KR102645811B1 - Artificial marble and method for manufacturing thereof - Google Patents

Abstract

It contains an acrylic resin and an inorganic filler, and the inorganic filler is contained in an amount of 50 to 175 parts by weight based on 100 parts by weight of the acrylic resin, and the total heat released for 5 minutes by a cone calorimeter according to KS F ISO 5660-1 is Artificial marble weighing less than 8 MJ/㎡ is provided.

Description

Artificial marble and its manufacturing method {ARTIFICIAL MARBLE AND METHOD FOR MANUFACTURING THEREOF}

It relates to artificial marble and its manufacturing method.

Recently, artificial marble is a material that has been in the spotlight as an alternative to natural marble. It has a subtle and soft texture, excellent processability, excellent weather resistance, and excellent durability, so it can be used for a variety of purposes. Due to these physical properties, artificial marble can be used, for example, for various counter tops such as sinks, washbasins, bathtubs, and store reception desks, thresholds, furniture, dining tables, interior and exterior building materials such as interior wall materials, finishing materials, and various interior sculptures.

Some of the above uses require flame retardancy for safety reasons, and its importance is further highlighted due to various recent fire accidents. Accordingly, organic flame retardants can be added to maintain flame retardancy, but there is a problem that substances harmful to the human body are detected in the case of organic flame retardants.

One embodiment of the present invention provides artificial marble that realizes excellent flame retardancy, hardness, and elongation.

Another embodiment of the present invention provides a method for manufacturing the artificial marble.

In one embodiment of the present invention, an acrylic resin and an inorganic filler are included, and the inorganic filler is included in an amount of 50 to 175 parts by weight based on 100 parts by weight of the acrylic resin, and is measured in a cone calorimeter according to KS F ISO 5660-1. We provide artificial marble with a total heat release of 8 MJ/㎡ or less for 5 minutes.

In another embodiment of the present invention, preparing an acrylic resin syrup containing an acrylic resin and an acrylic monomer; Preparing a composition by including an inorganic filler in the acrylic resin syrup; and curing the composition to produce artificial marble, wherein the inorganic filler is included in an amount of 50 to 175 parts by weight based on 100 parts by weight of the acrylic resin, and is measured in a cone calorimeter according to KS F ISO 5660-1. A method for manufacturing artificial marble with a total heat release of 8 MJ/㎡ or less for 5 minutes is provided.

The artificial marble can improve flame retardancy and achieve excellent hardness and elongation without containing excessive amounts of inorganic fillers.

The advantages and features of the present invention and methods for achieving them will become clear with reference to the embodiments described below. However, the present invention is not limited to the embodiments disclosed below and will be implemented in various different forms. These embodiments are provided solely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the present invention of the scope of the invention, and that the present invention is defined by the scope of the claims. It just becomes.

In one embodiment of the present invention, an acrylic resin and an inorganic filler are included, and the inorganic filler is included in an amount of 50 to 175 parts by weight based on 100 parts by weight of the acrylic resin, and is measured in a cone calorimeter according to KS F ISO 5660-1. We provide artificial marble with a total heat release of 8 MJ/㎡ or less for 5 minutes.

Flame retardancy can be improved by adding an organic flame retardant to maintain flame retardancy, or by increasing the amount of inorganic filler that provides flame retardancy per unit volume. However, in the case of organic flame retardants, substances harmful to the human body are detected, and when the content of inorganic fillers is increased, the content of resin contained in artificial marble decreases, resulting in lower elongation and lower formability.

The artificial marble can secure improved flame retardancy without increasing the amount of inorganic filler, and can simultaneously exhibit physical properties such as excellent elongation and hardness.

The artificial marble contains an acrylic resin and an inorganic filler, and the inorganic filler may include one selected from the group consisting of aluminum hydroxide, magnesium hydroxide, calcium carbonate, silica, alumina, and combinations thereof to provide flame retardancy. Specifically, the inorganic filler may be aluminum hydroxide, and causes a dehydrolysis reaction and an endothermic reaction at a temperature of about 200°C to 300°C, thereby improving flame retardancy.

