JP2938008B1 - Method for producing artificial marble having a stripe pattern - Google Patents

Abstract

Abstract: PROBLEM TO BE SOLVED: To provide a method for producing an artificial marble capable of forming a stripe pattern which is continuously formed also in a thickness direction, does not disappear even when the surface is cut, and changes in a nearly natural manner in a simple manner. Offer. SOLUTION: At least two layers of liquid resins of different colors are laminated in a molding cell. Next, a comb-shaped tool is moved in the liquid resin while its teeth are in contact with the bottom surface of the molding cell and the distance between the teeth is changed. Thereafter, the liquid resin is cured to obtain an artificial marble with a stripe pattern.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing artificial marble having a stripe pattern.

[0002]

2. Description of the Related Art Conventionally, artificial marble used for a counter of a wash basin, a table top, and the like has been manufactured by curing a liquid resin. As a method of manufacturing such artificial marble having a pattern on the surface, a method of mixing a synthetic resin material of a different color when injecting a liquid resin into a molding cell is disclosed in Japanese Patent Publication No. 59-1568 and Japanese Patent Publication No. 59-1568. Kaihei 1-
This is known from US Pat.

However, these conventional methods have a problem that the reproducibility of the appearance of the pattern is lacking and the product yield for obtaining a good product is low. In addition, when used as artificial marble, the surface is often cut,
At that time, it is necessary to maintain the pattern on the surface, but when cutting, the pattern often disappears or changes significantly. Furthermore, when a different material is used for the appearance of the pattern, there is a difference in the curing speed or a difference in the physical properties between the materials is likely to occur. Mechanical performance was sometimes reduced.

[0004]

As a method for solving the above-mentioned problems, the present inventors laminated a layer of liquid resins of different colors in a molding cell and moved a comb-like tool in the molding cell. Japanese Patent Application No. 8-286834 proposes a method of producing an artificial marble by curing after curing. In this method, a stripe pattern having a clear appearance can be easily formed, the pattern can be easily controlled, and the pattern can be formed continuously in the thickness direction.

[0005] However, simply by this method, the texture is flat or easily formed into a single pattern, and it is still insufficient in appearance in comparison with natural woody materials and other natural marbles. It was not satisfactory. In particular, there is room for improvement in the subtle colors, depth, texture, and luxury of natural products such as natural wood and natural stone.

For this reason, Japanese Patent Application No. Hei 9-135522 proposes an improved method of injecting a liquid resin in which a colorant is unevenly dispersed into the lowermost layer of a molding cell and moving a comb-like tool through the molding cell. In addition, it has made it possible to produce artificial marble having a natural marble-like stripe pattern rich in the subtle shades of wood and a natural appearance with a fine grained wood pattern or texture.

An object of the present invention is to provide a method for producing artificial marble in which patterns in which the distance between stripes changes in a more natural manner can be formed, and these patterns can be easily controlled.

Another object of the present invention is to provide a method for producing an artificial marble which can be formed continuously in the thickness direction and can exhibit a stripe pattern which does not disappear even when the surface is cut.

[0009]

That is, according to the present invention, at least two layers of different color liquid resins are injected into a molding cell in layers, and then a comb-like tool is used to form a tooth of the molding cell. In the method of manufacturing the artificial marble by moving the liquid resin laminated while contacting the bottom surface, and then hardening the liquid resin, while changing the tooth-to-teeth spacing of the comb-shaped tool in the liquid resin This is a method for producing artificial marble having a stripe pattern, which is characterized by being moved.

This method can be implemented by using a comb-shaped tool in which a handle and teeth of the comb-shaped tool are connected via a flexible member. Further, the present invention can also be implemented by using a plurality of comb-shaped tools and moving the liquid resin while relatively changing the distance between the teeth in the comb-shaped tool group.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the method of the present invention, first, a liquid resin as a raw material of artificial marble is injected into a molding cell. At this time, the liquid resin of a different color is injected so as to be in a layered state. Injected into the bottom layer is a liquid resin that exhibits the base color tone in significant aspects of the product. In order to laminate the liquid resin in layers, the simplest method is to inject one liquid resin into the molding cell and allow it to stand, and then inject another liquid resin without disturbing the interface. . In the present invention, at least two kinds of liquid resins having different color tones are used. Therefore, three or more liquid resins having different color tones may be laminated in three or more layers.

