Hard-coating composition for decorative sheet and decorative sheet prepared therefrom

Abstract

A hard-coating composition for a decorative sheet and a decorative sheet prepared therefrom according to the present invention comprise an acrylate monomer component, an acrylate oligomer component, and an oxysilane-containing compound. Accordingly, both a glossy surface and a matte surface can be achieved through a single coating solution, and glossy points do not form, even without the use of matting agents and / or particles, and thus a product has excellent appearance uniformity and high contamination resistance.

Description

Hard coating composition for decorative sheets and decorative sheets manufactured therefrom

[0001] The present invention relates to a hard coating composition for a decorative sheet for decoration and protection of a skin attachment, and to a decorative sheet manufactured therefrom, and more particularly, to a hard coating composition for a decorative sheet capable of implementing both a glossy surface and a matte surface using a single coating solution, and having excellent uniformity in the appearance of a product by not generating a glossy point even without using a matting agent and / or particles, and having excellent contamination resistance, and to a decorative sheet manufactured therefrom.

[0002] Traditionally, decorative sheets have been widely used to decorate and protect the surfaces of products such as home appliances, electronic products, construction, furniture, and automobiles. These decorative sheets are classified into glossy and matte types based on their surface shape.

[0003] While a glossy surface can be achieved in a deco sheet by excluding particles or phase-separated components that can cause light scattering after the coating composition is cured, a matte surface requires particles or additives that can increase surface roughness to be included in the material composition because light scattering must occur on the surface after the coating composition is cured. Due to these differences between glossy and matte surfaces, it has been a difficult task in the art to provide a deco sheet that can simultaneously have both a glossy and matte surface using a single coating composition. In this way, a coating composition that can have both a glossy and matte surface using a single coating composition is highly desirable from a productivity perspective because it allows the production of deco sheets by freely selecting the glossy or matte surface after coating. However, its implementation is currently very difficult.

[0004] To solve this problem, a recently widely used technology is to form a microfolding pattern on the surface of a coating composition using 172 nm excimer UV. This technology utilizes the phenomenon that 172 nm excimer UV only cures the surface of the coating composition by about 1 ㎛, and the lower uncured coating composition is absorbed into the upper cured coating surface, creating wrinkles on the surface. Therefore, when using this technology, there is no need to use additives that induce light scattering, such as particles.

[0005] However, when forming a microfolding pattern using the above technology, glossy points inevitably occur. Here, glossy points refer to a peculiar pattern that intermittently appears in a shape extending from a center point when irradiating the surface of the coating composition with 172 nm excimer UV. This causes a difference in glossiness compared to the surrounding microfolding patterns, which acts as a defect that reduces the uniformity of the product's appearance when evaluating its appearance.

[0006] Therefore, in the coating curing technology using 172 nm excimer UV, a method is being used to form a flawless matte surface by adding a matting agent and particles to the coating composition to minimize the visibility of the glossy point. However, if a pattern is not formed on the coating surface, it is difficult to perfectly implement a glossy surface due to the light scattering characteristics of the matting agent and particles. In addition, some highly reactive materials contained in the oligomer material cause easy contamination by pollutants frequently encountered in the living environment, such as red wine, mustard, and coffee. Therefore, it is not easy to implement a coating composition that implements both a glossy surface and a matte surface with a single composition and at the same time has excellent contamination resistance.

[0007] The present invention has been devised to solve the above problems and to meet the conventional requirements, and the problem to be solved by the present invention is to provide a hard coating composition for a decorative sheet that can realize both a glossy surface and a matte surface using a single coating solution and has excellent product appearance uniformity and contamination resistance, and a decorative sheet manufactured therefrom.

[0008] The above and other objects and advantages of the present invention will become more apparent from the following description of preferred embodiments.

[0009] The above object is achieved by a hard coating composition for a decorative sheet, which comprises an acrylate monomer, an acrylate oligomer and an oxysilane-containing compound, and has a gloss of 60 degrees of 5% or less and a gloss of 85 degrees of 18% or less when treated with excimer having a dominant wavelength of 172 nm, and a gloss of 60 degrees of 90% or more when treated with multi-wavelength UV having a dominant wavelength of 280 nm to 380 nm.

[0010] Preferably, the acrylate monomer may include a monofunctional acrylate monomer and a difunctional acrylate monomer.

[0011] Preferably, the hard coating composition for the decorative sheet may contain 5 to 15 parts by weight of a monofunctional acrylate monomer and 10 to 25 parts by weight of a difunctional acrylate monomer.

[0012] Preferably, the monofunctional acrylate monomer may include at least one selected from 2-hydroxyethyl acrylate (2-HEA), 4-hydroxybutyl acrylate (4-HBA), 2-hydroxypropyl acrylate (2-HPA), 2-hydroxyethyl methacrylate (2-HEMA), hydroxypropyl methacrylate (HPMA), 2-ethylhexylacrylate (2EHA), isotecylacrylate (IDA), and phenol(io)acrylate (PHEA).

[0013] Preferably, the bifunctional acrylate monomer may include at least one selected from 1,6-hexanediol diacrylate (HDDA), hydroxypivalic neopentylglycol diacrylate (HPNDA), dipropylene glycol diacrylate (DPGDA), and tripropylene glycol diacrylate (TPGDA).

[0014] Preferably, the acrylate oligomer may include a 6-functional urethane acrylate oligomer and a 3-functional polyester acrylate oligomer.

