JPH0246626B2 - GOSEIJUSHIITAYOHYOMENHOGOZAI - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a surface protection material for synthetic resin plates. Traditionally, synthetic resin boards have been prone to scratches on their surfaces, and dust and chips from shearing tend to adhere to them during processing, transportation, storage, etc., so various methods have been used to protect the surfaces of synthetic resin boards. Surface protection materials have been proposed and used. For example, kraft paper
There is a protective material that uses a synthetic resin film as a base material and adheres it to a synthetic resin plate using a synthetic resin-based or rubber-based pressure-sensitive adhesive. However, the above-mentioned conventional pressure-sensitive type protective materials are not only expensive, but also have too strong adhesion to synthetic resin plates and tend to deteriorate over time. In addition, in recent years, extrusion molding has been widely adopted as a molding method for producing synthetic resin boards, so the above-mentioned conventional methods have been used for extruded resin boards (methacrylic boards, polycarbonate boards, polyvinyl chloride boards, polystyrene boards). When using a pressure type protective material,
The current situation is that the board temperature causes floating wrinkles, etc., and it does not play its role as a protective material. This is because the temperature of the synthetic resin board on the extrusion molding line ranges from 20°C to 100°C. For example, if a pressure-sensitive surface protection material is applied at 100°C, paper or film may be used as the base material. If the protective material is attached too tightly, it will become floating, and during shearing, chips from the synthetic resin board will get trapped between the floating protective material and the synthetic resin board, causing surface flaws.On the other hand, in areas where the adhesive is too strong, it may become impossible to peel off. However, this is problematic when attempting to print a trademark or the like on the board surface by partially peeling off the surface protection material. Pressure-sensitive type protective materials based on paper or film have a plate temperature limit of up to 60°C, and self-adhesive type film protective materials are difficult to peel off from synthetic resin plates with high plate temperatures, and cannot be used outdoors. Changes occur over time if left unattended. Furthermore, some surface protection materials are made of paper or film as a base material and have a wet-type adhesive layer formed thereon, but conventional products are not suitable for extrusion-molded synthetic resin plates with high plate temperatures on the molding line. It was difficult to use because it could not adapt to board temperature and line speed for consistent adhesion. Therefore, the present invention aims to provide a water-applying type surface protection material that also has the re-adhesive property that is a characteristic of a pressure-sensitive type.
Its composition is as follows (1) on one side of the paper base material.
- (5) A water-dispersed acrylic resin consisting of five components,
It is characterized by forming an adhesive layer composed mainly of a water-soluble resin. (1) Acrylic acid or methacrylic acid alkyl ester having an alkyl group containing 6 to 12 carbon atoms with a monomer content of 20 to 80% (2) Acrylic acid or methacrylic acid having an alkyl group containing 5 or less carbon atoms Alkyl ester with a monomer rate of 20-80% (3) Glycidyl acrylate and glycidyl methacrylate with a monomer rate of 1-20% (4) N-methylolalkylolamide of acrylic acid or methacrylic acid with a monomer rate of 1-20% (5) α - Monomer ratio of olefin carboxylic acid is 2~
15% However, (3) and (4) can be used alone or in an appropriate combination. Furthermore, in order to further stabilize the adhesive layer, the present invention is characterized in that a coating layer made of polyolefin resin is formed on the other surface of the base material in the above structure. Next, to explain the surface protection material of the present invention in detail, in FIG. 1 (FIG. 2) of the attached drawings, 10 is a base material made of paper such as kraft paper, and 20 is formed on one side of the base material 1. The adhesive layer is mainly composed of a water-dispersed acrylic resin (10 to 80% by weight) and a water-soluble resin (10 to 80% by weight), and preferably contains some softening agent (0 to 10% by weight). ) and an antifoaming agent (0.01 to 0.1 weight), add moisture to this adhesive layer 20 with steam or water spray, dissolve the adhesive layer 20, and stick it to the synthetic resin plate P. be done. According to the adhesive layer 20, even after the moisture has been dispersed after use, the adhesive layer 20 has sufficient adhesion that does not cause wrinkles, peeling, etc. even on synthetic resin boards with a high board temperature. It maintains a stable adhesion due to its adhesive properties. In other words, when the adhesiveness disappears, floating wrinkles and peeling are often observed on high-temperature plates.
