High-barrier polyolefin composite film

Abstract

The invention discloses a high-barrier polyolefin composite film, which comprises a printing protection layer, a printing decoration layer, an adhesive layer, a sheet-shaped inorganic silica PVA coating layer and a heat sealing layer which are sequentially arranged. The high-barrier polyolefin composite film well overcomes the technical defects of the existing polyolefin composite film by adoptinga PVA coating technology of a sheet-shaped inorganic silica. The high-barrier polyolefin composite film still has excellent barrier performance under high humidity, can reach 0.5-1.0 CC / M2.24 H onlyby coating 0.6-0.8 micron, has excellent fragrance retention, is obviously superior to VMPET and PVDC coating layers, is environment-friendly, has no organic matter emission in the processing process,so that the film is beneficial to recycling; the high-barrier polyolefin composite film can be widely used for packaging liquid foods, such as refrigerated fresh milk, refrigerated yogurt, edible soybean oil, edible vinegar and the like, the packaging cost is reduced, and meanwhile, the quality guarantee performance is improved.

Description

technical field [0001] The invention relates to the field of packaging materials, in particular to a high-barrier polyolefin composite film. Background technique [0002] Since ordinary polyolefin films only have general water vapor barrier properties and poor oxygen barrier properties, they are not used alone when used in high-barrier packaging requirements, but are layered with other barrier materials to improve barrier properties, such as VMPET, AL, etc., but this leads to the mixing of different substrate materials and cannot be recycled normally. [0003] Coating methods can also be used, such as evaporating inorganic silica, aluminum layer, or coating PVDC, etc., but polyolefin has poor heat resistance and is easily affected by thermal deformation to affect end-use performance. At the same time, polyolefin needs to add slip agent Class to increase the opening slip agent to reduce the coefficient of friction, but these low molecular compounds will volatilize and corrod...

AI Technical Summary

Problems solved by technology

[0002] Since ordinary polyolefin films only have general water vapor barrier properties and poor oxygen barrier properties, they are not used alone when used in high-barrier packaging requirements, but are layered with other barrier materials to improve barrier properties, such as VMPET, AL, etc., but this leads to the mixing of different substrate materials and cannot be recycled normally

[0003] Coating methods can also be used, such as evaporating inorganic silica, aluminum layer, or coating PVDC, etc., but polyolefin has poor heat resistance and is easily affected by thermal deformation to affect end-use performance. At the same time, polyolefin needs to add slip agent Class to increase the opening slip agent to reduce the coefficient of friction, but these low molecular compounds will volatilize during vacuum evaporation and corrode the processing equipment

The coating of PVDC barrier layer requires infrared heating and hot air drying. The equipment has a long drying tunnel, and the coating is relatively thick (2 microns after drying). The required drying temperature is high, and the polyolefin film will be stretched and deformed.

Moreover, PVDC is not environmentally friendly, and it will produce carcinogenic dioxins when it is recycled and incinerated for power generation

[0004] The pure PVA coating film on the market has at least the following defects: it usually has very good oxygen barrier properties under dry conditions, but under high humidity conditions, such as 85% RH, its oxygen barrier properties will plummet, so it is used for When it contains high moisture food, it does not have good barrier properties, and it is not a high barrier packaging in the strict sense.

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