JPS6218440Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a flocked foam that has a pattern of unevenness with large steps created by high-frequency welder embossing. Concerning endless flocked foam.

In recent years, suede-like artificial leather that imitates the backskin of natural leather, or flocked materials that resemble the texture and appearance of such artificial leather, have been used for a variety of purposes, such as for furniture, furniture, and wall coverings. As a type of flocked material, synthetic fibers such as rayon or nylon are flocked to a soft foam base material such as plastic or rubber. Various soft flocked foams have been developed that combine flexibility and pile feel to give a good feel. However, endless rubber foams that can serve as good base materials for flocking are not available on the market, except for foams of 1,2-polybutadiene resin or polymer blends containing this as one component, which will be described later. Almost invisible. The base material is an endless foam, and the property that it can be directly flocked to the surface makes it suitable for applications that require long lengths such as various interior materials such as carpets, wall materials, and ceiling materials. Needless to say, such a long flocked foam is economically advantageous in that it has a good yield even for applications that require cutting, such as miscellaneous goods. .

Although soft polyvinyl chloride and soft polyurethane foams are soft foams that can be flocked, they have the following drawbacks as a flocking base material.

That is, a paste-like soft polyvinyl chloride foam containing plasticity has a low heat resistance temperature of about 70°C, and during flocking, it softens and fuses at the stage of thermosetting the pile adhesive. Therefore, the method of selecting adhesives and lowering the baking temperature (e.g. 125℃)
(for 10 minutes), but it is difficult to obtain products with good frictional strength using this method. In addition, although it is possible to form a concave-convex pattern with relatively large steps by flocking the soft polyvinyl chloride foam base material,
As the plasticizer oozes out from the foam base material, problems such as reduced pile adhesion, toxicity, and hardening at low temperatures occur, and in particular, due to the reduced pile adhesion, a large amount of pile falls off during embossing. In addition, the pile peels off from the foam at the edges of the uneven pattern, resulting in inferior products with no commercial value.

In addition, since flexible polyurethane foam is generally an open-cell foam made of resin with a three-dimensional structure,
Embossing can only be done at relatively high temperatures and pressures, and since the foam is an open foam with no skin layer on its surface, the binder of the flock is only the cell walls, making it difficult to obtain flocked materials with good abrasion fastness. do not have.

On the other hand, the foamed material of the 1,2-polyptadiene resin used in the present invention or the polymer blend containing the same as one component does not have the above-mentioned drawbacks, and has excellent flexibility, stretchability, drapability, elasticity, and It has excellent properties such as heat retention, and its flocked body has an extremely good texture that gives the human body a rich tactile sensation and a feeling of pressure.

By the way, there are two ways to obtain an embossed body: one is to use a heated roll or hot press, and the other is to use a high-frequency welder. The high-frequency welder embossing method is extremely superior in that it can clearly emboss fine patterns in a short time at low temperatures. This is the method. However, the aforementioned rayon pile and nylon pile, which are commonly used as piles for flocking, are materials that cannot be subjected to high-frequency welder embossing because the former is non-fusible and the latter has a high melting point. Of the above-mentioned soft foams, the only one that can be embossed using a high-frequency welder is soft polyvinyl chloride foam (however, as mentioned above, foams with flocking are inferior products and have not been put to practical use). However, it is difficult to emboss the 1,2-polybutadiene resin or a polymer blend containing the same as one component, and the flexible polyurethane foam used in the present invention by high-frequency welder embossing. Therefore, those skilled in the art understand that flocked bodies based on 1,2-polybutadiene resin, which is difficult to emboss with high-frequency welders, or foams of polymer blends containing 1,2-polybutadiene resin as one component, cannot be embossed with high-frequency welders. It was thought that it would be impossible to create an uneven pattern with large steps that reach the inside thickness of the foam base material by the embossing method.

