CZ220198A3 - Heat stable layered packaging material and process for preparing thereof - Google Patents

Abstract

Packaging material designed to protect high quality products and delicate surfaces, especially large-scale products, such as a car, is a barrier layer (1) and a barrier layer (1) with a bonded contact layer (2), wherein the barrier layer (1) a simple or laminated film of a stable thermoplastic, in particular polyolefins and / or plasticized polyvinyl chloride; the contact layer (2) is a non-fibrous layer, preferably of a non-woven layer synthetic fibers whose free surface (3) is interrupted by hollows útvaiy / 4 /. This packaging material is manufactured according to the invention that the barrier layer / 1 / unilaterally heats up above softening temperature of the surface, the second surface barrier the layer (1) does not reach its softening temperature, and the softened surface the barrier layer (1) is contacted with the contact layer (2), s preferably preheated to a temperature close to the softened surface terrier layer (1), both layers (1, 2) are mechanically interlocking it is pressed, in particular by rolling, whereupon the laminate is cooled.

Description

Thermally stable laminated packaging material and process for its production

Technical field

The invention relates to a non-shrink packaging material supplied in a continuous form and intended for the manufacture of packaging for large-scale or mobile products with a polished, lacquered or other easily damaged surface, for example automobiles.

BACKGROUND OF THE INVENTION

The protection of products during shipping and transport is still ensured either by the classical way of placing in wooden or steel boxes, containers, kegs with various impact pads - or more recently by means of various plastic packaging. Conventional rigid packaging protects the product relatively well, including its surface, but is laborious and costly, which is a noticeable disadvantage especially for products of small or very large dimensions.

Plastic packaging, now widely distributed, consists of two basic groups: rigid plastic packaging - boxes, planes, blisters, cups, bottles - and soft plastic packaging - bags, bags and various special films. Rigid plastic packaging has its relatively specific use - for small products, drugstore and food goods, etc. Here they can protect the stored object not only from contamination, but to a certain extent from damage, including surface disturbance. Their disadvantage is the aforementioned narrow range of applications.

Soft plastic packaging as well as rigid plastic packaging are greatly expanded mainly due to their manufacturing simplicity and affordability. However, their disadvantage is the very low ability to protect the product from damage, in particular against impact. They are produced either in partially closed form as sacks and bags of various sizes or in flat form as foil. Sacks and bags generally do not adhere sufficiently to the surface of the product, which is a defect in sensitive surface products, and moreover, they are not adapted for very large products. Often, the only starting point here is simply wrapping the foils, which is, however, an unstable, laborious and unreliable solution, despite the aesthetic parameters of such a wrapper. A certain compromise between the two routes is stretch or shrink films. Packaging of this type is relatively reliable and acceptable in appearance and is mainly used for pallets.

A common disadvantage of all soft plastic packaging, including shrink films, is the low ability to protect the product from impact or surface damage. Therefore, in products requiring more careful handling, and especially in products with a more delicate surface, damping layers of a nonwoven or similar soft material are sometimes inserted between the shrink wrap and the product surface. To facilitate handling and insertion of the article, in some cases, the web is adhered to the inner surface of the shrink wrap by adhesive.

Large and non-standard products with a high-quality surface cannot be easily, efficiently and economically protected against damage during shipping and transport. In particular, furniture and automobiles are normally only protected by simply wrapping foils. At best, it is a foil sleeve made to measure by welding or sewing. However, this increases laboriousness and the protective effect against surface damage does not increase too much. Even the molded foil wrap provides virtually only surface protection against contamination. The risk of damage to the surface is further increased with the possibility of movement of the package relative to the product, since the likelihood of scratching of the dust particles increases. The shrinkable packaging that is close to the surface of the product cannot be applied except for large and non-standard products due to their dimensions exceeding the dimensions of the thermal tunnel and because these products usually contain components that cannot be subjected to thermal stress without consequence. tunnel. Another problem of the possible application of shrinkable packaging is related to the requirement that some products (cars) and mobile packaging remain mobile.

Due to all these problems, in some cases the packaging is withdrawn at all and, for example, the protection of cars when transported to the point of sale is solved by preserving their surface against undesirable effects. However, the preservative layer must be removed prior to sale and the ecologically negative consequences cannot be avoided. Therefore, for example, a ban on imports of such canned cars is being prepared in the USA.

SUMMARY OF THE INVENTION

Said disadvantages and drawbacks of the known packaging materials for large and non-standard products with an easily damaged surface largely eliminate the thermally stable laminate packaging material according to the invention and the method for its production. SUMMARY OF THE INVENTION The packaging material comprises a barrier layer and a contact layer attached thereto, the barrier layer having a thickness of 0.04 to 0.3 mm being a single or layered film of thermally stable thermoplastic, in particular based on polyolefins and / or softened The polyvinyl chloride, and the contact layer of 0.15 to 2 mm thickness is a nonwoven fibrous layer, preferably of synthetic fibers, in which the ratio of fiber volume to free space is 1:10 to 1: 1 and whose free surface is interrupted by hollow formations to a depth of 10 to 80% of its total thickness. The packaging material according to the invention is produced by heating the barrier layer unilaterally above the softening temperature of the surface, the second surface of the barrier layer not reaching its softening temperature, and contacting the softened surface of the barrier layer with the contact layer at the latest. preferably preheated to a temperature close to the softened surface temperature of the barrier layer, the two layers are mechanically pressed against each other, in particular by rolling, whereupon the layered formation is cooled.

