JPH0333465Y2 - - Google Patents

Description

[Detailed explanation of the idea]

<Industrial Application Field> The present invention relates to a molded product having a foam layer, and more specifically, it is a molded product with cushioning properties, non-slip properties, and a soft texture suitable for use as a packaging container tray, partition, and display material. The present invention relates to a molded article having the following properties. <Prior art> Foamed materials have been widely used as packaging containers in the past, and sheets or molded containers have been made by heating and melting resin in which a foaming agent is dispersed and extrusion molding. It was difficult to obtain a comfortable texture, and it was also difficult to partially provide a foam layer. The method of applying foaming ink, forming a foamable resin layer, and then heating and foaming is a simple method, and any pattern can be formed, and the base material can be freely selected from plastic, paper, cloth, metal, etc. It is also widely used as a packaging material due to its features such as a soft texture that cannot be obtained with extrusion molding. The application of foamed ink to foamed molded products includes foamable sheets made by applying foamable ink to a heat-deformable base material that simultaneously performs molding and foaming by utilizing the heat required during molding such as compressed air or vacuum forming. For example, Japanese Patent Publication No. 54-16763, Utility Model Application Publication No. 57-98823).
The resulting foam layer has non-slip properties, appropriate cushioning properties, and heat insulation properties, and the surface has a soft texture similar to that of flocked hair. However, the surface resistance is generally low, and there have been problems with the foam layer being scratched or falling off due to abrasion caused by the contents during handling or when used as a container. Another problem was that the non-slip properties were too high, making it difficult to remove molded products when they were stacked, resulting in poor workability. <Problems to be solved by the invention> The present invention improves abrasion resistance without impairing the soft texture of the surface of the foam layer of a foam molded article using the foamable ink, and also provides appropriate slip resistance. The object of the present invention is to provide a foamed molded article that has been adjusted to improve workability. <Means for Solving the Problems> The present invention was obtained as a result of studies to solve the above-mentioned problems. That is, the present invention provides a molded article obtained by thermoforming a foamable laminate sheet consisting of a thermoformable plastic sheet and a foamable ink composition layer, and foaming the foamed ink composition layer. A packaging material with excellent surface resistance can be obtained by applying a varnish made of a thermoplastic resin with a softening point of 100°C or less to the surface and drying it to form a protective coating layer with a thickness of 1 to 15 μm. This is what we discovered. The present invention will be explained in more detail below using the drawings. FIG. 1 is a sectional view schematically showing the structure of a foamable sheet according to the present invention. 1 represents a thermoformable plastic sheet, 2 represents a foamable ink composition layer, and 3 represents a protective coating layer. As the thermoformable plastic sheet 1, plastics such as vinyl chloride, polystyrene, acrylic resin, polycarbonate, etc. can be used. The foamable ink composition layer 2 is made by fully or partially forming a suitable resin layer from foamable resin layers having a foaming temperature of 100°C to 200°C and a foaming ratio of 5 to 20 times to a thickness of 10 μm to 200 μm. Foaming ink is a layer formed by coating on polyvinyl chloride, polystyrene,
Thermoplastic resins such as acrylic esters, azobis-formamide, azobisisobutyronitrile, dinitrosopentamethylenetetramine, P-
It is dissolved and dispersed in a solvent with the addition of an organic blowing agent such as P′oxybis, or microcapsules filled with a liquid that gasifies when heated.
Any composition is determined depending on the adhesion to the base material, processability, foamability, etc. Methods for forming the foamable ink composition layer 2 on the thermoformable plastic sheet 1 include gravure printing, silk screen printing, roll coating, etc., and it can be formed on the entire surface or in any desired shape such as a pattern, letters, or pattern. It is possible. The protective coating layer 3 is a thermoplastic resin such as polyester, vinyl chloride-vinyl acetate copolymer, acrylic resin, polyamide, polystyrene, polyvinyl acetate, polyvinyl alcohol, rubber resin, etc., and is made into a varnish with an appropriate solvent. was selected in consideration of its adhesion to the foamable ink composition layer 2, which is the underlying layer, and was coated and dried in the same manner as the foamable ink composition layer 2. The above-mentioned thermoplastic resin melts during molding and has fluidity, and a resin having a softening temperature lower than the foaming temperature of the foamable ink composition layer 2 having a softening point of 100° C. or lower is preferable. Furthermore, if the protective coating layer 3 is too thick, the soft texture will be lost. Although it varies depending on the type of resin, as a result of examining the balance with the effect on surface resistance, it was found that the effect of the present invention can be obtained with a thickness of 1 μm to 15 μm. Furthermore, by adding a lubricating substance such as wax, fatty acid amide, silicone, or fluorine to the above-mentioned varnish, it was also possible to adjust the non-slip property of the surface of the resulting foamed molded product. FIG. 2 shows a sectional view of the foam molded article of the present invention which has been heated and foamed. The foamable ink composition layer 2 forms a foamed resin layer 4 by heat during molding, and the protective coating layer 3 melts and follows the foaming of the foamed resin layer 4 to cover the surface and improve surface resistance. shall be. <Example> Next, the present invention will be described with reference to an example. Example 1 On one side of a hard vinyl chloride sheet with a thickness of 0.3 m/m, a blowing agent containing a volatile liquid that gasifies by heating is sealed in microcapsules of polyvinylidene chloride resin in an acrylic acid ester resin binder. A foaming ink composition prepared by adding the above emulsion is applied by a roll coating method, dried,
After obtaining a foamable ink composition layer with a thickness of 70 μm, a varnish made of an acrylic ester resin with a softening temperature of 95° C. was applied to the surface of the foamed ink composition layer using a gravure coating method, dried, and a layer with a thickness of 5 μm was obtained. After obtaining a laminated sheet provided with a protective coating layer, a tray-shaped foamed product was obtained using a vacuum forming machine at a forming temperature of 150°C and a drawing ratio of 0.3. Example 2 As a varnish made of the acrylic acid ester resin of Example 1, polyethylene wax was used in terms of resin ratio.
A foamed molded article was obtained in the same manner as in Example 1 except that a varnish containing 100:0.5 was used. Comparative Example A sheet consisting of a hard vinyl chloride sheet and a foamable ink composition layer obtained in the same manner as in Example 1 was used in a vacuum forming machine at a forming temperature of 150°C to obtain a tray-shaped foam molded product with a drawing ratio of 0.3. Ta. The evaluation results of Examples 1, 2 and comparative examples are shown in Table-1.

