JP2001164012A - Antifogging rubber-modified styrene-based resin sheet and molded product thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject resin sheet of high antifoggingness and toughness excellent in the workability in preparing the antifogging agent therefor, and to obtain a molded product using the above resin sheet. SOLUTION: This sheet is obtained by surface treatment of a rubber-modified styrene-based resin sheet with an antifogging agent comprising 10-99.5 mass % of an anionic surfactant and 90-0.5 mass % of a nonionic surfactant; wherein a sulfate salt accounts for >=30 mass % of the anionic surfactant. The other objective molded product is obtained using the above sheet.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rubber-modified styrene resin sheet which is excellent in workability and antifogging property when preparing a solution for treating an antifogging agent, and which is excellent in toughness, and a molded article thereof.
More specifically, styrene resin sheets widely used in the field of packaging materials, etc., have superior handling properties when preparing antifogging agent solutions applied to styrene transparent resin sheets, and have even better antifogging effects. The present invention relates to a rubber-modified styrenic resin sheet that imparts a toughness effect and a molded article thereof.

[0002]

2. Description of the Related Art Styrene resin sheets and molded products are widely used as packaging and coating materials, but due to the hydrophobic nature of the surface, water that has aggregated due to changes in temperature or humidity becomes minute water droplets and adheres to the surface. So-called clouding may occur. The fogging makes it difficult to identify the stored items, which reduces the commercial value, and often causes the coagulated or attached moisture to fall into the stored items due to vibration, resulting in poor quality and decay. In addition, in the process of processing a styrene-based resin sheet into a molded product, when the molded products are overlapped and trimmed, the molded product often cracks and causes a decrease in productivity.

To solve this problem, Japanese Patent Publication No. Sho 59-1
No. 9584 discloses an antifogging agent comprising a surfactant having an HLB of 13 or more and a sucrose higher fatty acid ester.
Japanese Patent No. 221661 discloses an attempt to improve the antifogging property by using an antifogging agent comprising a sucrose fatty acid ester and an anionic surfactant. Japanese Patent Application Laid-Open No. 8-15739 has attempted to improve the antifogging property with an antifogging agent comprising a sucrose fatty acid ester, a hydrophilic polymer and a polyhydric alcohol. JP-B-59-19584 and JP-A-9-22
The anti-fogging agent of JP-A-1661 is inferior in anti-fogging property, and JP-A-8-157639 discloses that hydroxyethyl cellulose is difficult to dissolve and is inferior in handling property when dissolving.
Further, even if an aqueous solution of hydroxyethyl cellulose is prepared in advance to facilitate dissolution, a 15% aqueous solution at a temperature of 25 ° C. has a very high viscosity and is inferior in handleability. In addition, moldability is likely to occur and storage stability is inferior, so that workability, anti-fogging property and toughness are not yet sufficient.

[0004]

SUMMARY OF THE INVENTION Under the above technical situation, the present invention is directed to a rubber-modified styrene which is excellent in workability and antifogging property when preparing an antifogging agent treatment solution, and is also excellent in toughness. It is an object to provide a base resin sheet and a molded product thereof.

[0005]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have reached the present invention by using an antifogging agent having a specific constitution. . That is, the present invention provides an anionic surfactant 10
曇 99.5% by mass and 90 to 0.5% by mass of a nonionic surfactant, wherein 30% by mass or more of the anionic surfactant in the antifogging agent is a sulfate ester salt. The present invention relates to an antifogging rubber-modified styrenic resin sheet obtained by subjecting a rubber-modified styrenic resin sheet to surface treatment with an antifogging agent, and a molded article obtained by using the sheet.

Hereinafter, the present invention will be described in detail. The anti-fogging agent of the present invention comprises an anionic surfactant essentially containing a sulfate ester salt and a nonionic surfactant. Specific examples of the sulfate salt include a compound comprising a sulfate having the following structural formula and a basic substance constituting a salt described below.

[0007]

Embedded image (Wherein, R represents an alkyl group of H and C ₁ ~C _20, n is 0
Represents an integer of 50)

Examples of the basic substance constituting the salt include alkali metals such as sodium and potassium, alkaline earth metals such as magnesium, alkanolamines such as ethanolamine, and lower alkylamines such as tributylamine.

[0009] Examples of these sulfates include coconut alkyl ether sulfate Na, coconut alkyl sulfate Na, triethanolamine lauryl sulfate and the like. At least one of these can be used.

