JP2008115361A - Anti-fogging surface-treating agent and anti-fogging resin sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an anti-fogging treating agent having excellent anti-fogging properties, and to provide an anti-fogging resin sheet. <P>SOLUTION: The anti-fogging surface-treating agent is constituted of (A) a fatty acid amide (with the proviso that a poly(oxyethylene) fatty acid amide is excluded) and (B) a hydrophilic polymer (with the proviso that a polyoxyethylene-polyoxypropylene block copolymer is excluded). The fatty acid amide (A) can be an amide of an 8-30C fatty acid with amines. The hydrophilic polymer (B) can be a polyoxyethylene, a vinylpyrrolidone-based polymer, a vinyl alcohol-based polymer, a cellulose ether, alginic acid or a salt thereof. The ratio (by weight) (A/B) of the fatty acid amide (A) to the hydrophilic polymer (B) can be about (1/99) to (80/20). The anti-fogging resin sheet can be obtained by forming an anti-fogging layer constituted of the surface-treating agent at least on one surface of a resin sheet. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an antifogging surface treatment agent (antifogging treatment agent) useful for imparting antifogging properties to the surface of a resin sheet or the like, an antifogging resin sheet, and a method for producing an antifogging resin sheet. And an anti-fogging container.

  Hydrophobic synthetic resin sheets such as styrene resin sheets are used for packaging containers such as foods, but have low antifogging properties. Therefore, when food or the like is stored in a container formed of the sheet, water vapor adheres to the surface of the container as a minute water droplet due to changes in temperature and humidity, resulting in cloudiness and lowering transparency. For this reason, the visibility of the contents is lowered.

  Then, the method of providing antifogging property to a resin sheet using fatty acid esters etc. is proposed. For example, in Japanese Patent Publication No. 63-62538 (Patent Document 1), an aqueous solution containing sucrose fatty acid ester, unmodified polyvinyl alcohol having a polymerization degree of 800 or less, and a silicone emulsion in a specific ratio is applied to a styrene resin film. A method is disclosed. In JP-A-10-309785 (Patent Document 2), one surface is coated with a mixture of sucrose fatty acid ester and methylcellulose, and this coating layer is further coated with silicone oil, and the other surface is coated with silicone oil. A styrenic resin sheet coated with is disclosed. In Japanese Patent No. 3241497 (Patent Document 3), a surface treatment agent containing a sucrose fatty acid ester, a silicone emulsion, a polysaccharide and / or a hydrophilic polymer (excluding polyvinyl alcohol) is used. Application to at least one surface is disclosed. JP-A-2003-201355 (Patent Document 4) describes a mixture of a polyhydric alcohol type nonionic surfactant such as sucrose fatty acid ester and polyglycerin fatty acid ester and a polyethylene glycol type nonionic surfactant. An antifogging resin sheet whose surface is coated is disclosed. JP-A-2004-238614 (Patent Document 5) discloses a polyhydric alcohol fatty acid ester, a non-ether hydrophilic polymer excluding polyvinyl alcohol, and an ether-based hydrophilic polymer having at least an oxyethylene unit. An anti-fogging sheet coated with a surface treatment agent composed of silicone oil is disclosed.

  However, these conventional antifogging sheets have insufficient antifogging properties. That is, the anti-fogging sheet has anti-fogging properties (high-temperature anti-fogging property) against water vapor generated from the contents when, for example, high-temperature contents are contained in the container, in particular, the contents containing moisture in the container. When storing (foods etc.) and storing at low temperature, antifogging property (low temperature antifogging property) against water vapor or condensation is low. Further, the antifogging property is greatly reduced by winding the sheet or forming the container. That is, a resin sheet (for example, a styrene resin sheet) used for container molding is, for example, melt-kneaded resin, extruded into a sheet shape, biaxially stretching the formed sheet, and then applying an antifogging agent And dried and wound up into a roll. And in container shaping | molding, the resin sheet is drawn out from the roll and the container is shape | molded by thermoforming. However, with the winding of the resin sheet, the antifogging agent is brought into contact with the non-fogging treated surface of the resin sheet and transferred, and also in the container molding process, the antifogging agent is prevented by contact with a heating body such as a hot plate. The antifogging property and blocking resistance of the resin sheet and container are greatly reduced because of the transfer of the clouding agent. In particular, when a container is formed by deep drawing, the antifogging property is greatly reduced. Further, the molding machine is soiled by the antifogging agent. Furthermore, in order to improve the releasability of the antifogging sheet, a relatively large amount of silicone oil is required.

JP-A-2001-171052 (Patent Document 6) discloses that an antistatic agent containing a fatty acid amide and a polyoxyethylene-polyoxypropylene block copolymer in a specific ratio is applied on at least one surface in an amount of 2 applied. A styrene resin sheet coated at ˜30 mg / m ² is disclosed. This document also describes that the antistatic agent further contains silicone oil, and the coating amount of the silicone oil is 1 to 25 mg / m ² . Japanese Patent Application Laid-Open No. 2002-12686 (Patent Document 7) discloses a coating composition composed of a fatty acid amide, a polyoxyethylene-polyoxypropylene block copolymer, a silicone oil, and a water-soluble blue colorant. A resin sheet coated on the surface with a specific quantitative relationship is disclosed, and the fatty acid amide and the polyoxyethylene-polyoxypropylene block copolymer constitute an antistatic composition.

However, these documents do not describe antifogging properties. In addition, although the antistatic property is improved to some extent in the above sheet, a relatively large amount of silicone oil is required to improve the release property of the sheet.
Japanese Examined Patent Publication No. 63-62538 JP-A-10-309785 Japanese Patent No. 3241797 JP 2003-201335 A (Claim 1 and paragraph number [0005]) JP 2004-238614 A (Claim 1 and paragraph number [0001]) JP 2001-171052 A JP 2002-12686 A

  Accordingly, an object of the present invention is to provide an antifogging surface treatment agent (or antifogging composition) having excellent antifogging properties, an antifogging resin sheet and a method for producing the same, and a container using the antifogging resin sheet. It is to provide.

  Another object of the present invention is to provide an anti-fogging surface treatment agent that suppresses stickiness of the treated surface and is excellent in gloss, an anti-fogging resin sheet and a method for producing the same, and a container using the anti-fogging resin sheet. There is.

  Still another object of the present invention is to provide an antifogging surface treatment agent that can maintain high antifogging properties even when subjected to winding, thermoforming, and the like, and can improve mold releasability (or blocking resistance). An object of the present invention is to provide an antifogging resin sheet using an antifogging surface treatment agent, a method for producing the same, and a container using the antifogging resin sheet.

  Another object of the present invention is to provide an antifogging surface treatment agent that can impart high releasability (or anti-blocking property) even when the amount of silicone oil used is small, and an antifogging agent using this antifogging surface treatment agent. The object is to provide a cloudy resin sheet, a method for producing the same, and a container using the resin sheet.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventor obtained an anti-fogging layer having excellent anti-fogging properties when a resin sheet is coated with a treatment agent containing a specific fatty acid amide and a specific hydrophilic polymer. The present invention has been completed by finding that it can be formed and can impart high antifogging properties to the resin sheet.

