Flame-retardant interior film

Abstract

The present invention relates to a flame-retardant interior film having a structure in which an adhesive layer and a PVC substrate layer are laminated in this order, the PVC substrate layer containing at least one flame retardant selected from the group consisting of antimony oxide, silicate-based flame retardants, and metal hydroxide-based flame retardants, and the adhesive layer containing acrylic resin and antimony oxide.

Description

[Technical field]

[0001] The present invention relates to a flame-retardant interior film in which an adhesive layer and a base layer are laminated in this order, and more particularly to a flame-retardant interior film that includes a transparent adhesive layer and has excellent adhesiveness and flame retardancy. [Background technology]

[0002] Interior sheets are used for a variety of purposes, including decorations, signs, interior and exterior decorations, etc. The range of applications for interior films is continuing to increase, as they can be produced in a variety of ways regardless of design, allowing anyone to easily realize a variety of designs, and they can greatly improve the appearance at low cost.

[0003] Interior film is manufactured by laminating multiple layers such as adhesive layers and base layers, and polymer materials are preferred from the viewpoint of cost and processability. In particular, PVC material, which is widely used as interior film material, has a fast flame propagation speed when it catches fire and burns and generates toxic gases, so it is necessary to improve its flame retardancy in order to use it for interior decoration.

[0004] Meanwhile, interior film is used to improve the appearance by being attached to the surface indoors and outdoors, so it is constantly exposed to external factors such as humidity, temperature, and light. The PVC base layer and the adhesive layer have different expansion and deformation rates, so they repeatedly shrink and expand over time. In particular, the PVC base layer is made into the interior film in a stretched state during the manufacturing process, so it has a higher shrinkage rate than the adhesive layer. Therefore, after the interior film is installed, the PVC base layer shrinks, and the adhesive layer, which has a relatively small shrinkage rate, is exposed to the outside.

[0005] In the case of flame-retardant interior films, in order to enhance flame retardancy, flame retardants are added not only to the base layer but also to the adhesive layer, which gives the adhesive layer a color such as white.As mentioned above, if the colored adhesive layer becomes exposed due to shrinkage of the base layer after the interior film is installed, this can cause the problem of significantly impairing the appearance of the installed area.

[0006] In particular, this problem is more prevalent when installing interior films using a butt installation method in which the ends of the interior films are butted together so that they do not overlap, as opposed to an overlap installation method in which the ends of the interior films are installed so that they overlap each other, as this impairs the appearance.

[0007] In this regard, Patent Document 1 discloses a flame-retardant interior sheet including a foamed layer formed by adding a flame retardant to a PVC foamed layer and foaming it. However, the document only discloses an interior sheet to which a flame retardant has been added to impart flame retardancy, and does not at all acknowledge the problem of poor appearance caused by the exposure of the colored flame-retardant adhesive layer due to shrinkage of the base layer after application of the interior film.

[0008] Patent Document 2 relates to an adhesive composition for decorative sheets, which contains a (meth)acrylic acid ester copolymer and a flame retardant, but only discloses that it may contain various known flame retardants, and does not disclose at all the specific flame retardant components of a transparent adhesive layer having excellent flame retardancy and adhesion, or the amounts of each component added and the composition ratios.

[0009] Patent Document 3 discloses a non-flammable decorative sheet having an adhesive layer containing a thermoplastic resin sheet that is a polyvinyl chloride resin, an acrylic ester copolymer, a bromine-based flame retardant, antimony trioxide, and a tackifier, but does not disclose the necessity or specific configuration of a flame-retardant interior film that has a transparent adhesive layer with excellent flame retardancy and adhesion.

[0010] Therefore, there is a need for the development of a flame-retardant interior film that has improved flame retardancy, excellent adhesion, and a transparent adhesive layer that prevents damage to the appearance even after butt joint installation. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] Korean Patent Publication No. 10-2019-0070018 [Patent Document 2] Patent No. 6526725 [Patent Document 3] Patent No. 5271770 Summary of the Invention [Problem to be solved by the invention]

[0012] In conventional flame-retardant interior films, when the adhesive layer is exposed to the outside due to shrinkage of the base layer, a colored adhesive layer appears, which degrades the appearance of the applied area. The object of the present invention is to solve this problem.