The artificial marble may include the inorganic filler in an amount of about 50 parts by weight to about 175 parts by weight based on 100 parts by weight of the acrylic resin. The artificial marble can maintain the excellent physical properties such as elongation and hardness that acrylic artificial marble generally possesses by containing the above range of inorganic fillers rather than a high content of inorganic fillers.

The inorganic filler may include a first inorganic filler having a diameter of about 1 μm to about 10 μm. Specifically, the inorganic filler may include a first inorganic filler having a diameter of about 1㎛ to about 3㎛.

The artificial marble may include a first inorganic filler having a diameter in the above range, thereby improving flame retardancy by increasing the surface area of the inorganic filler per unit volume compared to the same amount of inorganic filler added. More specifically, the artificial marble includes the first inorganic filler, so that the area of the inorganic filler that receives heat during a fire increases, thereby improving flame retardancy. In addition, the inorganic filler including the first inorganic filler can be densely distributed between the acrylic resins and increase interaction with the acrylic resin to simultaneously improve physical properties such as elongation.

The inorganic filler may further include a second inorganic filler having a diameter of 30㎛ to 100㎛. Specifically, the inorganic filler may further include a second inorganic filler having a diameter of 30㎛ to 60㎛.

The inorganic filler further includes the second inorganic filler in the first inorganic filler, so that flame retardancy can be easily improved without including an excessive amount of inorganic filler, and along with this, it can exhibit excellent hardness and elongation. The diameter of the inorganic filler can be measured using a scanning electron microscope (SEM) after curing the composition containing the inorganic filler and acrylic resin.

The artificial marble includes the first inorganic filler to the second inorganic filler in a weight ratio of about 5:5 to about 9:1, so that it can exhibit not only excellent flame retardancy but also physical properties such as elongation and hardness. For example, if the content of the first inorganic filler is less than the above range, the flame retardancy is reduced, the distribution of the inorganic filler is not dense in relation to the acrylic resin due to a decrease in the surface area of the inorganic filler, and the elongation is reduced. There may be.

The artificial marble containing the acrylic resin and the inorganic filler exhibits excellent flame retardancy, with a total heat release for 5 minutes of about 8 MJ/m2 or less as measured by a cone calorimeter according to KS F ISO 5660-1. If the total amount of heat released exceeds the above range, there may be a problem in securing flame retardancy. Specifically, the artificial marble may have a total heat emission for 5 minutes measured by a cone calorimeter according to KS F ISO 5660-1 of about 5.4 MJ/m2 or less, or about 5.0 MJ/m2 or less, or about 4.4 MJ/m2 or less.

Additionally, the artificial marble may have an elongation of about 15% to about 25% according to Equation 2 below.

[Equation 2]

Elongation (%) = (Lf-Li)/ Li

In Equation 2, Li is the initial length of the artificial marble at 25°C, and Lf represents the length of the artificial marble extended after heating at 180°C for 3 minutes.

The artificial marble may have excellent elongation in the above range by including the above-described inorganic filler. In general, artificial marble breaks easily in areas containing inorganic fillers. Meanwhile, the artificial marble contains an inorganic filler having a diameter in the above-mentioned range, so it is not easily broken and can exhibit excellent elongation in the above-mentioned range.

Since the artificial marble has an elongation within the above range at high temperature, it can achieve an excellent surface appearance without problems of cracks or bursting on the surface even when molded into a three-dimensional shape under high temperature conditions. Specifically, if the elongation is below the above range, problems with thermoformability may occur, causing cracks or bursting. Specifically, the artificial marble may have an elongation of about 15% to about 23.5%.

In addition, the artificial marble may have a Barcall hardness of about 58 or more as measured according to the ISO 19712-2 part 15 standard. Specifically, it may be about 58 to about 78. Since the artificial marble has a Barcol hardness in the above range, problems such as damage during transportation and use of the artificial marble may not occur.

Another embodiment of the present invention includes preparing an acrylic resin syrup containing an acrylic resin and an acrylic monomer; Preparing a composition by including an inorganic filler in the acrylic resin syrup; and curing the composition to produce artificial marble, wherein the inorganic filler is included in an amount of 50 to 175 parts by weight based on 100 parts by weight of the acrylic resin, and is measured in a cone calorimeter according to KS F ISO 5660-1. A method for manufacturing artificial marble with a total heat release of 8 MJ/㎡ or less for 5 minutes is provided.

