FR2557503A1 - SUBSTRATE CONTAINING LAMINATED POLYESTER AND FOLDABLE DISPENSER CONTAINER MADE FROM SUCH SUBSTRATE - Google Patents

Abstract

THE INVENTION RELATES TO A SUBSTRATE FORMED OF LAYERS OF MATERIALS WHICH INCLUDES POLYESTER LAYERS 11, 16 BETWEEN A METAL SHEET LAYER 13 AND A PAPER LAYER 15, WHICH ADHERENTALLY ADHERENTLY TO THE OTHER. THE INVENTION FINDS APPLICATION IN THE MANUFACTURE OF A TOOTHPASTE.

Description

The present invention relates generally

  container technique, and it relates in part; cu-

  bind to a deformable dispensing container having a structure

  ture with a laminated wall at the level of its body part, so that the permeation and absorption of the products as well as the absorption of oxygen are substantially prevented in all regions of the container structure which are susceptible thereof. Deformable tubes formed from metallic or plastic materials have been known for a long time in the field of product packaging. Extruded metal tubes are inherently brittle, and repeated use often causes cracks in the wall so that the product escapes through a point other than the essentially rigid dispensing orifice. Among the metal tubes of the prior art, the

  aluminum tubes, although probably the least cas-

  are sometimes limited in their applications because, up to

  that at present it has not been possible to apply to their sur-

  inside surfaces a completely satisfactory coating when

  that it is necessary to avoid attack and corrosion of the

  metal by alkaline or acidic substances and contamination

  * content nation by reaction products. Without holding

  account for the relatively brittle nature of a metal tube.

  that the mentioned interior coating operation requires

  an additional stage of treatment which increases obligatorily

the price of the final item.

  Tubes made of polyethylene and other plastics have met with great commercial success in the

  packaging of many products; however, we have noticed

  that after a certain period of time, certain other products deteriorate when they were contained in such

  materials. Plastics, for example polyethylene

  are permeable to some extent when used in the walls of tubular containers and

  essential oils incorporated in most dentifri-

  these for flavoring purposes see their volume-decrease during

  during storage of the container, which makes the toothpaste less palatable. Likewise, the wall of the plastic container absorbs oxygen over a period of time and can ultimately decompose the product, which has proven to be the case with toothpaste.

fluoride.

  It has therefore been proposed to have a metal barrier

  relatively thin layer between the product and the body of the polyethylene tube in order to prevent the mentioned loss of oils

  essential as well as oxygen absorption. It was suggested-

  re that the metal barrier is in the form of an intermediate layer between the polyethylene sheets and that a laminate is formed thermally with or without suitable adhesives. However, although a structure of this general character is effective in preventing some permeation to the products and absorption of oxygen by the body of the tube, and in particular when the inner thermoplastic layer

  is a copolymer of an olefin and a polar group containing

  as a copolymerizable monomer, there remains a risk of

  deterioration of the product, although to a much lesser degree.

  A disadvantage presented by a polyole-

  fine lies in the inability of the surface to receive easily-

  printing or decorative material. In addition, the polyo-

  Lefin has a memory effect, that is to say that it does not remain in the deformed state when it is pressed, which;

  is a particular drawback of toothpaste tubes.

  To overcome this lack of deformability, the metal layer must be relatively thick so that its

  deformability is imposed on the plastic.

  Therefore, an important goal of the present in-

  vention is to provide a deformable dispensing container having a laminated wall structure at its part

of body.

  Another object of the present invention is to provide

  to provide a tubular container with several adherent layers

  rents in its body part, one of said layers, for example a metal sheet, forming a barrier to product migration and absorption of oxygen, and another of said layers being made of a polyalkylene material chosen from polyterephthalate ethylene and polybutylene terephthalate or a copolymer thereof with a minor amount of another dicarboxylic acid, modifying the density, the melting point and the crystallinity, the latter layer being the most internal and preferably the more external by

  compared to other different layers included between them.

  These other layers include paper and agents

  suitable bonding adhesives such as an ethylene copolymer

lene and acrylic acid.

  The deformable dispensing container of the present invention can be made from the laminate substrate of the present invention using conventional and known apparatuses. An example of apparatus and process of this type

  is found in the U.S. Patent N 3,832,964.