[0015] Preferably, the hard coating composition for the decorative sheet may include 10 to 25 parts by weight of a 6-functional urethane acrylate oligomer and 40 to 60 parts by weight of a 3-functional polyester acrylate oligomer.

[0016] Preferably, the weight ratio of the 6-functional urethane acrylate oligomer and the 3-functional polyester acrylate oligomer may be 1:1.6 to 4.

[0017] Preferably, the oxysilane-containing compound may have a structure represented by the following chemical formula 1 or chemical formula 2.

[0018] (Chemical formula 1)

[0019]

[0020] Here, R is at least one of hydrogen or alkyl group, Aryl group, alkenyl group, cycloalkyl group, and acryl group, RA and RB are at least one of cross-linking groups including alkenes, alkynes, acrylates, carboxylic acids, alcohols, isocyanates, aldehydes, amines, urethane acrylates, and polyester acrylates, m and n are integers greater than or equal to 1, X is an integer greater than or equal to 1,

[0021] (Chemical formula 2)

[0022]

[0023] Here, R 1 and R 2 is at least one of cross-linking groups including alkenes, alkynes, acrylates, carboxylic acids, alcohols, isocyanates, aldehydes, amines, urethane acrylates, and polyester acrylates, and n is an integer greater than or equal to 1.

[0024] Preferably, the hard coating composition for the decorative sheet may contain 2 to 4 parts by weight of an oxysilane-containing compound.

[0025] Preferably, the hard coating composition for the decorative sheet may not contain particles and may also not contain a matting agent.

[0026] In addition, the above object is achieved by a decorative sheet comprising a substrate and a hard coating layer coated with the hard coating composition for the decorative sheet described above on at least one side of the substrate.

[0027] Preferably, the substrate may be at least one selected from the group consisting of polymers, wood, paper, metal and ceramic.

[0028] Preferably, the hard coating layer may have a ΔE before / after contamination of 0.2 or less for red wine, mustard, and coffee.

[0029] According to a hard coating composition for a decorative sheet according to one embodiment of the present invention and a decorative sheet manufactured therefrom, by implementing both a glossy surface and a matte surface depending on the curing method during the curing process of the hard coating composition for a decorative sheet after coating on the main surface of a skin attachment, there is an effect such that both a glossy surface and a matte surface can be formed with a single composition.

[0030] Furthermore, the present invention has excellent uniformity in the appearance of the product as it does not generate a glossy point even without using a matting agent and / or particles, and has excellent contamination resistance against household contaminants that are easily generated in daily life.

[0031] However, the effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description below.

[0032] Figure 1 is a cross-sectional schematic diagram of a decorative sheet according to one embodiment of the present invention.

[0033] FIG. 2a is a drawing for explaining a method for implementing a glossy surface of a decorative sheet according to one embodiment of the present invention.

[0034] FIG. 2b is a drawing for explaining a method for implementing a matte surface of a decorative sheet according to one embodiment of the present invention.

[0035] FIG. 3a is a photograph showing a glossy surface of a decorative sheet according to one embodiment of the present invention.

[0036] FIG. 3b is a photograph showing a matte surface of a decorative sheet according to one embodiment of the present invention.

[0037] Figure 4a is a photograph of the surface of a conventional decorative sheet taken under a microscope.

[0038] Figure 4b is a photograph of Figure 4a with the glossy point removed.

[0039] FIG. 4c is a photograph showing a pattern shape on a matte surface of a decorative sheet according to one embodiment of the present invention.

[0040] Figure 5a is a photograph showing the surface appearance of a conventional decorative sheet where glossy points have occurred.

[0041] Fig. 5b is a photograph showing the surface appearance of the decorative sheet from which the glossy point has been removed in Fig. 5a.

[0042] Figure 6a is a photograph showing the state after contamination with a surface contaminant in the decorative sheet of Example 1 according to the present invention.

[0043] Figure 6b is a photograph showing the state after contamination with a surface contaminant in the decorative sheet of Comparative Example 1 according to the present invention.

[0044] Hereinafter, with reference to the attached drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. The present invention may be implemented in various different forms and is not limited to the embodiments described herein.

[0045] In order to clearly explain the present invention in the drawings, parts that are not related to the description are omitted, and the same reference numerals are added to the same or similar components throughout the specification. In addition, the thickness is shown in the drawings to clearly express various layers and regions. In addition, when it is mentioned in this specification that an element is disposed "on" or "over" another element, the element may be disposed directly on the other element, or there may be elements interposed between the elements. On the other hand, when it is mentioned that an element is disposed "directly on" or "directly above" another element, there may not be interposed elements.

[0046] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. In the event of a conflict, the present specification, including its definitions, will govern. Furthermore, although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, suitable methods and materials are described herein.

[0047] In this specification, the terms "~-based resin", "~-based polymer", or / and "~-based copolymer" are broad concepts encompassing all of "~ resin", "~ polymer", "~ copolymer", or / and "derivatives of ~ resin, polymer, or copolymer." In addition, in this specification, the term "polymer or copolymer crosslinked with these resins" means "polymer or copolymer crosslinked with the aforementioned resin."

[0048] In this specification, “compound” is a broad concept that includes “monatomic molecules,” “oligomers,” and “polymer compounds including homopolymers and copolymers.”

[0049] The term "including" in this specification means that other components may be included rather than excluding other components unless specifically stated to the contrary.