Further, the anti-fogging agent of the present invention may be used in combination with other anionic surfactants such as carboxylate, sulfonate and phosphate ester salt. At that time, the content of the sulfate in the total anionic surfactant is 30% by mass or more. It is preferably at least 50% by mass, more preferably at least 70% by mass. If the amount of the sulfate is less than 30% by mass, the antifogging property is poor. Examples of the carboxylate include K laurate, Na myristate, K palmitate, and the like, and the sulfonates include octylbenzene sulfonic acid Na, undecylnaphthalene sulfonic acid N, and the like.
a, Na-di- (2-ethylhexyl) sulfosuccinate and the like, and examples of the phosphate salt include propyl ether phosphate K, octyl phosphate Na and dodecyl phosphate Na.

Nonionic surfactants are specifically glycerin fatty acid ester, sorbitan fatty acid ester, propylene glycol fatty acid ester, sucrose fatty acid ester, mono-, di- and tristearyl citrate, pentaerythritol fatty acid ester, trimethylolpropane fatty acid Ester, polyglycerin fatty acid ester, polyoxyethylene glycerin fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyethylene glycol fatty acid ester, polypropylene glycol fatty acid ester, polyoxyethylene fatty acid alcohol ether, polyoxyethylene alkyl phenyl ether, N, N bis ( 2-hydroxyethyl) fatty acid amine, condensation product of fatty acid and diethanolamine, polyoxypropylene poly Carboxymethyl ethylene block polymers, polyethylene glycol, polypropylene glycol, polyethylene oxide, ethylene oxide adducts of castor oil, et al. And isopropyl alcohol and the like, can be used at least these one or more. Particularly, polyethylene glycol is preferred.

The ratio of the anionic surfactant to the nonionic surfactant in the antifogging agent of the present invention is such that the amount of the anionic surfactant is 1
0 to 99.5% by mass, and 90 to 0.5% of the nonionic surfactant.
5% by mass. Preferably 30 anionic surfactants
９９99.5% by mass, nonionic surfactant is 70０．５0.5%
% By mass, more preferably 5% by weight of the anionic surfactant.
0 to 99.5% by mass, and 50 to 0.5% of the nonionic surfactant.
5% by weight, most preferably 70 to 99.5% by weight of an anionic surfactant and 30 to 9% by weight of a nonionic surfactant.
0.5% by mass. 10% by mass of anionic surfactant
When the ratio is smaller, the nonionic surfactant is larger than 90% by mass, or when the anionic surfactant is larger than 99.5% by mass and the nonionic surfactant is smaller than 0.5% by mass, the prevention by a synergistic effect is achieved. No improvement in haze.

When the surface of the rubber-modified styrenic resin sheet is treated with an antifogging agent, a solution in which an anionic surfactant and a nonionic surfactant are dissolved in a solvent is used. As the solvent, water, alcohol, or the like is used, but the solvent is not particularly limited thereto. Water is preferred for handling. In addition, both anionic surfactants and nonionic surfactants are easily dissolved in water and have excellent handling properties. When used as an anti-fogging treatment solution, the solution concentrations of the anionic surfactant and the nonionic surfactant are not particularly limited, but may be set to 0.1.
It is preferably from 0.01 to 10% by mass.

The rubber-modified styrene resin sheet used in the antifogging rubber-modified styrene resin sheet of the present invention is a sheet before being treated with an antifogging agent obtained by molding a rubber-modified styrene resin. The rubber-modified styrene resin includes a copolymer obtained by polymerizing a styrene monomer and / or a monomer copolymerizable with the styrene monomer in the presence of a butadiene rubber, and a mixture thereof. Can be

The styrene monomer used in the above (co) polymer includes styrene, α-methylstyrene, vinyltoluene, t-butylstyrene and the like, and is copolymerizable with the styrene monomer. Examples of suitable monomers are acrylic acid, ethyl acrylate, methyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, acrylonitrile, methacrylic acid, ethyl methacrylate, methyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, 1,3-butadiene, 2-methyl-1,3
-Butadiene (isoprene) and the like.

