KR20210078618A - Decoration film with improved weatherability - Google Patents

Abstract

The present invention relates to a sheet for improving weather resistance, comprising: a base film layer; a complementary coating layer positioned on the base film layer; and a transparent layer positioned on the supplementary coating layer, wherein a metal ion is included in any one or more of the transparent layer and the base film layer, and the supplementary coating layer includes a metal ion sequestering agent.

Description

Weatherability improvement sheet {DECORATION FILM WITH IMPROVED WEATHERABILITY}

The present invention relates to a weatherability improvement sheet, and more particularly, by applying a coating layer containing a metal ion sequestering agent to the surface of the PVC layer, the weather resistance that can suppress the effect of metal ions located on the PVC surface on PVC It relates to an improvement sheet.

Films for decoration purposes are coated or adhered to materials in various fields such as automobiles, building materials, advertising materials, flooring materials, and wallpaper for interior and exterior use. In the case of a coating material, the coating composition is directly applied to a target and then cured and applied, and there is a problem in that the realization of color is limited and vulnerable to change over time. On the other hand, in the case of a decorative film, a film based on a polyvinyl chloride (PVC) resin is mainly used, and the polyvinyl chloride resin has advantages of excellent transparency and colorability while being inexpensive. In addition, polyvinyl chloride resin, as a thermoplastic material, softens under external conditions to exhibit fluidity, and then hardens to become a solid when cooled. When external conditions are applied, polyvinyl chloride resin softens and exhibits fluidity again, so the molding processability is also very excellent. Therefore, the decorative film having such characteristics has the advantage of being able to implement various colors and designs.

In general, when using a pigment containing metal ions in such a decorative film, ^{since it contains free ion impurities such as metal ions in the pigment, for example Fe 2 +} , local yellowing (Brown) by UV irradiation for a long time. spots) may occur, and problems with weather resistance may occur.

In order to solve this problem, a PVC stabilizer was conventionally prescribed, but there was a limit to the improvement of aging due to metal ions appearing on the outermost surface of the base film layer as shown in FIG. 1 only by prescription of the PVC stabilizer.

Korean Patent Application Laid-Open No. 10-2002-0066593, "Laminate flooring containing metal-substituted zeolite powder"

The inventors of the present invention have studied to solve the above problems,

The problem is that, as shown in FIG. 1, metal ions affect the Cl part of the main chain of PVC included in the base film layer, so that it is very easily dechlorinated when an aging factor such as UV is applied. After confirming that this is due to progress, in order to solve this problem, a complementary coating layer containing a metal ion sequestering agent is introduced on the base film layer of the high weathering sheet constituting the exterior decoration film, and the metal ions are Cl of PVC. It was found that the weather resistance could be improved by preventing the weakening of the C-Cl bonding by applying an electrostatic force to it.

Accordingly, it is an object of the present invention to provide a weather resistance improvement sheet capable of suppressing the influence of metal ions located on the PVC surface on PVC.

In order to achieve the above object, the present invention, the base film layer; a complementary coating layer positioned on the base film layer; a printed layer positioned on the complementary coating layer; and a transparent layer positioned on the print layer, wherein at least one of the base film layer and the complementary coating layer contains metal ions, and the complementary coating layer provides a weatherability improvement sheet including a sequestering agent.

Weather resistance improvement sheet according to the present invention, by introducing a complementary coating layer containing a metal ion sequestering agent on top of the base film layer, by preventing metal ions from acting electrostatic force on Cl of PVC to weaken C-Cl bonding, weather resistance It has the advantage of being able to improve

1 is a schematic diagram showing that the C-Cl bond of PVC is weakened by metal ions included in a conventional decorative film for exterior.
Figure 2 is a schematic diagram showing that the metal ion sequestrant contained in the weatherability improvement sheet of the present invention prevents the metal ions from affecting the C-Cl bond of PVC, thereby preventing the weakening of the C-Cl bond of PVC.
3 is a schematic view showing the structure of a side cross-section of the weather-resistant sheet of the present invention.
4 is a schematic side cross-sectional view before and after the weather resistance evaluation of the weather resistance improvement sheet according to Comparative Examples (a) and (b) of the present invention.
5 is a photograph showing the results of performing the weather resistance evaluation after 8000 hours for each of the decorative films prepared in Examples 1 to 4 and Comparative Examples 1 to 2 of the present invention.