[0050] The term "combination of these" in this specification means a mixture or combination of one or more of the described components.

[0051] As used herein, the term "and / or" is meant to include any and all combinations of one or more of the items described herein. As used herein, the term "or" means "and / or." The expressions "at least one" or "one or more" preceding elements herein may supplement the entire list of elements and do not imply that they supplement individual elements described above.

[0052] Unless otherwise stated herein, all percentages, parts, ratios, etc. are by weight. Additionally, whenever an amount, concentration, or other value or parameter is given as a range, a preferred range, or a list of upper preferred values ​​and lower preferred values, this should be understood to specifically disclose all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether ranges are separately disclosed.

[0053] When a range of numerical values ​​is mentioned in this specification, unless otherwise stated, the range is intended to include the endpoints and all integers and fractions within the range. The scope of the present invention is not intended to be limited to the specific values ​​mentioned when defining the range. Furthermore, each element in this specification is a concept that includes both singular and plural.

[0054] Fig. 1 is a cross-sectional schematic diagram of a decorative sheet according to one embodiment of the present invention. Referring to Fig. 1, a hard coating composition for a decorative sheet according to one embodiment of the present invention and a decorative sheet manufactured therefrom will be described in detail.

[0055] Referring to FIG. 1, a decorative sheet (100) according to one embodiment of the present invention may include a substrate (10) and a hard coating layer (20) formed by coating a hard coating composition for a decorative sheet on at least one surface of the substrate (10).

[0056] In one embodiment, the substrate (10) may be composed of at least one material selected from the group consisting of polymers, wood, paper, metal, and ceramics as a material for supporting the decorative sheet.

[0057] In addition, the hard coating layer (20) can be located on at least one side of the substrate (10), that is, on one or both sides of the substrate, and is formed by coating a hard coating composition for a decorative sheet on the surface of the substrate (10).

[0058] In one embodiment, the hard coating composition for a decorative sheet forming a hard coating layer (20) preferably includes an acrylate monomer, an acrylate oligomer, and an oxysilane-containing compound. The hard coating composition for a decorative sheet according to one embodiment of the present invention can implement both a glossy surface and a matte surface with a single composition. A decorative sheet having a glossy surface should have a Gloss of 90% or more at 60 degrees and a smooth surface, so that the surface roughness should be very low, such as Ra 0.0098 to 0.0178 and Rz 0.101 to 0.206, whereas a decorative sheet having a matte surface should have a Gloss of 5% or less at 60 degrees and Gloss of 18% or less at 85 degrees, and a surface roughness of Ra 0.615 to 0.965 and Rz 3.978 to 5.723, which are implemented much higher than a decorative sheet having a glossy surface. The present invention has the technical feature that both the glossy surface and the matte surface described above can be realized with a single composition according to the method and conditions for curing the hard coating composition for decorative sheets described in FIGS. 2A and 2B described below. In addition, the hard coating composition for decorative sheets according to the present invention has the technical feature that, unlike conventional compositions, it does not use any particles such as additional inorganic particles and / or matting agents.

[0059] It is preferable that the acrylate monomer included in the hard coating composition for a decorative sheet according to one embodiment of the present invention includes a monofunctional acrylate monomer and a difunctional acrylate monomer.

[0060] For example, the monofunctional acrylate monomer (or monofunctional acrylic monomer) used in the hard coating composition for a decorative sheet according to one embodiment of the present invention controls the viscosity of the hard coating composition and improves the adhesion between the substrate and the hard coating layer, and includes 2-hydroxyethyl acrylate (2-HEA), 4-hydroxybutyl acrylate (4-HBA), 2-hydroxypropyl acrylate (2-HPA), 2-hydroxyethyl methacrylate (2-HEMA), hydroxypropyl methacrylate (HPMA), 2-ethylhexyl acrylate (2EHA), isotecyl acrylate (IDA), and It is preferable to include at least one of the acrylic monomers having a single functional group known in the art, such as phenol (EO) acrylate (PHEA), and it is more preferable to use 2-ethylhexyl acrylate (2EHA) without a hydroxyl group alone to improve stain resistance.

[0061] In addition, the bifunctional acrylate monomer (acrylic monomer having two functional groups) used in the hard coating composition for a decorative sheet according to one embodiment of the present invention is used to control the viscosity of the coating composition and increase the reactivity, and preferably includes at least one of the acrylic monomers having two functional groups known in the art, such as 1,6-hexanediol diacrylate (HDDA), hydroxypivalic neopentylglycol diacrylate (HPNDA), dipropylene glycol diacrylate (DPGDA), and tripropylene glycol diacrylate (TPGDA), and it is more preferable to use 1,6-hexanediol diacrylate (HDDA) without an ether alone to improve stain resistance.

[0062] In one embodiment, the content of the monofunctional acrylate monomer in the hard coating composition for the decorative sheet is preferably 5 to 15 parts by weight, more preferably 7 to 10 parts by weight. If the content of the monofunctional acrylate monomer is less than 5 parts by weight, there is a concern that it may be difficult to control the viscosity of the hard coating composition or the adhesion between the substrate and the hard coating layer may be insufficient, and if it exceeds 15 parts by weight, the content of the bifunctional or higher acrylate monomer may decrease, resulting in a decrease in the hardness of the coating surface.

