FUNCTIONAL UV PAINT, CONSTRUCTION MATERIAL USING THE SAME, AND METHOD OF PREPARING THE

PAINT

Technical Field

[1] The present invention relates to a functional UV paint, and more particularly, to a UV paint which includes a dry plant powder or the like instead of either an additive or a loading pigment among constituents of a UV curable paint to reduce a variety of volatile organic compounds (VOCs) and remove formaldehyde (HCHO), thereby providing an environmental friendly paint composition, and to minimize the amount of dissipation of hazardous compounds resulting from construction materialsto which the paint is applied, thereby improving indoor air quality of human residences, a construction material using the same, and a method of preparing the paint.

Background Art

[2] Among various contaminants affecting indoor air quality, VOCs and HCHO have an effect on the nervous system as well respiratory organs and circulatory organs of humans, therebyreducing the sensibility of the peripheral nervous system and have cancer-causing ability and toxicity as shown in Table 1 (VOCs generated indoors and effects thereof) and Table 2 ( HCHO hazards). Thus, these materials are regulated in Korea, The United States, Japan, Europe, etc.

[3] Table 1

[4] Table 2

[5] Hitherto, a paint prepared by mixing TiO (photocatalyst), tourmaline (inorganic material), anion, ZnO-MnO (new material), etc. with a synthetic resin has been used to improve indoor air quality or air handling unitshave been installed in residential or commercial buildings to improve indoor air quality. However, these methods do not have high effectiveness due to high costs and non-proven effects.

[6] In addition, efficiency of decomposing or adsorbing VOCs and HCHO diminishes with time.

[7] Meanwhile, polyphenol compounds, flavonoid compounds and steroid compounds obtained naturally are known to have many functions including deodorization, detoxification on heavy metals and nicotine, antitumor effects, suppression of environmental hormones, antioxidation, decomposing nitrous salt, sterilization of catechin components and so on. These compounds are currently used to prepare beverages, cosmetics, and various foods having the above-described functions.

[8] Paints including natural materials such as wood powder, chaff powder and rice- straw powder are disclosed in Korean Patent Laid-Open Publication Nos. 2002-46395, 2003-26710, and 2003-72152. However, the gist of these patents is providing texture, far-infrared ray radiation function, etc. to the paints and there is no consideration of VOCs and HCHO.

[9] Furthermore, the paints are aqueous paints. Thus, a UV curable paint of the present invention is fundamentally different from conventional paints in view of technical application and material constitution. For example, while UV curable paints do not contain adhesives and essentially contain a photoinitiator to be cured by UV light, conventional paints essentially contain an adhesive and do not contain a UV inhibitor.

[10] In this regard, a UV paint is required to minimize VOCs and HCHO of the paint itself, not to affect workability in the painting application and physical properties of paint film, and to remove VOCs of products using the UV paint.

[11] Thus, there is demand for a new functional UV paint capable of meeting the above- described requirements. Disclosure of Invention

Technical Solution

[12] The present invention provides an environmental friendly, functional UV paint which can minimize the amount of dissipation of VOCs and HCHO of the paint itself

and products using the paint, without affecting workability and physical properties of paint film. [13] The present invention also provides a construction material using the functional

UV paint.

[14] The present invention also provides a method of preparing the functional UV paint.

[15] According to an aspect of the present invention, there is provided a functional UV paint including a polyphenol compound, a flavonoid compound, a steroid compound, or a mixture thereof, in which molecular weights of the compounds range from 250 to

1000. [16] In the UV paint, the flavonoid compound or the polyphenol compound may be at least one compound selected from the group consisting of anthoxanthins, anthocyanins, catechins, tannin, and caffeine.

[17] In the UV paint, the steroid compound may be cholesterol, saponin, or β -carotene.