It is preferable that the liquid resin is laminated uniformly over the entire surface of the molding cell in order to control the appearance of the pattern. It does not affect the expression of the stalk. The thickness of the liquid resin laminate is not particularly limited,
It is preferable that the thickness of each layer is about 2 to 20 mm.
In particular, if the thickness of the lower layer liquid resin is too large, it is difficult to allow the upper layer liquid resin to reach the bottom surface of the molding cell, which is not preferable. On the other hand, if the thickness of the lower liquid resin layer is too small, the pattern is easily disturbed and control becomes difficult, and the obtained product is not preferable because the thickness of cutting is limited and the like, which causes problems in use.

The liquid resin used in the present invention is usually a mixture, and its composition is not particularly limited. A typical example is a mixture of a monomer such as methacrylic acid ester and a polymer thereof. A composition comprising a certain syrup, a filler, a coloring pigment and a curing catalyst is exemplified. Examples of the filler include inorganic fillers such as aluminum hydroxide, magnesium hydroxide, and calcium hydroxide, and organic fillers such as wood flour. Examples of the color pigment include white titanium oxide and zinc sulfide; yellow iron oxide yellow;
Black iron oxide black; red iron oxide red; blue ultramarine blue, phthalocyanine blue and the like. As the curing catalyst, tertiary butyl peroxymaleic acid, benzoyl peroxide, cumene hydroperoxide, tertiary butyl hydroperoxide,
Lauroyl peroxide, azobisisobutyronitrile and the like can be mentioned. In addition to these components, various components conventionally known as additive components of artificial marble, for example, dyes, ultraviolet absorbers, flame retardants, mold release agents, flow agents, thickeners, polymerization inhibitors, and oxidants Inhibitors and the like can be added.

The viscosity of the liquid resin is 300-5000.
A cp range is preferred. If the viscosity is too high or too low, it tends to be difficult to develop and control a stripe pattern. Also, by appropriately selecting the viscosity of the liquid resin, sedimentation of additives such as a filler and a colorant can be prevented.

In the method of the present invention, the liquid resin to be initially injected into the molding cell is also disclosed in Japanese Patent Application No. 9-135522.
It is also possible to use a liquid resin in which the coloring agent proposed in the above is dispersed non-uniformly. The liquid resin in which the colorant is dispersed non-uniformly means that one type of colorant is dispersed in the liquid resin, and that the color concentration of the liquid resin is uneven due to the non-uniform dispersion, Two or more types of colorants are dispersed in the liquid resin, and the colorants of the liquid resin have uneven color due to non-uniform dispersion of the colorants. When a liquid resin in which such a colorant is dispersed non-uniformly is used, a natural appearance in which the plane of the texture disappears from the obtained artificial marble and the quality is remarkably improved is obtained. Note that a liquid resin in which a colorant is non-uniformly dispersed can also be used as the liquid resin to be laminated on the upper layer.

According to the present invention, the liquid resin laminated and injected into the molding cell in this manner, using a comb-shaped tool, with the tips of its teeth contacting the bottom surface of the molding cell. The resin is moved through the liquid resin as if combing. When the comb tool is moved in the liquid resin, an exaggerated expression, in the trace of the teeth of the comb tool passing, there is a dent in which the liquid resin is pushed away, into which the upper layer of a different color liquid resin flows Will be. For this reason, the upper layer of a different color liquid resin penetrates into the trace of the teeth of the comb-shaped tool up to the bottom surface of the molding cell, and when the bottom surface is a significant surface, a stripe pattern is formed on the trace of the teeth of the comb-shaped tool. Will be formed.

In the method of the present invention, it is necessary that the upper layer of a different-colored liquid resin flows into the trace of the teeth of the comb-shaped tool,
If only the liquid resin in the lower layer portion flows into this, a stripe pattern is not formed. For this purpose, it is necessary that a depression can be formed in the trace of passage of the tooth. Since various factors such as the viscosity of the liquid resin, the moving speed of the comb-shaped tool, and the shape of the comb-shaped tool are interrelated to the occurrence of the dent, conditions for successfully generating the dent are uniformly set. Can not be determined. FIG. 1 is a schematic diagram showing such a situation. In this figure, the distance between the teeth of the comb-shaped tool does not change.