[0013] An object of the present invention is to provide a flame-retardant interior film that has a transparent adhesive layer and yet has good flame retardancy. [Means for solving the problem]

[0014] The flame-retardant interior film of the present invention, which solves the above problems, has a structure in which an adhesive layer and a PVC base layer are laminated in that order, the PVC base layer contains one or more selected from the group consisting of antimony oxide, a silicate-based flame retardant, and a metal hydroxide-based flame retardant, and the adhesive layer contains an acrylic resin and antimony oxide.

[0015] In the present invention, the PVC base layer contains antimony oxide, the silicic acid-based flame retardant, and the metal hydroxide-based flame retardant, and the antimony oxide, the silicic acid-based flame retardant, and the metal hydroxide-based flame retardant may be contained in an amount of 10 to 50 parts by weight per 100 parts by weight of polyvinyl chloride contained in the PVC base layer.

[0016] In the present invention, the PVC substrate layer contains antimony oxide, the silicic acid-based flame retardant, and the metal hydroxide-based flame retardant. The metal hydroxide-based flame retardant and the silicic acid-based flame retardant are They may be added in a weight ratio of 1:1-5:0.2-3.

[0017] In the present invention, the antimony oxide and the silicic acid-based flame retardant may each be independently contained in an amount of 1 to 12.5 parts by weight per 100 parts by weight of polyvinyl chloride, and the metal hydroxide-based flame retardant may be contained in an amount of 1 to 25 parts by weight per 100 parts by weight of polyvinyl chloride.

[0018] In the present invention, the adhesive layer may contain 1 to 10 parts by weight of antimony oxide with respect to 100 parts by weight of the acrylic resin.

[0019] In the present invention, the adhesive layer may further contain a brominated flame retardant, and the adhesive layer may contain 10 to 30 parts by weight of the brominated flame retardant per 100 parts by weight of the acrylic resin.

[0020] In the present invention, the flame-retardant interior film may have a peel strength of 1.80 kg / in or more as measured in accordance with ASTM D3330.

[0021] In the present invention, the flame-retardant interior film has a total heat release (THR) value of 8.0 MJ / m2 as measured by a cone calorimeter measurement method in accordance with ISO 5660-1. 2 It may be the following.

[0022] In the present invention, the flame-retardant interior film may have a tensile strength of 15 to 30 MPa. Effect of the Invention

[0023] The flame-retardant interior film of the present invention has the advantage that even when the adhesive layer is exposed due to shrinkage of the base layer when the interior film is butted together for installation, the adhesive layer has transparency and does not deteriorate the appearance of the installed area.

[0024] The present invention has the effect of preventing deterioration in appearance that occurs over time after application of an interior film, while at the same time providing good flame retardancy.

[0025] The flame-retardant interior film according to the present invention has excellent adhesion and flame retardancy of the adhesive layer. [Brief description of the drawings]

[0026] [Figure 1] 1 is a schematic vertical cross-sectional view of a flame-retardant interior film according to an embodiment of the present invention. [Diagram 2] 1 is a vertical cross-sectional view showing a state in which a base layer of a conventional flame-retardant interior film is deformed due to shrinkage. [Diagram 3] FIG. 2 is a schematic plan view showing a state in which a conventional flame-retardant interior film is deformed due to shrinkage of the base material layer after being butt-fitted. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Hereinafter, each component of the present invention will be described in more detail so that a person having ordinary skill in the art to which the present invention pertains can easily implement the present invention. However, this is merely an example, and the scope of the present invention is not limited to the following content.

[0028] In order to impart flame retardancy to the interior film, a flame retardant is added to each of the constituent layers that make up the interior film.

[0029] Interior films are used with the aim of imparting an aesthetic feel by printing a desired design on the upper part of a base layer and providing an adhesive layer on the lower part of the base layer, and attaching the interior film to the desired location.

[0030] There are two methods for installing interior films: overlap installation, in which the outer edges of multiple interior films are installed so that they overlap each other, and a butt installation method, in which the outer edges of the interior films are installed so that they do not overlap each other and the ends of the interior films are butted together.

[0031] The flame-retardant adhesive layer that makes up the flame-retardant interior film is not transparent but has a color such as white. When the films are overlapped, the adhesive layer is not exposed to the outside. However, when the films are butt-attached, the individual layers of the interior film shrink at different rates depending on the room temperature and humidity, causing only the adhesive layer to be exposed to the outside, which causes a problem in the appearance.

[0032] Specifically, referring to FIG. 2, which is a vertical cross-sectional view showing the deformation caused by shrinkage of the base layer of a conventional flame-retardant interior film, and FIG. 3, which is a plan view, the PVC base layer is stretched by a calendaring process and then laminated with an adhesive layer to produce an interior film.