  Another object of the present invention is to provide a method of producing laminate tubes, wherein a tubular body is formed of a barrier layer and a polyester applied thereon to form a laminate; the body

  laminated tube is then placed on a formative element

  tion in the vicinity of a barrier element which is equal to it

placed.

  Other objects and advantages of the invention emerge

  from the description which follows.

  In the drawings, in which reference numbers

  Identical references are used to designate identical parts.

ticks: -

  - Fig. 1 is a partial cross section of a part

  tie of a laminate substrate of the present invention; - Fig. 2 is a side elevation of a deformable dispensing container in accordance with the new principles of the present invention, portions of the walls of the body being

  torn off to better illustrate the layered structure.

  Referring now firstly to FIG. 1 of the drawings, a substrate 10 is shown in section so

  highlight the components of the sandwich that will

titrate the layered structure.

  The lower layer ll is a polyester. The second-

  layer 12, placed above, is an adhesive layer which joins layer ll of polyester to a third layer 13

  which is a metallic sheet such as an aluminum foil

  nium. A fourth layer 14 constitutes another adhesive which fixes the other surface of the metal foil layer 13 to a paper layer 15. An upper layer 16 is made of polyester. The thermoplastic polyester of the present invention

  includes a polyalkylene terephthalate such as polytere-

  ethylene phthalate and polybutylene terephthalate.

  Applicable polyester resins are described in

  About the Use of Containers in U.S. Patents

  N 3,152,515 and N 4,197,326. These patents describe, for example,

  ple, polyethylene terephthalate as polyester. These-

  vets are cited here for reference.

  The invention contemplates that the adhesives may consist of

  ter into a copolymer of ethylene and acrylic acid or acid

  methacrylic acid, or its sodium or zinc salts, in

a diluent system.

  The metal foil can preferably be a

aluminum foil.

  The paper layer advantageously consists of

Kraft paper.

  The thickness range of each of the layers is as follows: Layer ll of polyethylene terephthalate: 12.7 to

  76.2 micrometers, preferably 25.4 micrometers.

  Adhesive layer 12: sufficient to ensure adhesion

rence.

  Metallic foil layer 13: 12.7 to 50.8 micro-

  meters, preferably 25.4 micrometers.

  Adhesive layer 14: sufficient to ensure adhesion

  rence, Layer of paper 15 - 38.1 to 63.5 micrometers, of

preferably 50.8 micrometers.

  Layer 16 of polyethylene terephthalate: 88.9 to 127 micrometers, preferably 101.6 micrometers.

  The upper layer 16 of polyethylene terephthalate

  does not adhere to the paper layer 15 by applying sufficient heat and pressure to the substrate. In case the application of heat and pressure is not appropriate,

  a suitable adhesive must be used.

  Figure 2 is an example of the layered structure of a deformable container, the layers being arranged as in Figure 1, the layer 11 being the innermost and the other layers being of the same materials and in the same

order as shown.

  It is assumed that it is obvious from the above,

  that the Applicant proposes a deformed container structure

  mable which significantly reduces the difficulties remained until

  present without solution in the prior art. The stra-

  and the laminated shoulder 20 completely eliminates product permeation and oxygen absorption, and this

  very advantageous result is obtained by using materials

  inexpensive res which are preferably combined in the form

  laminated as shown in Figure 2.

  The outer layer of polyethylene terephthalate is a thermoplastic material capable of melting during

  the lateral welding step and to provide a cor-

  recte of paper and metallic foil forming a cover

  che interlayer. The art of sou-dur of a deformable toothpaste tube of the general type described here can be found in the U.S. Patent. N 3,295,725 which is cited here by way of preference. However, the outer layer of polyalkylene terephthalate and that of paper can be removed if the metal foil barrier is thick enough to resist damage, and by pouring a thermoplastic material into the overlapped side seal for

  its sealing when using such a system.

