FR2537095A1 - PACKAGING MATERIAL CONTAINING PESTICIDE AND PACKAGING IN SUCH MATERIAL - Google Patents

Abstract

THE INVENTION RELATES TO A WRAP MATERIAL SUITABLE FOR EXAMPLE TO BE USED FOR THE PACKAGING AND PACKAGING OF EDIBLE SUBSTANCES WHICH ARE SUBJECT TO INSECT INFESTATION. THE ENCLOSURE MATERIAL INCLUDES AT LEAST TWO LAMINATED LAYERS10, 16 OF SHEET MATERIAL AND, BETWEEN THE LAYERS, A CONTINUOUS PESTICIDE COATING14. A FILM OF A VINYL ETHYLENE ACETATE COPOLYMER FORM A LAYER 10 TURNED TOWARDS THE SUBSTANCE 12 SUBJECT TO INSECT INFESTATION, AND A LAYER OF POLYETHYLENE 16 IS LOCATED ON THE OTHER SIDE OF THE PESTICIDE COATING WHICH IS INCORPORATED IN LAYERS. AN INSECT THAT FINDS THE ENVELOPING MATERIAL WILL COME INTO CONTACT WITH THE PESTICIDE, AND INFECTION BY INSECTS WILL BE AVOIDED.

Description

The present invention relates to a wrapping material and, more

particularly a material

  wrapping suitable for packaging and packaging

amount of edible substances.

  The invention relates in particular to the polymer films used for the manufacture of bags, but is not limited thereto It could for example be applied to paper, or even to cardboard made in two or more layers, from which are made bags or other containers, or which are used for packaging. Polymeric films are frequently used for the manufacture of bags in which substances

  edible, e.g. grains, dehydrated foods

  dratés, rice or cereals, are stored Large

  numbers of filled bags can be stacked in boxes

  trepôts, and it is a well known fact that the content of

  bags is widely susceptible to infestation by in-

  harmful sects Such insects can enter the bags by piercing their walls and it is extremely

  difficult to process bags once they have been taken

  Battery. It has been proposed to coat the bags with a pesticide

  or an insect repellant (hereinafter simple-

  designated by pesticide), but the coating tends to peel off and can also be unhealthy for those who handle the bags We have also proposed to incorporate the pesticide

  in polymer compositions as a constituent of this

  these but an inherent difficulty with this solution

  is that the pesticide tends to accumulate in pockets.

  On the surface of the film, there are thus areas with a relatively high concentration of pesticide and

  areas with substantially no pesticides.

  2. Bag infestation and bag infestation can still occur if an insect punctures an area

  film which contains substantially no pesticides.

  According to the invention, a wrapping material suitable for example for wrapping or wrapping edible substances comprises at least two laminated layers of sheet material and, between the layers,

  a continuous coating of pesticide.

  The term "pesticide" here includes a product

growing insects.

  The pesticide may include any insecticide

  suitable or any other pesticidal compound, or a compound

  sition containing one or more active compounds as pesticides There are a large number of such compounds and compositions For a wrapping material intended to be used with edible substances, it is possible to

  use an insecticide of the class usually de-

  signed under the name of pyrethrins, synthetic type

  or from a natural source Pyrethrines can-

  can be used either alone or in combination with a compound with appropriate synergistic activity, such as

  piperonylbutoxide or sesamex, suitable for delaying

  der the metabolic detoxification of the insecticide Natural pyrethrum used alone or in combination with a compound with appropriate synergistic activity, such as piperonyl butoxide, is preferable, since it is considered to have practically no toxic side effects on mammals, and insects don't show

  tendency to develop a defense against it.

  In the present description, the term "pyrethrum

  natural "is used to denote an insecticide obtained from flowers of plants of the genus pyrethrum, for example Pyrethrum cineraefolium and having compounds

  insecticides usually known as pyrè-

  thrines and cinerins as the main insect constituents

active ticides.

  3. Any other suitable pesticide can be used

  depending on the intended application of the wrapping material.

  Synthetic pyrethrins can be used at the

  place of a natural pyrethrum from a natural source

  Preferably, the pesticide is used in a con-

  centration which is practically non-toxic to people

mes and other mammals.

  The two layers of sheet material can

  be linked together in any appropriate way, for example-

ple by means of a binder.

  Any suitable binder compatible with pesti-

  cide can be used When: a pyrethrin is used,

  a non-alkaline binder should be used.

  The binder may include a synthetic resin

and a hardener for it.