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

3, the weather resistance improvement sheet according to an embodiment of the present invention is a base film layer 400; a complementary coating layer 300 positioned on the base film layer; a printed layer 200 positioned on the complementary coating layer; and a transparent layer 100 positioned on the printed layer, wherein the base film layer 400 contains metal ions, and the complementary coating layer 300 contains a metal ion sequestering agent.

The present applicant, when using a pigment containing a metal ion, which is a problem of the decor films that have existed so far, metal ions in the pigment, for example, because it contains free ion impurities such as ^{Fe 2 +,} We have been continuously studying to improve weather resistance problems such as local brown spots caused by UV irradiation, and as a result of repeated research, this is the main chain of PVC in which metal ions are contained in the base film layer. It was confirmed that it is because dechlorination proceeds very easily when aging factors such as UV are applied by affecting the Cl part of the (main chain). By introducing a complementary coating layer containing a metal ion sequestering agent on top of the base film layer of the high weathering sheet, it is possible to improve weather resistance by preventing metal ions from acting electrostatically on Cl of PVC to weaken C-Cl bonding. revealed the facts This invention can be said to be the applicant's own invention, which has not been found so far.

Hereinafter, the weather resistance improvement sheet of the present invention will be described in more detail.

First, the weather resistance improvement sheet of the present invention includes a base film layer (400). The base film layer 400 is not only to improve weather resistance, but also to support the printed layer 200 , the transparent layer 100 and the complementary coating layer 300 , and may be formed in a sheet or film shape. The base film constituting the base film layer includes polyvinyl chloride resin (PVC). In addition, at least one selected from the group consisting of an acrylic resin, a thermoplastic polyolefin resin (TPO), an acrylonitrile butadiene styrene (ABS) copolymer, and an acrylonitrile styrene acrylate (ASA) may be further included. In addition, the base film layer of the present invention may further include a plasticizer.

In addition, any one or more of the base film layer and the complementary coating layer of the present invention may contain metal ions. The metal ions are included in the base film layer as the metal ions in the pigment move to the base film layer when a pigment containing metal ions among the pigments used in the printing layer of the present invention is used. The metal ion is selected from the group consisting of ^{Ca 2 +, Cd 2 +,} Co 2 +, Cu 2 +, Fe 2 +, Fe 3 +, Mg 2 +, Mn 2 +, Ni 2+ and Zn ^{+ 2,} etc. It may be any one or more, and preferably Fe ²⁺ , Fe ³⁺ , and the like.

The thickness of the base film layer 100 may be about 80 to about 400 μm, and by having a thickness within the above range, the complementary coating layer 300 without excessively increasing the total thickness of the decorative sheet according to the present invention. , the printed layer 200 and the transparent layer 100 can be sufficiently supported.

In addition, the base film layer 100 is an adhesive layer (not shown) on the side that does not face the printing layer 200 or the complementary coating layer 300 (that is, the side facing the target substrate to which the decorative film is to be attached). may include more. By attaching the sheet to the target article to be attached via the adhesive layer, the sheet may coat the target article as a surface finishing material of the target article. The adhesive layer may include at least one selected from the group consisting of a hydroxyl group-containing acrylic adhesive, a saturated polyester-based adhesive, a urethane-based adhesive, and combinations thereof. In addition, the adhesive layer may include an isocyanate-based curing agent exemplified by xylene diisocyanate (XDI), hexamethylene diisocyanate (HDI), methylene diphenyl diisocyanate (MDI), and toluene diisocyanate (TDI). The solvent may include a conventional solvent such as methyl ethyl ketone, toluene, ethyl acetate and methyl isobutyl ketone.