[18] In the UV paint, the flavonoid compound, the polyphenol compound, or the steroid compound may be included in an amount of 0.01 to 2 wt% based on the total weight of the paint. [19] In the UV paint, the flavonoid compound or the steroid compound may be obtained from anatural plant. [20] In the UV paint, the natural plant may be oak, mangrove, mahogany, acacia, persimmon tree, chestnut shell, peach, apple, graph, persimmon, green tea, black tea, oolong tea, Jasmin tea, Wuyi tea, Tie-Guang-Yin tea, Bongro tea, Youbi tea, Soosun tea, Ogo tea, white tea, blue tea, powdered green tea, Gyeolmyeongja tea, or tobacco leaves. [21] In the UV paint, the flavonoid compound, the polyphenol compound, or steroid compound may be in the form of dry plant powder, plant flakes, plant extracts or a dispersion of the powder. [22] In the UV paint, the dry plant powder or plant flakes may have a size of 0.02 to 125

D . [23] In the UV paint, the dry plant powder or plant flakes may be added in an amount of

1 to 5 wt% based on the total weight of the paint. [24] In the UV paint, the dry plant powder or plant flakes may be added in an amount of

1 to 2.5 wt% based on the total weight of the paint. [25] In the UV paint, a solvent used in the extract or the dispersion may be water, alcohol, oil, or resin. [26] The UV paint may be used to paint a surface of a material such as a door, a window, a chair, a desk, a floor, a wall paper, a floor covering, a ceiling material, interior and exterior of automobiles, a wardrobe, a television, a refrigerator, a kimchi refrigerator, home appliance, a wall closet material or a flooring material

[27] According to another aspect of the present invention, there is provided a construction material painted with the UV paint.

[28] According to another aspect of the present invention, there is provided a method of preparing the UV paint, the method including: screening particulates with a particle size of 0.02 to 125 D after pulverizing dry plant; sufficiently mixing paint raw materials including an oligomer; and adding and dispersing into the mixed paint raw materials the particulates in an amount of 1 to 5 wt% based on the total weight of the paint.

[29] In the method, a liquid extract of plant or a dispersion of the particulates may be added to the paint raw materials instead of the particulates.

[30] The functional UV paint includes a natural compound having adsorptive power, unlike a conventional UV paint, to reduce VOCs of products using the paint as well as VOCs and HCHO of the paint itself.

Advantageous Effects

[31] The functional UV paint according to an embodiment of the present invention can reduce VOCs of a product using the same as well as VOCs and HCHO of the paint itself.

Description of Drawings

[32] The above and other features and advantages of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which:

[33] FIG. 1 is a flowchart illustrating a process of preparing a UV paint which contains dry plant powder or plant flake powder, according to an embodiment of the present invention;

[34] FIGS. 2A through 2C are photographic images of construction materials coated with the UV paint;

[35] FIGS. 3A through 3C are photographic images showing water and discoloration resistance of construction materials coated with the UV paint; and

[36] FIG. 3D illustrates brightness of construction materials coated with the UV paint.

Mode for Invention

[37] Hereinafter, the present invention will be described in greater detail.

[38] The present invention provides a functional UV paint including a flavonoid compound, a polyphenol compound, a steroid compound, or a mixture thereof, in which molecular weights of the compounds range from 250 to 1000.

[39] The flavonoid compound which is an amber pigment widely distributed in plants is derived from flavus that means amber color in Greek and refers to a plant pigment having flavone as a basic structure. A relatively low amount of the flavonoid compound is contained in animals and the flavanoid compound is abundant in leaves,

flowers, roots, fruits, and stems of plants.

[40] The polyphenol compound is a chemical distributed in specific plants that taste astringent and bitter and has a structure of an aromatic compound such as benzene having at least one hydroxyl group (-OH). The polyphenol compound is widely known to have pharmacological functions such as antibiotic and anti-inflammatory effects, skin smoothing, lowering of cholesterol, and anti-allergic effects.

[41] The steroid compound having a steroid nuclei is generally contained in hormones.

However, the steroid compound can have various structures according to substituents thereof and also exist in plants.

[42] Among these compounds, compounds having a molecular weight of 250 to 1000 can be used in the present invention. When the molecular weight is less than 250, volatibility is undesirably high. When the molecular weight is greater than 1000, an oligomer is formed, which increases viscosity of added materials or relatively reduces absorptive power to organic materials.