In the method of the present invention, when moving the comb-like tool through the liquid resin, the comb-like tool is moved while changing the distance between the teeth of the comb-like tool. When the distance between the teeth changes, the stripe pattern as a trace of the teeth fluctuates and the distance changes, so that a more natural artificial marble can be obtained.

Although there are several specific means for moving the comb-shaped tool while changing the tooth-to-teeth spacing, the first mode is that the handle and the tooth are connected via a flexible member as a comb-shaped tool. It is a method to use the thing.

That is, as shown in FIG. 2, a comb-shaped tool 1 in which the handle 4 and the teeth 5 are not directly joined but are connected via a flexible connecting member 6 is used. When the teeth are moved through the liquid resin using such a comb-shaped tool, the position of each tooth in the liquid resin is slightly changed due to the resistance of the teeth from the liquid resin. It will change slightly. Also, the width of the stripe changes because the force applied by the tip of the tooth to the bottom of the cell also changes. In particular, when the comb-shaped tool is gently meandered in the liquid resin, these changes are amplified, and a pattern having a natural fluctuation and a change in stripe interval and thickness can be obtained.

As the flexible connecting member for connecting the handle and the tooth, the movement of the tooth portion does not follow the movement of the handle portion of the comb-shaped tool if the movement of the tooth portion completely coincides with that of the comb-shaped tool. Any one can be used as long as it is a connection means having no restoring force, such as a thread, a string, a chain, or a film, or an elastic connecting means having a restoring force, such as a spring.

In this case, it is necessary that the tip of the tooth portion is in contact with the bottom surface of the cell during the movement of the comb-shaped tool. Preferably does not float from the bottom surface.

In a second mode of moving the comb-shaped tool while changing the tooth-to-teeth spacing, a plurality of comb-shaped tools are used, and the distance between the teeth in the comb-shaped tool group is relatively changed. This is a method of moving in a liquid resin while moving. That is, by moving the plurality of comb-shaped tools while changing the positional relationship, the distance between the teeth in the entire comb-shaped tools, particularly the distance between the teeth in the direction perpendicular to the moving direction of the comb-shaped tools. Is moved in the liquid resin while relatively changing.

In this case, the movement of these comb-shaped tools may be performed manually, or may be moved by automatic control means in accordance with pre-programmed fluctuation movement.

The moving speed of the teeth of the comb-shaped tool is important in relation to the viscosity of the liquid resin. If the moving speed of the teeth is too slow, no depression can be formed in the trace of the passage of the teeth, so that the liquid resin of a different color in the upper layer cannot reach the bottom of the molding cell, and a stripe pattern cannot be formed. Generally, the moving speed of the comb tool is 1
It is preferably about 10 cm / sec to 10 cm / sec. The comb tool may be moved linearly, but is preferably moved in a meandering manner. In particular, in the case of the second embodiment in which a plurality of comb tools are used, the interval between the teeth in the comb tool group cannot be changed unless at least some of the comb tools are meandering.

The comb-shaped tool used in the present invention is preferably made of a material which is inert to the liquid resin and does not exhibit adhesiveness, especially for the tooth portion. Examples thereof include metals and organic materials coated with polytetrafluoroethylene.

FIG. 3 is a schematic view of a comb tool used in the method of the present invention, particularly in the second embodiment. As the form of the teeth of the comb-shaped tool, it is appropriate that the length of the teeth is sufficiently longer than the thickness of the laminated liquid resin so as not to cause unnecessary disturbance to the liquid resin in the upper layer. Further, the width of the teeth (the length perpendicular to the moving direction of the teeth) is preferably 1 to 20 mm. The width of the teeth does not match, but does affect, the width of the stripe to be formed. The thickness of the teeth (the length in the direction of movement of the teeth) may be any thickness as long as the mechanical strength of the teeth is maintained, and does not significantly affect the formation of the stripe pattern. The streamlined shape is not appropriate as the cross-sectional shape of the tooth, and a square shape that generates turbulence in the liquid resin at the trace of the tooth is appropriate. Further, the shape of the tip of the tooth preferably has a flat surface so that it can be in close contact with the bottom surface of the molding cell. The number of teeth may be one for the comb tool used in the second embodiment, and an appropriate number of teeth and an appropriate tooth spacing can be selected according to a desired stripe pattern.

