WO2020004828A1 - High-hardness laminate - Google Patents

Abstract

Disclosed is a laminate having high hardness and excellent shape conformity, which may be used as a three-dimensional cover substrate of a display or as a device substrate. The laminate comprises: a substrate (10); a hard coating layer (20) on one side of the substrate (10); and a double-sided adhesive film (30) on the other side of the substrate (10), wherein the double-sided adhesive film (30) includes a base substrate (31) and adhesive layers (32), one each disposed on each side of the base substrate (31), wherein at least one of the adhesive layers (32) contains a silicone-based compound.

Description

High hardness laminate

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high hardness laminate, and more particularly, to a laminate having high hardness and excellent moldability that can be used as a three-dimensional cover substrate or element substrate of a display.

Recently, with the development of mobile devices such as smartphones and tablet PCs, thinning and slimming of the display base material are required. Glass or tempered glass is generally used as a material having excellent mechanical properties in the display window or the front plate of the mobile device. Glass is transparent and hard but fragile. It does not dissolve in water and does not change. It resists heat well, but is weak to sudden changes in temperature. It is also easy to make or process shapes. Because of these properties, glass is used in a wide variety of buildings, objects, and products, making it difficult to stay in contact with everyday life. It is widely used in high-tech products such as building glass, smartphones, flat-screen TVs and automobiles. However, because of its fragile nature, it requires a lot of restrictions and attention to storage and use. Tempered glass has been developed to improve this, but the mobile device due to the weight of the glass itself causes a high weight, and the original characteristics of cracking are not completely complemented.

Plastics have been studied as a substitute for glass. Plastic resin film is suitable for the trend toward the lighter mobile device because it is transparent like glass, easy to process, light and hard to break. However, there are limitations in replacing glass due to low surface hardness and weak wear. Films and sheets for coating a hard coating layer made of a plastic resin on a supporting substrate have been studied to produce a film having high hardness and wear resistance.

As a method of improving the surface hardness and wear resistance of the hard coating layer, a method of increasing the thickness of the hard coating layer may be considered. In order to secure the surface hardness to replace the glass it is necessary to implement a constant thickness of the hard coating layer. However, as the thickness of the hard coating layer is increased, the surface hardness may be increased. However, since the wrinkles and warpage increase due to shrinkage and expansion of the substrate and shrinkage and expansion of the hard coating layer, the hard coating layer is likely to be cracked or peeled off. It is not easy to apply.

On the other hand, due to the development of display technology, a portion of the edge of the display device is curved, or a display having a curved three-dimensional shape as a whole has recently attracted attention. This trend is especially prominent in mobile devices such as smartphones and tablet PCs. In addition, home appliances such as automobile dashboard integrated display systems, washing machines with built-in display functions, and refrigerators are being developed. In the case of using tempered glass as an exterior material for protecting such a three-dimensional display, even if the tempered glass is used, there is a high risk of breakage due to its high weight and weak characteristics against external impact.

Plastic has the advantage of being lighter than glass and not easily broken by external impacts and fragments being scattered, but it is difficult to manufacture films and sheets having a three-dimensional structure and high hardness properties such as glass.

In particular, when performing thermoforming using a mold in order to mold the film into a three-dimensional shape, there is a problem that deformation or cracking occurs due to high temperature heat and compression shock caused by the mold. OCA (Optically clear adhesive) film used as a conventional double-sided adhesive film (AB film) has a problem that deterioration or deformation occurs during thermoforming, so that the quality of the product is degraded, an adhesive having a heat resistance is required.

Therefore, it is an object of the present invention to provide a laminate having high hardness and preventing cracks and excellent in formability.

The present invention, in order to achieve the above object, 10; A hard coating layer 20 disposed on one surface of the substrate 10; And a double-sided pressure-sensitive adhesive film 30 positioned on the other side of the substrate 10, wherein the double-sided pressure-sensitive adhesive film 30 is attached to each of the support base material 31 and the support base material 31, respectively. 32), wherein any one or more of the adhesive layers 32 provide a laminate comprising a silicon-based compound.

The present invention also provides a silicone pressure sensitive adhesive composition comprising a silicone polymer, silicone resin, crosslinking agent, solvent and platinum catalyst.

According to the present invention, it is possible to provide a laminate having a three-dimensional structure including a curved surface having high hardness and little cracking.