[43] The flavonoid compound or the polyphenol compound used in the present invention is not particularly restricted, but is preferably antoxanthins, anthocyanins, catechins, or Tannin, in particular catechins or Tannin.

[44] Catechins have a structure represented by Formula 1 ((-)-catechin) and a structure represented by Formula 2 ((+)-catechin) and many derivatives based on such structures are known.

[45] Formula 1

[47] Also, catechins are functional compounds known to have various pharmacological effects. [48] The steroid compound useful in the present invention is not particularly restricted, but is preferably cholesterol, saponin and so on, in particular saponin. [49] Saponin can have structures having a saccharide attached to steroid nuclei (aglycone), for example, structures represented by Formulae 3 and 4. Examples of the saccharide include D-glucose, D-galactose, L-arabinose, and D-rhamnose.

[50] Formula 3

[51] Formula 4

Glucose^ rhamnose rhamnose

[52] The flavonoid compound, the polyphenol compound, or the steroid compound may be included in an amount of 0.01 to 2 wt% based on the total weight of the paint. When the amount of the compound is less than 0.01 wt%, it is difficult to adsorb VOCs etc. When the amount of the compound is greater than 2 wt%, the obtained effects are insignificant in spite of an increase in the added amount and products using the paint are discolorized due to inherent color of the compound.

[53] The flavonoid compound, the polyphenol compound, or the steroid compound used in the present invention may be obtained from a natural plant. The plant is not particularly restricted as long as it contains the above-described compounds. Examples of

the plant include oak, mangrove, mahogany, acacia, persimmon tree, chestnut shell, peach, apple, graph, persimmon, green tea, black tea, oolong tea, Jasmin tea, Wuyi tea (?), Tie-Guang-Yin tea, Bongro tea, Youbi tea, Soosun tea, Ogo tea, white tea, blue tea, powdered green tea, Gyeolmyeongja tea, and tobacco leaves. The flavonoid compound, the polyphenol compound, or the steroid compound are not particularly restricted in form thereof, but may be in the form of dry plant powder, plant flakes, or plant extracts or a dispersion of the powder.

[54] An exemplary embodiment of the UV paint using green teawill now be described in greater detail.

[55] Main ingredients of green tea are catechin (10-18%), other flavonoids (0.6-0.7%), caffeine (2-4%), polysaccharide (0.6%), Vitamin C (150-250 mg%), Vitamin E (25-70 mg%), β -carotene (13-29 mg%), GABA ( γ -aminobutyric acid) (100-200 mg%), saponin, fluorine (90-350 ppm), zinc (35-75 ppm), and selenium (1.0-1.8 ppm). Catechin that is most abundant in green tea has many hydroxyl groups (-OH) in its chemical structure. Thus, catechin can easily bind with VOCs to be stabilized. In this regard, catechin has an antioxidation effect of removing active oxygen in body and facilitates oxidation of fat together with vitamins. In addition, cathechin chemically adsorbs HCHO at ortho- and para-portions of a polyphenol group. Most reactions in the polyphenol group are exothermic reactions, and thus once chemical bonding occurs, the bonding has a strong binding force. Thus, materials that have undergone chemical reactions are not re-discharged. Saponin binds with stearin, alcohol, phenol and so on to form a poorly soluble molecular compound. Green tea powder catches VOCs and HCHO in thesame principle that the ingredients of the green teareact with various organic compounds in thehuman body.

[56] An extract of green tea or green tea flake is obtained in a liquid phase by extracting green tea or green tea flake using water or an organic solvent such as alcohol. A total volatile organic compound (TVOC) refers to allvolatile organic compounds detected- betweenhexane and hexadecane during a GC/MS analysis under ISO 6000-3 and 6000-6.

[57] Meanwhile, the size of the dry plant powder or plant flakes may be 0.02 to 125 D .