The above-described artificial marble can be manufactured using the artificial marble manufacturing method. That is, the artificial marble is a cured product of a composition containing acrylic resin syrup and inorganic fillers, and can improve flame retardancy without containing a high content of inorganic fillers, and at the same time exhibit excellent moldability with excellent hardness and excellent high temperature elongation. there is.

First, the method for producing artificial marble includes preparing an acrylic resin syrup containing an acrylic resin and an acrylic monomer.

Specifically, the acrylic resin may have a weight average molecular weight of about 50,000 g/mol to about 150,000 g/mol. If the weight average molecular weight of the acrylic resin is less than the above range, the viscosity of the composition may decrease and flowability may become excessively high, and if it exceeds the above range, the viscosity of the composition may increase, making it difficult to control bubbles or deteriorating moldability.

The melt flow rate (230°C, 3,8kg) (test method ASTM D 1238) of the acrylic resin is about 0.5g/10min to about 10g/10min, or about 2.0g/10min to about 6.0g/10min. It can be. If the melt flow index of the acrylic resin is less than the above range, the melt viscosity increases and fluidity decreases when kneading the acrylic syrup containing the acrylic resin and the inorganic filler, and if it exceeds the above range, the melt viscosity is too low to formability. may deteriorate.

The acrylic monomer consists of alkyl group-containing (meth)acrylate-based monomer, hydroxy-containing (meth)acrylate-based monomer, carboxyl group-containing (meth)acrylate-based monomer, nitrogen-containing (meth)acrylate-based monomer, and combinations thereof. It may include one selected from the group.

The acrylic resin syrup may have a viscosity of about 500 cps to about 3,000 cps or about 800 cps to about 2,000 cps at 25°C. If the viscosity of the acrylic resin syrup is less than the above range, curing properties and shrinkage may be reduced, and if it exceeds the above range, handling of the syrup may become difficult.

And, it includes preparing a composition by including an inorganic filler in the acrylic resin syrup. Additionally, the composition may be prepared by further including additives in addition to the inorganic filler in the acrylic resin syrup and stirring the syrup at about 20 to about 40° C. for about 30 to about 60 minutes. At this time, the viscosity of the composition may be about 1,000 cps to about 10,000 cps, or about 2,000 cps to about 9,000 cps. If the viscosity of the composition is less than the above range, the thickness of the artificial marble may become uneven, and if it exceeds the above range, marks of air bubbles remain in the artificial marble, causing the artificial marble to be easily exposed to contamination or to have an unattractive appearance. It can be. Additionally, the thickness of artificial marble may become uneven.

Details regarding the inorganic filler contained in the composition are as described above.

In addition, the composition may further include one additive selected from the group consisting of a dispersant, coupling agent, crosslinking agent, curing agent, and combinations thereof.

Specifically, the composition may include a dispersant, and the dispersant improves dispersibility by preventing agglomeration of the inorganic filler, especially the first inorganic filler, and increases oil absorption due to an increase in the surface of the inorganic filler, thereby increasing the amount of oil absorbed in the composition. Viscosity stability can be provided by preventing an increase in viscosity. Accordingly, improved flame retardancy can be provided to the artificial marble, which is a cured product of the composition, and physical properties such as elongation and hardness can be prevented from being reduced.

Specifically, the dispersant may be a compound having an alkylene repeating unit of 2 to 15 carbon atoms and a silane group at the terminal. The silane group of the dispersant can easily combine with the inorganic filler, for example, aluminum hydroxide. Accordingly, it is possible to prevent inorganic fillers from agglomerating and settling, and to provide excellent dispersibility. In addition, the alkylene repeating unit having 2 to 15 carbon atoms contained in the compound is not reactive and does not deteriorate the physical properties of artificial marble, and has excellent compatibility with the resin syrup, such as polymethyl methacrylic resin and methyl methacrylic. can indicate. Therefore, the dispersant provides excellent viscosity stability to the composition without deteriorating the physical properties such as flame retardancy, elongation, and hardness of the artificial marble, and can provide uniform and improved flame retardancy throughout the entire artificial marble, which is a cured product of the composition. .