The butadiene rubber includes high cis polybutadiene, low cis polybutadiene, styrene-butadiene rubber, styrene-butadiene block rubber, styrene-butadiene-styrene block rubber, partially hydrogenated polybutadiene rubber, and the like. In addition, at least one kind of a monomer and a butadiene rubber used for the polymerization can be used. These rubber-modified styrene resins include high cis polybutadiene, low cis polybutadiene,
Impact-resistant polystyrene (HIPS) obtained by polymerizing styrene in the presence of at least one of styrene-butadiene rubber and styrene-butadiene block rubber is preferred.

The rubber content and the rubber particle diameter in the rubber-modified styrene resin and the rubber-modified styrene resin sheet are not particularly limited, but are more preferably within the range not impairing the transparency. When transparency is important, the rubber content is preferably 0.01 to 10% by mass, and more preferably 0.1 to 5% by mass. Rubber content is 0.
If the amount is less than 01% by mass, the toughness tends to be inferior.
If it is more than 0% by mass, transparency tends to be poor. The rubber particle diameter is preferably 0.01 to 10 μm, and more preferably 0.1 to 5 μm. If the rubber particle diameter is smaller than 0.01 μm, the toughness tends to be inferior, and if it is larger than 10 μm, the transparency tends to be inferior.

The method of processing the rubber-modified styrenic resin into a sheet is not particularly limited, and a common method such as a uniaxial stretching method, a biaxial stretching method, a multiaxial stretching method, a coextrusion method, a laminating method and the like can be mentioned. Can be Further, in order to perform the antifogging treatment on the sheet, it is preferable that the surface of the sheet is modified by a corona discharge treatment method, an ozone treatment method, a plasma treatment method or the like.

The method for treating the antifogging agent treatment liquid into a rubber-modified styrene resin sheet is not particularly limited, and a simple method of applying the solution using a roll coater, a knife coater, a gravure roll coater, or the like is exemplified. . Also,
Spraying, immersion, etc. can also be adopted.

The solid content of the antifogging agent on the surface of the rubber-modified styrenic resin sheet of the present invention treated with the antifogging agent is 0.005 to 0.5.
5 g / m ² is preferred. Solids of rubber-modified styrenic resin sheet anti-fogging agent is hardly appear the effect of antifogging property is less than 0.005 g / m ^2, begins noticeable uneven coating of the sheet surface more than 0.5 g / m ² . The solid content refers to the amounts of components of the anionic surfactant and the nonionic surfactant after removing the solvent of the antifogging agent treatment liquid and drying. For example, when a liquid nonionic surfactant is used, it refers to the amount of antifogging agent applied after drying.

The antifogging rubber-modified styrenic resin sheet of the present invention is a sheet which is used as it is as a packaging material or a coating material for foodstuffs or the like. The thickness of the rubber-modified styrene resin sheet is not particularly limited, and is generally 100 μm to 10 mm. This sheet is molded and used for a container. When importance is placed on the transparency of the antifogging rubber-modified styrene resin sheet, the transparency of the rubber-modified styrene resin sheet is preferably Haz.
e is 20 or less, and more preferably, Haze is 10 or less.

The molded article of the present invention is a lid container or a food pack for packaging a food product or the like formed by pressure-forming, vacuum-forming, vacuum-pressure-forming or the like of an antifogging rubber-modified styrene resin sheet.

[0023]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.
In addition, the physical property measurement in an Example was implemented as follows. (1) Workability: When preparing 99 g of water at a temperature of 25 ° C. in a 200 cc beaker, adding an anti-fogging agent while stirring at 200 rpm with a magnetic stirrer having a diameter of 20 mm and stirring at 200 rpm. Was visually evaluated for solubility. A: Dissolved directly. ：: Dissolved within 10 minutes. X: It did not dissolve even after 30 minutes. (2) Rubber content: Measured using a rubber-modified styrene resin sheet as a sample and using 90 MHz H ¹ -NMR manufactured by JEOL Ltd. (3) Rubber particle size: 130 ° C. in a gear oven
The measurement was performed using a photograph taken by a transmission electron microscope manufactured by JEOL Ltd. on the rubber-modified styrene resin sheet that was heat-shrinked for 1 hour. (4) Sheet transparency: Haze of a rubber-modified styrene-based resin sheet coated with an anti-fogging agent was measured using a measuring instrument N manufactured by Nippon Denshoku Industries Co., Ltd.
It measured with DH-1001DP. A: Haze is 10% or less. ：: Haze is more than 10% and not more than 20%. Δ: Haze is larger than 20%. (5) Sheet appearance: The coating unevenness on the surface of the rubber-modified styrene resin sheet coated with the antifogging agent was visually evaluated. ：: coating unevenness is hardly noticeable. Δ: Some coating unevenness is conspicuous. ×: Coating unevenness is conspicuous.