[0033] The PVC base layer 21 is laminated with the adhesive layer 11 in a stretched state by a calendaring process to produce a flame-retardant interior film 101, which is then applied to the attachment surface 1. As time passes after application, the stretched PVC base layer 21 shrinks and transforms into a shrunken PVC base layer 21'.

[0034] The adhesive layer 11, which has a relatively small shrinkage rate and is supported in an adhered state to the adherend surface 1, is maintained without shrinking significantly from its original shape, and the adhesive layer 11 below the shrunk PVC base layer 21' is exposed to the outside.

[0035] The adhesive layer 11 constituting the flame-retardant interior film 101 is colored due to the inclusion of a flame retardant. Therefore, after the flame-retardant interior film 101 is installed, the PVC base layer 21 shrinks, causing the colored adhesive layer 11 to become visible, resulting in a problem of a reduced aesthetic appearance.

[0036] The present invention is intended to solve the above-mentioned problems, and provides a flame-retardant interior film in which, even if the adhesive layer becomes exposed due to deformation such as shrinkage of the base material layer after butt joint construction, the adhesive layer is configured to be transparent so that the aesthetic appearance of the interior film is not marred, and at the same time, as a flame-retardant interior film, it has excellent adhesive properties in terms of the adhesive layer and the flame retardancy of the interior film itself.

[0037] Hereinafter, each component of the flame-retardant interior film according to the present invention will be described in more detail. However, this is merely an example for understanding the technical concept of the present invention, and the scope of the present invention is not limited by the following description.

[0038] PVC base material layer The PVC base layer containing polyvinyl chloride is produced in a film shape stretched by a calendaring process during processing, and is laminated with an adhesive layer in a stretched state, which causes the base layer to naturally shrink over time, which can cause a problem that the adhesive layer appears in an adhered state on the adherend surface.

[0039] When an interior film containing a stretched polyvinyl chloride base layer and an adhesive layer as described above is installed using the butt-fit installation method, the ends of the stretched base layer are attached so as to butt against each other at the time of installation. However, over time or in response to environmental changes (temperature, humidity, etc.) around the installation area, the stretched base layer shrinks, causing a problem in that the lower adhesive layer is exposed to the outside.

[0040] Since the flame-retardant adhesive layer of the flame-retardant interior film is colored, there has been a problem in that shrinkage of the base layer causes the colored flame-retardant adhesive layer to become exposed, significantly degrading the appearance.

[0041] This is because the flame-retardant adhesive layer becomes opaque when an excessive amount of flame retardant is added in order to ensure a desired level of flame retardancy.

[0042] The present invention is intended to solve such problems, and aims to solve the problem of appearance damage that occurs when butting together interior films by introducing an adhesive layer of the above-mentioned composition, as described above, and by introducing a transparent adhesive layer that has excellent adhesion and good flame retardancy.

[0043] Specifically, in the present invention, the PVC substrate layer contains polyvinyl chloride and a flame retardant, which contains polyvinyl chloride to produce a material having the shape and predetermined strength of the substrate layer, and contains at least one selected from the group consisting of antimony oxide, silicic acid-based flame retardants, and metal hydroxide-based flame retardants to impart flame retardancy.

[0044] The PVC substrate layer is prepared in a layered form using a PVC substrate layer-forming composition, for example, a substrate layer-forming composition including polyvinyl chloride, an organic flame retardant, an inorganic flame retardant, an auxiliary flame retardant, a plasticizer, a heat-resistant plasticizer, a stabilizer, a processing aid, an impact modifier, etc. may be applied to form the substrate layer.

[0045] The base layer may have a thickness of 50 to 150 μm (micrometers), and preferably has a thickness of 80 to 150 μm (micrometers).

[0046] If the thickness is thinner than the above range, the strength of the flame-retardant interior film will be reduced, making it unsuitable for use as an interior film, and if the thickness is thicker than the above range, it will be difficult to apply to curved areas.

[0047] The PVC substrate layer may contain antimony oxide, a silicic acid-based flame retardant, and a metal hydroxide-based flame retardant, and the antimony oxide, the silicic acid-based flame retardant, and the metal hydroxide-based flame retardant may be contained in an amount of 10 to 50 parts by weight per 100 parts by weight of polyvinyl chloride.