Furthermore, if the adhesiveness is too strong, the problem of inability to peel occurs, but this phenomenon does not occur with the surface protection material of the present invention. Furthermore, in FIG. 3 (FIG. 4), 30 is a coating layer made of polyolefin resin formed on the other surface of the base material 10 opposite to the adhesive layer 20,
When the coating layer 30 is formed, it has a large effect of suppressing moisture evaporation in the adhesive layer 20 and also has an effect of controlling moisture from the outside air, thereby making the adhesive layer 20 more stable. That is, by forming the coating layer 30, the adhesion state of the adhesive layer 20 to the synthetic resin P as a surface protection material can be more stabilized, and the occurrence of floating wrinkles can be more reliably prevented. Next, regarding the water-dispersed acrylic resin which is the main component of the adhesive layer 20 described above, (1) acrylic acid or methacrylic acid alkyl ester having an alkyl group containing 6 to 12 carbon atoms with a monomer ratio of 20 to 80%; % (2) Acrylic acid or methacrylic acid alkyl esters having an alkyl group containing up to 5 carbon atoms with a monomer content of 20 to 80% (3) Glycidyl acrylate and glycidyl methacrylate with a monomer content of 1 to 20% (4) Acrylic acid or N-methylolalkylolamide of methacrylic acid with a monomer rate of 1 to 20% (5) α-olefincarboxylic acid with a monomer rate of 2 to 20%
15% [However, (3) and (4) may be used alone or in an appropriate combination. ] It consists of the five components (1) to (3) above, which are emulsion polymerized. Therefore, regarding how to combine them, (1)(2)(3)(5), (1)(2)(4)(5), (1)(2)(3
)(Four)
(5). Furthermore, water-soluble resins as main components include (1) cases consisting of water-soluble polymers such as partially saponified polyvinyl acetate, starch, dextrin, gelatin, polyvinylpyrrolidone, and polyethylene oxide, and (2) cases consisting of methylcellulose and hydroxyethylcellulose. , a water-soluble cellulose derivative such as an alkali salt of carboxyethylcellulose. The proportion of the water-dispersible acrylic resin and water-soluble resin as the main components, and the polyvinyl alcohol that maintains rewet adhesive strength must be within a range that maintains tackiness, and details will be discussed later. However, although this may vary depending on the polymerization ratio of the water-dispersed acrylic resin, it is necessary to consider the fact that blending with polyvinyl alcohol reduces tackiness when blending. The formulation of the water-dispersed acrylic resin and water-soluble resin as the main components, and preferably the addition of a softener and an antifoaming agent, is specified in the examples below. Next, the composition of the main component of the water-dispersed acrylic resin is determined in the same manner as in ordinary emulsion polymerization. The initiator and the like are conventionally used and are not limited, and are composed as follows. 2-Ethylhexyl acrylate 43 parts Butyl acrylate 30 parts N-methylol acrylamide 1 part Glycidyl methacrylate 2 parts Acrylic acid 4 parts Potassium persulfate 0.5 parts Water 120 parts [Parts by weight] In addition to the above formulation, a softener and an antifoaming agent are added. Specific examples of manufacturing recipes include: [Weight ratio] Water-dispersed acrylic resin (20-60%) 10-80% Polyvinyl acetate partially saponified aqueous solution (5-60%)
30%) 10-80% Glycerin or polyethylene glycol (number of moles added: 200-20,000) 0-10% Antifoaming agent 0.01-0.1% The blending ratio according to the above formulation is a sticky ratio and is limited to this only. It's not a thing. Furthermore, partially saponified polyvinyl acetate is generally polyvinyl alcohol, and its physical and chemical properties may vary depending on the amount of saponification. In general, type N...completely saponified type A type...semi-completely saponified type G type...partially saponified type K type...partially saponified type Degree of polymerization H...degree of polymerization 1500 or more M...1000-1500 L... 〃 1000 or less The display may vary depending on the manufacturer, but for example