[0063] In addition, the content of the difunctional acrylate monomer in the hard coating composition for decorative sheets is preferably 10 to 25 parts by weight, and more preferably 15 to 20 parts by weight. If the content of the difunctional acrylate monomer is less than 10 parts by weight, there is a concern that the viscosity control of the coating composition may become difficult or the hardness of the coating surface may decrease, and if it exceeds 25 parts by weight, the viscosity control of the coating composition may likewise become difficult and the reactivity may become excessively high.

[0064] The acrylate monomer described herein means not only acrylate but also methacrylate or any derivative in which a substituent is introduced into acrylate or methacrylate.

[0065] It is preferable that the acrylate oligomer included in the hard coating composition for a decorative sheet according to one embodiment of the present invention includes a 6-functional urethane acrylate oligomer and a 3-functional polyester acrylate oligomer.

[0066] A hard coating composition for a decorative sheet according to one embodiment of the present invention can form a wave pattern upon excimer irradiation by mixing a 6-functional urethane acrylate oligomer and a 3-functional polyester acrylate oligomer, and can implement a matte surface with completely removed glossy points by adjusting the surface energy of the hard coating composition to be as close as possible to that of a substrate by adding an oxysilane-containing compound as a surface energy control agent without using any particles.

[0067] More specifically, the hard coating layer formed through the hard coating composition for a decorative sheet according to one embodiment of the present invention can satisfy a gloss of a matte surface of 5% or less at Gloss 60 degrees and 18% or less at Gloss 85 degrees when treated with excimer having a dominant wavelength of 172 nm, and further, the hard coating layer formed through the hard coating composition for a decorative sheet according to one embodiment of the present invention can satisfy a gloss of 90% or more at Gloss 60 degrees when treated with multi-wavelength UV having a dominant wavelength of 280 nm to 380 nm, when treated with multi-wavelength UV.

[0068] In addition, the hard coating layer formed through the hard coating composition for a decorative sheet according to one embodiment of the present invention can maintain ΔE before / after contamination with red wine, mustard, and coffee at 0.2 or less, and thus has excellent contamination resistance against living contaminants that are easily generated in daily life.

[0069] The hexafunctional urethane acrylate oligomer used in the hard coating composition for a decorative sheet according to one embodiment of the present invention is a hexafunctional urethane acrylate oligomer having six acrylates, and preferably has a weight average molecular weight of 800 to 7,000. If the weight average molecular weight of the hexafunctional urethane acrylate oligomer is less than 800, there is a problem that the hard coating layer is damaged, and conversely, if the weight average molecular weight exceeds 7,000, there is a problem that the hardness of the hard coating layer is weakened. Since such a hexafunctional urethane acrylate oligomer has excellent reactivity, it can increase the hardness of the hard coating layer, and further, since the molecular weight is relatively large, it ensures excellent mechanical properties such as durability and pencil hardness after the hard coating layer is formed.

[0070] For example, examples of hexafunctional urethane acrylate oligomers include Miramer U360 (Miwon), Miramer PU610 (Miwon), Polygomer PN3601 (Polynetron), and Polygomer PN3657-6 (Polynetron).

[0071] In addition, the trifunctional polyester acrylate oligomer used in the hard coating composition for a decorative sheet according to one embodiment of the present invention is preferably a trifunctional polyester acrylate oligomer having three acrylates and having a weight average molecular weight of 1,300 to 7,500. When the weight average molecular weight of the trifunctional polyester acrylate oligomer is less than 1,300, there is a problem that the surface becomes rough due to the excessive generation of micro-folding patterns, and when it exceeds 7,500, there is a problem that the glossiness increases.

[0072] For example, examples of trifunctional polyester acrylate oligomers include Miramer PS420 (Miwon), Miramer PS4040 (Miwon), Miramer PS4500 (Miwon), Miramer PS4600 (Miwon), and Polygomer PN5350 (Polynetron).

[0073] In one embodiment, the content of the hexafunctional urethane acrylate oligomer in the hard coating composition for the decorative sheet is preferably 10 to 25 parts by weight. In this case, if the content of the hexafunctional urethane acrylate oligomer is less than 10 parts by weight, the hardness of the coating layer may be reduced, and if it is more than 25 parts by weight, the hard coating layer may become brittle and have reduced flexibility.

[0074] In addition, it is preferable that the content of the trifunctional polyester acrylate oligomer in the hard coating composition for the decorative sheet be 40 to 60 parts by weight. In this case, if the content of the trifunctional polyester acrylate oligomer is less than 40 parts by weight, there is a problem that the micro-folding pattern is formed too large, resulting in high gloss, and if it exceeds 60 parts by weight, there is a problem that the contamination resistance is reduced.

[0075] In one embodiment, the weight ratio of the 6-functional urethane acrylate oligomer and the 3-functional polyester acrylate oligomer, which are components of the hard coating composition for the decorative sheet, is preferably 1:1.6 to 4, thereby satisfying a gloss of 5% or less at 60 degrees and a gloss of 18% or less at 85 degrees, and maintaining ΔE before / after contamination of 0.2 or less for contaminants such as red wine, mustard, and coffee. Here, when the weight ratio of the 6-functional urethane acrylate oligomer and the trifunctional polyester acrylate oligomer is less than 1:1.6, i.e., when the content of the trifunctional polyester acrylate oligomer is insufficient, there is a problem that the micro-folding pattern is formed too large and the glossiness increases, and when the weight ratio of the 6-functional urethane acrylate oligomer and the trifunctional polyester acrylate oligomer is more than 1:4, i.e., when the content of the trifunctional polyester acrylate oligomer is excessive, there is a problem that the contamination resistance is seriously reduced.