(6) Evaluation of antifogging property: A sheet or lid container coated with the antifogging agent of the present invention was placed on a PSP (polystyrene paper) container filled with water at a temperature of 40 ° C., with the coated surface facing the water side. And left in a refrigerator at a temperature of 5 ° C. for 45 minutes. Thereafter, the sheet and the lid container were visually evaluated for fogging. ：: Almost no fogging is observed. ：: Clouding is partially observed. Δ: About half the haze was observed. ×: Mostly cloudy. □: Cannot be confirmed because the sheet and lid container are opaque. (7) Evaluation of anti-fogging property: (a) A water drop was dropped on the coating surface side of the lid container coated with the anti-fogging agent of the present invention, and the tangent angle between the lid container and the water droplet was measured by Kyowa Interface Science Co., Ltd. Total CA-DT.
It was measured by type A. In addition, (b) the temperature was 5
After being left in a refrigerator at 45 ° C. for 45 minutes, the lid container is dried, a water drop is dropped on the coating surface side of the lid container, and the angle of the tangent between the lid container and the water droplet is measured by a contact angle meter CA- manufactured by Kyowa Interface Science Co., Ltd. D
T. It was measured by type A. (8) Evaluation of antifogging property: cover the PSP container filled with water at a temperature of 40 ° C. with a lid container coated with the antifogging agent of the present invention,
After the SP container is fixed and left in a refrigerator at a temperature of 5 ° C. for 45 minutes, the lid container is reciprocated 15 times at a speed of 20 cm / sec for 10 cm (10 cm above the original position and the position), and a drop of water drops Was counted. The smaller the number of counted water droplets, the better the antifogging property.

(9) Evaluation of toughness: When 20 lid containers with formed ears are stacked, and the operation of trimming the ear portion at a time of 20 times is performed a total of 5 times for 100 lid containers,
The number of cracks generated in the lid container was counted. The smaller the number of occurrence counts of cracks, the better the toughness.

Example 1 As a rubber-modified styrene resin sheet, a biaxially stretched impact-resistant polystyrene sheet having a rubber content of 3.0% by mass, a rubber particle diameter of 0.2 μm, and a sheet thickness of 0.3 mm was used. Also,
As the anti-fog agent, a 30% by mass aqueous solution of cocoalkyl ether sulfate Na was used as an anionic surfactant, and liquid polyethylene glycol was used as a non-ionic surfactant, and the solid content of the anionic surfactant and the non-ionic surfactant were used. 99% by weight of liquid polyethylene glycol and 1%
It was obtained by adjusting to be mass%. Further, this antifogging agent was diluted so as to be a 1.0% by mass aqueous solution to obtain a sheet coated so that the solid content of the antifogging agent on the sheet surface was 0.06 g / m ² . Also, using the sheet, a lid container (170 mm length × 100 mm width × 5
(0 mm height). In addition, Parsoft EK manufactured by NOF Corporation was used for a 30% by mass aqueous solution of cocoalkyl ether sulfate Na, and PEG300 manufactured by NOF Corporation was used for liquid polyethylene glycol. Table 1 shows the rubber content in the rubber-modified styrenic resin sheet in mass% and the rubber particle diameter in μ.
m, the solid content of the anionic surfactant constituting the antifogging agent and the blending ratio of the liquid polyethylene glycol of the nonionic surfactant were expressed in mass%, and the obtained physical properties were also shown.

Example 2 A 30% by mass aqueous solution of cocoalkyl sulfate Na was used as an anionic surfactant and a liquid polyethylene glycol was used as a nonionic surfactant, and the solid content of the anionic surfactant was determined. The nonionic surfactant was obtained by adjusting the liquid polyethylene glycol to 97% by mass and 3% by mass, respectively. Example 1 except that this antifogging agent was used.
The same was done. In addition, coconut alkyl sulfate Na
Persoft SK manufactured by NOF Corporation was used for a 30% by mass aqueous solution of the above. Table 1 shows the rubber content in the rubber-modified styrenic resin sheet in mass%, the rubber particle diameter in μm, the solid content of the anionic surfactant constituting the antifogging agent, and the mixing ratio of the liquid polyethylene glycol of the nonionic surfactant. And the obtained physical properties are also shown.