In addition, the laminate according to the present invention can be usefully applied to cover plates of mobile devices, display devices, front panels of various instrument panels, display panels, etc. of various shapes as well as flat conventional displays by replacing cover plates made of glass or tempered glass. Can be.

1 is a cross-sectional view for explaining the structure of a laminate according to one embodiment of the present invention.

Figure 2 is a cross-sectional view for explaining the structure of a laminate according to another embodiment of the present invention.

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

1 is a cross-sectional view for explaining the structure of a laminate according to one embodiment of the present invention. As shown in Figure 1, the laminate of the present invention, the substrate 10; A hard coating layer 20 disposed on one surface of the substrate 10; And a double-sided pressure-sensitive adhesive film 30 positioned on the other side of the substrate 10, wherein the double-sided pressure-sensitive adhesive film 30 is positioned on both sides of the support base 31 and the support base 31, respectively. ), And at least one of the adhesive layers 32 includes a silicon-based compound.

The glass transition temperature (Tg) of the substrate 10 is 80 ° C to 300 ° C, preferably 90 ° C to 180 ° C. If the glass transition temperature (Tg) of the substrate 10 is lower than 80 ° C., the thermal stability may be low, causing problems of warpage, warpage or dimensional change of the substrate 10. When the glass transition temperature (Tg) of the substrate 10 is higher than 300 ° C., the appearance defects such as pressing marks, stain marks, etc. due to the mold may be generated on the surface of the hard coating layer 20, and the product yield may be lowered. .

If the base material 10 having the glass transition temperature (Tg) in the above range can be used without particular limitation in the production method or material of the base material 10, such as a stretched film or a non-stretched film. The substrate 10 may include a polyester such as polyethylene terephthalate (PET), a cyclic olefin polymer (COP), a cyclic olefin copolymer (COC), polyacryl Polyacrylate (PAC), polycarbonate (PC), polymethylmethacrylate (PMMA), polyethylene (PE), polyetheretherketone (PEEK), polyethylenenaphthalate (PEN) ), Polyetherimide (PEI), polyimide (PI), colorless and transparent polyimide (CPI), triacetylcellulose (TAC), thermoplastic polyurethane elastomer (TPU) Etc. can be used. The substrate 10 may be a single layer or a multilayer structure including two or more layers made of the same or different materials as necessary, but is not particularly limited. Although the thickness of the base material 10 is not particularly limited, in consideration of the processability for the three-dimensional shape it is good to select a range of 30㎛ to 2,000㎛.

The hard coating layer 20 is formed by applying a hard coating composition to the substrate 10. The hard coating composition may include one or more of known silsesquioxanes, siloxane compounds, silicone compounds, acrylic compounds, melamine compounds, urethane compounds, and organic-inorganic hybrid type hard coating compositions.

In particular, Silsesquioxane (SSQ) is an organic-inorganic hybrid material, which is 1: 1.5, which is an intermediate between a solid Si: O mole ratio of silica (SiO 2) and a flexible polysiloxane (SiOR 2) n, and is represented by a chemical formula (SiO). _1.5 R) n (R is hydrogen, alkyl having 1 to 10 carbon atoms, aryl, cycloalkyl or glycidyl group, n is an integer of 3 to 20.) Ladder-type polysilsesquioxane Ladder is a linear structure in which silanol groups (-SiOH) exist only at the ends, unlike conventional random structures of sol. It has a feature of excellent heat resistance, mechanical properties, high light transmittance, etc. by a backbone (main chain) of silica structure, has been spotlighted as a hard coating material.

The method of applying the coating solution to the substrate 10 may be slit coating, flow coating, comma coating, bar coating, curtain coating, slot die coating, etc., and the hard coating layer 20 may have a thickness of 1 μm to 50 after curing. Μm, preferably 5 μm to 45 μm. If the thickness of the hard coating layer 20 is less than 1㎛ high hardness characteristics can not be obtained, the wear resistance is poor scratch may easily occur. When the thickness of the hard coating layer 20 exceeds 50㎛, a high level of hardness can be obtained, but the mechanical strength is so strong that a crack may occur in the curved portion during the thermoforming process, or the radius of curvature of the curved portion may increase. . In addition, in order to reduce defects due to cracking and to improve adhesion of the curved portion, a cutting process before thermoforming may be performed, which may cause a problem in that product yield is lowered. For example, in a high-speed computerized numerical control (CNC) process, cracks occur and yields drop sharply, and a single-edged cutting tool for a machine tool such as a lathe planer is replaced. Shorter cycles can increase costs. Meanwhile, in the laser process, warpage may occur due to damage due to an increase in laser power.