GL-05 is a partially saponified type with a degree of polymerization of 500. Next, when considering moisture permeability as one point, the moisture permeability of the polyolefin resin of the coating layer 30 formed on the other side of the base material is: 60 g/m ² · 24 hr for polyethylene resin, 55 g for polypropylene resin /m ²・24hr However, polyethylene resin and polypropylene resin shall be laminated on cardboard 40g/m ² and 15μ thick kraft paper. The features of the surface protection material according to the present invention described above are (1) It can be bonded to synthetic resin plates (methacrylic plates, polycarbonate plates, vinyl chloride plates, polyethylene plates, etc.) even when the plate temperature is 100°C or higher. . (2) Conventional surface protection materials tend to raise and wrinkle due to plate temperature, so in the case of extruded plates, the application speed is slowed down or the plate is cooled using a cooling (plate temperature cooling) device. In the case of this invention, the speed of the bonding work can be increased without being affected by the plate temperature. (3) Synthetic resin plates are usually heat-formed, and preliminary drying may be required for heat-forming. For polycarbonate plates, it may take several hours at 120 to 130℃, but with conventional products, if the surface protection material was left attached, it would fall off during drying or be impossible to remove after drying, but this invention In the case of , all of these problems are solved and the board surface is reliably protected. (4) In the case of this invention, as mentioned above, there is no floating wrinkles, so even if shearing is performed with the surface protection material attached, there is no risk of chips entering between the surface protection material and the synthetic resin board. . (5) In the case of the present invention, although it is a water-applying type, it has a property that it can be re-attached even if it is partially peeled off for printing or the like after the surface protection material is attached. (6) In the case of the invention in which a polyolefin resin coating layer is formed on the other side of the paper base material, the influence on plate temperature is further reduced, and the protective functionality of the surface protection material is maintained better. Next, examples of the present invention will be described in detail below along with comparative examples. In practice, a polyolefin resin is laminated on one side (rough side) of 40g/ ^m2 one-sided kraft paper, and each adhesive is coated on the base material surface (on the side) to form a surface protection material. After drying, a surface protection material was bonded to the synthetic resin board by spraying water or steam, and the adhesive strength, re-adhesion, weather resistance, adhesive residue on the board surface after peeling, etc. were tested. Example 1 Water-dispersed acrylic resin main component 45g Polyvinyl alcohol GL-05 50g Glycerin 5g SN-Deformer154 0.1g Example 2 Water-dispersed acrylic resin main component 60g Polyvinyl alcohol GL-05 35g Glycerin 5g SN-Deformer 154 0.1g Implementation Example 3 Main component of water-dispersed acrylic resin 55g Methyl cellulose (manufactured by Matsumoto Yushi Co., Ltd., trade name Marborose M-25) 40g Polyethylene glycol #200 (number of moles added 200)
5g SN-Deformer 154 0.1g Example 4 Water-dispersed acrylic resin main component 55g Hydroxypropyl methylcellulose (manufactured by Shin-Etsu Chemical Co., Ltd., trade name Metrorose 65SH50)
40g Polyethylene glycol #200 (number of moles added: 200)
5g SN-Deformer 154 0.1g Comparative example 1 Polyvinyl alcohol GL-05 95g Polyethylene glycol #200 (number of moles added 200)
5g NOPCO 8034 0.1g Comparative Example 2 Polyvinyl Alcohol GL-05 50g Polyvinyl Alcohol GH-17 45g Glycerin 5g NOPCO 8034 0.1g *Resin concentration of methylcellulose and hydropyropylmethylcellulose is 7%. The main component of water-dispersed acrylic resin has a resin concentration of 40%. Polyethylene glycol #200, glycerin
100% concentration. Polyvinyl alcohol GL-05 has a 15% concentration. Polyvinyl alcohol GH-17 has a concentration of 15%. NOPCO8034 (mineral oil) and SN-Deformer 154 (mineral oil) are trade names of San Nobuco Company.