[0076] In this way, in the present invention, an effective oligomer combination for implementing a matte surface and improving contamination resistance can be achieved through mixing a 6-functional urethane acrylate oligomer and a 3-functional polyester acrylate oligomer.

[0077] The oxysilane-containing compound used in the hard coating composition for a decorative sheet according to one embodiment of the present invention is preferably a compound having a structure represented by the following chemical formula 1 or chemical formula 2, which suppresses the occurrence of glossy points on a matte surface.

[0078] (Chemical formula 1)

[0079]

[0080] Here, R is at least one of hydrogen or an alkyl group, Aryl group, alkenyl group, cycloalkyl group, and acryl group, RA and RB are at least one of cross-linking groups including alkenes, alkynes, acrylates, carboxylic acids, alcohols, isocyanates, aldehydes, amines, urethane acrylates, and polyester acrylates, m and n are integers greater than or equal to 1, and X is an integer greater than or equal to 1.

[0081] (Chemical formula 2)

[0082]

[0083] Here, R 1 and R 2 is at least one of cross-linking groups including alkenes, alkynes, acrylates, carboxylic acids, alcohols, isocyanates, aldehydes, amines, urethane acrylates, and polyester acrylates, and n is an integer greater than or equal to 1.

[0084] For example, the oxysilane-containing compound according to Chemical Formula 2 can be a multifunctional silicone-modified urethane acrylate oligomer, and commercially available products include SIU2400 (Miwon) and PN8941 (Polynetron).

[0085] In one embodiment, it is preferred that the hard coating composition for the decorative sheet include 2 to 4 parts by weight of an oxysilane-containing compound. If the content of the oxysilane-containing compound is outside the above range, a glossy point will occur when forming a matte pattern, so it is preferred that it be within the above range.

[0086] In addition, the hard coating composition for a decorative sheet according to one embodiment of the present invention may further include a leveling additive and a photoinitiator.

[0087] FIG. 2a is a drawing for explaining a method for implementing a glossy surface of a decorative sheet according to one embodiment of the present invention, and FIG. 2b is a drawing for explaining a method for implementing a matte surface of a decorative sheet according to one embodiment of the present invention. And, as a decorative sheet manufactured through the method illustrated in FIGS. 2a and 2b, FIG. 3a is a photograph showing a glossy surface of a decorative sheet according to one embodiment of the present invention, and FIG. 3b is a photograph showing a matte surface of a decorative sheet according to one embodiment of the present invention. In FIGS. 2a and 2b, identification number "10" represents a substrate, "21" represents a hard coating layer coated with a hard coating composition, and "200" represents a coater.

[0088] Referring to FIG. 2a, a hard coating composition according to an embodiment of the present invention is coated on a decorative substrate, and then exposed to Hg UV at 172 mJ / cm2 in a N2 state (nitrogen atmosphere) to form a hard coating layer (21) having a glossy surface with a gloss of 60 degrees of 90% or more. And, referring to FIG. 2b, a hard coating composition according to an embodiment of the present invention is coated on a decorative substrate, and then exposed to 172 nm excimer UV at 150 mJ / cm2 in a N2 state (nitrogen atmosphere) and then exposed to Hg UV at 172 mJ / cm2 in air or N2 state to form a hard coating layer (21) having a matte surface with a gloss of 60 degrees of 5% or less and a gloss of 85 degrees of 18% or less.

[0089] Fig. 4a is a photograph showing a glossy point by looking at the surface of a conventional decorative sheet under a microscope, and Fig. 4b is a photograph showing the glossy point removed from Fig. 4a. In addition, Fig. 4c is a photograph showing a pattern shape on a matte surface of a decorative sheet according to one embodiment of the present invention.

[0090] In addition, Fig. 5a is a photograph showing the surface appearance of a conventional decorative sheet with glossy points, and Fig. 5b is a photograph showing the surface appearance of a decorative sheet with glossy points removed in Fig. 5a.

[0091] As described above, even if a pattern satisfying a gloss of 5% or less at Gloss 60 degrees and 18% or less at Gloss 85 degrees is formed by mixing a 6-functional urethane acrylate oligomer and a 3-functional polyester acrylate oligomer, the product cannot be used if a glossy point is generated on the surface of the pattern due to particles such as inorganic particles or matting agents included in the composition.

[0092] Accordingly, it is recognized that when the difference in surface energy between a substrate and a hard coating composition is minimized as a method for removing glossy points, defects occurring on the surface such as glossy points can be removed, and in order to realize this, the present invention provides a hard coating composition for a decorative sheet that can suppress the occurrence of glossy points and create a matte surface that can be manufactured by adding 2 to 4 parts by weight of an oxysilane-containing compound to a hard coating composition for a decorative sheet without using any particles such as inorganic particles and / or a matting agent in the hard coating composition, coating the hard coating composition on a substrate, and then irradiating the coating surface with a 172 nm excimer to form a matte pattern. In this way, the hard coating composition for a decorative sheet according to one embodiment of the present invention is produced by applying a hard coating composition containing 2 to 4 parts by weight of an oxysilane-containing compound to a substrate without using any particles such as a matting agent and / or particles, and the gloss of the matte surface is 5% or less at 60 degrees, 18% or less at 85 degrees, and the gloss of the glossy surface satisfies 90% or more at 60 degrees.