  Preferably, the binder comprises a poly-

  urethane, such as that manufactured by Henkel Gmb H and marketed under the brand name of "Liofol UK 2600", and a hardener comprising a crosslinking component such as the product also manufactured by Henkel Gmb H and

  marketed under the brand name of "Liofol UK 5000".

  In a preferred embodiment of wrapping material according to the present invention, the pesticide is incorporated into the binder used to bond the layers

sheet material.

  The pesticide and the binder components can be dispersed in a solvent for application to the layers of sheet material In a coating consisting of the preferred pesticide and a

  binder composition indicated above, the solvent

  preferably takes ethyl acetate.

  Instead of incorporating the pesticide into a

  1 i a N t connecting the two layers of sheet material

  the, the pesticide can be applied either to a layer of the

  sheet material, or both, of any other material

  appropriately, such as by spraying or printing the pesticide coating by any process

  suitable together with the binder or separately.

4.

  In a preferred embodiment of the invention,

  vention, at least one of the two layers of sheet material between which the pesticide is spread, and

  preferably both include a polymeric material.

  Any suitable polymeric material can be used, such as

  than an ethylene-vinyl acetate copolymer and / or a poly-

  polyolefinic mother such as polyethylene or poly-

  propylene. It will be understood that the invention is not limited to packaging and polymeric packaging materials, since paper or cardboard, or composite layers, for example of paper or of a polymeric material, can be brought together by means of a suitable binder, a suitable pesticide being disposed between the layers. The layers of sheet material may comprise any other suitable material. The wrapping material of the invention can be used in the form of a sheet for packaging or for the manufacture of bags, boxes, containers or any

  other packaging desired, depending on its size and flexibility

  se. Packaging, such as product bags

  grain, consisting of sheets of wrapping material

  according to the invention provide resistance to

  insect penetration much better than packaging

  beams made of untreated materials.

  The wrapping material according to the invention can also be used in the form of a sheet for

  line or line interior surfaces with compartments

  storage, silos and similar packaging.

  The wrapping material according to the invention can be used in any other suitable way for

  provide suitable packaging or wrapping,

  for protection against infestation or penetration by harmful insects Thus, a sheet of wrapping material can be placed under and / or on and / or

  around the material or items to be stacked or stored.

  5. A sheet of the wrapping material can constitute a chemical barrier which is resistant to

  penetration by harmful insects Harmful insects

  If digging the wrapping material will come into contact and be subject to the toxic effect of the pesticide. If desired, at least one of the two laminated layers of sheet material between which the pesticide is located may be permeable to the pesticide, so that the latter can migrate to at least one side of the wrapping material, or to other layers from which the wrapping material

is realised.

  Both layers of the sheet material may be permeable to the pesticide, so that the pesticide can

  migrate to both sides of the wrapping material.

  The applicant considers that the migration of the pesti-

  cide for example inside a bag made of 'ma-

  material according to the invention can be advantageous in that harmful insects in the bag can be killed and / or eggs deposited in the bag can be prevented

  to hatch, and / or any creature that hatches can be killed.

  The layer of sheet material arranged for

  be located indoors relative to the pesticide vis-

  against the material intended to be wrapped or packaged

  in the wrapping material may include a copo-

  ethylene vinyl acetate lymer, and may be relative-

  more permeable than the layer or layers of sheet material arranged to be located towards the outside,

  the other side compared to the pesticide.

  The outer layer of the sheet material for-

  ra be formed by co-extrusion of a combined film compre-

  internal and external films of poly-

  relatively low density ethylene taking up sand-

  wich an intermediate polyethylene film

  high density The outer film can

  take an ultra-ray inhibitor or absorbent

  purple, for the reason explained below -

6.

  In the case of pyrethrum, the degradation of the weight

  suicide is likely to take place under the action of

  ultraviolet rays penetrating into the or layers

  packaging material in the event that

  these include polymeric films so in such

  In this case, an ultra-light absorbent should be incorporated.

  any suitable tra-violets available in the com-

  merce in the polymer film, at least for the or the

  outer layers of the laminate wrapping material.

  The invention is described below, by way of

  example only, with reference to a form of realization

  preferred tion given below as an example and in the accompanying drawing, which is a partial cross-sectional view

  and exploded of a wrapping material according to the invention.

