JPS5921775B2 - How to apply surface protection material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for releasably attaching a surface protection material to a processed plate such as a metal plate or a plastic plate.

A surface coated with a pressure-sensitive adhesive on one side of a plastic sheet or film such as polyethylene or polyvinyl chloride as a surface protection material for metal plates such as mirror-finished stainless steel plates and aluminum plates, processed plates such as plastic plates and decorative plates. Protective materials are widely used.

However, the processed plate to which the surface protection material has been temporarily attached is subjected to sheet metal or plastic processing such as drawing, bending, and punching as the next process, but during this processing, unavoidable presence of the plastic sheet or film Processing pressure is concentrated on the fine flat thick parts (harder than other flat parts), and when the thick parts become large, there is often a problem that indentations are created on the surface of the processed plate. It was something that would happen. This problem is more common when the adhesive layer of the surface protection material is thin, or when the surface protection material is a single-layer or two-layer type that has a support function and an adhesive function. The flat thick portion is generally called fin air, and is said to be caused by unmelted portions of the film or sheet, partial crosslinking of molecules due to heat, or the like.

However, the causes of the thick portion include a variety of factors, and the size and shape thereof also vary widely. The pasting method of the present invention provides a maximum diameter O that will form an indentation on the surface of the work plate due to the influence of the thick part even if sheet metal processing is performed after the surface protection material including the thick part is pasted to the work board. 2m7! The present invention provides a removable pasting method that eliminates the flattened thick part of L or more (according to the "Miscellaneous Items Measurement Chart" published by the Printing Bureau of the Ministry of Finance). That is, the present invention provides a pressure-sensitive adhesive layer on one side of a thin base material comprising a flat thick part in the base material, which is made of a thermoplastic plastic film, sheet or tape such as polyethylene, polypropylene, or polyvinyl chloride. A heat-activated thin film, which is provided with an adhesive layer such as a heat-activated adhesive layer, or has a flat thick portion in its base material, such as a film, sheet or tape based on an ethylene monovinyl acetate copolymer. In a method for releasably pasting a surface protection material comprising a single base material having a support function and an adhesive function on a processed plate, the material is heated to a temperature sufficient to melt the base material of the material. affixing the material to the work plate, or heating the work plate after applying the material to the work plate at a temperature sufficient to melt the base of the material, or heating the work plate to a temperature sufficient to melt the base of the material; The material is applied by heating to a sufficient temperature, and then heated to a temperature sufficient to melt the base of the material, temporarily melting the base of the material and removing the base of the material. While the material is in a molten state, a processed plate with a molten surface protection material pasted is processed by passing it between rolls of metal or sandwiching it between a pair of pressure plates made of metal plates. This removable pasting method is characterized in that the flat thick portion is eliminated by applying pressure.

As a method for temporarily melting the base material of the surface protection material, for example, the surface protection material is temporarily melted on the processed plate in advance in a heating furnace maintained at a temperature higher than the melting temperature of the base material of the surface protection material attached to the processed plate. The material is heated to a temperature sufficient to melt the material, and a surface protection material is applied immediately after being fed out, or the processed plate with the surface protection material affixed is inserted into a heating furnace that is maintained at a temperature higher than the melting temperature of the base material of the material. Alternatively, there is a method of using two heating furnaces, one that preheats the processed plate and one that maintains a temperature sufficient to temporarily melt the base material of the surface protection material. By melting, as will be clear from the examples described later, it is possible to obtain a peeling adhesive strength that does not easily peel off even when the surface protection material is processed into a practical sheet metal or plastic material, and it is also easily peeled off after processing. It can be peeled off without deforming metal plates. After temporarily melting the base material of the surface protection material on the surface of the work plate in this way, while the base material of the surface protection material is in a molten state, a cooled metal press roller with mirror finish on one side of the work plate is applied. and a support roller made of hard rubber, with the surface protection material side facing the press roller, and pressurized. Alternatively, one side is sandwiched between a pressure plate made of a mirror-finished metal plate and a pressure support plate. By applying pressure, the flat thick portion is eliminated and the pasted material can be peeled off.

According to the pasting method of the present invention, flat thick parts with a maximum diameter of 0.2 mm or more included in the surface protection material are eliminated, and after the surface protection material is pasted in this way, stainless steel plates, aluminum plates, steel plates, etc. Even when a metal plate is drawn or bent, or a plastic plate is punched, no impressions remain on the surface of the processed plate, such as a metal plate or a plastic plate.

Furthermore, the applied surface protection material has a practical peeling adhesive force and is also characterized in that it can be easily peeled off. The present invention will be explained in more detail below with reference to Examples.

Example 1 A polyethylene resin (manufactured by Mitsui Polychemical Co., Ltd., trade name Mirason 67, Melt Index 22) was extruded into a film with a thickness of 60 μm using an extruder, and a pressure-sensitive adhesive liquid mainly composed of acrylic rubber was applied to the film surface. The thickness after drying is 1
A surface protection material was obtained by applying and drying the coating to a thickness of 0μ.

This material was attached to a BA finish stainless steel plate and deep drawn.

This material has a practical peeling adhesive strength and can be easily peeled off. However, when this material was peeled off, the surface of the stainless steel plate had a maximum diameter of about 0.1 to 0.5 m.
15 indentations of m were observed per M2. Next, the surface protection material was attached to the stainless steel plate in the same way, and then placed in a heating furnace maintained at 200°C for 60 seconds to temporarily melt the polyethylene film, and then taken out to give one side a mirror finish. It was inserted between a cooled metal press roller and a hard rubber roller (load 10k8!/CTn) with the surface protection material side facing the press roller.

Next, when this stainless steel plate was subjected to deep drawing processing in the same manner as above, no peeling was observed at the heat-sealed part, and it had a practical peeling adhesive strength, and could be easily peeled off. When I peeled it off, there were no indentations visible on the surface of the stainless steel plate. Example 2 Ethylene vinyl monoacetate film with a thickness of 50 μm (manufactured by Mitsui Polychemical Co., Ltd., trade name EVAFLEX P-1407, vinyl acetate content 14% by weight, melt index 15)
was attached to a BA finish stainless steel plate.

The film was formed using an extruder. After bending this stainless steel plate, when the film was peeled off, 20 indentations with a maximum diameter of 0.2 to 0.6 mm were found on the surface of the stainless steel plate per M2.

Claims (1)

[Claims] 1 An adhesive layer is provided on one side of a thin thermoplastic base material that includes a flat thick part in the base material, or a single heat-activated thin base material that includes a flat thick part in the base material. In a method for releasably attaching a surface protection material to a processed plate such as a metal plate or a plastic plate, the material is attached to the heated processed plate, or the material is heated after being attached to the processed plate, or the material is heated after being attached to the processed plate. The base material of the material is temporarily melted by heating, and while it is in a molten state, it is inserted between rolls or clamped between pressure plates and pressurized, thereby forming the flat shape. A method for releasably attaching a surface protection material to a processed plate, characterized by eliminating thick parts.