[0093] In addition, unlike conventional decorative sheets, the present invention does not generate glossy points even without using a matting agent and / or particles, so the product has excellent uniformity in appearance.

[0094] Hereinafter, the composition and resulting effects of the present invention will be described in more detail through examples and comparative examples. However, these examples are intended to more specifically illustrate the present invention, and the scope of the present invention is not limited to these examples.

[0095] [Example]

[0096] [Example 1]

[0097] 1. Preparation of hard coating composition

[0098] After mixing 17.3 parts by weight of 6-functional urethane acrylate oligomer (PN3601, Polynetron, MW 1,500) and 51.9 parts by weight of 3-functional polyester acrylate oligomer (PN5350, Polynetron, MW 3,000), add 8.09 parts by weight of 1-functional acrylate monomer (2-ethylhexyl acrylate, 2EHA, Sigma-Aldrich) and 16.2 parts by weight of 2-functional acrylate monomer (1,6-hexanediol diacrylate, HDDA, Miwon) to lower the viscosity. Next, 3.64 parts by weight of an oxysilane-containing compound having a structure of chemical formula 2 (PN8941, Polynetron, MW 3,000), 0.13 parts by weight of a leveling agent (BYK333, BYK), and 2.69 parts by weight of a photoinitiator were added and stirred to prepare a hard coating composition.

[0099] 2. Manufacturing of decorative sheets

[0100] Using the above hard coating composition, decorative sheets were manufactured in the form of matte surface samples and glossy surface samples, respectively, as follows.

[0101] (1) Matte surface sample

[0102] After coating the hard coating composition manufactured above on a decorative substrate, it was exposed to 172 nm excimer under N2 conditions at 150 mJ / cm2, and then exposed to Hg UV with a wavelength of 330 nm in air at 172 mJ / cm2 to form a matte surface, thereby manufacturing a matte decorative sheet.

[0103] (2) Glossy surface sample

[0104] After coating the hard coating composition manufactured above on a decorative substrate, a glossy decorative sheet was manufactured by exposing it to Hg UV with a wavelength of 330 nm at 172 mJ / cm2 under N2 conditions to form a glossy surface.

[0105] [Example 2]

[0106] A hard coating composition and a decorative sheet were prepared in the same manner as in Example 1, except that 19.8 parts by weight of a 6-functional urethane acrylate oligomer (PN3601, Polynetron Co., Ltd., MW 1,500) and 49.4 parts by weight of a 3-functional polyester acrylate oligomer (PN5350, Polynetron Co., Ltd., MW 3,000) were mixed.

[0107] [Example 3]

[0108] After mixing 15.4 parts by weight of 6-functional urethane acrylate oligomer (PN3601, Polynetron, MW 1,500) and 46.3 parts by weight of 3-functional polyester acrylate oligomer (PN5350, Polynetron, MW 3,000), add 10.8 parts by weight of 1-functional acrylate monomer (2-ethylhexyl acrylate, 2EHA, Sigma-Aldrich) and 21.7 parts by weight of 2-functional acrylate monomer (1,6-hexanediol diacrylate, HDDA, Miwon) to lower the viscosity. Next, 3.25 parts by weight of an oxysilane-containing compound having a structure of chemical formula 2 (PN8941, Polynetron, MW 3,000), 0.12 parts by weight of a leveling agent (BYK333, BYK), and 2.4 parts by weight of a photoinitiator were added and stirred to prepare a hard coating composition, and a decorative sheet was prepared in the same manner as in Example 1.

[0109] [Example 4]

[0110] A hard coating composition and a decorative sheet were prepared in the same manner as in Example 3, except that 13.7 parts by weight of a 6-functional urethane acrylate oligomer (PN3601, Polynetron Co., Ltd., MW 1,500) and 48 parts by weight of a 3-functional polyester acrylate oligomer (PN5350, Polynetron Co., Ltd., MW 3,000) were mixed.

[0111] [Example 5]

[0112] A hard coating composition and a decorative sheet were manufactured in the same manner as in Example 1, except that the content of the components of the hard coating composition was configured as shown in Table 1 so that the weight ratio of the 6-functional urethane acrylate oligomer (PN3601, Polynetron Co., Ltd., MW 1,500) and the 3-functional polyester acrylate oligomer (PN5350, Polynetron Co., Ltd., MW 3,000) was 1:1.6.

[0113] [Comparative example]

[0114] [Comparative Example 1]

[0115] A hard coating composition and a decorative sheet were prepared in the same manner as in Example 3, except that a trifunctional urethane acrylate oligomer (PN3330, Polynetron, MW 1,500) was used instead of a trifunctional polyester acrylate oligomer (PN5350, Polynetron, MW 3,000).

[0116] [Comparative Example 2]

[0117] A hard coating composition and a decorative sheet were manufactured in the same manner as in Example 1, except that a trifunctional urethane acrylate oligomer (PN3330, Polynetron, MW 1,500) was used instead of a trifunctional polyester acrylate oligomer (PN5350, Polynetron, MW 3,000), and the contents of the components of the hard coating composition were as shown in Table 2.