That is, the antifogging surface treatment agent of the present invention comprises a fatty acid amide (excluding polyoxyethylene fatty acid amide) (A) and a hydrophilic polymer (provided that polyoxyethylene-polyoxypropylene block copolymer is included). Excluding) (B). The fatty acid amide (A) may be an amide of a C _8-30 fatty acid and an amine (for example, an amide of a C _8-26 fatty acid and a mono or dialkanol amine). The hydrophilic polymer (B) is polyoxyethylene, higher alcohol ethylene oxide adduct, aromatic hydroxy compound ethylene oxide adduct, polyhydric alcohol fatty acid ester ethylene oxide adduct, fat and oil ethylene oxide adduct, It may be at least one selected from vinylpyrrolidone polymers, vinyl alcohol polymers, cellulose ethers, and natural polymer polysaccharides (such as alginic acid or a salt thereof). The ratio (weight ratio) between the fatty acid amide (A) and the hydrophilic polymer (B) is: fatty acid amide (A) / hydrophilic polymer (B) = 1/99 to 80/20 (especially 5/95 to 30/70) or so. The surface treatment agent may further contain silicone oil.

  The present invention also includes an antifogging resin sheet in which an antifogging layer composed of the surface treatment agent is formed on at least one surface of the resin sheet. The resin sheet may be subjected to corona discharge treatment, and an antifogging layer may be formed on the corona discharge treatment surface. An antifogging layer may be formed on one surface of the resin sheet, and a release layer may be formed on the other surface. The release layer may be composed of at least one selected from ether-based hydrophilic polymers having at least oxyethylene units and silicone oil. The resin sheet may be a styrene resin sheet or the like. Such an antifogging resin sheet can be produced by applying the surface treatment agent to at least one surface of the resin sheet. After applying the surface treatment agent to the resin sheet, the antifogging resin sheet may be produced by winding it into a roll.

  The present invention also includes a container formed of the antifogging resin sheet and a container in which an antifogging layer composed of the surface treatment agent is formed on at least a part of the surface of the resin container.

  Note that there is no direct relationship between the antistatic performance and the antifogging performance, and even if the antistatic properties are high, the high antifogging properties cannot be obtained uniquely.

  In the present specification, the term “sheet” is used to mean a two-dimensional structure such as a film or a plate.

  In the antifogging surface treatment agent and antifogging resin sheet of the present invention, a specific fatty acid amide and a specific hydrophilic polymer are combined to improve antifogging properties (high temperature antifogging property and low temperature antifogging property). it can. Moreover, since the stickiness of the surface (processed surface) after processing with a surface treating agent can be suppressed, it is excellent also in transparency and gloss. Therefore, even if the antifogging resin sheet is molded into a container or the like, the contents can be clearly seen without distortion, and the visibility is high. Further, even if the sheet is subjected to winding or thermoforming, it is possible to maintain high antifogging properties and to improve the releasability (or blocking resistance). Further, when silicone oil is used, high releasability (or blocking resistance) can be imparted even if the amount used is small. Moreover, the stain | pollution | contamination of the molding machine by an antifogging agent can be reduced.

[Surface treatment agent]
The antifogging surface treatment agent of the present invention comprises a fatty acid amide (excluding polyoxyethylene fatty acid amide) (A) and a hydrophilic polymer (excluding polyoxyethylene-polyoxypropylene block copolymer). It consists of and.

(A) Fatty acid amide Fatty acid amide (A) is a compound in which the hydrogen atom of amines (amine or ammonia) is substituted with an acid group corresponding to fatty acid (aliphatic carboxylic acid), and as an amide of fatty acid and amines Can be represented. The fatty acid amide (A) may be a C _2-4 alkylene oxide adduct of a fatty acid amide such as a polyoxypropylene fatty acid amide as long as it is other than a polyoxyethylene fatty acid amide, but usually an alkylene oxide is added. Often no fatty acid amide is used.

The fatty acid constituting the fatty acid amide may be either a monocarboxylic acid or a polycarboxylic acid, and may be either a saturated or unsaturated fatty acid. The fatty acid includes a component containing a fatty acid, for example, a component containing a fatty acid as a main component (for example, containing 50% by weight or more) (for example, fats and oils such as coconut oil). The fatty acids are C _6-40 fatty acids, preferably C _8-30 fatty acids (eg C _8-26 fatty acids), more preferably C _10-22 fatty acids (eg C _10-20 fatty acids), in particular C _10-18 saturated. It may be a fatty acid (such as capric acid, lauric acid, myristic acid or a mixture thereof (such as coconut oil fatty acid)).

  The amine constituting the fatty acid amide may be a primary amine (or N-monosubstituted amine) or a secondary amine (or N, N-disubstituted amine), and may be a monoamine or a polyamine. Also good. The fatty acid amide may be either monoamide or polyamide.

Specific examples of fatty acid amides include saturated or unsaturated fatty acid amides such as alkanecarboxylic acid amides (capric acid amide, lauric acid amide, myristic acid amide, palmitic acid amide, stearic acid amide, arachidic acid amide, behenic acid amide, C _8-30 alkane carboxylic acid amides such as montanic acid amide and 12-hydroxystearic acid amide), alkene carboxylic acid amides (such as C _8-30 alkene carboxylic acid amides such as oleic acid amide and erucic acid amide), N- Substituted C _8-30 fatty acid amides [N-substituted saturated or unsaturated fatty acid amides, such as N-alkyl-alkanecarboxylic acid amides (eg, N-methyl lauric acid amide, N-methyl palmitic acid amide, N-palmityl palmitic acid) Acid amide, N, N-dimethyl ester _{N-C 1-26} alkyl _{-C 8-30} alkanecarboxylic acid amide, such as phosphoric acid amide (preferably _{N-C 1-20} alkyl _{-C 8-30} alkanecarboxylic acid amide), etc.), N- alkyl - alkene carboxylic Acid amides (for example, N—C _1-26 alkyl-C _8-30 alkene carboxylic acid amides such as N-methyl oleic acid amide (preferably N—C _1-20 alkyl-C _8-30 alkene carboxylic acid amide, etc.) N-alkenyl-alkanecarboxylic acid amides (N-C _2-26 alkenyl-C _8-30 alkanecarboxylic acid amides such as N-oleyl palmitic acid amide (preferably N—C _2-20 alkenyl-C _8-30 alkanes); N-alkenyl-alkene carboxylic acid amide (N-oleyl oleic acid amide) How _{N-C 2-26} alkenyl _{-C 8-30} alkene carboxylic acid amide (preferably _{N-C 2-20} alkenyl _{-C 8-30} alkene carboxylic acid amide); amides of mono- or poly alkanolamine alkanecarboxylic acids (N- (hydroxy C _1-26 alkyl) -C _8-30 such as N-methylol lauric acid amide, capric acid ethanolamide, lauric acid ethanolamide, lauric acid isopropanolamide, myristic acid ethanolamide, coconut oil fatty acid ethanolamide, etc. alkanecarboxylic acid amides (preferably N- (hydroxy _{C 1-20 alkyl) -C 8-30} alkanecarboxylic acid amide; capric acid diethanolamide, lauric acid diethanolamide, myristic acid diethanolamide, coconut oil fatty acid Jietano Di C _1-10 alkanolamine such as amides (preferably di C _1-6 alkanolamines) amides of the C _8-30 alkanecarboxylic acid); mono- or poly alkanolamine and amides of alkene carboxylic acid (ethanol oleate N- (hydroxy C _8-26 alkyl) -C _{8-30 alkenecarboxylic} acid amides such as amides; diC _1-10 alkanolamines (preferably diC _1-6 alkanolamines) such as oleic acid diethanolamide and C _{8 -30} amides of alkene carboxylic acid); N-aminoalkyl - alkanecarboxylic acid amide (N- (aminomethyl) - lauric acid amide, N- (aminoethyl) - N- such lauric acid amide (amino _{C 1- 26 alkyl) -C 8-30} alkanecarboxylic acid amides (preferably N (Amino _{C 1-20 alkyl) -C 8-30} alkanecarboxylic acid amide), etc.); N-aminoalkyl - alkene carboxylic acid amide (N- (aminoethyl) - N- such as oleic acid amide (amino _{C 1- 26} alkyl) -C _8-30 alkene carboxylic acid amide (such as N- (amino C _1-20 alkyl) -C _8-30 alkene carboxylic acid amide), alkylene bisamide [N, N′-methylene bis (lauric acid amide) ), N, N′-ethylenebis (lauric acid amide), N, N′-ethylenebis (myristic acid amide), N, N′-ethylenebis (stearic acid amide), N, N′-ethylenebis (olein) N, N′-C _1-12 alkylene (or alkylidene) bis (C _8-30 alkanecarboxylic acid amide), etc.] And C _8-30 fatty acid amide.

