KR20070025445A - Artificial marble having natural marble pattern and process for preparing the same - Google Patents

Abstract

A method of fabricating an artificial marble having natural marble pattern is provided to produce the artificial marble with marble pattern greatly similar to that of natural marble by preparing both of a base resin slurry and a coloring slurry that have different viscosities and specific gravities and simply blending the slurries together. The artificial marble has one base area and at least two color areas having different colors and specific gravities and a difference of the colors and the specific gravities ranges from 0.01 to 1.0. The artificial marble is fabricated by a process comprising the steps of: (a) preparing a base slurry used as the base area; (b) preparing a color slurry used as the color area; (c) laminating respective slurries by introducing the base slurry and the color slurries into a chute(3) having partitions(4a,4b); and (d) passing the slurries through the partitions to make the slurries partially blended based on difference of the specific gravities and the viscosities while forming barriers between the slurries.

Description

Artificial marble having natural marble pattern and process for preparing the same {Artificial marble having natural marble pattern and process for preparing the same}

1 is a manufacturing process of the artificial marble according to the present invention.

2 is a photograph of artificial marble according to the present invention.

3 is an enlarged photograph of FIG. 2.

<Description of the symbols for the main parts of the drawings>

1a, 1b: colored slurry hopper

2: base slurry hopper

3: chute

4a, 4b: slurry partition

5: mixed slurry

6: steel belt

The present invention relates to artificial marble and a method for manufacturing the same, and more particularly, acrylic resin or unsaturated polyester resin as the base resin, and in the same content, the composition of the resin, filler and additives in the same content by varying the specific gravity and viscosity marble By forming a pattern, in addition to the method of using a chip to represent the pattern in the manufacturing of conventional acrylic or unsaturated polyester artificial marble, artificial marble slurry has a similar composition but at least two kinds by giving a difference in specific gravity and viscosity It relates to artificial marble having a natural pattern and a method for producing the same by preparing and kneading the same by itself without any external power by the difference in specific gravity and viscosity.

Artificial marble is a synthetic synthetic material that combines natural stone powder or minerals with resin components (acrylic, unsaturated polyester, epoxy, etc.) and adds various pigments and additives to realize the texture of natural stone. And unsaturated polyester artificial marble.

The acrylic artificial marble and the unsaturated polyester artificial marble have unique strength and color tone of a solid material, and in particular, the acrylic artificial marble has excellent processability and weather resistance. Acrylic artificial marble is lighter and more non-porous than natural marble, has an elegant hue that is inferior to natural marble, excellent strength and weather resistance, and can be distinguished from natural marble because of its excellent workability comparable to wood.

On the other hand, unsaturated polyester artificial marble has a disadvantage in that weatherability and heat resistance are poorer than acrylic artificial marble and are difficult to thermoform.However, since the refractive index is similar to that of aluminum hydroxide, which is used as a filler, the polymer is excellent in transparency and natural and deep like natural stone. There is an advantage that can realize a sense of appearance.

Such artificial marble is recently used in various applications such as various top plate materials, dressing tables, wash basins, tables, wall materials, flooring materials, furniture, interior materials, indirect lighting panels, interior accessories.

Pigments and chips are mostly used as a means of indicating the color and shape of the artificial marble, and the components of the chip are manufactured using the same or different raw materials as the artificial marble, and have various colors and particle sizes.

However, in the use of chips, even if various types of chips are used for different colors and their sizes are varied, they show a great difference from the pattern of natural marble.

That is, due to the heterogeneous color difference between the base color of the artificial marble and the monochromatic chip, there is a limit in expressing the texture of natural color. In addition, the method of using a pigment of the existing methods can not only represent one color, there is also a limit.

In Korean Patent No. 464176, two or more liquid resins to which pigments of different colors are added are respectively supplied through two or more supply ports; Partially mixing the supplied two or more liquid resins in a line mixer installed between a supply port and an outlet; Supplying the partially mixed liquid resin mixture to a movable steel belt through an outlet nozzle connected to an orthogonal one-axis robot device to move from side to side, control of movement speed, and stop for a predetermined time; And stop the outlet nozzle for a predetermined time at the designated position of the steel belt to spread the liquid resin to form an irregular pattern; Disclosed is a method for producing an acrylic artificial marble, comprising the steps. However, this patent uses a separate external power, such as a line mixer, robot apparatus, and the present invention using the chute and the manufacturing method is fundamentally different, as in the present invention the configuration using the specific gravity and viscosity difference of the slurry and accordingly Natural mixing effects are not disclosed.

