JPS60250045A - Foam having uneven surface pattern - Google Patents

Abstract

PURPOSE:To provide the titled foam having sharp edges and a deep emboss depth, by simultaneously expanding a two-layer material composed of two PVC resins. CONSTITUTION:A paste PVC resin having an average degree of polymn. of 1,500 or below and contg. a blowing agent, a plasticizer, a stabilizer, etc. is applied to a substrate such as flame-retarded paper or release paper and caused to gel to such an extent that the resin is not expanded, whereby a base layer is formed. A paste PVC resin having an average degree of polymn. higher by at least 200 than that of PVC used for the base layer contg. the blowing agent, the plasticizer, the stabilizer, etc., is applied to the surface of the base layer to form a material having two layers composed of the base layer and an emboss forming layer. The two layers are simultaneously expanded by heating at 180- 300 deg.C. If necessary, the base layer and the emboss forming layer are then peeled off.

Description

DETAILED DESCRIPTION OF THE INVENTION More specifically, the present invention relates to a foam having an extremely sharp uneven surface pattern.

Vinyl chloride resin is widely used in foaming applications such as artificial leather, wallpaper, and flooring materials because it is easy to process. These processed products have embossed surfaces to resemble natural materials, and have aesthetically pleasing patterns, giving them commercial value as interior materials. Embossing methods that increase the added value of the foam used include a mechanical method that presses the embossing pattern immediately after forming the foam, and a special printing method on the foam sheet that suppresses or promotes foaming. Chemical methods are typically used to form irregularities, but various other methods have also been attempted.

However, the embossments obtained with existing embossing processes are shallow, and the embossed edges are not sharp.
Product applications have been limited to wall materials, flooring materials, and artificial leather. In recent years, foam embossing products have been used in a wide range of applications that take advantage of the characteristics of foam, and foams that are thick, have strong surface strength, are deeply embossed, and have sharp edges are desired.

Furthermore, in the existing foam embossing process, in addition to a heating oven for foaming, expensive special equipment for embossing, such as a suppression device and a printing device, are required, which increases the cost of embossing.

The present inventor has created a foam that is thick, has strong surface strength, has sharp edges, and has deep embossing depth, which has been difficult to obtain with conventional techniques, and has the above-mentioned properties without using special equipment for embossing. As a result of intensive study to provide the above, the present invention has been established.

That is, the present invention comprises a base layer (A) made of a vinyl chloride resin having an average degree of polymerization of 1500 or less, and an embossed layer made of a vinyl chloride resin having an average degree of polymerization at least 200 or more higher than the vinyl chloride resin used for the base layer (4). This invention relates to a foam having an uneven surface pattern obtained by simultaneously foaming the two-layered material of layer (B).

Unlike conventional embossed products, the foam of the present invention is a thick foam sheet, has strong surface strength, and has deep embossed patterns and sharp edges. Furthermore, unlike conventional embossing, the foamed [phase] embossed body is processed only by foaming and opening, without using any special equipment for embossing, so the cost is significantly lower than that of conventional embossing. It can be manufactured with The foamed embossed body can be used not only for conventional decorative items such as wall materials, flooring materials, and leather, but also for industrial material applications that were previously considered difficult or impossible, such as thick cushion sheets, soundproofing materials, It can also be used as a heat insulating material.

As the vinyl chloride resin in the present invention, homopolymers and various copolymers polymerized by suspension polymerization, fine suspension polymerization, emulsion polymerization, etc. can be used alone or in combination. Preferably, it is a vinyl chloride paste resin obtained by microsuspension polymerization or emulsion polymerization. The foamed embossed body is characterized by being composed of two layers using vinyl chloride resins having different degrees of polymerization, and the vinyl chloride resin used for the base layer has an average degree of polymerization of 1500 or less, preferably 800 to 1300. The vinyl chloride resin used for embossing and layering should have an average degree of polymerization higher by at least 200 than that of the vinyl chloride resin used for the base layer, preferably from 1500 to 1800. Average degree of polymerization is 200
If the difference is less than 1,000 yen, the foaming behavior of the base layer and the embossed layer will be similar, so the foaming misalignment between the two, which is a characteristic of the embossed formation mechanism, will not occur, making it impossible to obtain an effective embossed pattern. .

In addition to the vinyl chloride resin, the foaming composition used in the present invention contains known plasticizers, 9 foaming agents, and stabilizers.

It may contain fillers, pigments, etc.