Fatty acid amides can be used alone or in combination of two or more. Preferred fatty acid amides include C _8-30 fatty acids (eg, C _8-26 fatty acids) and amines (eg, monoalkanolamines, dialkanolamines, trialkanolamines and other polyalkanolamines (particularly mono- or di-C). _1-10 alkanolamine), etc.) and fatty acid amides [e.g., N- (hydroxy _{C 1-10 alkyl) -C 8-30} alkanecarboxylic acid amide (in particular, N- (hydroxy _{C 1-6} alkyl) -C _{8 -30} alkanecarboxylic acid amide), an amide of diC _1-10 alkanolamine and C _8-30 alkanecarboxylic acid (ie, N, N-di ( _{hydroxyC 1-10} alkyl) -C _8-30 alkanecarboxylic acid) Amides (especially N, N-di (hydroxyC _1-6 alkyl) -C _8-30 alkaneca Rubonic acid amide)) and the like]. Among fatty acid amides, in particular, fatty acid amides of C _8-20 saturated fatty acids (such as C _10-16 saturated fatty acids such as capric acid, lauric acid, myristic acid, coconut oil fatty acid) and mono- or di-C _1-4 alkanolamines. Is preferred.

  The molar ratio of the fatty acid to the amine (including ammonia) can be appropriately selected according to the number of carboxyl groups of the fatty acid and the number of active hydrogen atoms of the amine. For example, fatty acid / amines = It may be about 1/5 to 5/1, preferably 1/3 to 3/1, and more preferably about 1/2 to 2/1. For example, in the amide of fatty acid and dialkanolamine and its alkylene oxide adduct, fatty acid and alkanolamine or dialkanolamine were used in a ratio of the former / the latter (molar ratio) = 1/2. A 2-type amide and a 1: 1-type amide used at a ratio of the former / the latter (molar ratio) = 1/1 are included, and any type of amide can be used as the fatty acid amide in the present invention.

(B) Hydrophilic polymer Hydrophilic polymers include hydrophilic groups or units (carboxyl groups or salts thereof, sulfonic acid groups or salts thereof, hydroxyl groups, amide groups, basic nitrogen atom-containing groups, vinyl ether units, oxy Polymer having an ethylene unit), a cellulose derivative, a natural polymer polysaccharide (such as alginic acid), and the like. The hydrophilic polymer may be any of a water-soluble polymer, a water-dispersible polymer, and a water-swellable polymer.

As the hydrophilic polymer, for example, a polymer having a carboxyl group or a salt thereof [for example, a monomer having a carboxyl group such as (meth) acrylic acid, maleic acid, fumaric acid, itaconic acid or a copolymer thereof Also includes copolymers with other copolymerizable monomers such as (meth) acrylic acid esters (such as (meth) acrylic acid C _1-10 alkyl esters), styrene, carboxylic acid vinyl esters (such as vinyl acetate), etc. (E.g., poly (meth) acrylic acid, (meth) acrylic acid-maleic anhydride copolymer, (meth) acrylic acid-vinyl sulfonic acid copolymer, (meth) acrylic acid-methyl methacrylate copolymer, etc. (Meth) acrylic acid polymers) or salts thereof (for example, alkali metal salts such as sodium salts and potassium salts, ammonium salts and organic amine salts). A polymer having a sulfonic acid group or a salt thereof [for example, a monomer having a sulfonic acid group such as ethylene sulfonic acid or styrene sulfonic acid, or a copolymer (with other copolymerizable monomers described above) Or a salt thereof (for example, alkali metal salt such as sodium salt and potassium salt, ammonium salt, organic amine salt and the like)], hydroxyl group-containing polymer [for example, hydroxyl group-containing monomer ( For example, hydroxyalkyl acrylates such as 2-hydroxyethyl acrylate and 2-hydroxypropyl acrylate, hydroxyalkyl methacrylates corresponding to these hydroxyalkyl acrylates, polyethylene glycol mono (meth) acrylates, etc.) or copolymers (the other copolymerizable monomers). Copolymer), vinyl alcohol polymers, etc.], polymers Group-containing polymer [for example, a monomer having an amide group such as (meth) acrylamide or a copolymer (including a copolymer with the other copolymerizable monomer)], basic Nitrogen atom-containing polymer [for example, N-dimethylaminoethyl acrylate, N-diethylaminoethyl acrylate or the corresponding methacrylate, vinyl pyrrolidone or other monomer having a basic nitrogen atom, or a copolymer (the other Including a copolymer with a copolymerizable monomer)], ether group-containing polymer [for example, vinyl ether monomers (vinyl methyl ether, vinyl ethyl ether, vinyl isopropyl ether, vinyl butyl ether, vinyl isobutyl ether, etc.) Of alkyl vinyl ethers) or copolymers (ether group-containing vinyl polymers, For example, other copolymerizable monomers such as polymethyl ether, polyethyl vinyl ether, vinyl ether-maleic anhydride copolymer (monomer having carboxyl group, other copolymerizable monomers exemplified above, etc. ) and a copolymer of), etc.], polyoxyethylene - polyoxypropylene block copolymer than the polymer having an oxyethylene unit, a cellulose derivative [e.g., alkyl celluloses (methyl cellulose, ethyl cellulose, such as cellulose C _{1- 6} alkyl cellulose), hydroxyalkyl cellulose (hydroxyethyl cellulose, hydroxy C _1-6 alkyl cellulose such as hydroxyethyl cellulose), hydroxyalkyl alkylcelluloses (hydroxyethyl cellulose, hydroxy B such hydroxyalkyl _{C 1-6} alkyl _{-C 1-6} alkyl celluloses such as pills), cellulose ethers such as carboxyalkyl cellulose (carboxymethyl cellulose, carboxy _{C 1-6} alkyl celluloses such as carboxymethyl cellulose); soluble cellulose acetate, Inorganic acid esters (cellulose sulfate, cellulose phosphate, etc.)], alginic acid or a salt thereof, and the like. A hydrophilic polymer can be used individually or in combination of 2 or more types.