[Table] In both Examples 1 and 2, excellent wear resistance was obtained as shown in Table 1 while maintaining a soft surface texture comparable to that of the conventional foam molded product obtained in the comparative example. Furthermore, as shown in Example 2, the coefficient of static friction was reduced, the slip property could be adjusted, and the handling efficiency was improved. <Effects of the invention> The foamed molded article according to the invention is characterized in that a protective coating layer made of a thermoplastic resin having a low softening point lower than the foaming temperature of the foamed ink composition layer is formed by coating. The strength and contamination resistance of the foam layer surface can be improved without impairing the soft texture of the surface created by the foam ink.Furthermore, the slipperiness can be adjusted to an appropriate level, making it easier to pull out when stacking molded products, etc. This significantly improves work efficiency.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, FIG. 1 shows a cross-sectional view of the foamable sheet of the present invention before molding, and FIG. 2 shows a cross-sectional view of the foam molded product of the present invention heated and foamed by molding. . DESCRIPTION OF SYMBOLS 1... Thermoformable plastic sheet, 2... Foamable ink composition layer, 3... Protective coating layer, 4...
Foamed resin layer.

Claims (1)

[Claims for Utility Model Registration] 1. In a molded article obtained by thermoforming a foamable laminate sheet consisting of a thermoformable plastic sheet and a foamable ink composition layer, and foaming the foamed ink composition layer, 1 to 1, which is obtained by coating and drying a varnish made of a thermoplastic resin having a softening point of 100°C or less on the surface of an ink composition layer.
A foam molded product characterized by having a 15μ thick protective coating layer. 2 The varnish made of thermoplastic resin is silicone,
A foamed molded article according to claim 1, which is a utility model registration, and is made of a varnish to which a lubricating substance of fatty acid amide and polyethylene WAX is added.