More specifically, the dispersant may have an ether functional group. That is, the dispersant may be a compound that has an alkylene repeating unit of 2 to 15 carbon atoms, is polyether functionalized, and has a silane group at the terminal. The dispersant may be a compound having the ether functional group at the other end. Specifically, the dispersant may be a polyalkylene glycol functionalized silane compound having an alkylene repeating unit having 2 to 15 carbon atoms. For example, the dispersant may be a polyalkylene glycol-functionalized alkoxysilane having an alkylene repeating unit having 2 to 15 carbon atoms. Specifically, the dispersant is polyethylene glycol alkoxysilane, polypropylene glycol alkoxysilane, polybutylene glycol alkoxysilane, polypentylene glycol alkoxy silane, polyhexylene glycol alkoxy silane, polyheptylene glycol. It may be coal alkoxy silane, polyoctylene glycol alkoxy silane, polynonylene glycol alkoxy silane, etc.

The freezing point of the dispersant may be less than about -10°C. Specifically, it may be about -30°C to about -8°C. And, the flash point of the dispersant may exceed about 95°C. Specifically, it may be about 98°C to about 120°C. By having a freezing point and a flash point in the above range, the dispersant does not deteriorate the physical properties of artificial marble, improves the dispersibility of the inorganic filler, further improves compatibility with the resin syrup, and provides excellent flame retardancy. You can.

The dispersant may be included in an amount of about 0.5 to about 10 parts by weight based on 100 parts by weight of the inorganic filler. By including the dispersant within the above range, the composition exhibits uniform and excellent flame retardancy throughout the entire artificial marble, and at the same time can achieve excellent elongation, hardness, and flexural strength of the artificial marble. Specifically, if the content of the dispersant is less than the above range, problems such as reduced viscosity stability of the artificial marble composition and reduced flame retardancy compared to the content of the inorganic filler may occur. And, if it exceeds the above range, problems with flame retardancy and physical properties may become non-uniform.

In addition, the composition includes a coupling agent, which increases the interaction between the inorganic filler densely distributed in the acrylic resin and the acrylic resin, thereby improving physical properties such as elongation and hardness along with flame retardancy.

Specifically, the coupling agent is vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and 3-glycidoxypropyltrimethoxy. Silane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-(meth)acryloxypropylmethyldimethoxysilane, 3-(meth ) Acryloxypropyltrimethoxysilane, 3-(meth)acryloxypropylmethyldiethoxysilane, 3-(meth)acryloxypropyl triethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimeth Toxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3- Aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylidene)propyl amine, N-phenyl-3-aminopropyltrimethoxysilane, N-(vinylbenzyl)- Hydrochloride salt of 2-aminoethyl-3-aminopropyltrimethoxysilane, 3-chloropropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, bis(triethoxysilane) It may include one selected from the group consisting of (silylpropyl) tetrasulfide, 3-isocyanate propyltriethoxysilane, and combinations thereof. For example, the coupling agent is 3-(meth)acryloxypropylmethyldimethoxysilane, 3-(meth)acryloxypropyltrimethoxysilane, 3-(meth)acryloxypropylmethyldiethoxysilane, 3-( It may contain meta)acryloxypropyl triethoxysilane. By having a (meth)acrylic group, the coupling agent can further improve compatibility with the resin syrup. For example, the composition can easily form a crosslinked structure by including a resin syrup containing an acrylic resin and the coupling agent having a (meth)acrylic group. Additionally, the silane group of the coupling agent may be combined with the inorganic filler, for example, aluminum hydroxide. Accordingly, the bond between the organic resin syrup and the inorganic filler can be improved, thereby further improving the dispersibility of the inorganic filler and improving flame retardancy, elongation, and hardness.

The coupling agent may be included in an amount of about 0.5 to about 10 parts by weight based on 100 parts by weight of the inorganic filler. By including the coupling agent in the above range, the composition can exhibit more uniform and excellent flame retardancy throughout the entire artificial marble, and at the same time, achieve excellent elongation and hardness of the artificial marble.