  Of the hydrophilic polymers, a polymer having an oxyethylene unit, a vinyl pyrrolidone polymer, a vinyl alcohol polymer, cellulose ether, alginic acid or a salt thereof is preferable.

Polymers having oxyethylene units include polymers other than polyoxyethylene-polyoxypropylene block copolymers, such as polyoxyethylene, higher alcohol ethylene oxide adducts (polyoxyethylene dodecyl ether, polyoxyethylene lauryl ether, etc. A polyoxyethylene C _8-26 alkyl ether (preferably C _10-20 alkyl ether), an ethylene oxide adduct of an aromatic hydroxy compound [for example, a polyoxyethylene aryl ether such as polyoxyethylene phenyl ether (preferably polyoxyethylene ethylene C _6-10 aryl ether); polyoxyalkylene alkyl aryl ethers such as polyoxyethylene nonylphenyl ether (preferably polyoxy Styrene C _4-26 alkyl phenyl ether, etc.), etc.], polyvalent ethylene oxide adduct of alcohol fatty acid esters [polyoxyethylene glycerin stearic acid ester, polyoxyethylene sorbitan stearic acid ester, such as poly polyoxyethylene sorbitol stearate C _8-26 fatty acid esters of di- to octa-ol having an oxyethylene chain (preferably such as C _10-20 fatty acid esters of a di- to hexa-ol having a polyoxyethylene chain), etc.], oil ethylene oxide adduct (polyoxy Ethylene castor oil, polyoxyethylene hydrogenated castor oil, ethylene oxide adducts of hydroxyl group-containing fats and oils such as polyoxyethylene coconut oil, and the like. The number average molecular weight of the polyoxyethylene is, for example, 150 or more (for example, 150 to 35,000), preferably 200 to 30,000, and more preferably about 200 to 20,000.

  In the ethylene oxide adduct, the number of moles of oxyethylene units added may be, for example, 2 to 100, preferably 2 to 50, more preferably about 3 to 30.

  The vinyl pyrrolidone-based polymer includes vinyl pyrrolidone or a derivative thereof alone or as a copolymer, for example, polyvinyl pyrrolidone, a copolymer of vinyl pyrrolidone and a copolymerizable monomer (for example, vinyl acetate, vinyl imidazole, and / or Or a copolymer with vinylcaprolactam or the like). The vinyl pyrrolidone polymers can be used alone or in combination of two or more. The proportion of vinylpyrrolidone or a derivative thereof in the vinylpyrrolidone polymer may be, for example, 30 to 100% by weight, preferably 50 to 95% by weight, and more preferably about 60 to 90% by weight. When the ratio of vinylpyrrolidone or a derivative thereof is 30% by weight or more, it is advantageous in terms of antifogging property.

  Examples of the vinyl alcohol polymer include saponification products of vinyl ester polymers (single or copolymer), such as polyvinyl alcohol (fully saponified polyvinyl alcohol, partially saponified polyvinyl alcohol), partially acetalized polyvinyl alcohol, ethylene- Examples thereof include a vinyl alcohol copolymer, a vinyl alcohol-ethylene sulfonic acid copolymer, and a vinyl alcohol-maleic acid copolymer.

  The saponification degree of the vinyl alcohol polymer is not particularly limited, but is, for example, 60 to 100 mol%, preferably 70 to 100 mol% (for example, 80 to 99 mol%), more preferably about 85 to 100 mol%. There may be.

  The degree of polymerization (or average degree of polymerization) of the vinyl alcohol polymer may be, for example, 100 or more (e.g., 100 to 5000, preferably 200 to 4000, more preferably about 500 to 3000).

The polymerization degree (or average polymerization degree) of cellulose ether is usually 100 or more (for example, 100 to 2000), preferably 150 to 1000, more preferably about 200 to 800. Wherein one of the cellulose ethers, in particular, _{C 1-4} alkyl celluloses such as methyl cellulose, hydroxyalkyl _{C 1-4} alkyl celluloses, hydroxyethyl cellulose such as hydroxyethyl cellulose, hydroxypropyl _{C 1-4} alkyl _{-C 1-4} such as hydroxypropylmethyl cellulose Carboxy C _1-4 alkyl cellulose such as alkyl cellulose and carboxymethyl cellulose is preferred.

  Examples of the natural polymer polysaccharide include alginic acid or a salt thereof, pectin, starch, hyaluronic acid, sodium chondroitin sulfate, chondroitin heparin, agar, gum arabic, dextrin and the like. Of these polysaccharides, alginic acid or a salt thereof is particularly preferable.

  Alginic acid is a linear polymer polysaccharide obtained by extraction from brown algae plants such as kombu, wakame and kajime, and is a heteropolymer containing D-mannuronic acid and L-guluronic acid as constituent units. . Examples of the salt of alginic acid include a salt of alginic acid and an inorganic base. Specifically, ammonium salt; alkali metal salt such as potassium salt and sodium salt; alkaline earth metal salt such as calcium salt and magnesium salt; silver Examples thereof include transition metal salts such as salts and copper salts. Of these salts, monovalent metal salts (such as alkali metal salts) are preferable in addition to ammonium salts.

  In alginic acid or a salt thereof, the polymerization degree (or average polymerization degree) of alginic acid is usually 20 or more (for example, 20 to 2000), preferably 50 to 1500, and more preferably about 70 to 1300.

  The ratio (weight ratio) between the fatty acid amide (A) and the hydrophilic polymer (B) can be selected from fatty acid amide (A) / hydrophilic polymer (B) = 1/99 to 99/1, 1/99 to 80/20 (eg 2/98 to 60/40), preferably 5/95 to 50/50 (eg 5/95 to 30/70), more preferably 7/93 to 25/75 (For example, about 10/90 to 20/80).

(Silicone oil)
The surface treatment agent may contain silicone oil. When silicone oil is used, the antiblocking property or release property of the resin sheet (antifogging resin sheet) to which the surface treatment agent is applied can be improved. The type of silicone oil is not particularly limited. For example, alkylpolysiloxanes such as dimethylpolysiloxane, diethylpolysiloxane, and trifluoropropylpolysiloxane; arylpolysiloxanes such as diphenylpolysiloxane; alkylarylpolysiloxanes such as methylphenylpolysiloxane Etc. The silicone oil may be a chain polysiloxane or a cyclic polysiloxane.