[0048] If an amount exceeding the above-mentioned content is added, the viscosity of the base layer-forming composition increases, making it difficult to process the composition into a layer. In addition, the transparency of the adhesive layer decreases, resulting in the same problem as in the past, in that the appearance is impaired when the adhesive layer is exposed to the outside.

[0049] The above-mentioned range of the total content of the flame retardants is satisfied, and each of the flame retardants is added so as to satisfy the above-mentioned content ratio.

[0050] More specifically, the antimony oxide, The metal hydroxide-based flame retardant and the silicic acid-based flame retardant are They may be added in a weight ratio of 1:1-5:0.2-3.

[0051] Preferably, they may be added in a weight ratio of 1:1-4.5:0.4-1.2.

[0052] If the silicic acid-based flame retardant is added in an amount greater than the above ratio, there are problems such as increased production costs, decreased film strength, and decreased processability. If the silicic acid-based flame retardant is added in an amount less than the above ratio, there are problems such as decreased flame retardant performance due to high heat release.

[0053] On the other hand, if the metal hydroxide flame retardant is added in an amount greater than the above ratio, there is a problem that the viscosity of the composition for forming the PVC base layer increases, making it difficult to form the composition into a film, and there is a problem that the shrinkage rate of the base layer increases with temperature changes during the production of the interior film, resulting in a deterioration in the quality of the interior film. If the metal hydroxide flame retardant is added in an amount less than the above ratio, there is a problem that the flame retardant performance decreases.

[0054] On the other hand, the antimony oxide may be specifically antimony trioxide (Sb2O3), antimony pentoxide (Sb2O5), etc., and preferably antimony trioxide.

[0055] Antimony trioxide is a white, odorless powder that is mainly used as a flame retardant for plastics, polyester polymerization catalyst, and a clarifying agent for removing bubbles in the glass manufacturing process. Antimony trioxide for flame retardant use can be added in an appropriate ratio with halogen-based flame retardants depending on the type of plastic to increase the flame retardant effect.

[0056] Specifically, antimony oxide helps chlorine radicals formed in the PVC substrate layer to capture OH and H radicals to prevent combustion. When a PVC resin is used as in the present invention, the antimony oxide retains halogen radicals to maintain or strengthen the flame retardant performance, preventing the chlorine radicals generated by the combustion of the PVC substrate layer from easily scattering into the air and reducing the flame retardant performance, thereby improving the flame retardancy of the PVC substrate layer.

[0057] In the present invention, the antimony oxide may be contained in an amount of 1 to 12.5 parts by weight based on 100 parts by weight of the polyvinyl chloride.

[0058] The silicic acid-based flame retardant is a silicate compound, and may include, for example, a silicate compound such as sodium silicate, calcium silicate, or magnesium silicate.

[0059] The silicic acid-based flame retardant forms a glass film on the carbonized film formed during combustion, strengthening the carbonized film and preventing active radicals that induce combustion from contacting the dematerialized material, thereby preventing combustion. In the present invention, the silicic acid-based flame retardant may be included in an amount of 1 to 12.5 parts by weight based on 100 parts by weight of the polyvinyl chloride.

[0060] Meanwhile, the metal hydroxide-based flame retardant means a metal hydroxide salt, and for example, magnesium hydroxide, aluminum hydroxide, calcium hydroxide, and other flame retardants can be used.

[0061] The metal hydroxide flame retardant generates water during combustion to lower the temperature of the combustion site, thereby preventing combustion and improving the flame retardant performance. In the present invention, the metal hydroxide flame retardant may be included in an amount of 1 to 25 parts by weight based on 100 parts by weight of the polyvinyl chloride.

[0062] However, the above-mentioned amounts of each type of flame retardant added within the range of the total content and addition ratio of the flame retardants contained in the PVC base layer are merely examples, and the actual amount added may be appropriately within the above ratio range within the range of the total content and addition ratio.

[0063] The present invention provides a flame-retardant interior film that maximizes the flame retardant performance of the PVC base layer by simultaneously adding the above-mentioned flame retardants in a prescribed content and ratio.

[0064] In addition to the flame retardant, the PVC substrate layer may further include other components such as a plasticizer and a heat stabilizer.

[0065] In the case of other components, they can be added in appropriate amounts as required.

[0066] Specifically, the plasticizer may be, for example, a phthalate-based plasticizer, an adipate-based plasticizer, a trimellitate-based plasticizer, or an ester-based plasticizer.