When the size of the dry plant powder or plant flakesis less than 0.02 D , it is difficult to mix and compound with paint due to dust. When the size of the dry plant powder or plant flakes is greater than 125 D , it is difficult to uniformly disperse it when mixing with paint. The amount of the dry plant powder or plant flakes is preferably 1 to 5 wt%, for example, and more preferably 1 to 2.5 wt%, based on the total weight of the paint. When the amount of the dry plant powder or plant flakes is less than 1 wt%, it is difficult to obtain desired effects due to a low amount of effective ingredients in the powder. When the amount of the dry plant powder or plant flakes is greater than 5

wt%, the obtained effects are insignificant in spite of an increase in the added amount and the color of the paint may deteriorate due to inherent color of the powder.

[58] The solvent used in the preparation of the plant extract and the dispersion of the powder may be any solvent used in the extraction of organic materials, but may be water such as tap water, distilled water, and ultrapure water; alcohols such as methanol, ethanol, propanol, butanol, isopropylalcohol, and hexanol; oils such as drying oils, for example, linseed oil, wood oil, and perilla oil; resins such as acryl, epoxy, urethane, ester, silica, melamine, phenol, and urea resins, etc.

[59] The UV paint of the present embodiment is not particularly restricted in its application, but may be used to paint a surface of doors, windows, chairs, desks, floors, wall paper, a floor covering, ceiling material, wall closet material, and flooring material, interior and exterior of automobiles, televisions, refrigerators, kimchi refrigerators, and home appliance.

[60] The present invention also provides a construction material painted with the UV paint. The construction material is not particularly restricted, but may be a ceiling material, a wall closet material, or a flooring material, for example, a heated floor, a floor coveringor a tile.

[61] The UV curable paint containing a green tea component can be used as a paint in order to improve air quality of rooms or underground space. Furthermore, the UV curable paint can be used in the painting of ceilings, floors, and walls, to minimize VOCs and HCHO.

[62] A method of preparing the UV paint according to an embodiment of the present invention will now be described in detail.

[63] FIG. 1 is a flowchart illustrating a process of preparing a UV paint which contains dryplantpowder orplantflake powder, according to an embodiment of the present invention. The method of preparing the UV paint includes: screening particulates with a particle size of 0.02 to 125 D after pulverizing a dry plant; sufficiently mixing paint raw materials including an oligomer; and adding and dispersing into the mixed paint raw materials the particulates in an amount of 1 to 5 wt% based on the total weight of the paint. FIG. 1 is a diagram of a process of preparing a UV paint, which contains dry plant powder or plant flake powder. The preparation process includes processing of particulates, mixing of paint raw materials, compounding, adjusting, and inspecting.

[64] In the processing of particulates, green tea leaves or stems are pulverized at highro- tatoryspeed using a pulverizer. After the pulverization is completed, air and pulverized particulates discharged from the pulverizer are classified by particle size using an air blower and only particulates with a particle size of 0.02 to 125 D are selected and used.

[65] In the method, a liquid extract of plant or a dispersion of the particulates may be added to the paint raw materials instead of the particulates. The powder can be added

to paint raw materials, but can be extracted with an organic solvent to form a liquid extract or can be dissolved or dispersed in a solvent.

[66] The mixing of paint raw materials is to sufficiently mix an oligomer and a monomer which are main raw materials of the UV curable paint before compounding the green tea powder.

[67] Generally used UV paints are divided into solvent-free UV paints and solvent- based UV paints, and main constituents thereof are as described in Table 3. [68] Table 3

[69] The additives in the UV paints are materials added in the development of functional products and examples thereof include a leveling agent, an antifoaming agent, a polymerization inhibitor, a dispersant, and an anti-precipitation agent. For example, when a fluorine resin is added, contamination resistance increases, when a special silicone component is added, hardness increases, and when elvan is added, far infrared raysare emitted.

[70] When the dry plant powder or plant flake powder is used as an additive, a functional paint that has reduced VOCs and catches HCHO can be provided. Also, when the dry plant powder or plant flake powder is used instead of talc or CaCO , which is an extender pigment, the content of the dry plant powder in the UV paint increases, which can more effectively reduce VOCs and remove HCHO.