Example 3 As an antifogging agent, a 30% by mass aqueous solution of cocoalkyl ether sulfate Na and solid lauric acid K were used as anionic surfactants.
It adjusted so that it might be 60 mass% and 60 mass%. Further, liquid polyethylene glycol was used as the nonionic surfactant, and the total solid content of the anionic surfactant and the liquid polyethylene glycol of the nonionic surfactant were adjusted to 90% by mass and 10% by mass, respectively. I got it. The procedure was performed in the same manner as in Example 1 except that this antifogging agent was used. In addition, NON-SALLN-1 manufactured by NOF Corporation was used for lauric acid K. Table 1 shows the rubber content in the rubber-modified styrenic resin sheet in mass%, the rubber particle diameter in μm, the solid content of the anionic surfactant constituting the antifogging agent, and the mixing ratio of the liquid polyethylene glycol of the nonionic surfactant. And the obtained physical properties are also shown.

Example 4 As an antifogging agent, a 30% by mass aqueous solution of coconut alkyl ether sulfate Na was added to an anionic surfactant and di- (2-
An 80% by mass aqueous solution of sodium (ethylhexyl) sulfosuccinate was adjusted to have a solid content of 60% by mass and 40% by mass. Further, liquid polyethylene glycol was used as the nonionic surfactant, and the total solid content of the anionic surfactant and the liquid polyethylene glycol of the nonionic surfactant were adjusted to 90% by mass and 10% by mass, respectively. I got it. The procedure was performed in the same manner as in Example 1 except that this antifogging agent was used. In addition, Lapisol A-80 manufactured by NOF Corporation was used for an 80% by mass aqueous solution of sodium di- (2-ethylhexyl) sulfosuccinate. Table 1 shows the rubber content in the rubber-modified styrenic resin sheet in mass%, the rubber particle diameter in μm, the solid content of the anionic surfactant constituting the antifogging agent, and the mixing ratio of the liquid polyethylene glycol of the nonionic surfactant. The mass%
The obtained physical properties are also shown.

Example 5 A 30% by mass aqueous solution of coconut alkyl ether sulfate Na was used as an anionic surfactant and a liquid polyethylene glycol was used as a nonionic surfactant, and the solid content of the anionic surfactant was used. And 60% by weight of a liquid polyethylene glycol as a nonionic surfactant and 4%, respectively.
It was obtained by adjusting to be 0% by mass. The procedure was performed in the same manner as in Example 1 except that this antifogging agent was used. Table 2 shows the rubber content in the rubber-modified styrenic resin sheet in mass% and the rubber particle diameter in μ.
m, the solid content of the anionic surfactant constituting the antifogging agent and the blending ratio of the liquid polyethylene glycol of the nonionic surfactant were expressed in mass%, and the obtained physical properties were also shown.

Example 6 A 30% by mass aqueous solution of coconut alkyl ether sulfate Na was used as an anionic surfactant and a liquid polyethylene glycol was used as a nonionic surfactant, and the solid content of the anionic surfactant was as follows. And liquid polyethylene glycol as a nonionic surfactant were obtained by adjusting them to be 40% by mass and 60% by mass, respectively. The procedure was performed in the same manner as in Example 1 except that this antifogging agent was used. Table 2 shows the rubber content in the rubber-modified styrenic resin sheet in mass%, the rubber particle diameter in μm, the solid content of the anionic surfactant constituting the antifogging agent, and the mixing ratio of the liquid polyethylene glycol of the nonionic surfactant. And the obtained physical properties are also shown.

Example 7 A 30% by mass aqueous solution of coconut alkyl ether sulfate Na was used as an anionic surfactant and solid polyethylene glycol was used as a nonionic surfactant, and anionic surfactant and nonionic surfactant were used. The surfactants were obtained by adjusting the solid content to 20% by mass and 80% by mass, respectively. The procedure was performed in the same manner as in Example 1 except that this antifogging agent was used. In addition, polyethylene glycol has P
EG-1000 was used. Table 2 shows the rubber content in the rubber-modified styrene resin sheet by mass%, the rubber particle diameter by μm, the solid content of the anti-fogging agent by mass%, and the obtained physical properties.