In Japanese Patent Application Laid-Open No. Hei 5-68611, an inorganic marble or a filler such as a glass filler, a curing agent, a pigment, or the like is mixed with a thermosetting resin to form a raw material, and the raw material is injected into a shape and cured. The artificial marble molded body is formed in the height direction between the first color tone layer by the first pigment, the second color tone layer by the second pigment, and the first and second color tone layers. An artificial marble molding is disclosed which has a third color tone layer by a third pigment in a mixture of two pigments. This invention is also fundamentally different from the present invention using the chute in the manufacturing method, and as in the present invention, the composition using the specific gravity and viscosity difference of the slurry and the natural mixing effect thereof are not disclosed.

The present inventors have attempted to develop a shape having a pattern close to the natural stone by using a colored slurry containing a pigment but not completely mixed with the base slurry and naturally mixed during curing.

Accordingly, it is an object of the present invention to provide an artificial marble and a method for producing the same, which have a texture closer to that of natural stone by mixing the colored slurry containing the pigment used in the existing artificial marble into the base slurry by a new method.

In order to achieve the above object, the present invention provides an artificial marble having one base region and two or more color regions having different colors and specific gravity.

In the present invention, the specific gravity difference between the background area and the color area is 0.01 to 1.0, preferably 0.01 to 0.3. As a driving force for spontaneous mixing by gravity without additional external power, the specific gravity difference should be at least 0.01 or more, and if the specific gravity difference is too large, the natural partial mixing effect may be lowered.

In the present invention, the specific gravity of the base region is preferably 1.5 to 1.75 in the specific gravity range of a conventional artificial marble raw material slurry, and in general, after preparing a colored slurry such that the specific gravity of the color region is larger than the base region, batch lamination is performed as an upper layer. In this case, the colored slurry spreads downward due to the specific gravity difference, thereby forming a natural pattern.

In addition, the present invention comprises the steps of (a) preparing a base slurry to be used as the base area; (b) preparing a colored slurry to be used as the color gamut; (c) stacking the base slurry and two or more colored slurry into a chute equipped with a partition to form a layer for each slurry; And (d) after passing through the partition provides a method for producing artificial marble comprising the step of partially mixing each slurry by themselves bound by the specific gravity and viscosity difference between each slurry.

It is preferable to prepare the viscosity and specific gravity of the slurry differently by adjusting the content of the resin and the filler used in each slurry in the production method.

In the present invention, not only the specific gravity difference of the slurry but also the viscosity of each slurry can be prepared differently to maximize the natural mixing effect of the slurry. Specifically, the viscosity of the base slurry and the colored slurry is preferably equal to or less than 90 Poise, the viscosity of the base slurry is preferably 60 to 120 Poise, it is preferable that the viscosity of the colored slurry is lower than the base slurry.

On the other hand, it is preferable that there is no difference in specific gravity and viscosity between colored slurries. Naturally, due to the difference in gravity, it must be mixed down to form a good pattern when two or more colored slurries are simultaneously lowered.

Preferably, the base slurry is introduced to the bottom of the chute, and a colored slurry having a higher specific gravity and a lower viscosity than the base slurry is introduced into the upper part of the base slurry through a partition.

In addition, it is preferable to supply the mixed slurry partially mixed in the step (d) to the continuously movable steel belt to cure while maintaining at 40 to 60 ℃.

The present invention relates to artificial marble prepared using two or more colored slurry having different colors and a base slurry showing the main color of artificial marble.

In the artificial marble of the present invention, a pigment is added to a base slurry and the same raw material to prepare two or more kinds of colored slurry having different colors, and then, each slurry is put into a partition plate of a chute and laminated. It is made by partially mixing naturally without any external power by the specific gravity and viscosity difference, and then curing the mixed slurry to prepare a plate obtained by polishing.

The base slurry is prepared by kneading a raw material composition including 100 to 200 parts by weight of an inorganic filler, 0.1 to 10 parts by weight of a crosslinking agent, and 0.1 to 10 parts by weight of a polymerization initiator, based on 100 parts by weight of an acrylic or unsaturated polyester syrup.

The colored slurry is 100 to 200 parts by weight of an inorganic filler, 0.1 to 10 parts by weight of a crosslinking agent, 0.1 to 10 parts by weight of a polymerization initiator, and 0.1 to 10 parts by weight of a pigment to express color based on 100 parts by weight of an acrylic or unsaturated polyester syrup. It is made by kneading a raw material composition containing a part.

