by the polyvinyl alcohol film.

Thus, a compressible paste dispensing container of bonded layers of material is known. These layers may comprise two thermoplastic layers and an inner metal foil layer.

None of the above references specifies the polypropylene as the inner layer of compressible laminated tubes containing metal foils. In the cases where polyolefins are mentioned, there is no indication of high resistance to absorption of essential flavoring oils. In fact, the problem with polyethylene is its high taste absorption.

It has now surprisingly been found that polypropylene, a chemical closely related to polyethylene, does not substantially absorb flavoring oils. Based on the above-mentioned specific pasta dispensing container, the invention thus provides a pasta dispensing container with improved properties regarding, among other things, the inner layer's resistance to absorption of flavoring oils. The inventive container comprises a first innermost layer of polypropylene, a second second innermost layer of metal foil, a third adjoining layer of paper and a fourth outermost layer of polypropylene.

An important object of the present invention is thus to provide a compressible dispensing container with a laminated wall construction in the body part.

Another object of the invention is to provide a tubular container with a plurality of adhesive layers in its body part, one of said layers providing a barrier to product migration and oxygen absorption such as a metal foil and another of said layers being polypropylene or a copolymer or a mixture that varies in density and crystallinity. The latter layer is arranged internally and externally with various additional laminate layers compressed therebetween.

Such additional layers comprise paper and suitable adhesive and binder 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 with conventional and known apparatus. Examples of such equipment and methods of manufacture are set forth in U.S. Pat. patent no. 3,832,964, which is incorporated herein by reference.

Additional objects and advantages of the invention will become apparent from the following detailed description.

In the accompanying drawings, Fig. 1 is 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 present invention, with portions of the body walls broken away. to more fully illustrate the laminated structure.

The thermoplastic of the present invention is polypropylene.

Referring to Fig. 1 of the drawings, a cross-sectional substrate is shown to show the components of the sandwich structure required to form the laminated structure.

The figure shows that the bottom layer 11 is polypropylene. The second layer 12 above this is an adhesive layer connecting the polypropylene 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, by adhesion, connects the second surface of the metal foil layer 13 to a paper layer 15. The top layer 16 is polypropylene.

Polypropylene is particularly useful in that it has very low aroma absorption properties, as shown in the following tables, where polypropylene is compared to polyethylene, the thicknesses of the layers or coating being the same: 466 64-5 Table I Polymer Absorption of Neat Flavor Oil Polypropylene Tenite 42306 (Eastman) Polypropylene Fl20F (US Steel) Polypropylene FP200F (US Steel) Polypropylene Vestrolen P3200 (Sleeve Plastic) Low Density Polyethylene Tenite 154 (Eaštman) Low Density Polyethylene Lupole l804H (BASF) Absorgtion%, 5, 6i0, l4 f! 466 645 Table II Flavor loss from flavored dentifrice to Qglyggerer Flavor loss * Polypropylene Tenite 4230G (Eastman) 31 Polypropylene F120F (US Steel) 38 Polypropylene F200F (US Steel) 38 Low density polyethylene Lupole 1804H (TenASite 15) ) 130 * Relative BASF low density polyethylene arbitrarily set to 100; the lower the number, the smaller the aroma loss from the dentifrice. 466 645 Table III Relative aroma absorption in polymers from flavored dentifrices *: glo: glo sig Aluminum 0 0 0 Polypropylene FP200F (US Steel) 34 51 55 Polypropylene Fl20 i (U s steel) 55 ss 73 Low density polyethylene 6560 (ARCO) 76 76 83 Low density polyethylene NPE853 (Norchem) 69 76 104 Low density polyethylene Lupolen l804H (BASF) l00il9 l07il4 ll9il0 * All figures are related to BASF low density polyethylene which is arbitrarily set to 100 at 22 ° C; the lower the number, the less aroma is absorbed.

Within the scope of the invention, the binders or adhesives used may be 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 aluminum foil.

The paper layer is preferably a kraft paper.

The thickness range for each of the layers is as follows: 466 645 Polypropylene layers 11 - 0.012? 0.0762 mm, preferably 0.0254 mm.in Adhesive layer 12 - sufficient to ensure adhesion.

Metal foil layer 13 - 0.012? 0.0508 mm, preferably 0.0254 mm.

Adhesive layer 14 - sufficient to ensure adhesion.

Paper layer 15 - 0.038l - 0.0631 mm, preferably 0.0508 mm.

Polypropylene layer 16 - 0.0889 - 0.127 mm, preferably 0, 1016 mm.

The top polypropylene layer 16 adheres to the paper layer 15 by applying sufficient heat and pressure to the substrate. In case the application of heat and pressure is not suitable, a suitable adhesive can be used. Figure 2 is an example of the laminated structure of a collapsible container with the layers demonstrated as in Figure 1, the layer 11 being the innermost layer and the other layers consisting of the same material and in the same order as shown.

From the above it should be apparent that the applicant provides a collapsible container structure which considerably reduces the hitherto unresolved problems in the prior art. The laminated substrate and a barrier shoulder piece substantially completely eliminate product permeation and oxygen absorption. 466 645 The outermost layer of a polypropylene is a thermoplastic that can be fused together during a side bonding step to ensure adequate protection of the paper and metal foil intermediate layers. The technique of sealing a compressible dentifrice tube of the general type herein is disclosed, for example, in U.S. Pat. patent no. 3,295,725, which is incorporated herein by reference.

Since the outermost and innermost layers are preferably the same, the folded edges of the tube produced from the substrate can be conveniently heat bonded. A suitable adhesive can be used when heat connection is not possible. This modification is a complement to the above-mentioned four-layer laminate consisting of, seen from the outside and in, polypropylene, paper, foil and polypropylene. Suitable adhesives or adhesives can be used between the laminate layers as soon as this is necessary.

Polypropylene can also be used for the shoulder piece, the cap, the neck, the piston and in the design of the discharge valves for other dentifrice dispensers, especially in connection with the inner parts which are exposed to the enclosed dentifrice and again when required, of course, pullable adhesives can be used. .

In addition, the material delays the loss of taste into drums and when the material is cast as a film on the inner surfaces of fibrous drums which are used for storage of flavored dentifrices. thereby extending the shelf life. Various modifications of the invention have been described herein, and these and other changes may, of course, be made without departing from the scope of the present invention. '

Claims (4)

10 15 20 466 645 ll P a t e n t k r a v A compressible paste dispensing container of bonded material layers, comprising two thermoplastic layers and an inner metal foil layer, the container comprising a first innermost layer (II) of polypropylene, a second second innermost layer (13) of metal foil, characterized in that a third adjoining layers (15) of paper and a fourth outer layer (16) of polypropylene. Container according to claim 1, characterized in that the first layer of polypropylene is connected to the metal foil by means of an adhesive (12). Container according to claim 1 or 2, characterized in that the third layer of paper is connected to the fourth layer of polypropylene by means of an adhesive (14). Container according to one of Claims 2 and 3, characterized in that the binder is a copolymer of ethylene and acrylic acid.