However, as the inventors conducted various research, they realized that embossing was previously thought to be difficult.
2-For flocked foams in which specific piles called modacrylic fibers are flocked to the foam base material of polybutadiene resin or a polymer blend containing polybutadiene resin as one component, this can be done using a high-frequency welder. By embossing it, we discovered the surprising fact that in just a few seconds, it is possible to form a clear concave-convex pattern with two-tone tones, rich in three-dimensionality, and large steps.This led us to complete the invention. .

Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic perspective view showing one embodiment of the flocked foam of the present invention, and FIG. 2 is a schematic enlarged sectional view taken along the line 1-- in FIG. It is a pile.

The foam constituting the base material 1 is a foam obtained from a 1,2-polybutadiene resin or a polymer blend containing this as one component. There are various types of 1,2-polybutadiene resins, ranging from liquid types with low molecular weights to highly crystalline types with no processability. is over 100,000, crystallinity is 10-50%,
Low-crystalline, high-molecular-weight 1,2-polybutadiene resin with syndiotactic stereoregularity of 20% or more and good thermal stability, moldability, and photosensitivity (for example, a product manufactured by Nippon Gosei Rubber Co., Ltd.) name, JSR, RB−810
etc.) are preferably adopted. The polymer blended with this 1,2-polybutadiene resin is
For example, vinyl acetate-olefins, vinyl alcohol-based materials that are compatible and have relatively similar softening points.
Among vinyl copolymers such as olefin type and acrylic acid ester-olefin type, those containing about 10 mol % or more of a polar component such as vinyl acetate are preferably used. By blending such polar polymers, a foam with good embossing properties by high-frequency welding can be obtained, and the embossing process time can be shortened. Of these, vinyl acetate-olefin systems, especially vinyl acetate-ethylene copolymers, are the most desirable, and when blended with these copolymers, foams with very good texture and embossing properties by high-frequency welder embossing are produced. can get. The blending ratio of the polymer to the above-mentioned 1,2-polybutadiene resin is 3:7 to 7 by weight.
A range of 7:3 is preferable. If the amount of the polar polymer is too small, the embossing properties of the resulting foam obtained by high-frequency welder embossing will not be improved much, whereas if it is too large, the foam will have a poor texture and become sticky. In some cases, it may also be possible to further blend a polymer other than the above-mentioned polar polymer to adjust the texture, etc. of the resulting foam. Polymers for controlling such texture include:
Polyolefins such as polyethylene, polypropylene, polybutene, etc., which are compatible and have relatively similar softening points, are preferably used, and these may be blended in an appropriate amount.

The foam base material in the present invention includes the following 1,
A 2-polybutadiene resin or a polymer blend containing the same as one component is foamed by a conventional foam manufacturing method, and the 1,2-polybutadiene resin is photosensitive to ultraviolet rays. Therefore, it is advantageous to crosslink the resin using an ultraviolet crosslinking method and foam it using a blowing agent decomposition method as follows.

That is, a photosensitizer, a blowing agent,
Anti-aging agents, colorants, etc. are added as necessary, and this is continuously extruded into a thin endless sheet using an extruder, and 1,2- This is a method in which polybutadiene resin is pre-crosslinked and then heated to a temperature higher than the decomposition temperature of the blowing agent to cause foaming and expansion. The foam thus obtained is determined by the amount of foaming agent added, the amount of photosensitizer added,
By adjusting the amount of ultraviolet ray irradiation and other foaming conditions, the foaming ratio and texture can be adjusted.