Example 8 The same procedure as in Example 1 was carried out except that the same antifogging agent as in Example 1 was used, and the solid content of the antifogging agent on the sheet surface was applied so as to be 0.25 g / m ² . . Table 2 shows the rubber content in the rubber-modified styrenic resin sheet in mass%, the rubber particle diameter in μm, the solid content of the anionic surfactant constituting the antifogging agent, and the mixing ratio of the liquid polyethylene glycol of the nonionic surfactant. And the obtained physical properties are also shown.

Example 9 The same anti-fogging agent as in Example 1 was used.
Solid content 0.6g / m ^TwoExcept that it was applied to
Performed in the same manner as in Example 1. Table 3 shows rubber-modified styrenic resins
Rubber content in the sheet is% by mass, rubber particle diameter is μm, antifogging agent
Content and Nonionic Surface Activity of Anionic Surfactants Constituting Water
The mixing ratio of liquid polyethylene glycol
%, And the obtained physical properties are also shown.

Example 10 The same procedure as in Example 1 was carried out except that the same antifogging agent as in Example 1 was used and the amount of the antifogging agent applied on the sheet surface was adjusted to 0.004 g / m ² . . Table 3 shows the rubber content in the rubber-modified styrenic resin sheet in mass%, the rubber particle diameter in μm, the solid content of the anionic surfactant constituting the antifogging agent, and the mixing ratio of the liquid polyethylene glycol of the nonionic surfactant. And the obtained physical properties are also shown.

Example 11 A biaxially stretched impact-resistant polystyrene sheet having a rubber content of 0.1% by mass, a rubber particle diameter of 6.0 μm, and a sheet thickness of 0.3 mm was used as a rubber-modified styrene resin sheet. Performed similarly to 1. Table 3 shows the rubber content in the rubber-modified styrenic resin sheet in mass%, the rubber particle diameter in μm, the solid content of the anionic surfactant constituting the antifogging agent, and the mixing ratio of the liquid polyethylene glycol of the nonionic surfactant. And the obtained physical properties are also shown.

Example 12 A rubber-modified styrene resin sheet having a rubber content of 1.0% by mass, a rubber particle diameter of 12 μm, and a sheet thickness of 0.3 mm was prepared.
The procedure was performed in the same manner as in Example 1 except that an axially stretched impact-resistant polystyrene sheet was used. Table 3 shows the rubber content in the rubber-modified styrenic resin sheet in mass%, the rubber particle diameter in μm, the solid content of the anionic surfactant constituting the antifogging agent, and the mixing ratio of the liquid polyethylene glycol of the nonionic surfactant. The mass%
The obtained physical properties are also shown.

Example 13 As a rubber-modified styrene resin sheet, a rubber content of 1.0% by mass, a rubber particle diameter of 0.08 μm, and a sheet thickness of 0.3 mm
Example 2 was carried out in the same manner as in Example 1 except that the biaxially stretched impact-resistant polystyrene sheet was used. Table 4 shows the rubber content in the rubber-modified styrenic resin sheet in mass%, the rubber particle diameter in μm, the solid content of the anionic surfactant constituting the antifogging agent, and the mixing ratio of the liquid polyethylene glycol of the nonionic surfactant. And the obtained physical properties are also shown.

Example 14 A biaxially stretched impact-resistant polystyrene sheet having a rubber content of 6.0% by mass, a rubber particle diameter of 0.1 μm, and a sheet thickness of 0.3 mm was used as the rubber-modified styrene resin sheet. Performed similarly to 1. Table 4 shows the rubber content in the rubber-modified styrenic resin sheet in mass%, the rubber particle diameter in μm, the solid content of the anionic surfactant constituting the antifogging agent, and the mixing ratio of the liquid polyethylene glycol of the nonionic surfactant. And the obtained physical properties are also shown.

Example 15 A rubber-modified styrene resin sheet having a rubber content of 15% by mass, a rubber particle diameter of 1.0 μm, and a sheet thickness of 0.3 mm was prepared.
The procedure was performed in the same manner as in Example 1 except that an axially stretched impact-resistant polystyrene sheet was used. Table 4 shows the rubber content in the rubber-modified styrenic resin sheet in mass%, the rubber particle diameter in μm, the solid content of the anionic surfactant constituting the antifogging agent, and the mixing ratio of the liquid polyethylene glycol of the nonionic surfactant. The mass%
The obtained physical properties are also shown.

