JPH0411595B2 - - 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, extrusion molding has recently been widely adopted as a molding method for manufacturing synthetic resin boards, so extruded resin boards (methacrylic boards, polycarbonate boards,
Currently, when the above-mentioned conventional pressure-sensitive type protective material is used for a polyvinyl chloride board, it does not function as a protective material due to the occurrence of wrinkles and the like due to the board temperature. 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 attached at 100°C, paper or film is used as the base material. If the protective material is adhered too tightly, it will become floating and during shearing, chips from the synthetic resin board will enter between the floating protective material and the synthetic resin board, causing surface flaws.On the other hand, if the adhesive is too strong, it may become impossible to remove it. This is problematic when attempting to print a trademark or the like on the board surface by partially peeling off the surface protection material. Conventional pressure-sensitive protective materials based on paper or film have a plate temperature limit of 60°C, and self-adhesive film protective materials are difficult to peel off from synthetic resin plates with high plate temperatures. , changes occur over time when left outdoors. 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 surface protection material for synthetic resin boards that can be used as a water-applying type as well as a pressure-sensitive type. 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 is formed, and a ceramic resin or a modified ceramic is applied to the other side of the base material. Natural resins such as
It is characterized by forming a coating layer of fluorine-based synthetic resin. (1) Acrylic acid or methacrylic acid alkyl esters having an alkyl group containing 6 to 12 carbon atoms with a monomer ratio 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 ratio of 20-80% (3) Glycidyl acrylate and glycidyl methacrylate with a monomer ratio of 1-20% (4) N-methylolalkylolamide of acrylic acid or methacrylic acid with a monomer ratio of 1-20% (5) α -Olefincarboxylic acid with monomer ratio of 2~
15% However, (3) and (4) can be used alone or in an appropriate combination. 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 paper base material such as kraft paper, 2 is a paper base material such as kraft paper, etc.;
0 is an adhesive layer formed on one side of the base material 10, which 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 is preferably is composed of some softening agent (0 to 10% by weight) and antifoaming agent (0.01 to 0.1% by weight). Moisture is added to this adhesive layer 20 by steam or water spray, and the adhesive is Although it is possible to melt the layer 20 and adhere it to the synthetic resin plate P, it is also possible to apply pressure to the adhesive layer 20 without adding moisture to the adhesive layer 20 with steam or water spray, and to adhere it to the synthetic resin plate P as it is by pressure sensing. It is also possible to do so. According to the adhesive layer 20, the adhesion property is imparted even after moisture is diffused after use, and it does not cause floating wrinkles, peeling, etc. even on a synthetic resin board with a high board temperature. Possesses a stable adhesion state due to moderate adhesion. 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. 1 (FIG. 2), 30 is a coating layer formed on the other surface of the base material 10 opposite to the adhesive layer 20 and made of natural resin such as ceramic resin, modified ceramic, or fluorine-based synthetic resin. It's hot,
Since 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 as a surface protection material, the adhesion state of the adhesive layer 20 to the synthetic resin plate P 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 20; 80% (2) Acrylic acid or methacrylic acid alkyl ester with an alkyl group containing up to 5 carbon atoms with a monomer ratio of 20 to 80% (3) Glycidyl acrylate or glycidyl methacrylate with a monomer ratio of 1 to 20% (4) Acrylic N-methylolalkylolamide of acid or methacrylic acid with a monomer ratio of 1 to 20% (5) α-olefincarboxylic acid with a monomer ratio of 2 to 20%
15% [However, (3) and (4) may be used alone or in an appropriate combination] Consists of the five components (1) to (5) above, which are emulsion polymerized. Therefore, regarding the combination, (1)(2)(3)(5), (1)(2)(4)(5), (1)(2)(3
)(Four)
(5). Furthermore, the main component water-soluble resins include (1) those made of water-soluble polymers such as partially saponified polyvinyl acetate, starch, dextrin, gelatin, polyvinylpyrrolidone, and polyethylene oxide; and (2) methylcellulose, hydroxyethylcellulose, It may consist of a water-soluble cellulose derivative such as an alkali salt of carboxyethyl cellulose. The mixing ratio of the water-dispersed acrylic resin and the water-soluble resin as the main components must be within a range that maintains tackiness. This may vary depending on the polymerization ratio, and 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 resin composition of the main component of the water-dispersed acrylic resin will be exemplified. Polymerization is carried out at the monomer ratio described in the previous section, and carried out in the same manner as ordinary emulsion polymerization. The initiator, emulsifier, etc. are as usual and are not limited, but there is no problem as long as the monomer ratio is as described in the previous section, but emulsion polymerization is carried out in the following formulation example. 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 NS-230 (manufactured by NOF) 3.0 parts Water 120 parts [Parts by weight] The above polymerized A softening agent, antifoaming agent, etc. are added to the emulsion, and a specific example of the manufacturing recipe is as follows: [Weight ratio] Water-dispersed acrylic resin (20-60%) 10-80% Polyvinyl acetate Partially saponified aqueous solution (5-30%) 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 ratio that has tackiness. However, it is not limited to this only. 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, N type...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...degree of polymerization 1000-1500 L... …Degree of polymerization is 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, regarding the coating layer 30 formed on the opposite side of the base material 10 from the adhesive layer, (1) a natural material such as ceramic resin or modified shellac (reactive silicone reacted with shellac); (2) In some cases, it is formed from a resin. (2) In some cases, it is formed from a fluorine-based synthetic resin. Among natural resins, when modified shellac (reactive silicone is reacted with shellac) is used as the coating layer, it has advantages such as no curing required and no migration during air drying. In addition, when the coating layer is formed of Ceramic resin, solvent resistance such as insolubility in many organic solvents is improved, there is no need for curing, and weather resistance and oil resistance such as no migration when air-dried are also improved. Fluorine-based resins are soluble in alcoholic solvents, but almost insoluble in many other organic solvents.Also, as with Ceramic resins, there is no need for special curing, and they are easily migrated by air drying. It has weather resistance such as not causing The features of the surface protection material according to the present invention described above are (1) It is possible to bond synthetic resin plates (methacrylic plates, polycarbonate plates, vinyl chloride plates, etc.) even when the plate temperature is 30 to 100°C. (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, it is possible to speed up the adhesion work without being affected by temperature. (3) 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. . (4) In the case of the present invention, after being pasted on a base material, it has a property that it can be re-attached even if it is partially peeled off at a later date for printing or the like. (5) Since a coating layer of natural resin or synthetic resin 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. (6) Furthermore, the formation of the coating layer using natural resin or synthetic resin as described above does not require curing and is easy to process, as it can be done at room temperature. It also has good releasability and improves the physical properties of the base material, such as oil resistance and weather resistance. Examples of the present invention will be described in detail below along with comparative examples for each type of release agent. In practice, a natural resin or synthetic resin is applied to one side (rough side) of 40g/cm ² single-gloss kraft paper, and the base material surface (glossy side) is coated with each adhesive to serve as a surface protection material. After drying, depending on the case, it is possible to apply the surface protective material as it is to the synthetic resin board by pressure-sensing, but in this example, after drying, water or steam spray is applied to the adhesive surface of the synthetic resin board or protective paper. Adding surface protection material to the synthetic resin plate, adhesive strength, re-adhesion strength,
The adhesive strength over time, adhesive residue on the board surface after peeling, etc. were tested. Example 1 (Covering layer treated with Cerac resin) Water-dispersed acrylic resin main component 45g Polyvinyl alcohol GL-05 50g Glycerin 5g SN-Deformer 154 0.1g Example 2 (Covering layer treated with Cerac resin) Water-dispersed acrylic resin Main resin component 60g Polyvinyl alcohol GL-05 35g Glycerin 5g SN-Deformer 154 0.1g Example 3 (The coating layer is treated with fluorine-based resin) Water-dispersed acrylic resin main component 55g Methyl cellulose 40g (Product name manufactured by Matsumoto Yushi Company) Marboros M-25) Polyethylene glycol #200 (number of moles added: 200)
5g SN-Deformer 154 0.1g Comparative example 1 The layer is treated with Cerac resin) Polyvinyl alcohol GL-05 95g Polyethylene glycol #200 (added mole number 200) 5g NOPCO 8034 0.1g Comparative example 2 (The coating layer is treated with fluorine resin) Polyvinyl alcohol GL-05 50g Polyvinyl alcohol GH-17 45g Glycerin 5g NOPCO 8034 0.1g *The resin concentration of methylcellulose is 7%. The main component of water-dispersed acrylic resin has a resin concentration of 40%. Polyethylene glycol #200, glycerin is 100%
concentration. Polyvinyl alcohol GL-05 has a concentration of 15%. Polyvinyl alcohol GH-17 has a concentration of 15%. NOPCO 8034 and SN-Deformer 154 are product names of San Nobuco.