[0118] [Comparative Example 3]

[0119] A hard coating composition and a decorative sheet were manufactured in the same manner as in Example 1, except that a trifunctional urethane acrylate oligomer (PN3330, Polynetron, MW 1,500) was used instead of a trifunctional polyester acrylate oligomer (PN5350, Polynetron, MW 3,000), an oxysilane-containing compound was not used, 1.48 parts by weight of a matting agent (PE particle CEARFLOUR 990, BYK) was added, and the contents of the components of the hard coating composition were as shown in Table 2.

[0120] [Comparative Example 4]

[0121] A hard coating composition and a decorative sheet were manufactured in the same manner as in Example 1, except that a trifunctional urethane acrylate oligomer (PN3330, Polynetron, MW 1,500) was used instead of a trifunctional polyester acrylate oligomer (PN5350, Polynetron, MW 3,000), an oxysilane-containing compound was not used, 1.48 parts by weight of Si-based particles (fumed silica Aerosil 200, Evonik) were added, and the contents of the components of the hard coating composition were as shown in Table 2.

[0122] [Comparative Example 5]

[0123] A hard coating composition and a decorative sheet were prepared in the same manner as in Example 1, except that the content of the components of the hard coating composition was configured as shown in Table 2 so that the weight ratio of the 6-functional urethane acrylate oligomer (PN3601, Polynetron Co., Ltd., MW 1,500) and the 3-functional polyester acrylate oligomer (PN5350, Polynetron Co., Ltd., MW 3,000) was 1:1.

[0124] [Comparative Example 6]

[0125] A hard coating composition and a decorative sheet were manufactured in the same manner as in Example 1, except that the content of the components of the hard coating composition was configured as shown in Table 2 so that the weight ratio of the 6-functional urethane acrylate oligomer (PN3601, Polynetron Co., Ltd., MW 1,500) and the 3-functional polyester acrylate oligomer (PN5350, Polynetron Co., Ltd., MW 3,000) was 1:4.5.

[0126] The physical properties were measured using the decorative sheets according to Examples 1 to 5 and Comparative Examples 1 to 6 through the following experimental examples, and the results are shown in Tables 1 and 2 below.

[0127] [Experimental Example]

[0128] 1. Appearance evaluation

[0129] 1st evaluation: Visual evaluation was performed to check for defects on the coating surface.

[0130] Secondary evaluation: Using an optical microscope with a magnification of X10 to X20, it was confirmed whether the glossy point appearance of the decorative sheet had deteriorated in relation to the defects identified in the first evaluation.

[0131] 2. Gloss evaluation

[0132] The 20° gloss (gloss 20° condition), 60° gloss (gloss 60° condition), and 85° gloss (gloss 85° condition) of the decorative sheet were measured using a gloss meter according to ASTM D2457.

[0133] 3. ΔE measurement

[0134] The ΔE values ​​of the coating surface before and after contamination were measured using a colorimeter (CM-3600A). At this time, the substrate of the coating sample was black PET, and the contaminants used were red wine, mustard, and coffee. Then, the contaminants were applied to the coating surface with a diameter of 3 cm and left at room temperature for 16 hours (covered with a glass cover to prevent drying). After 16 hours, the contaminants were covered with a cloth under running water, the moisture was removed, and the ΔE values ​​were measured.

[0135] 4. Tactile evaluation

[0136] The texture of the decorative sheet was evaluated by rubbing it 2-3 times directly against the surface to be measured with a human index finger and comparing it with the texture of the grit of sandpaper, and the following criteria were presented in the table.

[0137] Soft: 320~600 Girt

[0138] Mirror: If the feel is similar to a mirror

[0139] rough: 180~280 Girt

[0140] 5. Surface roughness measurement

[0141] The surface roughness (Ra, Rz) of the decorative sheet was measured based on ISO 4287.

[0142]

[0143]

[0144] As can be seen from Tables 1 and 2 above, the decorative sheets including the hard coating compositions for decorative sheets according to Examples 1 to 5 that satisfy all of the configurations of the present invention have a gloss of Gloss 60 degrees of 5% or less and Gloss 85 degrees of 18% or less on a matte surface without a glossy point even though only one hard coating composition for decorative sheets was used, and it can be confirmed that the gloss of the glossy surface is Gloss 60 degrees of 90% or more. Therefore, it can be seen that both a glossy surface and a matte surface can be implemented using one hard coating composition. In addition, it can be confirmed that the decorative sheet including the hard coating composition for the decorative sheet according to Examples 1 to 5 has excellent uniformity in the appearance of the product as no glossy point occurs even when no particles such as a matting agent and / or particles are used in the hard coating composition, and it can be confirmed that the decorative sheet has excellent contamination resistance as the ΔE value is 0.2 or less for household contaminants such as red wine, mustard, and coffee.

[0145] On the other hand, it can be confirmed that Comparative Example 1 has poor stain resistance with a ΔE value exceeding 0.2 for red wine and mustard stains. This can be confirmed through the contents described in Tables 1 and 2 described above as well as through FIGS. 6a and 6b. FIG. 6a is a photograph showing the state after being stained with a surface stain in the decorative sheet of Example 1, and FIG. 6b is a photograph showing the state after being stained with a surface stain in the decorative sheet of Comparative Example 1. Comparing FIGS. 6a and 6b, it can be seen that, compared to Example 1, where the ΔE value is less than 0.2 (ΔE<0.2), Comparative Example 1 has a ΔE value exceeding 0.2 (ΔE>0.2), showing a greater change in color difference (ΔE).