Furthermore, the silicone oil is a modified silicone oil such as a hydroxyalkyl group (such as a hydroxy _C2-4 alkyl group such as a hydroxyethyl group), a polyoxyalkylene group, an amino group, an N-alkylamino group, a glycidyl group or an epoxy group. Or a silicone oil having a polymerizable group (such as a vinyl group or a (meth) acryloyl group).

  Silicone oils can be used alone or in combination of two or more. Of silicone oils, dimethylpolysiloxane having high versatility is usually used. Silicone oil can be used in various forms, but is usually used in the form of a silicone emulsion (emulsion in which silicone oil is emulsified and dispersed).

The viscosity of the silicone oil is not particularly limited. For example, Ostwald viscosity at room temperature (15 to 25 ° C.) is 50 to 50000 centistokes (0.5 × 10 ^{−4 to} 500 × 10 ⁻⁴ m ² / s), preferably 100 to 30000 centistokes (1 × 10 ^{−4 to} 300 × 10 ⁻⁴ m ² / s), more preferably 150 to 25000 centistokes (1.5 × 10 ⁻⁴ to 250 × 10 ⁻⁴ m ² / s) It may be a degree.

  The amount of silicone oil used is, for example, 0.1 to 40 parts by weight, preferably 1 to 30 parts by weight, more preferably 100 parts by weight of the total amount of fatty acid amide (A) and hydrophilic polymer (B). It may be about 5 to 25 parts by weight.

  The surface treatment agent may contain a polyhydric alcohol and / or a fatty acid ester of a polyhydric alcohol as necessary.

Examples of the polyhydric alcohol include C _2-12 alkylene glycols such as ethylene glycol, propylene glycol, butanediol, hexanediol, and neopentyl glycol; diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, poly (Poly) oxy C _2-4 alkylene glycol such as tetramethylene glycol; glycerin, polyglycerin having a polymerization degree of about 2 to 20 (diglycerin, triglycerin, tetraglycerin, polyglycerin, etc.), trimethylolethane, trimethylolpropane, Polyhydrides such as pentaerythritol and saccharides (sucrose, sorbitol, mannitol, xylitol, maltitol, sorbitan, oligosaccharide, etc.) Alkoxy compounds (polyhydric alcohols), and others. These polyhydric alcohols can be used alone or in combination of two or more.

Examples of fatty acid esters of polyhydric alcohols include esters of the above polyhydric alcohols and various fatty acids. Specific examples include sucrose fatty acid esters (for example, sucrose mono to hexalaurate, sucrose mono to hexa Stearates, mono- or _hexaesters of sucrose and C _8-24 saturated or unsaturated fatty acids such as sucrose mono to hexaoleate, etc., polyglycerin fatty acid esters (polyglycerin having a degree of polymerization of about 2 to 16) And C _8-24 saturated or unsaturated fatty acid mono to dodecaesters, for example, decaglycerin mono to decaprylic acid ester, hexaglycerin mono to pentalauric acid ester, decaglycerin mono to decalauric acid ester, decaglycerin mono to deca Stearic acid ester Such as decaglycerol mono- to Dekaorein esters), mono- to tri-esters of glycerol fatty acid ester (glycerol and C _8-24 saturated or unsaturated fatty acids, for example, glycerin mono- to tricaprylate ester, glycerin mono- to trilaurate esters, glycerin Mono to tristearic acid ester, glycerin mono to trioleic acid ester, etc.), sorbitol fatty acid ester (mono to _{hexaesters of} sorbitol and C _8-24 saturated or unsaturated fatty acid, for example, sorbitol mono to hexacaprylate, Sorbitol mono to hexalaurate, sorbitol mono to hexastearate, sorbitol mono to hexaoleate, etc.). These fatty acid esters can be used alone or in combination of two or more.

  The total amount of polyhydric alcohol and polyhydric alcohol fatty acid ester is 0.1 to 100 parts by weight (for example, 0 to 100 parts by weight of the total amount of fatty acid amide (A) and hydrophilic polymer (B)). .3 to 80 parts by weight), preferably 0.5 to 50 parts by weight (for example, 1 to 30 parts by weight), more preferably about 1 to 10 parts by weight (for example, 2 to 5 parts by weight). . Moreover, the surface treating agent which does not contain a polyhydric alcohol and a polyhydric alcohol fatty acid ester substantially is also preferable.

  Surface treatment agents include various additives such as stabilizers (antioxidants, UV absorbers, etc.), fillers, colorants, antistatic agents, flame retardants, lubricants, waxes, preservatives, viscosity modifiers, increase agents. It may contain a sticking agent, leveling agent, antifoaming agent and the like. Further, the surface treatment agent can be usually used in the form of a coating solution or an impregnation solution, and may be a non-aqueous liquid composition using an organic solvent as a solvent, but is usually used as an aqueous composition. In the aqueous composition, the solvent may be water alone, water and a hydrophilic solvent (especially a water miscible solvent) [for example, alcohols (methanol, ethanol, isopropanol, etc.), ketones (acetone, etc.), A mixed solvent with ethers (dioxane, tetrahydrofuran, etc.), cellosolves (methyl cellosolve, ethyl cellosolve, butyl cellosolve, etc.), carbitols, etc.] may be used.

  The surface treatment agent can be prepared by using a conventional mixing stirrer or mixing / dispersing machine, and the silicone oil may be dispersed along with the preparation. The viscosity of the surface treatment agent can be appropriately selected as long as the coating property is not impaired. The viscosity of the surface treatment agent is, for example, 5000 cps (= 5 Pa · s) or less, preferably 10 to 3000 cps (= 0.01 to 3 Pa · s), more preferably 100 to 2500 cps (= 0.1 to 2.5 Pa · s). s) degree may be sufficient.

[Anti-fogging resin sheet and manufacturing method thereof]
The antifogging resin sheet of the present invention comprises a resin sheet and an antifogging layer (a coating layer or a coating layer) formed on at least one surface (one surface or both surfaces) of the resin sheet. The cloud layer is composed of the surface treatment agent.

  The resin sheet may be various thermoplastic resins having film or sheet moldability, such as polyethylene resin (polyethylene, ethylene-ethyl acrylate copolymer, ionomer, etc.), polypropylene resin (polypropylene, propylene-ethylene copolymer). ), Olefin resins such as poly-4-methylpentene-1; vinyl alcohol resins such as polyvinyl alcohol and ethylene-vinyl alcohol copolymer; vinyl chloride resins such as polyvinyl chloride; styrene resins; polyethylene terephthalate Homo or copolyester resins having an alkylene arylate unit such as polybutylene terephthalate; nylon or polyamide resins; polyacrylonitrile resins; polycarbonate resins; polyphenylene oxide resins; Risuruhon resins; can be formed by cellulose derivatives and the like. These resins can be used alone or in combination of two or more. The resin sheet may be a single layer sheet or a laminated sheet in which a plurality of resin layers are laminated. The thickness of the resin sheet can be appropriately selected depending on the application, and is, for example, about 10 μm to 5 mm, preferably about 25 μm to 1 mm. When used for container molding, the thickness of the resin sheet may be, for example, 50 μm to 2 mm, preferably 50 to 1000 μm (for example, 100 to 1000 μm), and more preferably about 130 to 500 μm.