  In addition, the outer layer may be paper, which gives a form of three-layer laminate: paper, sheet and poly (alkyl terephthalate), as described. Because the outermost and innermost layers are preferably the same, the folded edges of the tube produced from the substrate are conveniently bonded to heat. A

  suitable adhesive can be used when the thermal bond

  mique is not possible. This variant is added to the stra-

  tified with four aforementioned layers consisting, from the outside

  inward laughing, polyalkylene terephthalate,

  paper, metallic foil and polyalkylene terephthalate

  lene; or polyalkylene terephthalate, metal foil,

  than paper and polyethylene terephthalate. He is in-

  visaged to use suitable adhesives between coats when necessary. We can use structures

  identical for the shoulder, the cover, the neck, the

  ge, the piston and in the realization of distribution valves

  tion for such containers, particularly in conjunction with the interior portions exposed to the contained toothpaste

  and, again, when necessary, we use

  actually compatible adhesives.

  Various variants of the invention have been described

  and these and other modifications may

  actually be carried out without departing from the scope of the invention.

  In addition, when cast as a film

  on the interior surfaces of the fiber drums used.

  for the storage of flavored toothpaste, the material delays the loss of aroma in the drums, which prolongs the

possible duration of storage.

  Polyethylene terephthalate (PET) is special-

  ment useful because it has very low flavor absorption characteristics, as can be seen from the following tables o PET is compared with polyethylene

  the thicknesses of the layers or coating being the same.

TABLE I

  ABSORPTION OF THE FLAVOR OF A TOOTHPASTE

  (Aging conditions: 1 week at room temperature). Absorbed flavor (Z)

PET 0.1

  Aluminated PET (lI - 2 ohms) 0.0 Aluminated PET (2 - 3 ohms) 0.0 Nylon 6.6 0.5 Polyethylene 2.4

TABLE II

  ABSORPTION OF THE FLAVOR OF A TOOTHPASTE GEL

  (Aging conditions: 2 weeks at temperature

ambient).

Aroma absorbed (%)

PET 0.0

  Aluminized PET (1I - 2 ohms) 0.0 Aluminated PET (2 - 3 ohms) 0.0 Nylon 6.6 0.2 Polyethylene 1.0

R E V E N DI CA T I 0 N S

  1 - Substrate formed of layers of materials, characterized in that it comprises a first layer (11) formed of a

  polyester, a second layer (13) formed of a metal sheet-

  lique, a third layer (15) formed of paper and a qua-

  third layer (16) formed of a polyester.

  2 - Substrate according to claim 1, characterized in

  what polyester is a polymer or copolymer of a poly-

alkylene terephthalate.

  3 - Substrate according to claim 2, characterized in that the polyalkylene terephthalate is a polyethylene terephthalate. 4 Substrate according to claim 3, characterized

  in that the first layer (11) of polyethylene terephthalate

  lene is fixed to the metal sheet (13) using a

adhesive (12).

  - Substrate according to claim 4, characterized in that the third layer (15) formed of paper is fixed

  to the fourth layer (16) formed of polyethylene terephthalate

do with an adhesive.

  6 - Substrate according to claim 5, characterized in that the first layer (11) formed of polyethylene terephthalate is fixed to the metal sheet (13) using

  of an adhesive (12) and the third layer (15) formed by

  pier is attached to the fourth layer (16) formed of poly-

  ethylene terephthalate using an adhesive.

  7 - Substrate according to claim 6, characterized in that the adhesive is a copolymer of ethylene and acrylic acid. 8 - Deformable container for distributing dough formed from layers of materials, characterized in that it comprises a first inner layer (11) formed of a polyester, a second layer (13) formed of a metal sheet, a

  third layer (15) formed of paper and a fourth layer

  che (16) outer formed of a polyester.

  9 - container according to claim 8, characterized

  in that the polyester is a poly (alkylene terephthalate).

  - Container according to claim 9, characterized

  in that the polyester is a polyethylene terephthalate.

  ll - container according to claim 10, characterized in that the first layer (11) formed of polyester is

  attached to the metal foil (13) using an adhesive (12).

  12 - container according to claim 10, characterized

  in that the third layer (15) formed of paper is thin

  attached to the fourth layer (16) formed of polyester using

an adhesive.

  13 - Container according to claim 10, characterized in that the first layer (11) formed of polyester is fixed to the metal sheet (13) using an adhesive (12) and the third layer (15) formed of paper is attached to the

  fourth layer (16) formed of polyester using an adhesive

  sif. 14 - A container according to claim 13, characterized in that the adhesive is a copolymer of ethylene and acid

acrylic.