Composition for artificial marble
A composition for artificial marble, of the present invention comprises: a binder resin; an inorganic filler excluding zinc oxide; and zinc oxide, wherein the zinc oxide has a size ratio (B/A), in which peak A is a 370 nm to 390 nm region and peak B is a 450 nm to 600 nm region, of approximately 0.01 to 1 during photoluminescence measurement, and has a BET surface area of approximately 10 m 2 /g or less.
1. A composition for artificial marble, comprising:
a binder resin;
inorganic fillers excluding zinc oxide; and
zinc oxide;
wherein the zinc oxide has a peak intensity ratio (B/A) of about 0.01 to about 1, where A indicates a peak in the wavelength range of 370 nm to 390 nm and B indicates a peak in the wavelength range of 450 nm to 600 nm in photoluminescence measurement, a BET surface area of about 10 m 2 /g or less, as measured using a BET analyzer, a peak position degree (2θ) in the range of about 35° to about 37°, and a crystallite size of about 1,000 Å to about 2,000 Å in X-ray diffraction (XRD) analysis, as calculated according to Equation 1:
Crystallite
size
(
D
)
=
K
λ
βcos
θ
,
[
Equation
1
]
where K is a shape factor, λ is an X-ray wavelength, β is an FWHM value (degree) of an X-ray diffraction peak, and θ is a peak position degree.
2. The composition for artificial marble according to claim 1 , comprising:
100 parts by weight of the binder resin;
about 100 parts by weight to about 300 parts by weight of the inorganic fillers excluding zinc oxide; and
about 1 part by weight to about 10 parts by weight of the zinc oxide.
3. The composition for artificial marble according to claim 1 , wherein the binder resin comprises an acrylic resin and/or an unsaturated polyester resin.
4. The composition for artificial marble according to claim 1 , wherein the binder resin is a mixture of poly(meth)acrylate and a (meth)acrylate monomer.
5. The composition for artificial marble according to claim 1 , wherein the inorganic fillers comprise silica, alumina, calcium carbonate, calcium hydroxide, aluminum hydroxide, magnesium hydroxide, pearlite, vermiculite, smectite, and/or bentonite.
6. The composition for artificial marble according to claim 1 , wherein the zinc oxide has an average particle diameter of about 0.5 μm to about 3 μm.
7. The composition for artificial marble according to claim 1 , wherein the inorganic fillers have a greater average particle diameter than the zinc oxide.
8. The composition for artificial marble according to claim 1 , wherein an average particle diameter ratio of the inorganic fillers to the zinc oxide ranges from about 0.3:1 to about 200:1.
9. The composition for artificial marble according to claim 1 , further comprising:
marble chips, a crosslinking agent, a crosslinking accelerator, a curing agent, a curing accelerator, a polymerization initiator, an antifoaming agent, a dispersant, a coupling agent, and/or a pigment.
10. The composition for artificial marble according to claim 1 , wherein the composition has a color variation (ΔE) of about 0 to about 3, as calculated according to Equation 2 based on initial color values (L 0 *, a 0 *, b 0 *) measured on an injection-molded specimen having a size of 50 mmx 90 mmx 3 mm using a colorimeter and color values (L 1 *, a 1 *, b 1 *) of the specimen measured using the colorimeter after weather resistance testing for 3,000 hours in accordance with SAE J 1960:
Color variation (Δ E )=√{square root over ((Δ L *) 2 (Δ a *) 2 +(Δ b *) 2 )}, <Equation 2>
where ΔL* is a difference (L 1 *−L 0 *) between L* values before and after temperature/humidity testing, Δa* is a difference (a 1 *−a 0 *) between a* values before and after temperature/humidity testing, and Δb* is a difference (b 1 *−b 0 *) between b* values before and after temperature/humidity testing.
11. The composition for artificial marble according to claim 1 , wherein the composition has an antibacterial activity against Staphylococcus aureus of about 2.0 to about 7.0 and an antibacterial activity against Escherichia coli of about 2.0 to about 6.5, as measured on 5 cm×5 cm specimens inoculated with Staphylococcus aureus and Escherichia coli , respectively, in accordance with JIS Z 2801 and calculated according to Equation 3:
Antibacterial activity=log( M 1 /M 2), [Equation 3]
where M1 is the number of bacteria as measured on a blank specimen after incubation under conditions of 35° C. and 90% RH for 24 hours and M2 is the number of bacteria as measured on a specimen of the artificial marble after incubation under conditions of 35° C. and 90% RH for 24 hours.
12. Artificial marble formed of the composition for artificial marble according to claim 1 .