  A preferable resin sheet is a sheet having moldability, particularly a hydrophobic synthetic resin sheet, and can be composed of, for example, an olefin resin (particularly polypropylene resin), a polyester resin (particularly polyethylene terephthalate resin), or a styrene resin. . In particular, a resin sheet having high moldability, for example, a styrene resin sheet is preferable. The polystyrene sheet is highly transparent.

  Styrenic resins include homopolymers containing aromatic vinyl monomers (such as styrene, vinyltoluene, and α-methylstyrene) as constituents, and copolymerization of aromatic vinyl monomers and copolymerizable monomers. Combinations and mixtures thereof are included. More specifically, examples of the styrene resin include general-purpose polystyrene (GPPS), rubber-reinforced polystyrene (high impact polystyrene: HIPS), polystyrene-polybutadiene-polystyrene block copolymer, acrylonitrile-styrene copolymer (AS). Resin), acrylonitrile-butadiene-styrene copolymer (ABS resin), styrene-butadiene block copolymer, rubber component X (acrylic rubber, chlorinated polyethylene, ethylene-propylene rubber (EPDM), ethylene-vinyl acetate copolymer) AXS resin obtained by graft polymerization of acrylonitrile A and styrene S, styrene-methyl methacrylate copolymer, acrylonitrile-styrene-methyl methacrylate copolymer, and the like. These styrenic resins can be used alone or in admixture of two or more.

  Resin sheets are made of various additives such as stabilizers (antioxidants, UV absorbers, heat stabilizers, etc.), antistatic agents, crystal nucleating agents, hydrocarbon polymers, plasticizers, mineral oil, filling An agent, a coloring agent, etc. may be included.

  The resin sheet can be obtained by a conventional method, for example, a conventional film forming method such as a T-die method or an inflation method. The resin sheet may be unstretched, but is preferably stretched. The stretched film may be a uniaxially stretched film, but is preferably a biaxially stretched film. Moreover, you may heat-process (heat-setting process) a stretched film as needed. Examples of the stretching method include conventional stretching methods such as roll stretching, roll stretching, belt stretching, tenter stretching, tube stretching, and stretching methods combining these. The draw ratio can be appropriately set according to the desired sheet properties, and may be, for example, 1.2 to 20 times, preferably 1.5 to 15 times, and more preferably about 2 to 10 times.

The surface of the resin sheet may be subjected to a conventional surface treatment such as corona discharge treatment or high frequency treatment. In particular, the resin sheet is preferably subjected to corona discharge treatment to form an antifogging layer on the corona discharge treatment surface. The surface tension of the resin sheet varies depending on the type of the sheet and cannot be determined unconditionally. However, when measured in accordance with JIS K-6768 “wetting test method for polyethylene and polypropylene films”, the surface tension is 30 to 65 dyn / cm (30 × 10 ^{−5 to} 65 × 10 ⁻⁵ N / cm). In the case of a styrene resin sheet, the surface tension is 40 to 62 dyn / cm (40 × 10 ^{−5 to} 62 × 10 ⁻⁵ N / cm), preferably 42 to 62 dyn / cm (42 × 10 ^{−5 to} 62 × 10 ^{− 5} N / cm), more preferably about 45 to 60 dyn / cm (45 × 10 ^{−5 to} 60 × 10 ⁻⁵ N / cm).

  If the surface tension of the sheet surface is too high, the sheet surface is activated too much, or blocking is likely to occur. Therefore, it becomes difficult to rewind a sheet wound in a roll shape, or when a plurality of molded containers are stacked and punched out, the containers are brought into close contact with each other, and the work efficiency of separating the containers and storing the contents decreases. easy.

  The anti-fogging resin sheet of the present invention in which the anti-fogging layer is formed is excellent in transparency and surface appearance (such as gloss), and after being wound into a roll or after forming (for example, after deep drawing). Has high antifogging properties. Furthermore, the contamination of the molding machine by the antifogging agent can be reduced.

The coating amount of the surface treatment agent (coating amount after drying) is, for example, be selected from a wide range of about 5 to 150 mg / ^{m 2,} typically, 10-100 mg / ^{m 2,} preferably 15~80mg / ^{m 2} (e.g. 20 to 70 mg / m ² ), more preferably about ²⁰ to 50 mg / m ^2, or an application amount of about 10 to 50 mg / m ² .

  In the antifogging resin sheet of the present invention, at least one surface of the resin sheet may be treated with a surface treatment agent, one surface is treated (or applied) with the surface treatment agent, and the other surface is treated with various kinds of materials. You may process (or application | coating treatment) with a processing agent (For example, the anti-blocking agent for improving blocking resistance, the antistatic agent for improving antistatic property and slipperiness, the coating agent containing a lubricant, etc.). In particular, a coating layer of the surface treatment agent may be formed on one surface of the resin sheet, and a release layer (or anti-blocking layer) may be formed on the other surface.

  The release layer (or anti-blocking layer) may be composed of various release agents (or anti-blocking agents) such as wax (including mineral wax, plant wax, synthetic wax, etc.) It is preferable to use at least silicone oil. Furthermore, a preferable release layer can be composed of at least an ether-based hydrophilic polymer having an oxyethylene unit and silicone oil. In addition, as a silicone oil, the same silicone oil (dimethyl polysiloxane etc.) as the above can be used. Further, as the ether-based hydrophilic polymer having an oxyethylene unit, a nonionic surfactant such as a polyoxyethylene-polyoxypropylene block copolymer, a nonionic surfactant having an oxyethylene unit, or the like can be used. .

  In a preferred embodiment, the silicone oil can be used in the form of an emulsion (aqueous emulsion) as described above. The ether-based hydrophilic polymer may be composed of at least one selected from a polyoxyethylene-polyoxypropylene block copolymer and a nonionic surfactant having an oxyethylene unit. Often composed of block copolymers.

  In the release agent, the proportion of the ether-based hydrophilic polymer can be selected within a range that does not impair the antifogging property and blocking resistance, and can be selected from a range of about 0 to 1000 parts by weight with respect to 100 parts by weight of the silicone oil. Usually, it may be about 10 to 500 parts by weight, preferably 20 to 200 parts by weight (for example, 50 to 150 parts by weight), more preferably about 30 to 100 parts by weight (for example, 50 to 100 parts by weight).

  The processing agent such as a release agent is various additives such as stabilizers (antioxidants, ultraviolet absorbers, etc.), fillers, colorants, antistatic agents, flame retardants, lubricants, waxes, preservatives. Further, it may contain a viscosity modifier, a thickener, a leveling agent, an antifoaming agent and the like. The treatment agent can be usually used in the form of a coating solution or an impregnation solution, and may be a non-aqueous liquid composition using an organic solvent as a solvent, but is usually used as an aqueous composition. In the aqueous composition, the solvent may be water alone or a mixed solvent of water and the above-mentioned hydrophilic solvent (especially water-miscible solvent).