[71] In the compounding process, an oligomer, a monomer and a photoinitiator, which are main ingredients, are mixed and compounded with an antifoaming agent, an extender pigment and an additive, which are subsidiary ingredients. In the present invention, a well-prepared dry plant powder or plant flake powder is added instead of the extender pigment or the additive and thoroughly dispersed.

[72] The amount of the dry plant powder or plant flake powder is such that the paint has

a proper viscosity to maintain the workability of a conventional UV paint and is not discolorized. Thus, the amount of the dry plant powder or plant flake powder is 5 wt% or less based on the total weight of the paint. Although the dry plant powder or plant flake powder can be added up to 10 wt%, the paint losesits basic color and is col- orizedaccording to the color of the plant.

[73] The particle size of the dry plant powder or plant flake powder should be 125 D or less, for example, 100 D or less not to affect dispersion of the UV paint, formation and shape of paint film. When the particle size is greater than 125 D , the dry plant powder is agglomerated and precipitated. When a paint containing such a powder is applied to a product, uniform painting is difficult and workability is poor.

[74] To improve the dispersibility of the dry plant powder or plant flake powder in the

UV paint, the dry plant powder or plant flake powder may be mixed with an oligomer after being dissolved or dispersed in drying oils such as linseed oil, wood oil, and perilla oil; water; alcohols such as methanol, ethanol, propanol, butanol, iso- propylalcohol, and hexanol; and synthetic resins such as acryl, epoxy, urethane, and ester resins.

[75] Viscosity or gloss of the UV paintneeds to be adjusted according to the use of the

UV paint.

[76] In the inspecting process, it is judged whether the UV paint meets standard requirements, and standardization and product applicability tests are performed. Through this process, the UV paint containing a green tea component is finally obtained.

[77] Examples

[78] Preparation of UV curable paint

[79] Example 1

[80] Green tea leaveswere pulverized at high rotary speedusing a pulverizer. Only particulates with a particle size of 0.02 to 125 D were screened among particulates classified by an air blower. After paint raw materials were sufficiently mixed, the green tea powder was added to the paint raw materials having contents as in Table 4 and dispersed to obtain a UV paint. In Table 4, urethane acrylate and epoxy acrylate were used as oligomers (60 wt%), a styrene monomer or an acrylate monomer including diphenaethrylo hexaacrylate was used as a monomer (25 wt%), and a pho- toinitiator having two or more functional moiety (4 wt%), an additive (1 wt%) and an extender pigment (8 wt%) were used. The paint raw material was AULEX 893FK-HV and No050404 green tea (2 wt%) was added.

[81] Table 4

[82] Example 2

[83] A UV paint was prepared in the same manner as in Example 1, except that 7 wt% of the extender pigment and 2.5 wt% of green tea powder were used. [84] Example 3

[85] A UV paint was prepared in the same manner as in Example 1, except that 7 wt% of the extender pigment and 3 wt% of green tea powder were used. [86] Example 4

[87] A UV paint was prepared in the same manner as in Example 1, except that 5 wt% of the extender pigment and 5 wt% of green tea powder were used. [88] Comparative Example 1

[89] A UV paint was prepared in the same manner as in Example 1, except that 10 wt% of the extender pigment was used and no green tea powder was added. [90] Comparative Example 2

[91] A UV paint was prepared in the same manner as in Example 1, except that 0.1 wt% of green tea powder and 9.9 wt% of the extender pigment were used. [92] Comparative Example 3

[93] A UV paint was prepared in the same manner as in Example 1, except that 9 wt% of green tea powder and 1 wt% of the extender pigment were used. [94] Comparative Example 4

[95] A UV paint was prepared in the same manner as in Example 1, except that 5 wt% of the extender pigment and 5 wt% of Angelica Keiskei Koidz were used instead of green tea powder.