On the other hand, the pile used in this invention is made of modacrylic fiber made from a long-chain polymer containing 35 to 85% acrylonitrile, and it is better to use fiber that is highly polar and has a low softening point for embossing. easy. A typical example is a flame-retardant fiber made of a long-chain polymer consisting of 35-85% acrylonitrile and 65-15% vinyl chloride, both of which have polar components. Because it generates a lot of heat and has a low softening point of around 150°C, when embossing is performed using a high-frequency welder, the pile of the part of the welder pressed against the adapter or the convex part of the mold (i.e., the concave part of the concave-convex pattern) will disappear in a few seconds. It will eventually soften and melt and fall sideways. This modacrylic fiber pile is
From the perspective of improving the feel of the flocked foam, it is ideal to use as long and thin pile as possible, but in reality it is difficult to obtain long and thin piles, so in this invention we The length is 1.2~1.3mm
We use piles with a denier thickness of 1.5 to 3.0 mm. When using piles of this size, they match well with the flexibility and cushioning properties of the sheet base material, giving the feeling of using piles that are much longer than the actual pile, and making it easier to use piles that are longer and thicker than the actual pile. , or a better texture than using short and thin ones.

There are no restrictions on the method of flocking such piles, and any conventionally known method may be used. For example, a flocking adhesive such as a reactive polyacrylic acid ester emulsion that has good adhesion to foam substrates can be used with a doctor knife or the like to make a dry weight of approximately 50%
A coating amount of ~200 g/m ² is applied to the surface of the foam base material, the pile is electrostatically flocked using the up method under a high voltage of approximately 30,000 volts or more, and pre-dried for several minutes at approximately 80 to 110°C. After that, it is baked at about 120 to 140°C for about 2 to 10 minutes.

The flocked foam with a textured pattern of the present invention is an endless flocked foam material in which piles made of modacrylic fibers as described above are flocked to a foam base material of the above-mentioned 1,2-polybutadiene resin or a polymer blend containing the same as one component. The flocked foam is intermittently supplied to a high-frequency welder having an adapter engraved with a desired uneven pattern, and the adapter is pressed onto the flocked layer to emboss it and form the desired uneven pattern. It is engraved on the surface of the foam. Since the modacrylic fiber pile contains polar components, it is internally heated in a very short time to reach the temperature required for embossing. Therefore,
The time required for embossing is generally about several seconds, and about several tens of seconds at most. The number of waves used may be 27.12MHz, 40.46MHz, or 41.14MHz as approved by the Radio Control Act, and the output may be selected from the range of 1 to 100 kW depending on the area of the desired concave and convex pattern. Note that in some cases, such as when the sheet is thick, it may be preferable to preheat the sheet before embossing.

The flocked foam with a concavo-convex pattern illustrated in FIG. As schematically shown in Fig. 2, the piles 21 of the concave portion 3 that are pressed into contact with the adapter are half-welded or welded to each other and lie sideways, and the piles 22 of the convex portion 4 that are not in contact with the adapter are It is in a standing state with the hair transplanted. Therefore, in this flocked foam, the concave portions 3 where the pile lies are dark colored, and the convex portions 4 where the pile stands are light colored, and the uneven pattern has two shades of dark and light, giving it a beautiful suede-like depth. Become something.
This type of uneven pattern with two colors of light and shade is
Conventional non-fusible piles such as rayon and cotton
Alternatively, when a pile such as conventional nylon, which is difficult to melt under normal embossing conditions, is used, it is difficult to form the pile. In addition, in the foam base material 11 of the concave portion 3 of this flocked foam, the cell membrane is welded and the cells are collapsed to some extent, but a considerable number of cells that have been compressed and deformed without being crushed remain. ing. Therefore, the foam base material 11 of this recess 3
Although the foam base material 12 of the convex portion 4 has a lower foaming rate, it still has good flexibility, elasticity, cushioning properties, etc., and can maintain a good feel. . This good texture is also due to the pile having a length of 1.2 mm, which best matches the foam base material.
As mentioned above, this is also due to the use of Modacrylic fiber pile with a thickness of ~1.3 mm and a thickness of about 1.5 to 3.0 denier.

