JPH05263051A - Surface protecting film - Google Patents

Abstract

PURPOSE:To provide a surface protecting film which comprises a substrate layer made of a thermoplastic resin and a self-adhesive or adhesive layer formed on one side of the substrate layer, undergoes little change in self-adhesiveness with time, and leaves behind little paste to various objects when peeled from them by forming a specific self-adhesive or adhesive layer on the substrate layer. CONSTITUTION:A self-adhesive or adhesive layer comprising a mixture of an acrylic ester (co)polymer (mixture) (e.g. an ethylene-ethyl acrylate copolymer) with a tackifier (e.g. an arom. petroleum resin) is formed on one side of a substrate layer made of a thermoplastic resin (e.g. PE), thus, giving the objective film.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is used to temporarily adhere various synthetic resin plates, decorative plywood, metal plates, etc. to the surface and protect the surface thereof so as to prevent adhesion of dust and scratches. The present invention relates to a surface protection film.

[0002]

2. Description of the Related Art Conventionally, a surface protective film having a pressure-sensitive adhesive layer (adhesive layer) formed on one surface of a base material layer made of a thermoplastic resin such as polyethylene is well known. However, the initial adhesive force (temporary adhesive force) to various synthetic resin plates, decorative plywood, metal plates, etc., changes over time in the adhesive force (temporary adhesive force), adhesive residue on various products, etc. are sufficient for all conditions. There was nothing and improvement was strongly desired. In the production of this surface protection film,
A thermoplastic resin that is a base material layer and a pressure-sensitive adhesive layer or an adhesive layer component are often produced by a coextrusion method, and a pressure-sensitive adhesive layer or an adhesive layer component that is suitable for melt extrusion is required. ing.

[0003]

DISCLOSURE OF THE INVENTION The present invention provides a conventional surface protective film having insufficient initial adhesive strength (temporary adhesive strength), a large change in adhesive strength (temporary adhesive strength) with time, and peeling from various articles. Another object of the present invention is to provide a surface protective film which solves the drawbacks such as the adhesive residue.

[0004]

Means for Solving the Problems The present invention provides a surface protective film having a pressure-sensitive adhesive layer or an adhesive layer formed on one surface of a base material layer made of a thermoplastic resin, wherein the pressure-sensitive adhesive layer or the adhesive layer comprises: The present invention relates to a surface protective film comprising a homopolymer, a copolymer of acrylic acid ester, or a mixture (A) thereof, and a tackifier (B).

The resin used as the base material layer in the present invention is a thermoplastic resin in general and a pressure-sensitive adhesive layer (adhesive layer).
Examples of the homopolymer, copolymer, or mixture (A) of acrylic acid ester used as above include the following.

Acrylic ester monomers include methyl acrylate, ethyl acrylate, butyl acrylate, hexyl acrylate, cyclohexyl acrylate, octyl acrylate, hydroxyethyl acrylate, methoxyethyl acrylate, etc., and other copolymerizable monomers. And styrene, styrene-based monomers such as α-methylstyrene and t-butylstyrene, nitrile monomers such as acrylonitrile and methacrylonitrile, methacrylic acid ester monomers such as methyl methacrylate and butyl methacrylate, ethylene, Examples thereof include olefin monomers such as propylene, 1-butene, isobutylene and 2-butene, vinyl ether monomers such as methyl vinyl ether, ethyl vinyl ether and butyl vinyl ether. In addition, these can also be used as a mixture of 2 or more types.

As the tackifier (B), rosin,
Commonly known tackifiers such as modified rosin, rosin ester, terpene resin, alkylphenol resin, xylene resin, coumarone indene resin, and petroleum resin are used, and the addition amount thereof is generally the resin of (A) above. It is about 1 to 10 parts by weight with respect to 100 parts by weight.

Further, if necessary, other additives such as an ultraviolet ray inhibitor, an antioxidant, a filler, a lubricant and the like can be added within a range that does not impair the basic properties.

[0009]

In the surface protective film of the present invention, since the pressure-sensitive adhesive layer or the adhesive layer is made of an acrylic acid ester homopolymer, copolymer, or a mixture thereof, the conventionally known ethylene-vinyl acetate copolymer is used. Compared with polymers and styrene-butadiene block copolymers, etc., they are superior in thermal stability, have a strong initial adhesive force (temporary adhesive force), little change over time, and no adhesive residue on various articles. Further, this pressure-sensitive adhesive (adhesive) composition has good melt extrusion characteristics and is suitable for coextrusion with a thermoplastic resin.

[0010]

EXAMPLES The present invention will be described with reference to the following examples, but these are merely examples and the present invention is not limited thereto. In the examples, the pressure-sensitive adhesive layer (adhesive layer) <
30 μm thick> and high density polyethylene as the base layer <3
The surface protection film produced by coextrusion was used as 0 μm thickness>. Table 1 shows the composition of the pressure-sensitive adhesive layer (adhesive layer). Table 2 shows the adhesive strength and adhesive residue of this surface protective film initially on a stainless steel plate and a vinyl chloride laminated steel plate and after storage at 50 ° C. for 1 month. However, the adhesion was measured by peeling at 180 ° C.

[0011]

[Table 1]

[0012]

[Table 2]

[0013]

EFFECT OF THE INVENTION The surface protective film according to the present invention has less problematic adhesive strength (temporary adhesive strength) with time, has no adhesive residue on various articles, and has excellent adhesiveness to finely textured products. However, it has an appropriate adhesive strength and is suitable for production by the coextrusion method.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location B32B 27/30 A 8115-4F C09J 133/06 JDB 7921-4J

Claims (1)

[Claims] 1. In a surface protective film having a pressure-sensitive adhesive layer or an adhesive layer formed on one surface of a base material layer made of a thermoplastic resin, the pressure-sensitive adhesive layer or the adhesive layer is a homopolymer of acrylic acid ester. , Copolymers or mixtures thereof (A)
A surface protective film comprising a tackifier (B) and a mixture thereof.