The coating amount of the treating agent (the coating amount after drying) can be selected from a wide range of about 1 to 200 mg / m ² (for example, 5 to 100 mg / m ² ) depending on the type of the treating agent, and usually 2 to 100 mg / ^{m 2,} preferably from 3 to 50 mg / ^{m 2} (e.g., 5~30mg ^{/ m} 2), more preferably about 5 to 25 mg / ^{m 2.}

  The antifogging resin sheet can be produced by applying the surface treatment agent (or antifogging agent) to at least one surface of the resin sheet. Further, an antifogging resin sheet is produced by applying the surface treatment agent on one surface of the resin sheet and applying the treatment agent (for example, a mold release agent or an antiblocking agent) on the other surface. May be. For the application of the surface treatment agent (or treatment agent), conventional application means such as spray, roll coater, gravure roll coater, knife coater, dip coater and the like can be used. If necessary, the surface treatment agent (or treatment agent) may be applied a plurality of times. After the surface treatment agent (and treatment agent) is applied to the resin sheet, the antifogging layer and the treatment layer (such as a release layer) can be usually formed by drying the coating layer.

  The antifogging resin sheet may be continuously provided in a post-treatment process (such as a container molding process), but is usually wound in a roll and is often provided in a post-treatment process. Even with such winding, the anti-fogging component transfer can be greatly suppressed due to high blocking resistance, and not only high temperature antifogging property but also low temperature antifogging property is maintained, and high antifogging property is maintained over a long period of time. it can. Further, stickiness and whitening can be suppressed, and the transparency and gloss of the resin sheet are not impaired. Therefore, it can be used for various uses, for example, a cover sheet (or film), a packaging sheet (or film) such as food packaging. A coated resin sheet using a resin sheet having high moldability has high secondary moldability and is suitable for molding processing of containers and the like.

[Container and its manufacturing method]
The container of the present invention is composed of a resin container and an antifogging layer formed on at least a part of the surface of the container, and the antifogging layer is composed of the surface treatment agent. Since such a container is excellent in anti-fogging property and transparency, it is useful as a container for storing a contained material containing moisture such as a food packaging container.

  Moreover, the container usually has at least a container main body for accommodating a container such as food, and the opening of the container main body may be covered with a wrapping film. Moreover, you may comprise a container with a container main body and the cover body which covers the opening part of the said container main body through a hinge part.

  The container of the present invention is only required to have an antifogging layer formed on at least a part of the surface of the resin container (for example, the inner surface or the outer surface of the container body, the inner surface or the outer surface of the lid). It may be a container obtained by applying a surface treatment agent on the surface by spraying or the like, and a container formed of the antifogging resin sheet (such as a container obtained by molding the antifogging resin sheet). It may be. As the resin constituting the resin container, the resins exemplified in the section of the resin sheet can be used.

  A container in which an antifogging layer is formed on the surface of a resin container by applying a surface treatment agent is applied to the surface of the resin container by the application method exemplified in the section of the antifogging resin sheet. It is possible to manufacture by preferably applying by spraying or the like on at least the inner surface of the container body. Moreover, in the molded article which has a cover body, you may process the inner surface of a cover body with the said surface treating agent.

  In many cases, a container formed of an antifogging resin sheet is formed from the antifogging resin sheet by a conventional thermoforming method. Examples of the thermoforming method (or secondary forming process) include a blow molding method, a vacuum forming method, a pressure forming method (a heating / pressure forming method such as a hot plate heating type pressure forming method, a radiation heating type pressure forming method), a vacuum, and the like. A pressure forming method, a plug assist forming method, a matched mold forming method and the like can be used. When using a stretched resin sheet, a hot plate heating type pressure forming method is usually used in many cases.

  In this invention, even if it uses for such thermoforming (secondary shaping | molding), high anti-fogging property and transparency can be maintained. In particular, even when the antifogging resin sheet is deep-drawn, not only the high temperature antifogging property but also the low temperature antifogging property is excellent, and high antifogging property can be maintained.

  Since the antifogging surface treatment agent of the present invention is excellent in antifogging property, it is useful for obtaining an antifogging resin sheet by applying it to a resin sheet by coating or the like. Moreover, even if it uses for secondary shaping | molding (for example, thermoforming) etc., anti-fogging resin sheet can ensure high transparency and glossiness, maintaining anti-fogging property. Further, a container having an antifogging layer formed with an antifogging surface treatment agent (a container formed with the antifogging resin sheet, obtained by applying an antifogging surface treatment agent to the surface of a resin container. And the like) are excellent in transparency and anti-fogging properties, and the visibility of the contents (or contents) is also high. For this reason, the container of the present invention is suitable for storing various items (contents), particularly, items containing moisture (such as food), and is used in an environment where condensation is likely to occur (for example, at low temperatures). It is also useful as a container for storing cooked foods as well as fresh foods and cooked foods to be stored.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples.

  In the examples and comparative examples, the following components (A) to (D) were used.

(A) Fatty acid amide
(A1) Lauric acid diethanolamide (manufactured by Sanyo Chemical Industries, Prophan AA-62EX, lauric acid: diethanolamide = 1 type)
(A2) Coconut oil fatty acid diethanolamide (manufactured by Sanyo Chemical Industries, Profan Extra 24, palm oil fatty acid: diethanolamide = 1 type)
(A3) Coconut oil fatty acid monoethanolamide (manufactured by Sanyo Chemical Industries, Prophan AB-20, Coconut oil fatty acid: monoethanolamide = 1 type)
(A4) Coconut oil fatty acid diethanolamide (manufactured by Sanyo Chemical Industries, Profan 2012E, palm oil fatty acid: diethanolamide = 1: 2 type)
(A5) Lauric acid monoisopropanolamide (manufactured by Sanyo Chemical Industries, Ltd., Prophan AD-31, lauric acid: monoisopropanolamide = 1 type).

(B) Hydrophilic polymer
(B1) Polyoxyethylene (manufactured by Sanyo Chemical Industries, polyethylene glycol PEG6000P, number average molecular weight 6000)
(B2) Polyvinylpyrrolidone (manufactured by BASF Japan Ltd., Rubytec K-90, weight average molecular weight 90 × 10 ^{4 to} 150 × 10 ⁴ )
(B3) Polyvinyl alcohol (manufactured by Kuraray Co., Ltd., Poval PVA117)
(B4) Methylcellulose (manufactured by Shin-Etsu Chemical Co., Ltd., Metroz SM100)
(B5) Carboxymethyl cellulose (manufactured by Daicel Chemical Industries, CMC Daicel 1260)
(B6) Sodium alginate (manufactured by Kibun Food Chemifa Corporation, Duck Algin NSPH).

(C) Silicone oil Dimethyl silicone aqueous emulsion, manufactured by Shin-Etsu Chemical Co., Ltd., KM9738, viscosity 100,000 centistokes = 100 × 10 ⁻⁴ m ² / s
(D) Other ingredients
(D1) Sucrose fatty acid ester (Rikenmar A, manufactured by Riken Vitamin Co., Ltd.)
(D2) Decaglycerin monolauric acid ester (manufactured by Sakamoto Pharmaceutical Co., Ltd., SY Glysta ML750)
(D3) manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Epan U108, weight average molecular weight 18000, ethylene oxide content 80% by weight.