The adhesive layer may be formed by applying an adhesive such as polyester to a thickness of 10 to 15 μm by a comma coating method, and by forming an opaque layer, it is possible to produce a more beautiful and clear three-dimensional effect. In addition, when the adhesive layer is formed as an opaque layer, pigments of various colors may be added to the adhesive. In addition, a release film may be further attached to the opposite side of the adhesive layer that does not face the base film layer 100. In this case, the decorative film may be attached to the adherend after the release film is removed, for example, As a result, it can be applied as a finishing material for the interior or exterior of buildings, home appliances, electronic products, automobile interior/exterior materials, furniture, doors, and advertising materials. In addition, the base film layer 100 may further include a plasticizer for the purpose of imparting or increasing plasticity to the decorative film. Since it is a general technique to add a plasticizer to the base film layer of a conventional decor film, a detailed description thereof will be omitted.

Next, the weather resistance improvement sheet of the present invention includes a complementary coating layer (300).

The complementary coating layer 300 is to suppress the effect of metal ions located on the surface of the base film layer on PVC contained in the base film layer, by introducing a supplementary coating layer containing a metal ion sequestering agent on top of the base film layer. , It is possible to improve weather resistance by preventing metal ions from weakening the C-Cl bonding by applying electrostatic force to Cl of PVC. The complementary coating layer is cured as a thermosetting coating layer in addition to the metal ion sequestrant in order to have UV blocking performance and barrier performance at the same time, and any one or more selected from the group consisting of a polyurethane resin, a polyurea resin, and a fluorinated polyether resin. may include

The metal ion sequestrant included in the complementary coating layer 300 may be a chelate agent. The chelate agent refers to a multidentate ligand that coordinates with a metal ion to form a chelate compound. In the present invention, one or more selected from the group consisting of EDTA, citrate, glycine, glyphosate and AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) may be used as the chelate agent. and EDTA (Ethylenediamine-N, N, N', N'-tetraacetic acid) may be preferably used.

As the complementary coating layer 300 of the present invention includes the metal ion sequestering agent, as shown in FIG. 2, metal ions act electrostatic force on Cl of PVC present in the base film layer to weaken C-Cl bonding. By preventing it, the weather resistance can be improved.

Such a complementary coating layer 300 of the present invention may be formed to a thickness of 1 to 20 μm, preferably 2 to 20 μm, more preferably 2 to 10 μm. If the thickness of the complementary coating layer 300 satisfies the above range, there is a problem in that the product properties can be changed when the thickness exceeds the above range, and when used less than the thickness, the target effect properties are not properly implemented. There may be a problem.

The metal ion sequestrant included in the complementary coating layer 300 may be included in an amount of 0.1 to 5 wt%, preferably 0.5 to 3 wt%, more preferably 0.7 to 2 wt%, based on the total weight of the supplementary film layer. % by weight may be included. If the content of the sequestering agent is more than 5% by weight, the improvement effect due to the additional input may be insufficient, and may only cause an unnecessary cost increase, and if it is less than 0.1% by weight, the targeted effect may not appear.

In addition, the weather resistance improvement sheet of the present invention includes a printed layer (200). The printing layer 200 may include a binder resin including an acrylic resin or a vinyl resin and a urethane-based ink (pigment), and transfer printing, gravure printing, or screen printing on the upper surface of the complementary coating layer 300 . , may be formed by giving a pattern in various printing methods such as offset printing, rotary printing or flexographic printing. The thickness of the printing layer 200 may be about 1 to 20 μm, and by having a thickness within the above range, a sufficient pattern or color may be realized without excessively increasing the total thickness of the decorative sheet.