Example 16 As a rubber-modified styrene resin sheet, a rubber content of 0.05 was used.
Mass%, rubber particle diameter 1.0 μm, sheet thickness 0.3 mm
Example 2 was carried out in the same manner as in Example 1 except that the biaxially stretched impact-resistant polystyrene sheet was used. Table 4 shows the rubber content in the rubber-modified styrenic resin sheet in mass%, the rubber particle diameter in μm, the solid content of the anionic surfactant constituting the antifogging agent, and the mixing ratio of the liquid polyethylene glycol of the nonionic surfactant. And the obtained physical properties are also shown.

Example 17 As a rubber-modified styrene resin sheet, a biaxially stretched methyl methacrylate-butadiene-styrene copolymer sheet having a rubber content of 6.0% by mass, a rubber particle diameter of 0.6 μm, and a sheet thickness of 0.3 mm was used. Except having used, it carried out similarly to Example 1.
Table 5 shows the rubber content in the rubber-modified styrenic resin sheet in mass%, the rubber particle diameter in μm, the solid content of the anionic surfactant constituting the antifogging agent and the mixing ratio of the liquid polyethylene glycol of the nonionic surfactant. And the obtained physical properties are also shown.

Example 18 As a rubber-modified styrene resin sheet, impact-resistant polystyrene having a rubber content of 1.0% by mass and a rubber particle diameter of 0.08 μm and rubber having a rubber content of 1.0% by mass and a rubber particle diameter of 2.0 μm were used. The same procedure as in Example 1 was carried out except that the impact polystyrene was mixed at 95% by mass and 5% by mass, and the extruded resin was biaxially stretched. Table 5 shows the rubber content in the rubber-modified styrenic resin sheet in mass%, the rubber particle diameter in μm, the solid content of the anionic surfactant constituting the antifogging agent and the mixing ratio of the liquid polyethylene glycol of the nonionic surfactant. And the obtained physical properties are also shown.

Comparative Example 1 As an antifogging agent, an 80% by mass aqueous solution of sodium di- (2-ethylhexyl) sulfosuccinate was used as an anionic surfactant.
Liquid polyethylene glycol is used as the nonionic surfactant, and the solid content of the anionic surfactant and the liquid polyethylene glycol of the nonionic surfactant are each 50% by mass.
Adjusted to be obtained. The procedure was performed in the same manner as in Example 1 except that the antifogging agent was applied so that the solid content of the antifogging agent on the sheet surface was 0.24 g / m ² . Table 6 shows the rubber content in the rubber-modified styrenic resin sheet in mass%, the rubber particle diameter in μm, the solid content of the anionic surfactant constituting the antifogging agent, and the mixing ratio of the liquid polyethylene glycol of the nonionic surfactant. And the obtained physical properties are also shown. The evaluation of the anti-fogging property was also poor, the contact angle of the anti-fogging property evaluation was large, and the count of the anti-fogging property evaluation was large.

Comparative Example 2 Sucrose fatty acid ester, hydroxyethylcellulose and polyhydric alcohol were each 30 parts by mass,
Parts by weight, 10 parts by weight, 1% by weight with water
The sheet surface was subjected to anti-fogging treatment after dilution. Others were performed similarly to Example 1. The sucrose fatty acid esters include Riken Vitamin's Riquemar A30,
For hydroxyethylcellulose, HEC-SE400 manufactured by Daicel Chemical Industries, Ltd.
Sorbitol was used. Table 6 shows the rubber content in the rubber-modified styrene resin sheet by mass%, the rubber particle diameter by μm, the solid content of the antifogging agent by mass%, and the obtained physical properties. It can be seen that the workability at the time of preparing the antifogging agent treatment solution is poor, the contact angle of the antifogging property evaluation is large, the count of the antifogging property evaluation is many, and the antifogging properties of the sheet and the molded article are poor.

Comparative Example 3 A 30% by mass aqueous solution of coconut alkyl ether sulfate Na was used as an anti-fog agent and a liquid polyethylene glycol was used as a non-ionic surfactant. The surfactants were obtained by adjusting the solid content to 99.8% by mass and 0.2% by mass, respectively. The procedure was performed in the same manner as in Example 1 except that this antifogging agent was used. Table 6 shows the rubber content in the rubber-modified styrenic resin sheet in mass%, the rubber particle diameter in μm, the solid content of the anionic surfactant constituting the antifogging agent, and the mixing ratio of the liquid polyethylene glycol of the nonionic surfactant. And the obtained physical properties are also shown. It can be seen that the contact angle of (b) in the antifogging property evaluation is large, and the count of the antifogging property evaluation is large, and the antifogging property of the molded article is inferior.