In the mixing step of the base slurry and the colored slurry, the base slurry and the colored slurry are supplied to the chute provided with partitions and mixed. In this process, the specific gravity and viscosity of the colored slurry are made to be different from the specific gravity and viscosity of the base slurry, and the difference in specific gravity is 0.01 to 1.0, preferably 0.01 to 0.3, and the viscosity is the same as the base slurry or the base. It is preferable to exist in the range below 90 Poise or less than a slurry.

The specific gravity of the base slurry is 1.5 to 1.75, the viscosity is preferably 60 to 120 Poise. If the viscosity is lower than this range, it is mixed with the coloring slurry so well that a natural pattern does not come out, and if it is larger than this range, it does not mix well with the coloring slurry.

When the specific gravity of the colored slurry is greater than the specific gravity of the base slurry, when the colored slurry is supplied above the base slurry in the feed chute, the colored slurry spreads downward due to the specific gravity difference during curing, and a natural pattern appears after curing. In addition, the viscosity of the colored slurry should be lower than that of the base slurry. When the viscosity of the colored slurry is higher than that of the base slurry, the effect of producing a natural pattern while mixing properly is significantly reduced.

The slurry thus mixed is fed into a continuously movable steel belt and then molded into a flat plate and cured. At this time, the steel belt receives the heat while passing through the oven and hardens as the temperature increases. As the viscosity drops to the lowest at 40 to 60 ° C., the steel belt shows a natural pattern in the plate.

Artificial marble of the present invention, in addition to the pattern represented by the coloring slurry, by adding 0.1 to 20 parts by weight of chips separated by size in the base slurry to make the colors more colorful, even small colored acrylic chips of 30 mesh or less To 0.1 to 20 parts by weight can be added to the pattern represented by the chip to the color represented by the pigment.

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

1 is a manufacturing process diagram of the artificial marble according to the present invention, when specifically described the manufacturing process of artificial marble as follows.

First, a base slurry and a coloring slurry are mix | blended.

Specifically, the base slurry is 100 to 200 parts by weight of inorganic filler, 0.1 to 10 parts by weight of crosslinking agent, 0.1 to 10 parts by weight of polymerization initiator, and 0 to 20 parts by weight of chip based on 100 parts by weight of acrylic resin syrup or unsaturated polyester resin syrup. Slurry.

The colored slurry is 100 to 200 parts by weight of an inorganic filler, 0.1 to 10 parts by weight of a crosslinking agent, 0.1 to 10 parts by weight of a polymerization initiator, and 0 to 20 chips having a size of 30 mesh or less, based on 100 parts by weight of an acrylic resin syrup or an unsaturated polyester resin syrup. It is a slurry consisting of 0.1 to 10 parts by weight of the pigment for expressing parts by weight, color.

For chips in the colored slurry and the base slurry, 100 to 250 parts by weight of inorganic filler, 0.1 to 10 parts by weight of crosslinking agent, 0.1 to 3 parts by weight of crosslinking accelerator, based on 100 parts by weight of acrylic resin syrup or unsaturated polyester resin syrup, After mixing 0.1 to 10 parts by weight of the pigment to make a flat plate, and then cured in an oven and then crushed to a diameter of 100 to 2.5 Mesh using a crusher, and produced in various sizes within the range of 100 to 2.5 Mesh mesh Screen by size using net.

When blending the base and the colored slurry in the present invention, when using the acrylic resin syrup as a raw material has a disadvantage that the color is turbid, but the distinction of the color appears clearly and can express a clear and colorful pattern, unsaturated polyester as a raw material In this case, color exhibits the transparency of the unsaturated polyester inherent transparency, and compared with the case of acrylic resin syrup, it has a better mixing property, so the pattern feels closer to natural stone.

The resin of the base slurry and the resin of the colored slurry may be differently used as the acrylic resin and the unsaturated polyester resin, respectively. However, since the base slurry and the colored slurry are not completely mixed, the interface between the slurries may crack after curing.

Unsaturated polyesters usable in the present invention are not particularly limited, and in general, almost any unsaturated polyester may be used. For example, α, β-unsaturated dibasic acids or a mixture of diunsaturated dibasic acids and saturated dibasic acids are mixed so as to have a ratio of 0.8 to 1,2 as molar ratios of polyhydric alcohols and alcoholic hydroxyl groups / carboxyl groups, and carbon dioxide gas and nitrogen Condensation reaction at a temperature of 140 to 250 ℃ in an inert gas stream such as gas, and the acid value obtained by the method of gradually raising the temperature depending on the progress of the reaction while removing the generated water, the range of about 5 to 40, molecular weight 1,000 to 5,000 The unsaturated polyester can be used.