After the comb-like tool is moved while changing the tooth-to-teeth spacing as described above, the liquid resin is cured according to a conventional method, and after curing, the cured product is taken out of the molding cell to obtain an artificial marble. In the obtained artificial marble, a stripe pattern is formed on the contact surface with the bottom of the molded cell. Since the stripe pattern thus formed is formed based on the flow mixing of liquid resins of different colors, it is a line pattern having a natural fluctuation different from that drawn by a ruler. Also, by properly selecting the color tone of the liquid resin, the number of comb-shaped tools, and the spacing between the teeth, artificial marble having a grain-like wood grain pattern can be produced.

In the above, the implementation of the method of the present invention in a batch type casting method has been described. In the continuous cast molding method, a stainless steel belt moving as a molding cell and rubber or resin placed on both sides thereof are used. A frame for damming the liquid resin prepared in the above is used. Accordingly, in this case, as shown in FIG. 4, the comb-shaped tool is stopped in the moving direction of the stainless steel belt 11 and is gently reciprocated in the direction perpendicular to the belt moving direction. The method of the present invention can be carried out such that the tool moves in a swinging manner relative to the liquid resin.

The artificial marble produced by the method of the present invention can be used for applications such as kitchen top plates, vanities, bathtubs, tables, wall materials, furniture, and interior accessories in houses.

[0031]

The present invention will be described more specifically below with reference to examples. In the examples, “%” and “part” mean “% by weight” and “part by weight”, respectively. Example 1 1000 parts of methyl methacrylate syrup (hereinafter abbreviated as "syrup") comprising a mixture of 20% polymethyl methacrylate and 80% methyl methacrylate, aluminum hydroxide powder (BS-33, trade name, Nippon Light Metal) (stock)
1630 parts, ethylene glycol dimethacrylate 1
2 parts, tert-butyl peroxymaleic acid 20
And 2 parts of deionized water were mixed and stirred with a mixer to obtain a mixed slurry. After defoaming the mixed slurry in a vacuum vessel, 0.1 part of glycol dimercaptoacetate and 8 parts of a slurry in which 25% of calcium hydroxide was dispersed in syrup were added and stirred to prepare a base mix. The viscosity of this base mix was 1000 cps.

Two-thirds of the base mix was separated and further divided into three parts, each having a colorant composition No. 1 shown in Table 1. 1 to 3 (unit is part) were added, and the mixture was stirred until it became uniform. Next, the obtained three kinds of colored mixes were transferred to a pan-shaped container, and were stirred gently with a stirring rod for 3 seconds so as not to be completely mixed to prepare an incomplete mixed mix. It was injected so as to have a thickness of 9 mm.

On the other hand, the colorant composition No. 4 was added and mixed uniformly, and the mixture was poured onto the incomplete mixed mix in the mold to laminate a mixed mix layer having a thickness of 4.5 mm.

Thirty teeth made of polytetrafluoroethylene having a length of 120 mm, a width of 5 mm, and a thickness of 3 mm and having a lead weight attached to the upper end thereof were formed at irregular intervals of 10 to 40 mm and 60 mm in length. A comb-shaped tool having a shape as shown in FIG. 2 attached to a handle via a thread was prepared. The comb-shaped tool is immersed in one end of the mold, and the teeth are brought into contact with the bottom surface of the mold, and the pattern is moved at 50 mm / sec while slightly meandering in the laminated mix toward the other end of the mold. Was. Thereafter, the mold was covered with the lid, and the resin was cured while being kept warm for 30 minutes. After the resin was cured, the cured product was taken out of the mold to obtain an artificial marble having a wood grain pattern on the contact surface with the bottom surface of the mold. .