In addition, the weather resistance improvement sheet of the present invention includes a transparent layer (100). The transparent layer 100 is used to protect the base film layer 400 from external environmental factors such as UV, and all commercially available acrylic films for high weather resistance can be applied. In the case of the acrylic film, it includes an acrylate-based resin, acryl rubber particles having a core/shell structure, and a UV absorber, and HALS (Hindered Amine Light Stabilizer; Radical Scavenger) and antioxidants, etc. may further contain additives. The acrylate-based resin may be any acrylate-based resin used as a protective film component of a decor sheet in the art, and a representative polymethyl methacrylate (PMMA)-based resin may be exemplified, but is not limited thereto. reveal

The glass transition temperature (Tg) of the acrylate-based resin may be 50 to 120 ℃, preferably 60 to 120 ℃. When the glass transition temperature of the acrylate-based resin is less than the above range, it is usually processed by heating at 30 to 50° C. during construction of the decorative film, but at this time, there is a risk that the protective film may be melted or deformed by the temperature. In addition, when the glass transition temperature of the acrylate-based resin exceeds the above range, when used together with an impact modifier, interficail debonding occurs between the acrylate-based resin and the impact modifier, and the acrylate-based resin and the impact As voids are formed between the reinforcing materials, a problem of causing whitening of the tensile or bending portion may occur.

The acrylic rubber particles having the core/shell structure include, for example, a copolymer of a core portion including a butyl acrylate resin and a methyl methacrylate (MMA) monomer and a butyl acrylate (BA) monomer. It may include a shell portion that does (however, this is only an example for the convenience of description, note that all impact reinforcing materials used in the art can be applied).

In addition, the transparent layer 100 may further include a UV stabilizer in an amount of 0.1 to 5% by weight based on the total weight of the transparent layer. If the UV stabilizer is used in an amount of less than 0.1% by weight based on the total weight of the transparent layer, the weather resistance of the product may be insufficient, and if it exceeds 5% by weight, problems such as migration and initial color discoloration may occur. The UV stabilizer is not particularly limited in its type, for example, 2-hydroxybenzophenone, 2-hydroxyphenylbenzotriazole, hydroxyphenyltriazine, hindered amine, organic nickel compound, sali It may include any one or more selected from the group consisting of sylate, resorcinol monobenzoate, cinnamate derivative, oxanilide, para-hydroxybenzoate, and combinations thereof.

The transparent layer may have a thickness of 30 to 100 μm. If the thickness of the transparent layer is less than 30um, problems such as excessive elongation may occur due to lack of mechanical properties during the processing of the entire product, and if the thickness is more than 100um, problems such as lifting may occur during construction of sharp parts.

Hereinafter, the present invention will be described in more detail through specific examples. The following examples are intended to illustrate the present invention, but the present invention is not limited by the following examples.

[Example 1] Preparation of decorative film

First, a 200 μm thick base film layer containing polyvinyl chloride resin (LG Chemical, LS100) was prepared. The base film layer included black inorganic pigments containing Fe free ions and processed a sheet in Dark Gray series. Afterwards, in a coating solution in which an acrylic polyol resin (BASF, Joncryl RPD980, Joncryl 950, 2 types, 1:1) and a curing agent (BASF, Basonat HI100) are mixed so that the equivalence ratio is 1:1.05 based on the OH group of the acrylic polyol resin, a UV absorber (BASF Tinuvin 1577) 1.0% by weight and 1.0% by weight of EDTA were further mixed, respectively, and then a complementary coating layer having a thickness of 5 μm was formed on the base film layer by a microgravure printing method. Then, gravure printing was performed with an acrylic ink composition to laminate a 2 μm print layer, and finally, a 53 μm thick acrylic film (commercially available product) containing Tinuvin234 was formed on the printed layer to prepare a sheet.

[Example 2] Preparation of decorative film

A sheet was manufactured in the same manner as in Example 1, except that citrate was used instead of EDTA as a sequestering agent.

[Example 3] Preparation of decorative film

A sheet was prepared in the same manner as in Example 1, except that glycine was used instead of EDTA as a sequestering agent.

[Example 4] Preparation of decorative film

A sheet was manufactured in the same manner as in Example 1, except that glyphosate was used instead of EDTA as a sequestering agent.

[Comparative Example 1] Preparation of a conventional decorative film

An external decorative film was manufactured in the same manner as in Example 1, except that a base film layer, a printed layer, and a transparent layer were sequentially laminated without forming a complementary coating layer.