The α, β-unsaturated dibasic acid and saturated dibasic acid used herein include maleic anhydride, citraconic acid, fumaric acid, itaconic acid, phthalic acid, and phthalic acid. Phthalic acid, isophthalic acid, terephthalic acid, terephthalic acid, succinic acid, adipic acid, sebacic acid, tetrahydrophthalic acid, and the like.

If necessary, polybasic acids such as monobasic acids such as acrylic acid, propionic acid and benzoic acid, and trimellitic acid and tetracarboxylic acid of benzol can also be used.

Examples of the polyhydric alcohols include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, 1,3-butylene glycol, hydrogenated bisphenol A, trimethylolpropane monoaryl ether, and neopentyl. Glycol, 2,2,4-trimethyl-1,3-pentanediol, glycerin and the like can be used.

Acryl monomer is preferred as a polymerizable monomer of the acrylic resin syrup used in the preparation of artificial marble. Specifically, the acrylic resin syrup is a methacrylate monomer selected from methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, benzyl methacrylate and glycidyl methacrylate alone or It is also a mixture of two or more kinds, and a mixture of a polymer in which a methacrylate monomer and a portion thereof are polymerized may be used. Of these, methyl methacrylate is particularly preferred. The content of the polymer in the syrup is preferably 10 to 50% by weight.

The crosslinking agent used in the present invention is a polyfunctional acrylic monomer which crosslinks with the acrylic resin syrup including an intramolecular copolymerizable double bond, and is ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimetha Single or a mixture of two or more selected from methacrylate, tetraethylene glycol dimethacrylate, 1,6-hexane diol dimethacrylate, polybutylene glycol dimethacrylate and neopentyl glycol dimethacrylate, these Ethylene glycol dimethacrylate is especially preferable.

If the crosslinking agents are not used or are used too little, unevenness of the surface is generated, bubbles are generated in the upper and lower portions of the artificial marble, and thus the bonding strength between the raw materials is reduced, and the heat resistance and heat discoloration resistance are deteriorated. If too much crosslinking agent is used, phase separation of chips occurs, which causes many problems in artificial marble pattern. Therefore, the amount of the crosslinking agent is preferably 0.1 to 10 parts by weight based on 100 parts by weight of the base resin syrup.

Inorganic fillers used in the present invention are aluminum hydroxide, magnesium hydroxide, calcium aluminate, etc., the refractive index is preferably 1.57 to 1.62, can be used alone or in combination of two or more. The inorganic filler preferably has a surface treated with a silane coupling agent, titanate coupling agent or stearic acid for dispersibility with the resin, improvement of mechanical strength of the product, and prevention of precipitation. The preferred amount of the inorganic filler is 100 to 200 parts by weight based on 100 parts by weight of the base resin syrup.

The polymerization initiator used in the present invention serves as a curing agent, and as organic peroxide, benzoyl peroxide, diacyl peroxide such as dicumyl peroxide, butylhydro peroxide, hydroperoxide such as cumylhydro peroxide, t -Butyl peroxy maleic acid, t-butylhydro peroxide, acetyl peroxide, lauroyl peroxide, azobisisobutyronitrile, azobisdimethylvaleronitrile, t-butyl peroxy neodecanoate ( Neodecanoate), t-amyl peroxy 2-ethyl hexanoate, or a mixture of two or more thereof. In addition, a mixture of peroxides and sulfonic acids of amines or mixtures of peroxides and cobalt compounds can be used to allow polymerization and curing to be carried out at room temperature. The content of the polymerization initiator is preferably 0.1 to 10 parts by weight based on 100 parts by weight of the base resin syrup, and is generally used together with the polymerization accelerator.

Moreover, radical carriers, such as mercaptan compounds, such as a normal dodecyl mercaptan, a tertiary dodecyl mercaptan, a benzyl mercaptan, and a trimethyl benzyl mercaptan, can be used. The content of the radical carrier is preferably 0.1 to 5 parts by weight based on 100 parts by weight of the base resin syrup.