[0067] The heat stabilizer may be a Cd / Ba / Zn-based heat stabilizer, a Cd / Ba-based heat stabilizer, a Ba / Zn-based heat stabilizer, a Ca / Zn-based heat stabilizer, a Na / Za-based heat stabilizer, a Sn-based heat stabilizer, a Pb-based heat stabilizer, a Cd-based heat stabilizer, a Zn-based heat stabilizer, etc., and the impact modifier may be an MBS impact modifier, an acrylic impact modifier, etc. It is not necessary to use only one of each component, and one or more appropriate components may be used as necessary.

[0068] However, since the above-mentioned components are not essential components, the base layer can be formed by adding other additional components as necessary or without the above-mentioned components without departing from the scope of the present invention.

[0069] Polyvinyl chloride The polyvinyl chloride is a type of thermoplastic plastic that is excellent in processability and durability, but has a weak property against heat. In the present invention, a flame retardant is added to the polyvinyl chloride to form the base layer, thereby compensating for the shortcoming of polyvinyl chloride against heat.

[0070] Meanwhile, the polyvinyl chloride is an additive polymer polymerized using vinyl chloride as a monomer, and in the present invention, it is preferable to use polyvinyl chloride having a degree of polymerization in the range of 500 to 2000. More preferably, polyvinyl chloride having a degree of polymerization of 800 to 1200 can be used.

[0071] When polyvinyl chloride having a degree of polymerization higher than the above range is used, there are problems in that it is difficult to process and is too hard, and when polyvinyl chloride having a degree of polymerization lower than the above range is used, there are problems in that durability and processing stability are reduced.

[0072] adhesive layer The adhesive layer includes an acrylic resin and antimony oxide, and contains an acrylic resin to impart adhesion to the adhesive layer, and a flame retardant to impart flame retardancy, and contains antimony oxide.

[0073] The adhesive layer is formed in a layer shape using an adhesive layer-forming composition. For example, the adhesive layer may be formed by applying an adhesive layer-forming composition including an acrylic resin, a flame retardant, a solvent, a curing agent, and a tackifier.

[0074] The adhesive layer may have a thickness of 20 to 60 μm (micrometers), and preferably has a thickness of 30 to 50 μm (micrometers).

[0075] If the thickness is thinner than the above range, there is a problem in that the adhesive properties are inferior, and if the thickness is thicker than the above range, there is a problem in that when the adhesive layer-forming composition is applied in a layer form, curing is slow and it is difficult for the adhesive layer to maintain sufficient strength and adhesiveness.

[0076] The adhesive layer may contain 1 to 10 parts by weight of antimony oxide based on 100 parts by weight of the acrylic resin.

[0077] The adhesive layer-forming composition for forming the adhesive layer may contain 1 to 10 parts by weight of antimony oxide, 100 to 200 parts by weight of a solvent, 0.1 to 10 parts by weight of a curing agent, and 1 to 15 parts by weight of a tackifier, relative to 100 parts by weight of the acrylic resin.

[0078] Specifically, the solvent is, for example, toluene, xylene, ethyl acetate (EAc), methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), etc., and a mixed solvent obtained by mixing appropriate solvents with each other can be used as necessary.

[0079] On the other hand, the curing agent can be any type as long as it can form the pressure-sensitive adhesive-forming composition into an adhesive layer and can function as a curing agent by reacting with the acrylic resin. For example, it may be an epoxy-based, chelate-based, melamine-based, isocyanate-based, aziridine-based, or oxazoline-based curing agent, and one or more types of curing agents may be used in combination as necessary.

[0080] The tackifier is a component added to enhance the adhesive strength of the adhesive layer, and can improve the adhesive strength, and can be used without any particular limitation as long as it is used in the relevant technical field. For example, rosin ester, terpene phenol, petroleum-based C6 resin, petroleum-based C9 resin, etc., and one or more suitable tackifiers can be used in combination as necessary.

[0081] In the flame-retardant interior film according to the present invention, the adhesive layer may have a light transmittance of 70% or more, and preferably 75% or more.

[0082] If the transmittance is lower than the above range, when the adhesive layer is exposed due to shrinkage of the base layer as intended by the present invention, the color of the adhesive layer significantly impairs the appearance.

[0083] This can cause a problem in that the appearance is significantly deteriorated due to the color of the adhesive layer being exposed, particularly when the interior film is installed by butt-joint installation as described above.