[96] Comparative Example 5

[97] A UV paint was prepared in the same manner as in Example 1, except that 5 wt% of the extender pigment and 5 wt% of cale were used instead of green tea powder. [98] Experimental Example

[99] Measurement of TVOC concentration and dissipation rate of the UV paints

[100] 1.2 g of each of the UV paints prepared in Examples 1-4 and Comparative

Examples 1-5 was applied to a 16.5 cm x 16.5 cm glass in an area of 6.32 cm x 6.32 cm. The glass was irradiated with 212 mj/cm UV lamp at a line speed of 10 m/min.

The amount of dissipation and the dissipation rate of TVOC of the UV paints were measured using Small Chamber and FLEC (field and laboratory emission cell). The obtained results are set forth in Table 5. [101] Table 5

[102] Measurement of TVOC dissipation rate of construction material using the UV paint [103] The UV paints prepared in Examples 1-4 and Comparative Examples 1-5 were painted on a flooring material (arboretum heated floor, produced by LG Chem. Ltd.).

The dissipation rate of TVOC was measured using Small Chamber. The obtained results are set forth in Table 6.

[104] Table 6

[105] As shown in Table 5, the concentration and the TVOC dissipation rate of UV paints prepared in Examples 1-4 is about 1/3 of that of Comparative Example 1. Comparative Examples 4 and 5, in which Angelica Keiskei Koidz and cale are used instead of green tea powder, exhibit high TVOC concentration and dissipation rate. Also, Comparative Examples 2 and 3 have higher TVOC concentration and dissipation rate than Examples 1-4. These results indicate that the concentration range of the green tea powder of Examples 1-4 is the most suitable for reducing the TVOC concentration

and the dissipation rate. Thus, it is confirmed that compounds obtained from natural plants used in the present invention can effectively reduce TVOC. As shown in Table 6, the UV paint of the present invention also reduces the TVOC dissipation rate even when applied to a construction material. Thus, the construction material using the UV paint of the present invention can act as a barrier against hazardous compounds unlike conventional construction materials.

[106] Appearance evaluation for construction material using the UV paint

[107] The appearance of the flooring material (arboretum heated floor) used in the measurement of the TVOC dissipation rate was evaluated.

[108] FIGS. 2A through 2C are photographic images of construction materials coated with the UV paint of the present invention. Referring to FIGS. 2A through 2C, Example 1 (FIG. 2B) and Comparative Example 1 (FIG. 2A) exhibit a similar surface state, while Comparative Example 3 (FIG. 2C) has defects in appearance due to lightening of the color caused by the green tea.

[109] Evaluation of water and discoloration resistance for construction material using the

UV paint

[110] FIGS. 3 A through 3C are photographic images showing water and discoloration resistance of construction materials coated with the UV paint. The water and discoloration resistance of the flooring material (arboretum heated floor) used in the measurement of the TVOC dissipation rate was evaluated. After cutting the sample to a size of 100 mm(length) x 50 mm (width), the sample was immersed at a depth of 3 cm in water at 25 ⁰ C . By continuously observing for 1, 3, 5, and 7 days, discoloration of the new product was judged in comparison with a commercially available heated floor. A brightness difference at a visible light range was compared using Labscan XE equipment of Hunter Lab. FIG. 3D illustrates brightness of construction materials coated with the UV paint. Referring to FIG. 3D, Examples 1 and 2, and Comparative Example 1 have a similar brightness, while Comparative Example 3 containing 9 wt% of the green tea exhibits a brightness difference.

[I l l] Referring to FIGS. 3A through 3C, Example 1 (FIG. 3B) has similar water and discoloration resistance to Comparative Example 1 (FIG. 3A), while Comparative Example 3 (FIG. 3C) changes into a deep green color.

[112] The functional UV paint according to an embodiment of the present invention can reduce VOCs of a product using the same as well as VOCs and HCHO of the paint itself.

[113] While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the

following claims.

Industrial Applicability The functional UV paint according to the present invention can reduce VOCs of a product using the same as well as VOCs and HCHO of the paint itself.