[0146] In addition, it can be confirmed that the decorative sheet of Comparative Example 2 has poor stain resistance with a ΔE value exceeding 0.2 for the sources of contamination, such as red wine, mustard, and coffee, and it can be confirmed that the gloss of the glossy surface is less than 90% at 60 degrees, so it does not achieve the gloss of the glossy surface.

[0147] In addition, the deco sheet of Comparative Example 3 had a gloss of 60 degrees exceeding 5% on a matte surface and a gloss of 60 degrees below 90% on a glossy surface, failing to achieve glossiness for both the glossy and matte surfaces. In addition, it was confirmed that the ΔE value exceeded 0.2 for the contaminants red wine, mustard, and coffee, indicating poor stain resistance. In addition, it was confirmed that the deco sheet of Comparative Example 4 had a ΔE value exceeding 0.2 for the contaminants red wine, mustard, and coffee, indicating poor stain resistance. Furthermore, it was confirmed that Comparative Examples 3 and 4, in which SI particles or a matting agent were used in the hard coating layer, generated glossy points on the matte surface.

[0148] In addition, it can be confirmed that Comparative Example 5 has a large number of glossy points and an increased glossiness, and Comparative Example 6 has a low contamination resistance.

[0149] Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present invention defined in the following claims also fall within the scope of the present invention.

Claims

1. Containing an acrylate monomer, an acrylate oligomer and an oxysilane-containing compound, When treated with an excimer with a main wavelength of 172 nm, the gloss is 5% or less at Gloss 60 degrees and 18% or less at Gloss 85 degrees. A hard coating composition for decorative sheets, having a gloss of 60 degrees or more and a gloss of 90% or more when treated with multi-wavelength UV having a main wavelength of 280 nm to 380 nm.

2. In paragraph 1, A hard coating composition for a decorative sheet, wherein the acrylate monomer comprises a monofunctional acrylate monomer and a difunctional acrylate monomer.

3. In paragraph 2, A hard coating composition for a decorative sheet, comprising 5 to 15 parts by weight of the monofunctional acrylate monomer and 10 to 25 parts by weight of the difunctional acrylate monomer.

4. In paragraph 2, A hard coating composition for a decorative sheet, wherein the above monofunctional acrylate monomer comprises at least one selected from among 2-hydroxyethyl acrylate (2-HEA), 4-hydroxybutyl acrylate (4-HBA), 2-hydroxypropyl acrylate (2-HPA), 2-hydroxyethyl methacrylate (2-HEMA), hydroxypropyl methacrylate (HPMA), 2-ethylhexylacrylate (2EHA), isotecylacrylate (IDA), and phenol(io)acrylate (PHEA).

5. In paragraph 2, A hard coating composition for a decorative sheet, wherein the above bifunctional acrylate monomer comprises at least one selected from 1,6-hexanediol diacrylate (HDDA), hydroxypivalic neopentyl glycol diacrylate (HPNDA), dipropylene glycol diacrylate (DPGDA), and tripropylene glycol diacrylate (TPGDA).

6. In paragraph 1, A hard coating composition for a decorative sheet, wherein the above acrylate oligomer comprises a 6-functional urethane acrylate oligomer and a 3-functional polyester acrylate oligomer.

7. In paragraph 6, A hard coating composition for a decorative sheet, comprising 10 to 25 parts by weight of the hexafunctional urethane acrylate oligomer and 40 to 60 parts by weight of the trifunctional polyester acrylate oligomer.

8. In paragraph 6, A hard coating composition for a decorative sheet, wherein the weight ratio of the 6-functional urethane acrylate oligomer and the 3-functional polyester acrylate oligomer is 1:1.6 to 4.

9. In paragraph 1, The above oxysilane-containing compound has a structure represented by the following chemical formula 1 or chemical formula 2, (Chemical formula 1) Here, R is at least one of hydrogen or alkyl group, Aryl group, alkenyl group, cycloalkyl group, and acryl group, RA and RB are at least one of cross-linking groups including alkenes, alkynes, acrylates, carboxylic acids, alcohols, isocyanates, aldehydes, amines, urethane acrylates, and polyester acrylates, m and n are integers of 1 or more, X is an integer of 1 or more, (Chemical formula 2) Here, R 1 and R 2 A hard coating composition for a decorative sheet, wherein n is at least one of cross-linking groups including alkenes, alkynes, acrylates, carboxylic acids, alcohols, isocyanates, aldehydes, amines, urethane acrylates, and polyester acrylates, and n is an integer of 1 or more.

10. In paragraph 1, A hard coating composition for a decorative sheet, comprising 2 to 4 parts by weight of the oxysilane-containing compound.

11. In paragraph 1, The hard coating composition for the above decorative sheet is a hard coating composition for the decorative sheet that does not contain particles.

12. In paragraph 1, The hard coating composition for the above decorative sheet is a hard coating composition for the decorative sheet that does not contain a matting agent.

13. A decorative sheet comprising a hard coating layer coated with a hard coating composition for a decorative sheet according to any one of claims 1 to 12 on at least one side of the substrate.

14. In paragraph 13, The above-mentioned decorative sheet is at least one selected from the group consisting of polymers, wood, paper, metal and ceramic.

15. In paragraph 13, The above hard coating layer is a decorative sheet having a ΔE of 0.2 or less before / after contamination with red wine, mustard, and coffee.

Images