[0084] Acrylic Resin The acrylic resin can be used without any particular limitation as long as it is capable of forming an adhesive layer and has sufficient adhesive strength so as to function as an interior film.

[0085] The acrylic resin means a pressure-sensitive adhesive obtained by polymerizing acrylate and methacrylate monomers. For example, the acrylic resin may contain a functional group such as a hydroxyl group or a carboxyl group, such as a hydroxyalkyl (meth)acrylate, or may be a copolymer of a nitrogen-containing (meth)acrylic ester monomer.

[0086] The acrylic resin may have a solid content of 5 to 50%, preferably 10 to 45%.

[0087] If the solids content is more than the above-mentioned content, there is a problem that the viscosity of the adhesive increases significantly, making it difficult to apply, and if the solids content is less than the above-mentioned content, there is a problem that it is difficult to use it to form an adhesive layer of a certain thickness or more.

[0088] Antimony Oxide Conventional flame retardants added to the adhesive layer of flame-retardant interior films make the adhesive layer opaque, which causes problems such as the substrate layer shrinking due to changes in the external environment or the opaque adhesive layer being exposed when the interior film is removed after use, marring the appearance.

[0089] Adhesive layers that are primarily opaque or white in color have problems that arise when the content of inorganic flame retardant is excessive, and problems that arise when the content of inorganic flame retardant is significantly reduced, in that sufficient flame retardancy cannot be ensured.

[0090] In order to solve these problems, the object of the present invention is to simultaneously ensure the adhesiveness and flame retardancy of the adhesive layer while ensuring the transparency of the adhesive layer and maintaining the original function of the flame-retardant interior film.

[0091] As a result, the adhesive layer of the flame-retardant interior film according to the present invention contains a predetermined content of antimony oxide so as to maintain the transparency of the adhesive layer, and the PVC base layer contains predetermined contents of antimony oxide, silicate-based flame retardant and metal hydroxide-based flame retardant, thereby providing an interior film with a transparent adhesive layer and excellent flame retardancy.

[0092] Specifically, the antimony oxide can refer to the composition of the antimony oxide added to the PVC substrate layer. The antimony oxide contained in the adhesive layer may be the same as or different from the antimony oxide in the PVC substrate layer.

[0093] The adhesive layer contains antimony oxide, so that the transparency and flame retardancy of the adhesive layer can be ensured at the same time. For example, when an inorganic flame retardant other than antimony oxide is used, there is a problem that it is difficult to ensure sufficient flame retardancy by adding only a small amount, and when another inorganic flame retardant is used in the same amount or in an excessive amount, there is a problem that it is difficult to ensure the transparency of the adhesive layer, or the viscosity of the adhesive layer-forming composition for forming the adhesive layer is high, resulting in a decrease in coatability.

[0094] The content of the antimony oxide in the adhesive layer of the flame-retardant interior film according to the present invention may be 1 to 10 parts by weight, preferably 2 to 8 parts by weight, based on 100 parts by weight of the acrylic resin.

[0095] If an amount exceeding the above-mentioned content is added, the viscosity of the adhesive layer-forming composition increases, which can cause problems such as difficulty in processing the composition into a layer, and the transparency of the adhesive layer decreases, which can cause problems such as poor appearance when the adhesive layer is exposed to the outside.

[0096] If the content is less than the above range, there is a problem that sufficient flame retardancy cannot be ensured.

[0097] Other flame retardants In addition to antimony oxide, the adhesive layer may contain other flame retardants to improve flame retardancy.

[0098] Examples of flame retardants that can be added include halogen-based flame retardants, and preferably bromine-based flame retardants.

[0099] When the brominated flame retardant is added, there is an advantage that the adhesive strength of the adhesive layer is not reduced and the transparency can be maintained.

[0100] The other flame retardants can be used without any particular restrictions as long as they are known flame retardants, but since the adhesive layer contained in the interior film of the present invention must be excellent in flame retardancy and adhesiveness as well as transparent, they can be appropriately added within a range that does not reduce these properties.

[0101] In particular, the other flame retardants refer to all other flame retardants except antimony oxide added to the adhesive layer, and can be appropriately added within the scope of the present invention, regardless of whether they are additive flame retardants, reactive flame retardants, inorganic flame retardants, organic flame retardants, etc.

[0102] For example, the organic flame retardant may include a phosphorus-based flame retardant, a nitrogen-based flame retardant, a halogen-based flame retardant, a bromine-based flame retardant, etc. However, the inorganic flame retardant other than the antimony oxide added to the adhesive layer is called other flame retardant, and may be added within the scope of the present invention.