In addition, the composition can further improve high temperature elongation by including a crosslinking agent. Specifically, the crosslinking agent may include one selected from the group consisting of a difunctional (meth)acrylate-based monomer, a difunctional (meth)acrylate-based oligomer, and a combination thereof, and may improve high temperature elongation. Difunctionality may mean the presence of two predetermined groups, for example, acrylate groups, containing a double bond that can form a bond during a curing reaction.

The bifunctional (meth)acrylate monomers include, for example, 1,2-ethylene glycol diacrylate, 1,12-dodethanediol acrylate, 1,4-butanediol di(meth)acrylate, 1,6 -Hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, polyethylene glycol 200 di(meth)acrylate, polyethylene glycol 400 di(meth)acrylate, polyethylene glycol 600 di(meth)acrylate, Neopentylglycol adipate di(meth)acrylate, hydroxyl puivalic acid neopentyl glycol di(meth)acrylate, dicyclopentanyl di(meth)acrylate, caprolactone Modified dicyclopentenyl di(meth)acrylate, ethylene oxide modified di(meth)acrylate, di(meth)acryloxy ethyl isocyanurate, allyl cyclohexyl di(meth)acrylate, tri. Cyclodecane dimethanol (meth)acrylate, dimethylol dicyclopentane di(meth)acrylate, ethylene oxide modified hexahydrophthalic acid di(meth)acrylate, tricyclodecane dimethanol (meth)acrylate, neopentyl glycol Modified trimethylpropane di(meth)acrylate, adamantane di(meth)acrylate, 9,9-bis[4-(2-acryloyloxyethoxy)phenyl]fluorine and these It may include at least one selected from the group consisting of a combination of.

The glass transition temperature of the difunctional (meth)acrylate monomer may be about -25 to about 55°C, or about -10 to about 40°C. By having a glass transition temperature within the above range, high temperature elongation can be sufficiently improved. You can. Accordingly, even if the artificial marble is molded into a three-dimensional shape under high temperature conditions, it can achieve an excellent surface appearance without problems of cracks or bursting on the surface. If the glass transition temperature of the difunctional (meth)acrylate monomer is less than the above range, hardness is lowered and a rubbery feel is felt, and if it is above the above range, bending and post-deformation of the cured product, artificial marble, may occur.

The molecular weight of the difunctional (meth)acrylate-based monomer may be about 330 g/mol to about 1,500 g/mol, or about 500 g/mol to about 1,300 g/mol. If the molecular weight of the difunctional (meth)acrylate monomer is less than the above range, curing shrinkage may increase and problems may occur in that it does not stretch well even when heat is applied, and if it exceeds the above range, bubbles may be generated inside the artificial marble. Problems may arise.

The bifunctional (meth)acrylate-based oligomer is, for example, polymethyl (meth)acrylate oligomer, polyethyl (meth)acrylate oligomer, polypropyl (meth)acrylate oligomer, polymethyldi(meth)acrylate Oligomer, polyethyldi(meth)acrylate oligomer, polydimethyl(meth)acrylate oligomer, polydiethyl(meth)acrylate oligomer, polyethylene glycol di(meth)acrylate oligomer, polyurethane oligomer, and combinations thereof. It may include at least one selected from the group.

The glass transition temperature of the difunctional (meth)acrylate-based oligomer may be about 45°C to about 105°C, or about 45°C to about 90°C. By having a glass transition temperature within the above range, high temperature elongation can be sufficiently improved. You can. Accordingly, the artificial marble can achieve a more excellent surface appearance under high temperature conditions. If the glass transition temperature of the difunctional (meth)acrylate-based oligomer is below the above range, the hardness is lowered and a rubbery feel is felt, and if it is above the above range, bending and post-deformation of the cured product, artificial marble, may occur.

The weight average molecular weight of the difunctional (meth)acrylate-based oligomer may be about 20,000 to about 120,000 g/mol, or about 30,000 to about 110,000 g/mol. If the weight average molecular weight of the difunctional (meth)acrylate-based oligomer is less than the above range, the viscosity is lowered and non-uniformity occurs due to precipitation of inorganic substances, and if it exceeds the above range, it is caused by boiling of the monomer during thermoforming. Internal bubbles are generated.