  As shown in the drawing, a material of

  velopement according to the invention suitable for example for the production of a bag comprises an inner layer

  of a polymer film consisting of an ethylene copolymer-

  vinyl acetate having a vinyl acetate content

  3%, the inner layer being arranged to be rotated

  born towards an edible substance 12 to keep in the bag The inner layer has a density of 0.930 and a melt index of 1.5 g / m / m as measured according to the

  ASTMD 1238 standard The average thickness of the inner layer

  is 25 microns and its average oxygen permeability rate is 10,000 cm 3 as measured by the

ASTMD 1434-63 (DIN 53 380) standard.

  A continuous coating 14 comprising a binder

  including a pesticide is placed between the inner layer

  10 and an outer layer of sheet material generally designated by the reference number 16, so

  to combine the inner and outer layers 10 and 16.

  The composition of the binder and the pesticide of the coating 14 will be described in more detail with reference to the example and

to the tables below.

  The outer layer 16 is a co-extruded combined polymer film and consists of an inner film 18 of low density polyethylene having a thickness 7. of approximately 7.5 microns, an intermediate film 20 of high density polyethylene having a thickness of approximately 25 microns and an outer film 22 of low density polyethylene having a thickness of about 7.5 microns, the outer film 22 comprising in its composition 0.3% of any suitable commercially available ultraviolet ray inhibitor, which can have the form of an absorbent The average thickness of the outer layer 16 is thus 40 microns and this layer has an average oxygen permeability rate of 2000 cm 3 such

  than measured according to ASTMD 1434-63 (DIN 53 380).

  The wrapping material shown in the drawing has an average combined thickness of the polymer film of 65 microns (without the thickness of the coating 14) and will have an effective storage life of two months. However, it will be noted that the materials used to make the wrapping material may be modified according to

customer requirements.

  For example, a mixture of a binder and a pesticide intended to be placed between the respective inner and outer layers 10 and 16 of the material

  laminate wrapping was prepared by mixing

  time, in liquid form, of a polyurethane resin

  with "Liofol UK 2600", a solvent made up of

  ethyl tate, and a pesticide comprising natural pyrethrum in combination with piperonyl butoxide The constituents of the pesticide were evenly distributed in the mixture A hardener consisting of "Liofol UK 5000" was added, in liquid form, to the mixture above immediately before placing the binder between the inner and outer layers 10 and 16 of the laminated wrapping material The mass of each constituent

  of the binder is indicated in Table I below.

TABLE I

  Constituent Weight (kg) "Liofol UK 2600" 9.00 Ethyl acetate 10.26 "Liofol UK 5000" 0.90 Natural pyrethrum 0.888 Piperonyl butoxide 4.44

25,488

  The mixture was applied between coats

  inner and outer 10, 16 of the envelope material-

  laminate, at a volume of about 8 grams per m of the surface of the layers The mixture was applied continuously and evenly between layers 10 and 16 using a laminating process commonly known as sandwich printing to obtain a continuous and regular coating 14 between the inner and outer layers 10, 16 After the lamination, the material was left to dry A continuous and evenly distributed coating of pesticide was obtained between the inner and outer layers 10, 16 of material sheet Of the 8 grams of binder provided per m 2 of the surface of the layers, it turned out that an average of 0.312 grams of natural pyrethrum and 3.0 grams of

  piperonyl butoxide remained active.

  After drying, the dry content of the constituents of the binder was found to be that indicated in the table

II below.

TABLE II

  Constituent Weight (kg) "Liofol UK 2600" 5.40 Ethyl acetate 0.01 "Liofol UK 5000" 0.675 Natural pyrethrum 0.444 Piperonyl butoxide 4.440, 969 The sheet of laminated wrapping material as described above was then used for

  make storage bags for substances coming-

  targets, which were compared with untreated reference bags made of an available polymer film

in trade.

  Wheat and maize weevils were deposited in a test inside bags containing corn formed from the material according to the invention, and in another test on the outer surface of bags containing corn but similarly formed from a material according to the invention The weevils exposed outside were trapped with the bag in; a Petri dish All the weevils in the above tests were found dead after 24 hours The weevils deposited in the bags reference containing mals were all alive after 7 days while all the weevils trapped in a petri dish outside the bags were found

dead after 7 days.

  Ephestia larvae were also exposed inside the bags formed from the wrapping material according to the invention, and all were found dead after 6 days In the reference bags,

  all larvae were alive after 14 days.

  20 ephestia larvae were also trapped in a petri dish outside the formed bags

  from the wrapping material of the invention during

  during a period of 14 days Out of the 20 larvae, only 4 were found to be alive after this period, and these larvae were found in the petri dish and without contact with the bag All the larvae exposed to the bags

  were alive after the same period.