[0103] In detail, the adhesive layer further contains a brominated flame retardant as another flame retardant, and the brominated flame retardant can be added in an amount of 10 to 30 parts by weight per 100 parts by weight of the acrylic resin.

[0104] Similar to the adhesive layer, the PVC substrate layer may further include other flame retardants that can improve the flame retardancy.

[0105] Other flame retardants in the PVC base layer can be used without any particular restrictions as long as they are known flame retardants, and unlike the adhesive layer, there is no restriction such as having to satisfy transparency in addition to flame retardancy, so they can be added as appropriate without restrictions on type within the scope of the object of the present invention.

[0106] Therefore, in the case of the other flame retardants in the PVC substrate layer, the content is not particularly limited, but may be added in various amounts within a range in which the physical properties required for the substrate layer are not deteriorated, such as the substrate layer being unable to be formed in a calendaring process due to deterioration of the physical properties of the substrate layer-forming composition, or the rigidity being reduced.

[0107] The other flame retardants refer to all flame retardants other than the antimony oxide, silicic acid-based flame retardants, and metal hydroxide-based flame retardants in the PVC substrate layer, and can be appropriately added within the range intended by the present invention, regardless of whether they are additive flame retardants, reactive flame retardants, inorganic flame retardants, organic flame retardants, etc.

[0108] For example, the organic flame retardant may include a phosphorus-based flame retardant, a nitrogen-based flame retardant, a halogen-based flame retardant, a bromine-based flame retardant, etc., and the inorganic flame retardant may include a metal compound or an inorganic phosphorus-based flame retardant.

[0109] others The flame-retardant interior film according to the present invention may include additional layers without departing from the scope of the present invention. The additional layers, such as a printing layer and a surface coating layer, may be configured in various ways.

[0110] The present invention aims to solve the problems that occur after butt joint installation of conventional flame-retardant interior films, and it is also possible to add additional layers and additives, etc., within the range that satisfies the original functions of flame-retardant interior films, such as adhesion and flame retardancy.

[0111] Specifically, the flame-retardant interior film according to the present invention has a peel strength of 1.80 kg / in or more as measured in accordance with ASTM D3330, and a total heat release (THR) value of 8.0 MJ / m2 as measured by a cone calorimeter method in accordance with ISO 5660-1. 2 It is characterized by satisfying the following:

[0112] The peel force corresponds to a level of physical properties suitable for commercialization as an interior film product, and the flame retardant performance meets the standards for commercialization as a flame-retardant interior film product. The flame-retardant interior film of the present invention is characterized in that the transparent adhesive layer has sufficient adhesion and is flame-retardant.

[0113] Furthermore, the flame-retardant interior film according to the present invention may have a tensile strength of 15 to 30 MPa, preferably 20 to 25 MPa.

[0114] When the above range is satisfied, the film can be considered to have the flexibility and durability required for an interior film, and the physical properties are attributable to the physical properties of the PVC base layer of the interior film. EXAMPLES

[0115] Hereinafter, the embodiments of the present invention will be described in detail so that a person having ordinary skill in the art to which the present invention pertains can easily implement the present invention. However, this is merely an example, and the scope of the present invention is not limited to the following content.

[0116] [Production Example] Interior films were manufactured based on Tables 1 and 2 below.

[0117] The substrate layer was prepared by mixing a composition containing polyvinyl chloride, and then producing a film-like stretched polyvinyl chloride substrate layer having a thickness of 100 μm (micrometers) by a calendaring method.

[0118] A transparent PVC film was laminated onto one surface of the thus-produced substrate layer to produce a laminate.

[0119] An acrylic resin in which butyl acrylate, 2-ethylhexyl acrylate, methyl acrylate and acrylic acid were copolymerized was mixed with ethyl acetate as a solvent, and a flame retardant was added.

[0120] The composition was coated on a release paper and dried for 3 minutes at 110° C. to prepare a flame-retardant adhesive layer, which had a thickness of about 35 μm (micrometers) after drying.

[0121] The produced adhesive layer and the laminate were laminated to produce an interior film.

[0122] [Table 1]

[0123] [Table 2]

[0124] [Experimental Example] The produced interior film was evaluated for physical properties as follows, and the results are shown in Table 3.

[0125] 1. Light transmittance test of adhesive layer The adhesive layer prepared in the above Preparation Example was coated on a transparent PET film, and the transmittance of the adhesive was measured.