In addition, the composition is conventionally known as an additive component of artificial marble, a silicone-based or non-silicone-based antifoaming agent; Silane-based, acid-based, or titanate-based coupling agents mainly composed of trimethoxysilane; Organic or inorganic pigments or dyes; Phenyl salicylate-based, benzophenone-based, benzotriazole-based, nickel derivative-based or radical scavenger-based ultraviolet absorbers; Halogen-based, phosphorus- or inorganic metal-based flame retardants; Stearic acid type or silicone type release agent; Catechol-based or hydroquinone-based polymerization inhibitors; It may further include one or more additives selected from phenolic, amine, quinone, sulfur or phosphorus antioxidants.

Next, the base slurry and the colored slurry prepared above are supplied to the chute 3 through the base slurry hopper 2 and the colored slurry hoppers 1a and 1b, respectively.

The chute (3) means a ramp, one side of the chute (3) is provided with a plurality of slurry partitions (4a, 4b), the other side is adjacent to the steel belt (6).

The partitions 4a and 4b are inclined downward in the advancing direction for smooth flow of the slurry in the form of a flat plate, as shown in the figure. The number of partitions 4a and 4b is determined according to the number of colored slurries used, and is arranged in two stages in the figure.

When supplying the slurry to the chute 3, the base slurry is charged at the lower end of the chute 3, and a colored slurry having a higher specific gravity and lower viscosity than the base slurry is charged at the top of the base slurry. When two kinds of colored slurry are used as shown in the figure, the second colored slurry from the second colored slurry hopper 1b is introduced between the first partition 4a and the second partition 4b, and the first The first colored slurry from the colored slurry hopper 1a is fed to the top of the second partition 4b.

The base slurry and the two kinds of colored slurries separated through the partitions 4a and 4b are temporarily layered to form a stack of three layers. Thus, each slurry is divided into the partitions 4a and 4b of the chute 3. The reason for the separate input by use is that when the slurry is added to the chute 3 without the partitions 4a and 4b, the slurry can be completely mixed from the beginning, and is separated temporarily using the partitions 4a and 4b. Through the laminated structure, natural mixing effect by specific gravity and viscosity difference can be maximized.

Next, after passing through the partitions (4a, 4b) and supplied to the continuously movable steel belt (6) of the mixed slurry (5) naturally mixed partially without a separate external power by the specific gravity and the viscosity difference to form a flat plate Harden. Partial mixing of each slurry due to specific gravity and viscosity difference still occurs during casting and curing. At the time of hardening, the steel belt 6 receives heat while passing through an oven, and hardens as the temperature increases. As the temperature drops to the lowest at 40 to 60 ° C., the steel belt 6 exhibits a natural pattern in the flat plate.

Finally, after hardening is completed, the upper and lower surfaces of the plate are polished to a certain thickness to complete the finished product of artificial marble of natural stone texture.

Figure 2 is a photograph of the artificial marble according to the present invention, Figure 3 is an enlarged photograph of Figure 2, it can be seen that the natural pattern is formed due to the natural mixing effect of the specific gravity and viscosity difference between the base slurry and the colored slurry.

Hereinafter, although an Example is given and this invention is demonstrated in detail, this invention is not limited to this.

Example 1

1. Preparation of raw material slurry

1) Preparation of Base Slurry

100 parts by weight of methyl methacrylate syrup consisting of a mixture of 30% by weight of polymethyl methacrylate and 70% by weight of methyl methacrylate, 160 parts by weight of aluminum hydroxide, 0.2 parts by weight of t-butyl peroxy neodecanoate, 0.3 parts by weight of t-amyl peroxy 2-ethyl hexanoate, 3 parts by weight of ethylene glycol dimethacrylate, 0.2 parts by weight of normaldodecyl mercaptan, 0.2 part by weight of BYK 555 (BYK-Chemie, Germany) as an antifoaming agent, 0.75 parts by weight of BYK 900 (BYK-Chemie, Germany) as a coupling agent and 0.2 parts by weight of Hisorp-P (LG chemical) as a UV stabilizer (absorption) were mixed to prepare a slurry to be used as a base material. At this time, the specific gravity of the base slurry was 1.61, the viscosity was 70 Poise.

2) Preparation of Colored Slurry

100 parts by weight of methyl methacrylate syrup consisting of a mixture of 22% by weight of polymethyl methacrylate and 78% by weight of methyl methacrylate, 180 parts by weight of aluminum hydroxide, 0.2 parts by weight of t-butyl peroxy neodecanoate, 0.3 parts by weight of t-amyl peroxy 2-ethyl hexanoate, 3 parts by weight of ethylene glycol dimethacrylate, 0.2 parts by weight of normaldodecyl mercaptan, 0.2 part by weight of BYK 555 (BYK-Chemie, Germany) as an antifoaming agent, 0.75 parts by weight of BYK 900 (BYK-Chemie Co., Germany) as a coupling agent, 0.2 parts by weight of Hisorp-P (LG Chemistry) as a UV stabilizer (absorption), and 0.3 parts by weight of a pigment to express color are used. Eggplant produced two color book slurry. At this time, the specific gravity of the two colored slurry was 1.66, the viscosity was 52 Poise.