As the foaming agent, azodicarbonamide is preferably used; if the foaming rate is too high, it is difficult to obtain a thick foam. However, if the purpose is not to obtain a thick foam, azoisobutylnitrile + F + P'-oxybisbenzenesulfonyl hydrazide or the like can also be used.

Examples of the plasticizer include esters such as phthalic acid, chlorinated paraffins for imparting flame retardancy, and phosphorous esters.

As the foaming agent, a commercially available liquid stabilizer is used, but low zinc oxide or the like may also be used.

As the filler, heavy charcoal-based calcium, hydrated aluminum, clay, etc. are used.

The proportion of various additives added to the vinyl chloride resin varies depending on the type of additive and is usually not limited in any way. For example, when a sodium zinc stabilizer is used, for 100 parts by weight of vinyl chloride paste resin,
It is preferable to use 3 to 10 parts by weight of a blowing agent, 50 to 80 parts by weight of a plasticizer, and 2 to 4 parts by weight of a stabilizer.

The foamed embossed body is produced by first applying the foamed sol of the base layer (A) onto a base material such as flame retardant paper or release paper using a coating material, gelling it to a state that does not lead to foaming, and then applying the embossed sol to the embossed layer (B). ) is applied to form a two-layered material of (A) and (B), and the layered material is simultaneously foamed in a foaming oven.

Foaming is performed at 180-300℃ using a normal foaming opener.
It is carried out by heating.

If the temperature is lower than 180°C or higher than 300°C, a good embossing cannot be obtained. The heating time varies depending on the type of heating device. If the heating time is too short, good embossing cannot be obtained even if the heating temperature is appropriate.

Furthermore, in the present invention, by selecting the blending composition and foaming conditions of the base layer and the emboss-forming layer, it is possible to change the pattern or to enable delamination between the base layer and the emboss-forming layer.

The sheet obtained by peeling maintains the embossed pattern and provides a skin-free, highly open-celled foam sheet.

The present invention will be explained in more detail below using examples. Example-1 The A-1 composition sol shown in Table-1 was used for the base layer, and was coated on a release paper to a thickness of (L5 sam), cured to the gelation stage, and rolled up. -1 composition sol was coated with a thickness of 11 m for the embossed layer, foamed at an open temperature of 200° C. for a residence time of 1 min, and rolled up after cooling.

In this way, it was possible to obtain a highly elastic foamed sheet shown in FIG. 2 having a thickness of 5 mm and having extremely voluminous irregularities.

Comparative Example-1 Mu1 composition sol was baked in the same manner as in Example-1, and 0 composition sol was applied on top of it on the base layer, and foamed at 200°C for a residence time of 1 minute, but the surface unevenness was not obtained at all.

Example 2 A-1 composition sol was first coated on a release paper to form a base layer with a thickness of 13 mm, then burned and rolled up. Next, the B-2 composition sol was coated on the base layer to a thickness of cL1BsI and foamed in an oven at 200°C for a residence time of 50 seconds to form a sol of 2.5 cm with a different pattern and shallower unevenness than in Example-1. A foamed sheet was obtained.

Comparative Example-2 A-1 composition sol was coated with a coating diameter of α5 in the same manner as in Example-1, and B-2 composition sol was coated on top of it with a coating diameter of [11 m].
It was coated thickly and foamed at an oven temperature of 200° C. and a residence time of 1 minute. The obtained sheet was a simply foamed sheet with neither regularity nor volume.

Example-3 A-2 composition sol was coated on a flame-proof paper (with a thickness of 15 sm) as a base layer, and after coating, B-5 composition sol was coated with α1
It was coated on the base layer to a thickness of (1) and foamed in an oven at 200° C. for a residence time of 1 minute. After cooling, the embossed layer was peeled off to form the embossed layer shown in FIG. It's a difference.

Furthermore, the pattern and volume (depth) can be changed by changing the coating thickness, the type of compounding agents, and the foaming conditions.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of the apparatus used to carry out the invention. 1..., Tooter 2... Heating open S... Rolling device 4... Cooling roll 5... Winding device FIG. 2 is a cross-sectional view of the foam obtained in Example 1. . FIG. 3 is a cross-sectional view of the embossed sheet obtained in Example 3. FIG. 4 is a sectional view of a sheet suitable as a wall covering material obtained in Example 3. Patent applicant: Toyo Soda Kogyo Co., Ltd. Figure 1 Figure 3 Figure 4

Claims (1)

[Claims] 1. A base layer (4) made of a vinyl chloride resin with an average degree of polymerization of 1500 or less, and an emboss forming layer (B ) A foam having an uneven surface pattern obtained by simultaneously foaming a two-layered material.