[0126] The transmittance was evaluated by irradiating light with a wavelength of 550 nm using Haze-gard plus (manufacturer: BYK Gardner GmbH / AB NEXO).

[0127] 2. Measurement of total heat release The flame retardant performance of the interior film was evaluated according to the cone calorimeter measurement method (ISO-5660-1).

[0128] Each interior film was prepared as a standard sample and then evaluated. The total heat release for each interior film was 8.0MJ / m 2 If it is less than 7.2MJ / m, it is considered "good". 2 If it is below, it is rated as "Excellent".

[0129] 3. Peeling force In accordance with ASTM D3330, the interior film was attached to a SUS substrate (2 kg, 5 round trips), and then peeled off at a speed of 300 mm / min to measure the peel strength.

[0130] 4. Tensile strength The tensile strength was measured using a tensile strength tester (device name, company name).

[0131] [Table 3]

[0132] Referring to Table 3, it can be seen that the adhesive layer of the examples is transparent and has excellent adhesive strength as well as excellent tensile strength of the interior film itself compared to the comparative examples.

[0133] Specifically, in the case of Comparative Examples 7 and 11, the transparency of the adhesive layer was poor, and as a result, the problem that the present invention aims to solve is that after the interior film is butted and installed, when the PVC base layer shrinks due to changes in the installation environment over a long period of time (such as temperature changes and humidity changes), the adhesive layer becomes exposed, and the opaque color of the adhesive layer is exposed to the outside, damaging the appearance.

[0134] On the other hand, in the case of Comparative Examples 1 to 4, it can be seen that the adhesive layer has a high light transmittance and is therefore transparent, but in contrast, it can be seen that the total heat release of the interior film is high and the flame retardant properties are significantly inferior.

[0135] It can be seen that Comparative Examples 5 and 9 have the lowest adhesive strength, but this is because the adhesive layer contains an excessive amount of curing agent and tackifier, which results in poor adhesiveness.

[0136] In the cases of Comparative Examples 6 and 10, it can be seen that the tensile strength is low, which is due to the fact that an excessive amount of solids is added to the substrate layer, which results in a significant deterioration in the flexibility of the substrate layer constituting the interior film.

[0137] In this way, it can be confirmed that the flame-retardant interior film of the examples has a transparent adhesive layer, making it suitable for use in butt joint construction, has excellent adhesion of the adhesive layer and flame retardancy of the flame-retardant interior film itself, and meets the tensile properties required of an interior film.

Claims

1. It has a structure in which an adhesive layer and a PVC base layer are laminated in this order, The PVC substrate layer contains antimony oxide, a silicic acid-based flame retardant, and a metal hydroxide-based flame retardant, The adhesive layer contains an acrylic resin, an antimony oxide, a curing agent, a bromine-based flame retardant, and a tackifier, The antimony oxide, the metal hydroxide-based flame retardant, and the silicic acid-based flame retardant of the PVC substrate layer are added in a weight ratio of 1:1 to 4.5:0.4 to 1.2; The antimony oxide of the PVC substrate layer is contained in an amount of 1 to 12.5 parts by weight per 100 parts by weight of polyvinyl chloride, The adhesive layer contains, relative to 100 parts by weight of the acrylic resin, 0.1 to 2 parts by weight of the curing agent, 10 to 20 parts by weight of the bromine-based flame retardant, 1 to 10 parts by weight of the antimony oxide, and 1 to 5 parts by weight of the tackifier.

2. A flame-retardant interior film as described in claim 1, wherein the antimony oxide, the silicate-based flame retardant and the metal hydroxide-based flame retardant are contained in an amount of 10 to 50 parts by weight per 100 parts by weight of polyvinyl chloride contained in the PVC base layer.

3. A flame-retardant interior film as described in claim 1, wherein the silicate-based flame retardant is contained in an amount of 1 to 12.5 parts by weight per 100 parts by weight of polyvinyl chloride, and the metal hydroxide-based flame retardant is contained in an amount of 1 to 25 parts by weight per 100 parts by weight of polyvinyl chloride.

4. The flame-retardant interior film is The total heat release (THR) value measured by the cone calorimeter measurement method in accordance with ISO 5660-1 is 8.0 MJ / m 2 2. The flame-retardant interior film of claim 1, wherein:

5. A flame-retardant interior film as described in claim 1, wherein the adhesive layer has a light transmittance of 70% or more.

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