The crosslinking agent may be included in the composition in an amount of about 0.18% by weight to about 1.7% by weight. Specifically, when a difunctional (meth)acrylate-based monomer is used as the crosslinking agent, it may be included in the composition in an amount of about 0.18% by weight to about 0.7% by weight, and when the difunctional (meth)acrylate-based oligomer is used, It may be included in the composition in an amount of about 0.18% by weight to about 1% by weight. Alternatively, when both the difunctional (meth)acrylate-based monomer and the difunctional (meth)acrylate-based oligomer are used as the crosslinking agent, it may be included in the composition in an amount of about 0.36% by weight to about 1.7% by weight.

By including the difunctional (meth)acrylate-based monomer and/or the difunctional (meth)acrylate-based oligomer in an amount within the above range, the heat curing reaction can be sufficiently progressed and no trace of the difunctional (meth)acrylate-based oligomer is present in the artificial marble manufactured from the composition. The migration phenomenon that occurs due to the presence of reactive monomers can be effectively prevented. For example, if unreacted monomers are present in the composition, over time, yellowing, etc. may occur on the surface of the artificial marble manufactured from the composition, resulting in color difference and deteriorating the quality of the artificial marble. there is.

The composition includes organic peroxides such as benzoyl peroxide, diacyl peroxide such as dicumyl peroxide, butyl hydroperoxide, hydro peroxide such as cumyl hydro peroxide, t-butyl peroxy maleic acid, t-butyl hydro peroxide, t-Butyl hydro peroxybutyrate, acetyl peroxide, lauroyl peroxide, azobisisobutyronitrile, azobisdimethylvaleronitrile, t-butyl peroxy neodecanoate, t-amyl peroxy 2- It may include one polymerization initiator selected from the group consisting of ethyl hexanoate, and combinations thereof.

The artificial marble may have a viscosity change of about 2,000 cps or less according to Equation 1 below. For example, the viscosity change amount may be about 0 to about 2,000 cps, or about 100 cps to about 2,000 cps.

[Equation 1]

Viscosity change (△V, cps) = (Vf-Vi)

In Equation 1, Vi is the initial viscosity of the composition at 25°C, and Vf is the viscosity of the composition after 2 hours at 25°C. At this time, the initial viscosity refers to the viscosity of the composition after stirring.

The artificial marble is a thermosetting product of the composition, and has a low viscosity change in the above range, so that it can exhibit uniform flame retardancy, elongation, and hardness throughout the entire artificial marble. Specifically, when the viscosity change exceeds the above range, the difference in the total amount of heat released between the surface and back of the artificial marble increases, making it difficult to secure flame retardancy, and there may be a problem of warping of the artificial marble.

Additionally, the method for producing artificial marble includes curing the composition to produce artificial marble. The artificial marble may be manufactured by heat curing at about 75°C to about 95°C, or about 80°C to about 90°C. If the curing temperature is below the above range, the content of residual monomers that have not been cured may increase, causing yellowing and deteriorating the quality of artificial marble. In addition, if the curing temperature exceeds the above range, boiling of the composition may occur during marble production, leaving bubble marks, and phenomena such as warping of artificial marble may occur. The artificial marble may be cured for about 20 minutes to about 60 minutes.

Below, specific embodiments of the present invention are presented. However, the examples described below are only for illustrating or explaining the present invention in detail, and the present invention should not be limited thereto.

<Examples and Comparative Examples>

Example 1:

Acrylic resin syrup (25°C, viscosity 1000 cps) was prepared by stirring 28% by weight of polymethyl methacrylate (LG Chemical, IH830) and 72% by weight of methyl methacrylate at 60°C for 30 minutes.