Examples 1-15 and Comparative Examples 1-4
An aqueous surface treatment agent (antifogging treatment agent) containing each component was prepared at a ratio (parts by weight) shown in the table. A biaxially stretched polystyrene sheet having a sheet thickness of 0.25 mm is subjected to corona discharge treatment at 60 dyn / cm (60 × 10 ⁻⁵ N / cm), and the coating amount after drying the antifogging treatment agent is 15 mg / m ^2. The film was coated with a wire brush and dried to form an antifogging layer.

  The properties (initial properties) of the obtained antifogging resin sheet and the properties of the sheets after the antifogging resin sheets were laminated and pressed (characteristics after pressing) were evaluated as follows.

(1) Initial characteristics of anti-fogging resin sheet
(i) High-temperature anti-fogging property A sheet was placed on the opening of a container containing hot water of 60 ° C. so that the anti-fogging layer of the anti-fogging resin sheet was in contact with the vapor, and left for 2 minutes in a room temperature environment. Next, the steam contact portion of the sheet is placed on a character group “antifogging” having a different font size printed on paper, and the degree of fogging of the sheet is visually evaluated according to the following criteria, and about five sheets The average value of the evaluated results was calculated.
5: “Anti-fogging” character with font size 5 can be clearly read 4: “Anti-fogging” character with font size 10 can be clearly read 3: “Anti-fogging” character with font size 14 can be clearly read Readable 2: Font size 18 “anti-fogging” characters can be clearly read 1: Characters cannot be identified.

(ii) Low-temperature anti-fogging property At a surrounding temperature of 23 ° C., a sheet containing water (23 ° C.) is placed with the anti-fogging layer of the anti-fogging resin sheet facing the opening of the container. It put in a 5 degreeC thermostat and left to stand for 2 minutes. Next, the degree of fogging of the sheet immediately after taking out was evaluated in the same manner as in the high temperature antifogging property (i), and the average value of the results of evaluation for 5 sheets was calculated.

(iii) Appearance The appearance of the antifogging resin sheet was visually observed and evaluated according to the following criteria.
○: Glossy, uniform and free of dirt and unevenness ×: Whitely dusty and uneven

(iv) Stickiness The antifogging resin sheet was sandwiched between fingers, and the adhesion of the sheet to the fingers was evaluated according to the following criteria.
○: There is no adhesion to the finger and it is dry. ×: There is an adhesion to the finger.

(2) Sheet characteristics after pressing The antifogging resin sheet is cut into a 30 cm × 30 cm square, and 10 sheets are stacked, and then pressed for 1 hour at a temperature of 40 ° C. and a load of 10 kgf / cm ² (≈98 N / cm ² ). Then, the pressure was released to separate the sheets one by one, and the appearance and high temperature antifogging property of the sheet were evaluated according to the following, and used as an index of sheet characteristics when the sheet was wound into a roll.

(i) Appearance The appearance of the sheet was visually evaluated according to the following criteria.
○: No antifogging treatment agent on the surface of the sheet, and there is no difference in the appearance of the sheet before and after pressing. X: The antifogging agent on the surface of the sheet is offset, and a non-uniformly whitish portion is formed. .

(ii) High-temperature antifogging property The separated sheet after pressing was operated in the same manner as the evaluation of the high-temperature antifogging property (i) in the initial characteristics of the antifogging resin sheet, And an average value of five sheets was calculated.
5: “Anti-fogging” character with font size 5 can be read 4: “Anti-fogging” character with font size 10 can be read 3: “Anti-fogging” character with font size 14 can be read 2: Font size 18 The “anti-fogging” character of 1 can be read 1: the character cannot be identified.

  Table 1 shows the results obtained in the examples and comparative examples.

  As is clear from Table 1, the antifogging resin sheets of the examples had high antifogging properties (high temperature and low temperature antifogging properties), excellent aesthetic appearance (appearance), and no sticky feeling as compared with the comparative examples. On the other hand, in Comparative Example 1, the antifogging property was low and the appearance was cloudy white, and in Comparative Examples 2 to 4, the antifogging property was low and there was a sticky feeling. Moreover, in the comparative example, the processing agent was offset by the press, the appearance was impaired, and the antifogging property after the press was low.

Claims (16)

  Antifogging property composed of fatty acid amide (excluding polyoxyethylene fatty acid amide) (A) and hydrophilic polymer (excluding polyoxyethylene-polyoxypropylene block copolymer) (B) Surface treatment agent. The surface treating agent according to claim 1, wherein the fatty acid amide (A) is an amide of a _C8-30 fatty acid and an amine. The surface treating agent according to claim 1 or 2, wherein the fatty acid amide (A) is an amide of a _C8-26 fatty acid and a mono- or dialkanolamine.   Hydrophilic polymer (B) is polyoxyethylene, higher alcohol ethylene oxide adduct, aromatic hydroxy compound ethylene oxide adduct, polyhydric alcohol fatty acid ester ethylene oxide adduct, oil and fat ethylene oxide adduct, vinyl The surface treating agent according to any one of claims 1 to 3, which is at least one selected from pyrrolidone polymers, vinyl alcohol polymers, cellulose ethers, and natural polymer polysaccharides.   The ratio (weight ratio) between the fatty acid amide (A) and the hydrophilic polymer (B) is fatty acid amide (A) / hydrophilic polymer (B) = 1/99 to 80/20. The surface treating agent according to any one of the above.   The ratio (weight ratio) between the fatty acid amide (A) and the hydrophilic polymer (B) is fatty acid amide (A) / hydrophilic polymer (B) = 5/95 to 30/70. The surface treating agent according to any one of the above.   Furthermore, the surface treating agent of any one of Claims 1-6 containing a silicone oil.   The anti-fogging resin sheet in which the anti-fogging layer comprised with the surface treating agent in any one of Claims 1-7 is formed in the at least one surface of the resin sheet.   The antifogging resin sheet according to claim 8, wherein the resin sheet is subjected to corona discharge treatment, and an antifogging layer is formed on the corona discharge treatment surface.   The antifogging resin sheet according to claim 8 or 9, wherein an antifogging layer is formed on one surface of the resin sheet, and a release layer is formed on the other surface.   The antifogging resin sheet according to claim 10, wherein the release layer is composed of at least one selected from an ether-based hydrophilic polymer having at least an oxyethylene unit and silicone oil.   The antifogging resin sheet according to any one of claims 8 to 11, wherein the resin sheet is a styrene resin sheet.   The manufacturing method of the anti-fogging resin sheet which apply | coats the surface treating agent in any one of Claims 1-7 to the at least one surface of a resin sheet.   The method for producing an antifogging resin sheet according to claim 13, wherein the surface treatment agent according to any one of claims 1 to 7 is applied to the resin sheet and then wound up into a roll.   A container formed of the antifogging resin sheet according to any one of claims 8 to 11.   A container in which an antifogging layer composed of the surface treatment agent according to any one of claims 1 to 7 is formed on at least a part of a surface of a resin container.