Comparative Example 4 A 30% by mass aqueous solution of coconut alkyl ether sulfate Na and solid lauric acid K were used as anionic surfactants and liquid polyethylene glycol was used as a nonionic surfactant. Solid amounts of coconut alkyl ether sulfate Na and lauric acid K as surfactants and liquid polyethylene glycol as nonionic surfactant were adjusted to 5% by mass, 92% by mass, and 3% by mass, respectively. The procedure was performed in the same manner as in Example 1 except that this antifogging agent was used. Table 6 shows the rubber content in the rubber-modified styrenic resin sheet in mass%, the rubber particle diameter in μm, the solid content of the anionic surfactant constituting the antifogging agent, and the mixing ratio of the liquid polyethylene glycol of the nonionic surfactant. In mass%,
The obtained physical properties are also shown. It can be seen that the contact angle in the evaluation of anti-fogging property is large, and the count of the evaluation of anti-fogging property is large, and the anti-fogging properties of the sheet and the molded article are inferior.

COMPARATIVE EXAMPLE 5 A 30% by mass aqueous solution of coconut alkyl ether sulfate Na was used as an anti-fogging agent, and hydroxyethyl cellulose was used as a non-ionic surfactant, and an anionic surfactant and a non-ionic surfactant were used. It was obtained by adjusting the solid content of the agent to be 5% by mass and 95% by mass. The procedure was performed in the same manner as in Example 1 except that this antifogging agent was used. Table 7 shows the rubber content in the rubber-modified styrenic resin sheet in mass%, the rubber particle diameter in μm, the solid content of the anionic surfactant constituting the antifogging agent, and the mixing ratio of the liquid polyethylene glycol of the nonionic surfactant. And the obtained physical properties are also shown. It can be seen that the contact angle of (b) in the antifogging property evaluation is large, and the count of the antifogging property evaluation is large, and the antifogging property of the molded article is inferior.

Comparative Example 6 The same operation as in Example 1 was carried out except that the antifogging agent was not applied. Table 7 shows the rubber content in the rubber-modified styrene resin sheet by mass% and the rubber particle diameter by μm, and also shows the obtained physical properties. The evaluation of the anti-fogging property was also poor, the contact angle of the anti-fogging property evaluation was large, and the count of the anti-fogging property evaluation was large.

Comparative Example 7 The same procedure was performed as in Example 1 except that a biaxially stretched GP polystyrene sheet having a sheet thickness of 0.3 mm was used as the styrene resin sheet. In Table 7, the solid content of the anionic surfactant constituting the antifogging agent and the blending ratio of the liquid polyethylene glycol of the nonionic surfactant are shown by mass%, and the obtained physical properties are also shown. It can be seen that the toughness is poor.

[0051]

[Table 1]

[0052]

[Table 2]

[0053]

[Table 3]

[0054]

[Table 4]

[0055]

[Table 5]

[0056]

[Table 6]

[0057]

[Table 7]

[0058]

The antifogging agent of the present invention is excellent in workability when preparing a solution for treating an antifogging agent, and an antifogging rubber-modified styrene resin sheet using this antifogging agent and a molded article thereof can be used. It is excellent in fogging and toughness, so that it can be widely used for packaging materials and the like. Particularly, those having excellent transparency are very useful for packaging foodstuffs and the like.

Claims (4)

[Claims] 1. An anti-fogging agent comprising a rubber-modified styrene resin sheet containing 10 to 99.5% by mass of an anionic surfactant and 90 to 0.5% by mass of a nonionic surfactant. And 30% by mass in the anionic surfactant in the antifogging agent
An antifogging rubber-modified styrenic resin sheet as described above, which has been surface-treated with an antifogging agent which is a sulfate ester salt. 2. The amount of antifogging agent obtained by subjecting a rubber-modified styrene resin sheet to a surface treatment is 0.005 g to 0.5 g as a solid content.
/ M ² , wherein the antifogging rubber-modified styrenic resin sheet according to claim 1 is used. 3. A rubber-modified styrene resin sheet comprising:
3. The antifogging rubber-modified styrene resin sheet according to claim 1, wherein an axially stretched impact-resistant polystyrene sheet is used. 4. A molded article obtained by using the antifogging rubber-modified styrene resin sheet according to any one of claims 1 to 3.