In addition, 100 parts by weight of the acrylic resin syrup contains aluminum hydroxide, 1 part by weight of polyethylene glycol alkoxysilane with a freezing point of less than about -10°C and a flash point of more than about 95°C, and 3-(meth)acryloxypropyltrimethoxysilane. A composition containing 1 part by weight and 1 part by weight of polyethylene glycol di(meth)acrylate oligomer having a glass transition temperature of 45°C to 55°C and a weight average molecular weight of 53,000, stirred at 30°C for 40 minutes (viscosity: 5000 cps, 25°C) ℃) was prepared. Afterwards, the composition was put into a mold and cured at 80°C for 30 minutes to prepare artificial marble.

At this time, the artificial marble contains aluminum hydroxide in an amount of 175 parts by weight relative to 100 parts by weight of the acrylic resin, and the aluminum hydroxide is first aluminum hydroxide having a diameter of 1㎛ to 3㎛ and a diameter of 30㎛ to 60㎛. Secondary aluminum hydroxide was included in a weight ratio of 5:5.

Example 2:

By adjusting the content of the first aluminum hydroxide having a diameter of 1㎛ to 3㎛ and the second aluminum hydroxide having a diameter of 30㎛ to 60㎛ contained in the composition, the artificial marble having a diameter of 1㎛ to 3㎛ Artificial marble was manufactured in the same manner as in Example 1, except that first aluminum hydroxide and second aluminum hydroxide having a diameter of 30㎛ to 60㎛ were included in a weight ratio of 7:3.

Example 3:

By adjusting the content of the first aluminum hydroxide having a diameter of 1㎛ to 3㎛ and the second aluminum hydroxide having a diameter of 30㎛ to 60㎛ contained in the composition, the artificial marble having a diameter of 1㎛ to 3㎛ Artificial marble was manufactured in the same manner as in Example 1, except that first aluminum hydroxide and second aluminum hydroxide having a diameter of 30㎛ to 60㎛ were included in a weight ratio of 9:1.

Comparative Example 1:

By adjusting the content of the first aluminum hydroxide having a diameter of 1㎛ to 3㎛ and the second aluminum hydroxide having a diameter of 30㎛ to 60㎛ contained in the composition, the artificial marble having a diameter of 1㎛ to 3㎛ Artificial marble was manufactured in the same manner as in Example 1, except that first aluminum hydroxide and second aluminum hydroxide having a diameter of 30㎛ to 60㎛ were included in a weight ratio of 3:7.

<Evaluation>

Experimental Example 1: Viscosity stability

The amount of change in viscosity of the compositions prepared in the examples and comparative examples was measured according to Equation 1 below.

[Equation 1]

Viscosity change (△V, cps) = (Vf-Vi)

In Equation 1, Vi is the initial viscosity of the composition at 25°C, and Vf is the viscosity of the composition after 2 hours at 25°C. At this time, the initial viscosity refers to the viscosity of the composition after stirring.

At this time, if the viscosity change was less than 2,000 cps, it was indicated as “OK”, and if it exceeded 2,000 cps, it was indicated as “NG.”

viscosity stability Example 1 OK Example 2 OK Example 3 OK Comparative Example 1 OK

Experimental Example 2: Flame retardancy

Each artificial marble manufactured in the above examples and comparative examples was produced into specimens measuring 100 mm (L) 100 mm (W) 12 mm (T) using a CNC engraving machine (TinyCNC-6012).

Then, using a cone calorimeter (Festek International) according to the measurement conditions of KS F ISO 5660-1, 50 kW radiant heat was applied to the specimen for 5 minutes and the total heat released (THR) was measured. And the results are listed in Table 2 below.

Experimental Example 3: Elongation

Each artificial marble manufactured in the above examples and comparative examples was produced into specimens measuring 120 mm (L) 10 mm (W) 1.5 mm (T) using a CNC engraving machine (TinyCNC-6012).

For each of the specimens, the high temperature elongation at 180°C was measured using UTM testing equipment (Universal Testing Machine). Specifically, after mounting the prepared specimen on Instron 8872, the chamber is closed and heated at 180°C for 3 minutes. Afterwards, using UTM, the rolling speed was set to 100 mm/min, the distance between grips was set to 100 mm, and the specimen was pulled to measure the extended length of the specimen. And, the high temperature elongation results according to Equation 2 below are shown in Table 2 below.

