JPS6022623B2 - Vapor deposition sheet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION It is known to bond an aluminum vapor-deposited plastic film and a polystyrene sheet with an adhesive such as EVA, EAA, or urethane to produce a vapor-deposited sheet that can be formed into a sheet.

However, these vapor-deposited sheets undergo changes over time during storage.

That is, there is a problem in that the deposited aluminum causes corrosion. The present inventor has hereby obtained an aluminum vapor-deposited sheet which does not cause the corrosion problem of real aluminum over a long period of time.

That is, a titanium-based, imine-based, butadiene-based, or urethane-based anchoring agent is applied to the aluminum-deposited surface of a plastic film on which aluminum is vapor-deposited, or an olefin such as a molten polyethylene resin or ethylene-propylene copolymer resin is applied. Coat the resin.

Thereafter, the olefin resin-coated surface and the polystyrene sheet were laminated using a general laminating method such as EVA, EAA, or urethane to obtain a vapor-deposited sheet free of aluminum corrosion. The present invention will be explained in more detail below with reference to Examples.

EXAMPLE A 25 mm thick film of unoriented polypropylene was activated by corona treatment to a leakage index of 4 yn/g, and aluminum was vacuum deposited to a thickness of 40 mm.

The above film was set in the feeder of an extrusion lamination machine, a titanium-based anchor agent was applied to the aluminum deposition surface using the AC part of the machine, and the extrusion temperature was immediately increased to 33°C in-line.
A molten polyethylene resin extruded at 0 qo was applied to a thickness of 10 mm.

The line speed was 130 m/min. Furthermore, EVA adhesive resin (vinyl acetate ratio 16%) is applied to the polyethylene coated surface.
(Main component: EVA) was coated.

On the other hand, a polystyrene color compound (trade name, Denka Styrol HI-E-4 type, manufactured by Denki Kagaku Kogyo Co., Ltd.) was melt-extruded at a die temperature of 200 qo to a thickness of 0.38 m/cm.
The sheet is made into a sheet having a diameter of 60 q0 and is guided to a chill roll, where the sheet is cooled to a temperature of 60q0 and sent to a thermocompression roll. The EVA resin surface of the film was thermocompression bonded to the EVA resin surface using a heat shield roll at a roll temperature of 90°C.

A 20/kite tape-shaped test piece was cut out from the obtained composite sheet, and the polystyrene layer and EVA layer of the test piece were cut out.
The adhesive layer was peeled off at 180 qo, and the peeling force was measured using a tensile tester at a peeling rate of 20 m/min, and the peel strength was 300 to 600 momme. Similarly, when the peeling force between the aluminum adhered surface and the polyethylene layer was measured, it showed a strength of 500 mm or more. On the other hand, a bento box was formed by sheet forming with the film surface facing the inner surface. This bento box does not deform even if you immediately put freshly cooked rice into it, nor is it affected by strongly acidic foods.

Moreover, even when placed in a microwave oven, the contents could be heated sufficiently without causing discharge. Also, -20℃ and 160pm
The conventional sheet and the sheet according to the present invention were placed in a heat cycle tester that ran one cycle in 2 hours at 90% R. It was left humidified during the day.

When taken out after 4 days, the conventional sheet had numerous aluminum corrosions of 3 to 5 diameters/skin, but the improved sheet shown in this example had no corrosion at all.

Claims (1)

[Claims] 1. A vapor-deposited sheet obtained by vapor-depositing aluminum on a plastic film capable of aluminum vapor deposition, coating the aluminum-deposited surface with an olefin resin, and then laminating it with a polystyrene-based sheet.