【table】

[Table] The above examples are for a surface protection material (described in claim 6) in which an adhesive layer is formed on one side of the base material and a coating layer made of polyolefin resin is formed on the other side. However, a surface protection material that does not have a coating layer (as described in claim 1)
When the test was carried out under the same conditions, it was found that the adhesion strength, adhesion strength over time, and re-adhesion strength were lower than those in the previous table by a slight difference that had no effect on achieving the purpose of the invention. *Note: ΓAdhesion measurement conditions: Measure after standing for 20 hours under 20℃ x 60%RH conditions. Adhesive force unit g/100mm width Peeling speed 300mm/min Peeling angle 180 pilling Γ Adhesion strength over time Γ Adhesion strength after being left for 90 days under 20℃ x 60% RH conditions Γ Weather resistance Adhesion strength Γ after irradiation for 200 hours with a weatherometer Adhesive Residue 〇…No adhesive residue is observed (no visible glue remains on the synthetic resin board) ×…Adhesive residue is observed (no visible glue remains on the synthetic resin board) − …Adhesion strength cannot be measured in a floating state /…When the synthetic resin board itself is not suitable for the pre-drying conditions of 120℃ x 4 hours before molding processing

[Brief explanation of the drawing]

The figures illustrate embodiments of the present invention, and FIG. 1 is a cross-sectional view, FIG. Figure 4 is a sectional view of the previous figure when in use. 10... Base material, 20... Adhesive layer, 30... Covering layer,
P...Synthetic resin board.

Claims (1)

[Scope of Claims] 1. An adhesive layer composed mainly of a water-dispersed acrylic resin consisting of the following five components (1) to (5) and a water-soluble resin on one side of a paper base material. A surface protection material for synthetic resin boards, characterized by forming the following. (1) Acrylic acid or methacrylic acid alkyl ester having an alkyl group containing 6 to 12 carbon atoms with a monomer content of 20 to 80% (2) Acrylic acid or methacrylic acid having an alkyl group containing 5 or less carbon atoms Alkyl ester with a monomer rate of 20-80% (3) Glycidyl acrylate and glycidyl methacrylate with a monomer rate of 1-20% (4) N-methylolalkylolamide of acrylic acid or methacrylic acid with a monomer rate of 1-20% (5) α - Monomer ratio of olefin carboxylic acid is 2~
15% However, (3) and (4) can be used alone or in an appropriate combination. 2. The surface for a synthetic resin board according to claim 1, wherein a small amount of a softening agent and an antifoaming agent are added to the adhesive layer mainly composed of a water-dispersed acrylic resin and a water-soluble resin. Protective layer. 3. The surface protection material for a synthetic resin board according to claim 1, wherein the water-soluble resin is a water-soluble polymer such as partially saponified polyvinyl acetate, starch, dextrin, gelatin, polyvinylpyrrolidone, or polyethylene oxide. 4. The surface protection material for a synthetic resin board according to claim 1, wherein the water-soluble resin is a water-soluble cellulose derivative such as methylcellulose, hydroxyethylcellulose, or an alkali salt of carboxyethylcellulose. 5. An adhesive layer composed mainly of a water-dispersed acrylic resin consisting of five components (1) to (5) as shown below and a water-soluble resin is formed on one side of a paper base material, and the base material A surface protection material for synthetic resin boards, characterized by forming a coating layer of polyolefin resin on the other side. (1) Acrylic acid or methacrylic acid alkyl ester having an alkyl group containing 6 to 12 carbon atoms with a monomer content of 20 to 80% (2) Acrylic acid or methacrylic acid having an alkyl group containing 5 or less carbon atoms Alkyl ester with a monomer rate of 20-80% (3) Glycidyl acrylate and glycidyl methacrylate with a monomer rate of 1-20% (4) N-methylolalkylolamide of acrylic acid or methacrylic acid with a monomer rate of 1-20% (5) α - Monomer ratio of olefin carboxylic acid is 2~
15% However, (3) and (4) can be used alone or in an appropriate combination. 6. The surface protection material for a synthetic resin board according to claim 5, wherein the polyolefin resin layer is a polyethylene resin layer. 7. The surface protection material for a synthetic resin board according to claim 5, wherein the polyolefin resin layer is a polypropylene resin layer.