  It also turned out that no larva hatched eggs of ephestia exposed for 7 days to the bags formed from the film of the invention and used for storing corn flour. A certain number of eggs located in the reference bags were hatched

after this period.

  Note that it is desirable that the

  pesticide incorporated into the enveloping material of the invention

  tion has a concentration and / or type which are safe for the particular application of the material both when the laminated layers of sheet material are

  intact and also when they are perforated

  The pesticide must be non-toxic to humans and other large mammals. The pesticide used to make the wrapping material must comply with the standards established by the relevant health authorities in the territories in which the

bags will be used.

  Although the invention has been described and illustrated with reference to a present preferred embodiment, it will appear to those skilled in the art that many variants and / or modifications are possible without departing

  the scope of the claims which follow For example,

  although the invention has been described and illustrated with reference to

  In the case of a laminated wrapping material having a storage life of two months, the constituents can be modified in an appropriate manner, for example to increase the service life If, for example, the intermediate film 20 of the outer layer 16 has a average thickness of 50 microns instead of the 25 microns proposed in the example, the bags formed of the wrapping material of

  the invention will have a lifespan of about six months.

  Elements such as the thickness and nature of the layers of sheet material, the nature and concentration of the pesticide, how to apply the pesticide, and other characteristics may vary

  to meet special requirements.

  The essence of the invention resides in the fact of providing a laminated wrapping material which can, for example, be used for packaging or packaging.

  edible substances or for the production of packaging

  which is resistant to penetration by insects thanks to the incorporation of a pesticidal material

between the layers of the material.

  1.1 The invention also includes within its scope a package comprising a wrapping material

according to the present invention.

  The packaging may include a coating

  taking a wrapping material according to the invention. As a variant, the packaging can be carried out at least

  partly from a wrapping material according to.

the invention.

Claims (17)

  1 wrapping material, characterized in that it comprises at least two laminated layers (10, 16) of sheet material and a continuous coating of a pesticide (14) between the layers (10, 16) of sheet material .   2 Material according to claim 1, charac-   terized in that the layers (10, 16) of foil material   the are united by means of a binder compatible with the pesticide.   3 Material according to claim 2, character-   laughed in that the binder comprises a synthetic resin   and a hardener for this resin.   4 Material according to claim 2 or claim 3, characterized in that the pesticide is incorporated in the binder.   Material according to one of the claims   previous, characterized in that the pesticide is derived from a natural source.   6 Material according to any one of the res-   dications 1 to 5 characterized in that the pesticide comprises   a pyrethrin as an active ingredient.   7 Material according to claim 6, character-   laughed in that the pesticide includes natural pyrethrum.   -8 Material according to claim 7, character-   laughed in that the pesticide includes pyrethrum in combination   naison with a compound with synergistic activity.   9 Material according to claim 7, character-   laughed at in that the pesticide includes a combination of   natural pyrethrum and piperonyl butoxide.   10 Material according to one of claims   previous, characterized in that at least one of the   Each sheet material (10, 16) is permeable to the pesticide.   11 Material according to one of claims   1 to 10, characterized in that the two layers (10, 16)   sheet material are permeable to the pesticide.   12 Material according to one of claims   previous, characterized in that at least one of   layers (10, 16) of sheet material comprises a material polymer line.   13 Material according to claim 12, charac-   terized in that at least one of the layers (10, 16) of   sheet material includes an ethylene-acetate copolymer vinyl.   14 Material according to claim 12, charac-   terized in that at least one of the layers of material   sheet includes a polyolefin polymer.   Material according to claim 14, charac-   terized in that the polyolefin polymer comprises polyethylene.   16 Material according to claim 12, charac-   terized in that a layer (10) of sheet material comprises an ethylene-vinyl acetate copolymer and that   the other layer (16) comprises a combined polymer film   extruded comprising inner and outer films (18, 22) of low density polyethylene and a film   intermediate (20) of a high density polyethylene.   17 Material according to claims 11 and   16, characterized in that the layer (10) of ethylene-vinyl acetate copolymer is more permeable to the pesticide   than the polyethylene layer (16).   18 Packaging characterized in that it comprises   a wrapping material according to one of claims previous.   19 Packaging according to claim 18, charac-   terized in that it comprises a coating comprising a wrapping material according to any one of claims 1 to 17.   Packaging according to claim 19 made   at least partly dried from a material according to one   any of claims 1 to 17.