Furthermore, in the flocked foam of the present invention, it is a fact that a concavo-convex pattern with a rich three-dimensional effect is engraved with large steps extending into the thickness of the foam base material 11 as shown in the figure. As mentioned in the prior art section, 1.
2-Polybutadiene resin foam can be embossed using a heated roll or heated press, but embossing with a high-frequency welder is generally not easy, and even if embossed with a high-frequency welder under high pressure, only very shallow irregularities will be produced. Not formed. Incidentally, we conducted an experiment in which embossing was carried out in the same manner as the flocked foam of the present invention, using the foam base material of the foam used in the present invention alone or with conventional rayon pile and nylon pile flocked thereon. However, in both cases, only extremely shallow uneven patterns were engraved, and it was not possible to obtain the deep uneven patterns as in the flocked foam of the present invention.The piles were uniformly erected, and a single color tone was extremely indistinct. It became an uneven pattern. In view of the experimental results, it is possible to engrave a pattern with a large difference in unevenness on the flocked foam of the present invention because:
When a flocked foam in which a specific pile of modacrylic fibers is flocked to a specific base material made of a foam of 1,2-polybutadiene resin or a polymer blend containing this as one component is subjected to high-frequency welder embossing. Only. Although the mechanism of action is unclear, the foam base material 11, which does not have a high melting point or modulus, is easily deformed under heat and pressure during embossing, resulting in the pile 21 of the recessed portion 3 being semi-welded or welded.
It is assumed that this is because the adhesive layer 5 is quickly cooled and solidified before the foam base material 11 in the recesses is restored, thereby preventing the low modulus foam base material 11, which does not have a very large restoring force, from restoring. do. It goes without saying that when deep unevenness is formed in this manner, and the concave portions 3 and convex portions 4 have two shades of color, as described above, the synergistic effect results in a clear uneven pattern with an extremely three-dimensional effect. Nor. Incidentally, when modacrylic fibers are flocked onto paper or fabric and high-frequency embossed, the pressed areas of the recesses become hard and lose the texture of the pile, and the depth of the embossing is much greater than that of the present invention. It is shallow and lacks three-dimensionality.

In addition, foam base material 1 used for the flocked foam of the present invention
is a foam with extremely dense cells on the surface and a skin layer, so as shown in FIG. It is a uniform thin layer. Therefore, it is economical because it is only necessary to apply the minimum amount of adhesive 5, and the piles 2 can be bonded evenly and firmly. Moreover, the foam base material 11
It has extremely high peeling resistance. Therefore, inconveniences such as uneven flocking, falling of the pile during embossing, and peeling of the adhesive from the foam base material hardly occur.

As described above, the present invention uses specific materials for the foam and pile as the base material, and embosses them with a high-frequency welder to create a suede with a rich three-dimensional effect with two shades of light and shade. This is the first time that we have been able to provide an endless flocked foam with a textured texture that has a clear texture pattern and a good feel, and can be manufactured industrially with great efficiency, so it is extremely significant. In particular, modacrylic fibers made of vinyl chloride-acrylonitrile copolymers are flame retardant and are suitable for use in building materials such as wall covering materials, flooring materials, ceiling materials, furniture, and clothing.

The term "uneven pattern" as used herein does not mean only a simple geometric or amorphous pattern, but is a concept that broadly includes shapes, designs, characters, symbols, etc. It goes without saying that the flocked foam of the present invention is not limited to the one shown in the illustration, but may be modified in various ways without departing from the gist of the present invention, such as by being lined with an appropriate base fabric, etc. Nor.

[Brief explanation of the drawing]

FIG. 1 is a schematic perspective view showing an embodiment of the flocked foam with an uneven pattern according to the present invention, and FIG. 2 is a schematic enlarged sectional view taken along the line of FIG. 1. Explanation of the symbols: 1... Foam base material, 2... Pile, 3... Concave portion, 4... Convex portion, 5... Adhesive.

Claims (1)

[Scope of utility model registration request] A foamed base material made of 1,2-polybutadiene resin or a polymer blend containing this as one component is flocked with piles made of modacrylic fibers, and is embossed with a high-frequency welder to form a layer within the thickness of the base material on the surface. Flocked foam with an uneven pattern with large steps.