[Table] * Note ○ Adhesive strength measurement conditions Measure after standing for 20 hours under 20℃ x 60%RH conditions. Adhesive strength unit: g/100mm width Peeling speed: 300mm/min Peeling angle: 180° peeling ○ Adhesive strength over time Adhesive strength after being left for 90 days at 20℃ x 60% RH ○ Adhesive strength ○...Adhesive residue is visible No (no visible glue remaining on the synthetic resin board) ×...Adhesive residue is visible (no visible glue remaining on the synthetic resin board)

[Brief explanation of drawings]

The figure illustrates an embodiment of the invention, the first
The figure is a sectional view, and FIG. 2 is a sectional view of the previous figure in use. 10...Base material, 20...Adhesive layer, 30...Coating layer, P...Synthetic resin plate.

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. 1. A surface protection material for a synthetic resin plate, characterized in that a coating layer is formed on the other side of the base material by a natural resin such as ceramic resin or modified ceramic, or a fluorine-based synthetic resin. (1) Acrylic acid or methacrylic acid alkyl esters having an alkyl group containing 6 to 12 carbon atoms with a monomer ratio 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 ratio of 20-80% (3) Glycidyl acrylate and glycidyl methacrylate with a monomer ratio of 1-20% (4) N-methylolalkylolamide of acrylic acid or methacrylic acid with a monomer ratio of 1-20% (5) α -Olefincarboxylic acid with monomer ratio of 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.