2. Manufacture of artificial marble

The base slurry and the two colored slurry prepared above were supplied to the chute 3 through the base slurry hopper 2 and the colored slurry hoppers 1a and 1b, respectively. At this time, the base slurry was added to the lower end of the chute (3), and a colored slurry having a higher specific gravity and lower viscosity than the base slurry was added to the top of the base slurry, specifically, as shown in FIG. 1, the second colored slurry hopper 1b. The second colored slurry from) is introduced between the first partition 4a and the second partition 4b, and the first colored slurry from the first colored slurry hopper 1a is placed on top of the second partition 4b. It was. At this time, 11-12 weight part of each coloring slurry was added with respect to 100 weight part of base slurries.

The base slurry and the two kinds of colored slurries separated through the partitions 4a and 4b were temporarily layered to form a laminate of three layers. Partially blended naturally without external power.

The mixed slurry (5) was fed to a continuous movable steel belt (6) and molded into a 14 mm thick flat plate, and then passed through an 80 ° C hot air oven to cure while maintaining the temperature of the mixed slurry (5) at 50 ° C. The colored slurry, which was located at the top during curing, was mixed down naturally due to differences in specific gravity and viscosity, resulting in a natural texture. After curing was completed, the upper surface of the plate was polished to a thickness of 1 mm and the lower surface to a thickness of 2 mm to make artificial marble of natural stone texture.

Example 2

It was prepared in the same manner as in Example 1, but 20 parts by weight of a single solid color chip was used in preparing the base and the colored slurry.

In general, artificial marble made of acrylic resin is used in various applications as kitchen tops and various interior materials due to the advantages such as lightness, weather resistance and thermal properties as well as excellent processability. However, compared to natural marble, they could not express all kinds of patterns and colors. In particular, the pattern of the color that can be continued by a combination of chips consisting of a single color gives a monotonous feeling, there was a limit to the color and pattern of the common natural stone texture.

Accordingly, the present invention improves this problem, and as a raw material to the two or more kinds of colored slurry having different colors and the base slurry showing the main color of the artificial marble as a raw material, to the temporary laminated structure by the chute and the specific gravity and viscosity difference between the slurry By using the natural mixing effect, it is possible to obtain an artificial marble having a distinctive appearance and natural stone realism distinguished from the existing artificial marble.

Claims (12)

There is one background area and two or more color areas with different colors and specific gravity. Artificial marble, characterized in that the difference in specific gravity between the background area and the color gamut 0.01 to 1.0. The artificial marble according to claim 1, wherein the specific gravity difference between the base region and the color region is 0.01 to 0.3. The artificial marble according to claim 1, wherein the specific gravity of the base region is 1.5 to 1.75. The artificial marble according to claim 1, wherein the specific gravity of the color region is larger than that of the background region. (a) preparing a base slurry to be used as the base area; (b) preparing a colored slurry to be used as the color gamut; (c) stacking the base slurry and two or more colored slurry into a chute equipped with a partition to form a layer for each slurry; (d) a method of producing artificial marble comprising the step of partially mixing each slurry naturally bound by the specific gravity and viscosity difference between each slurry after passing through the partition. The method of claim 5, wherein the specific gravity and the viscosity of the slurry are prepared differently by controlling the content of the resin and the filler used in each slurry. The method of claim 5, wherein the viscosity of the base slurry and the colored slurry is the same or the viscosity difference is 90 Poise or less. The method of claim 5, wherein the base slurry has a viscosity of 60 to 120 Poise. The method of claim 5, wherein the viscosity of the colored slurry is lower than the base slurry. The method for producing artificial marble according to claim 5, wherein the specific gravity and the viscosity of each colored slurry are the same. The method of claim 5, wherein the base slurry is introduced into the bottom of the chute, and a colored slurry having a specific gravity higher than that of the base slurry and a viscosity lowered is added to the upper part of the base slurry through a partition. The method of claim 5, wherein the mixed slurry partially mixed in step (d) is fed to a continuously movable steel belt and cured while maintaining at 40 to 60 ° C.

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