The resulting artificial marble had a stripe pattern like a natural marble in which the distance between wood grains and the thickness were slightly changed. Even when the surface was polished by about 0.5 mm, the basic stripe pattern hardly changed.

[0036]

[Table 1] Example 2 A stainless steel belt moving as a molding cell and a rubber frame installed on both sides thereof were used. On this stainless steel belt, an incompletely mixed mixed layer having the same composition as in Example 1 and a thickness of 9 mm was further formed. Was mixed with a mixed mix layer having a thickness of 4.5 mm.

The stainless steel belt was moved at a speed of 3000 mm / min, and immediately after passing through the installation portion of the comb-shaped tool after the lamination of the mix layer. In this case, three comb-shaped tools having 1 to 30 teeth as shown in FIG. 3 are arranged in parallel at intervals of 80 mm, and each pattern is formed at a rate of about 3 times / minute in a direction perpendicular to the belt moving direction. Reciprocating motion (moving distance of about 50 mm) was separately performed at a slow speed. Then, after the surface of the laminated mix was pressed with a gauge roll to make the thickness uniform, the mixture was kept warm while being moved by a belt and cured to obtain an artificial marble.

The appearance of the obtained artificial marble was similar to that obtained in Example 1 and had a wood grain pattern like a natural wood in which the grain spacing was slightly changed.

Example 3 An artificial marble was obtained in the same manner as in Example 1 except that the colorant compositions 1 to 4 were changed to colorant compositions 5 to 8, respectively. The appearance of the obtained artificial marble has a wood-grain pattern such as a natural wood in which the distance between wood grain and the thickness are slightly changed, and the surface thereof is 0.5 mm
Even after the polishing, the basic grain pattern hardly changed.

[0040]

According to the production method of the present invention, a stripe pattern having a natural marble appearance rich in texture and depth, or a wood grain pattern having a subtle hue and natural appearance of wood is provided. Artificial marble can be formed in a simple manner. In particular, it is possible to produce a product having a very natural appearance in which the intervals between stripes are not uniform. In addition, since this stripe pattern is formed continuously also in the thickness direction of the artificial marble, the pattern does not disappear even if the surface of the artificial marble is cut, and a continuous stripe pattern is developed in the cut portion. be able to. Further, since the components of the artificial marble base portion and the stripe pattern portion are substantially the same, there is no reduction in the mechanical properties of the artificial marble due to the provision of the pattern.

[Brief description of the drawings]

FIG. 1 is a schematic view illustrating a manufacturing method of the present invention.

FIG. 2 is a view showing an example of a comb tool used in the manufacturing method of the present invention.

FIG. 3 is a view showing another example of a comb tool used in the manufacturing method of the present invention.

FIG. 4 is a partially cutaway schematic view showing an example of continuously performing the manufacturing method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Comb tool 2, 3 Liquid resin 4 Handle 5 Teeth 6 Flexible connecting member 7 Weight 8 Comb tool group 9 Stainless steel belt 10 Frame 11 Gauge roll

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-10-128779 (JP, A) JP-A-10-323848 (JP, A) JP-A-60-199617 (JP, A) JP-A-57- 87913 (JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) B29C 39/02-39/12 B29C 39/22-39/24

Claims (4)

(57) [Claims] 1. A liquid resin of a different color is laminated into at least two layers in a molding cell and injected into the molding cell. Then, a comb-shaped tool is laminated while bringing its teeth into contact with the bottom surface of the molding cell. In the method of manufacturing artificial marble by moving the inside and then curing the liquid resin, having a stripe pattern characterized by moving in the liquid resin while changing the interval between the teeth of the comb-shaped tool Manufacturing method of artificial marble. 2. A comb-shaped tool in which a handle and teeth of the comb-shaped tool are connected via a flexible member.
The manufacturing method as described. 3. The manufacturing method according to claim 1, wherein a plurality of comb-shaped tools are used, and the comb-shaped tools are moved in the liquid resin while relatively changing the distance between the teeth in the group of comb-shaped tools. 4. The production method according to claim 1, wherein a liquid resin in which a colorant is non-uniformly dispersed is injected into the lowermost layer of the molding cell.