[Equation 2]

Elongation (%) = (Lf-Li)/ Li

In Equation 2, Li is the initial length of the specimen at 25°C, and Lf means the extended length of the specimen heated at 180°C.

Cone calorimeter (MJ/㎡) Elongation (%) Example 1 5.4 23.2 Example 2 5.0 21.8 Example 3 4.4 20.1 Comparative Example 1 10.3 9.12

As shown in Table 2, the Example simultaneously realizes excellent flame retardancy and elongation, while Comparative Example 1 shows that both flame retardancy and elongation are significantly poor.

Claims (12)

Contains acrylic resin and inorganic filler,
The inorganic filler is included in an amount of 50 to 175 parts by weight based on 100 parts by weight of the acrylic resin,
The inorganic filler includes a first inorganic filler having a diameter of 1㎛ to 3㎛ and a second inorganic filler having a diameter of 30㎛ to 60㎛,
The weight ratio of the first inorganic filler to the second inorganic filler is 5:5 to 9:1,
The total heat released for 5 minutes by a cone calorimeter according to KS F ISO 5660-1 is 8 MJ/㎡ or less,
According to Equation 2 below, the elongation is 15% to 25%
Artificial Marble:

[Equation 2]
Elongation (%) = (Lf-Li)/ Li
In Equation 2, Li is the initial length of the artificial marble, and Lf refers to the length of the artificial marble stretched after heating at 180° C. for 3 minutes.
According to paragraph 1,
The total heat released for 5 minutes by a cone calorimeter according to KS F ISO 5660-1 is 5.4 MJ/㎡ or less.
Artificial marble.
According to paragraph 1,
The total heat released for 5 minutes by a cone calorimeter according to KS F ISO 5660-1 is 5.0 MJ/㎡ or less.
Artificial marble. According to paragraph 1,
The total heat released for 5 minutes by a cone calorimeter according to KS F ISO 5660-1 is 4.4 MJ/㎡ or less.
Artificial marble.
According to paragraph 1,
The artificial marble has a Barcall hardness of 58 to 78 measured according to ISO 19712-2 part 15 standard.
Artificial marble.
According to paragraph 1,
The artificial marble is a cured product of a composition further comprising a crosslinking agent along with the acrylic resin and the inorganic filler,
The crosslinking agent includes one selected from the group consisting of difunctional (meth)acrylate-based monomers, difunctional (meth)acrylate-based oligomers, and combinations thereof.
Artificial marble.
According to clause 6,
The glass transition temperature of the difunctional (meth)acrylate monomer is -25 to 55°C,
The glass transition temperature of the bifunctional (meth)acrylate-based oligomer is 45°C to 105°C.
Artificial marble.
According to clause 6,
The molecular weight of the difunctional (meth)acrylate monomer is 330 g/mol to 1,500 g/mol,
The weight average molecular weight of the bifunctional (meth)acrylate-based oligomer is 20,000 g/mol to 120,000 g/mol.
Artificial marble.
delete delete According to paragraph 1,
According to Equation 2 above, the elongation is 15% to 23.5%
Artificial marble.
Preparing an acrylic resin syrup containing an acrylic resin and an acrylic monomer;
Preparing a composition by including an inorganic filler in the acrylic resin syrup; and
Comprising: curing the composition to produce artificial marble,
The inorganic filler is included in an amount of 50 to 175 parts by weight based on 100 parts by weight of the acrylic resin,
The inorganic filler includes a first inorganic filler having a diameter of 1㎛ to 3㎛ and a second inorganic filler having a diameter of 30㎛ to 60㎛,
The weight ratio of the first inorganic filler to the second inorganic filler is 5:5 to 9:1,
The total heat released by the artificial marble for 5 minutes according to a cone calorimeter according to KS F ISO 5660-1 is 8 MJ/㎡ or less,
According to Equation 2 below, the elongation of the artificial marble is 15% to 25%.
Manufacturing method of artificial marble:

[Equation 2]
Elongation (%) = (Lf-Li)/ Li
In Equation 2, Li is the initial length of the artificial marble, and Lf refers to the length of the artificial marble stretched after heating at 180° C. for 3 minutes.