The advantage of the packaging material according to the invention is, in particular, its damping and protective properties, particularly applicable to goods with a high quality and easily damaged surface. The protective effects of the packaging material according to the invention are several times higher compared to the single-layer wrapper formed by the film itself. The effect given by the porous and damping nature of the contact layer - the web - is further enhanced by a system of cavities which can absorb dust particles and eliminate their abrasive action on the product surface. Since this material can be well matched to the shape and dimensions of a particular product, such as a car, by welding or sewing, it is possible to provide a high level of surface protection for products where heat shrink wrapping is used for various reasons (dimensions, thermal sensitivity not an option. In addition to the heat-shrink wrapping, the packaging material according to the invention is advantageous in terms of its reusability. The durability of re-use is higher than that of custom-made packaging made from mere foil. Thanks to the advantageous production method, which utilizes the thermoplastic nature of the barrier materials used - foils, the packaging material is obtained without the use of adhesive in economically favorable sessions.

The thermally stable (non-shrinkable) layered packaging material according to the invention is therefore characterized by its high protective effect, versatility and favorable price balance, which is further enhanced by the possibility of reuse.

Overview of the drawings

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION The accompanying drawing illustrates a cross-sectional view of a packaging material according to the invention when applying the packaging to a painted surface of a product, such as an automobile.

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DETAILED DESCRIPTION OF THE INVENTION

Example 1

The barrier layer I, consisting of a low density polyethylene (LDPE) film of 0.145 mm thickness, and the contact layer 2 of a non-woven PP-based staple-fiber non-woven fleece, 0.25 mm thick and a 1: 8 fiber to space ratio were preheated to temperature. 135 ° C, then the surface temperature of the foil - barrier layer 1 - was unilaterally shocked by an infrared radiator for 2 sec. and the two layers were pressed against each other by a pair of rollers and cooled. The cavities 4 interrupting the free surface 3 of the contact layer 2 reached a depth of 80% of its thickness.

Packaging made of this material showed very good resistance to mechanical damage and surface damage of packed goods. In laboratory abrasion tests, the damage to the surface of the goods was more than 10 times lower than that of conventional packaging film.

Example 2

The barrier layer 1, where a two-layer film based on low density polyethylene and ethylene vinyl acetate (LDPE / EVAc) with a total thickness of 0.1 mm and a thickness ratio of both 10/1 layers, was applied by the EVAc side to the contact layer of a 2-fleece similar to Example 1 but with a thickness of 0.40 mm and a fiber to space ratio of 1: 3. The layers were heated together to 125 ° C and kept under pressure for 20 sec. Then the pressure was released and the resulting laminate was cooled. The cavities 4 of the contact layer 2 reached a depth of 25% of its thickness. Packaging made of this material has excellent protective effects for smaller goods with a delicate surface.

Claims (6)

Thermally stable laminate packaging material, characterized in that it comprises a barrier layer (1) and a contact layer (2) attached thereto, the barrier layer (1) having a thickness of 0.04 to 0.3 mm being a single or laminated film a thermally stable thermoplastic, in particular based on polyolefins and / or plasticized polyvinyl chloride, and the contact layer (2) having a thickness of 0.15 to 2 mm is a nonwoven fibrous layer, preferably of synthetic fibers, wherein the fiber volume to space ratio is 1:10 to 1: 1 and whose free surface (3) is interrupted by hollow formations (4) to a depth of 10 to 80% of its total thickness. The thermally stable laminate packaging material of claim 1, wherein the barrier layer (1) is a two-layer thermoplastic film having a different softening point, the thermoplastic forming the outer surface of the barrier layer (1) having a higher softening point than the thermoplastic adjacent to it. a contact layer (2). A method for producing a thermally stable laminate packaging material according to claim 1, characterized in that the barrier layer (1) is heated unilaterally above the softening temperature of said surface, wherein the second surface of the barrier layer (1) does not reach its softening temperature, and softened surface. the barrier layer (1) is contacted with the contact layer (2), preferably preheated to a temperature close to the softened surface temperature of the barrier layer (1), at the latest after reaching the softening temperature, both layers being mechanically pressed against each other, especially by rolling; cools. Method for producing a thermally stable laminate packaging material according to claims 1 and 3, characterized in that the barrier layer (1) is heated by total preheating below its softening temperature and by subsequent one-sided shock surface heating above this temperature. 9 9 99 9 44 * 4 4 9 9 99 8 Method for producing a thermally stable laminate packaging material according to claims 1 to 3, characterized in that the barrier layer (1) is heated by an overall temperature increase to a value between the softening temperatures of the two thermoplastics forming the barrier layer (1). Method for producing a thermally stable laminate packaging material according to claims 1 to 3 and according to claim 5, characterized in that the contact layer (2) is contacted with the barrier layer (1) before heating of the layers begins.