[Comparative Example 2] Preparation of a conventional decorative film-2

Without forming a complementary coating layer, only the base film layer, the printing layer and the transparent layer were sequentially laminated, and compared to Comparative Example 1, a transparent layer with a reinforced UV stabilizer prescription was applied. A deco film was produced.

[Test Example 1] Weather resistance evaluation of the decorative film

Each of the decor films prepared in Examples 1 to 4 and Comparative Examples 1 to 2 was evaluated for weather resistance using Q-Lab's QUV equipment. Specifically, UVA-340 lamp and Outdoor Sun Light Simulation Filter were used for weather resistance evaluation, and the evaluation cycle consisted of 3 steps in 1 cycle, UV irradiation alone in 1 Step, UV irradiation in 2 Step + Spray It was exposed to UV + condensation environment in 3 Steps.

As a result of performing the weather resistance evaluation of the deco film after 8000 hours as described above, as shown in FIG. 5 , the sheets of Examples 1 to 4 to which the supplementary coating layer containing the metal ion sequestering agent is applied is a sheet for a conventional deco film ( It was confirmed that the weather resistance was excellent compared to Comparative Examples 1 and 2). Specifically, in the case of the sheet of Comparative Example 1, when 5,000 hours (hr) elapsed, local surface defects such as brown spots occurred and discoloration progressed, which is It was found that the ions acted electrostatic force on Cl of PVC, weakening the C-Cl bonding, and lowering the weather resistance. In the case of the sheet of Comparative Example 2, the brown spot phenomenon first occurred when 7000 hours (hr) had elapsed, and it was confirmed that the weather resistance was excellent compared to Comparative Example 1, but the brown spot phenomenon still occurred. However, the sheets of Examples 1 to 4 prevent the metal ion sequestrant included in the complementary coating layer from weakening the C-Cl bonding by the electrostatic force acting on the Cl of PVC by the metal ion sequestering agent included in the complementary coating layer, as shown in FIG. , it was confirmed that local surface defects such as brown spots and discoloration did not occur until 8000 hours (hr) elapsed after the evaluation was completed, and good appearance was maintained.

400: base film layer
300: complementary coating layer
200: printed layer
100: transparent layer

Claims (11)

a base film layer comprising a polyvinyl chloride resin (PVC);
a complementary coating layer positioned on the base film layer;
a printed layer positioned on the complementary coating layer; and
a transparent layer positioned on the printed layer; and
Any one or more of the base film layer and the complementary coating layer contains metal ions,
The complementary coating layer is a weather resistance improvement sheet comprising a metal ion sequestering agent. The sheet for improving weather resistance according to claim 1, wherein the sequestering agent is a chelate agent. The sheet for improving weather resistance according to claim 1, wherein the chelate agent is at least one selected from the group consisting of EDTA, citrate, glycine, glyphosate and AMPA. The method of claim 1, wherein the metal ion is a ^{Ca 2 +, Cd 2 +,} Co 2 +, Cu 2 +, Fe 2 +, Fe 3 +, Mg 2 +, Mn 2+, Ni 2 + , and Zn ^{+ 2} A sheet for improving weather resistance, characterized in that at least one selected from the group consisting of. According to claim 1, wherein the base film layer further comprises a plasticizer, weather resistance improvement sheet. According to claim 1, wherein the thickness of the base film layer is characterized in that 80 to 400㎛, weather resistance improvement sheet. According to claim 1, wherein the metal ion sequestrant is characterized in that 0.1 to 5% by weight based on the total weight of the complementary film layer is included, weather resistance improvement sheet. According to claim 1, wherein the thickness of the complementary coating layer is characterized in that 1 to 20㎛, weather resistance improvement sheet. The sheet for improving weather resistance according to claim 1, wherein the transparent layer comprises an acrylic film. 10. The method of claim 9, wherein the acrylic film comprises an acrylate-based resin, acryl rubber particles having a core/shell structure, and further comprises any one or more of a radical scavenger and an antioxidant. , improved weatherability sheet. According to claim 1, wherein the thickness of the transparent layer is characterized in that 30 to 100㎛, weather resistance improvement sheet.

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