Oriented coextruded film having adhesive multilayer

Abstract

The present invention relates to an oriented coextruded film having an adhesive multilayer with excellent thermal adhesive properties, and more specifically to an oriented coextruded film having an adhesive multilayer capable of direct adhesion with objects to be adhered such as papers, films, metals, and the like. The oriented coextruded film having an adhesive multilayer according to the invention can avoid additional steps such as an EVA lamination coating, uneven thickness, and contamination of rolls during a manufacturing process, and has excellent adhesive force with objects to be adhered.

Description

technical field [0001] The present invention relates to a co-extruded stretched film having multiple adhesive layers excellent in thermal adhesive properties, and more specifically, to a coextruded film having multiple adhesive layers capable of being directly bonded to paper, film, metal, etc. coextruded stretched film. Background technique [0002] In general, as a method of attaching a film to an object to be attached, such as paper, metal, or film, there is a method of coating a biaxially oriented polypropylene film (BOPP) with a primer such as an acrylic or oil-based adhesive ( Primer) and the dry lamination (dry lamination) method that is bonded to the object to be pasted, and the thermal lamination (thermal lamination) method (Republic of Korea registered patent 10-0531256, Republic of Korea registered patent 10-0656264), and the surface layer is combined After extruding a polyolefin resin that can replace the primer layer, ethylene-vinyl acetate resin (EVA) is compo...

AI Technical Summary

Problems solved by technology

However, there are limitations in the production and application of products that simply increase the thickness of a single thermal adhesive layer.

First, the polypropylene of the substrate layer has a melting point above 160°C, and the thermal adhesive layer resin has a melting point of 50-110°C. When the substrate layer and the thermal adhesive layer are co-extruded, the resin with a high melting point is used as Based on the set temperature, the thermal adhesive layer resin exhibits more than moderate fluidity, which results in uneven thickness of the thermal adhesive layer

This kind of uneven thickness is weak when the thickness of the thermal adhesive layer is thin, but when the thickness of the thermal adhesive layer is thick, the degree of unevenness is aggravated. In addition, if the production speed is gradually If the thickness increases, the thickness deviation will increase, and there will be a problem that not only the commercial value of the film will be lost, but also the production efficiency will also decrease.

[0006] In addition, when producing a product in which the thickness of the thermally adhesive layer is increased, insufficient adhesion occurs between the thermally adhesive layer and the polypropylene of the substrate layer, a part of the thermally adhesive layer is detached from the film, and the roll is contaminated, resulting in The production of products is carried out in the direction of restricting the resin used as the thermal adhesive layer

Furthermore, the limitation of the resin of the thermal adhesive layer leads to the inability to exhibit sufficient adhesive force when it is bonded to the object to be pasted, such as paper, which is the final application object, and there are limited applications to products with low adhesive force. The problem

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