The double-sided adhesive film 30 includes a support base 31 and an adhesive layer 32 formed on both sides of the support base 31, respectively, and the substrate 10 or the UV coating layer 50 and the surface of the display. It serves to attach. The pressure-sensitive adhesive composition used in the pressure-sensitive adhesive layer 32 is not particularly limited, but may include any one or more selected from rubber compounds, acrylic compounds, silicone compounds, urethane compounds, and organic-inorganic hybrid compounds.

In detail, the rubber compound may be a butyl compound, but may include styrene-butadiene, polybutadiene, butadiene containing a hydroxy group, and the like. N-butyl acrylate, methyl acrylate, hydroxyethyl Polyacrylate copolymerized from methacrylate, polymethyl acrylate, polydimethyl (meth) acrylate and acrylic acid, etc. may be used, and the silicone compound may be a silicone polymer, silicone resin, or the like. As the polyurethane and polyurethane acrylate can be used, the organic-inorganic hybrid type compound may be used, such as polyurethane containing fluorine, polyurethane containing hydroxy and silyl acrylate, etc. Type of adhesive composition according to the characteristics It may be at the ratio of monomer.

The double-sided adhesive film 30 may be attached to the substrate 10 or the UV coating layer 50 and then subjected to a thermoforming process. At this time, the composition forming the pressure-sensitive adhesive layer 32 of the double-sided pressure-sensitive adhesive film 30 uses a composition having heat resistance to prevent modification and deformation in the thermoforming process. If the heat-resistant temperature of the composition constituting the adhesive layer 32 is too low, the pressure-sensitive adhesive decomposes during thermoforming and bubbles may be generated or melted to contaminate the thermoforming mold when severe, so that the composition constituting the adhesive layer 32. In consideration of the thermoforming temperature, it is preferable to use one similar to the glass transition temperature (Tg) range of the substrate 10.

Since the silicone-based compound has heat resistance characteristics, when applied to the adhesive layer 32, the silicone compound serves to prevent cracking of the cured adhesive layer 32 during thermoforming after curing. In addition, on the basis of such heat resistance characteristics, it is possible to improve bubble defects appearing during thermoforming and impaired imprinting due to contaminants adhered to the mold.

The silicon-based compound may include a silicone polymer and a silicone resin.

The silicone polymer is a polyorgano siloxane based on a weight average molecular weight of 10,000 to 100,000 or less, preferably 10,500 to 99,500, and may have a relatively strong adhesive force compared to silicone resin. If the weight average molecular weight of the silicone polymer is 10,000 or less, the elastic restoring force may be insufficient, and thus the adhesive strength with the substrate 10 may be reduced.

The polyorganosiloxane includes methyl group, ethyl group, propyl group, butyl group, phenyl group, vinyl group, allyl group, (meth) acrylic group, hydroxy group, cyclohexyl group and the like.

In detail, the silicone polymer may be polydimethylsiloxane, polydimethylmethylphenylsiloxane, polymethylphenylsiloxane, polyoxydimethylsiloxane, poly The compound may include any one or more compounds selected from polymethylsiloxane, polymethylhydroxysiloxane, and polyphenylhydroxy siloxane.The silicone polymer may improve adhesion of the adhesive layer 32. , The heat resistance characteristics and elastic restoring force of the adhesive layer 32 are improved.

In addition, the silicone resin is a polyorgano siloxane series having a weight average molecular weight of 500 to 10,000, preferably 600 to 9,500, and has a lower molecular weight and flexibility than the silicone polymer, and may have a relatively weak adhesive force. . If the weight average molecular weight of the silicone resin is less than 500, the ability to control the adhesive strength is lowered, and if it exceeds 10,000 there is a problem that it does not mix well with the polymer by the high viscosity.

In detail, the silicone resin may include any one or more compounds selected from polydimethylsiloxane, polyethylsiloxane, polydipropylsiloxane, polymethylethylsiloxane, and polymethylphenylsiloxane, and may be a polyethersilicone, polyestersilicone, or hydroxy group. It may also include a siloxane containing. Silicone resin plays a role of improving the softness property together with the heat resistance property and adjusting the viscosity of the pressure-sensitive adhesive.

The pressure-sensitive adhesive composition may further comprise a known crosslinking agent, a solvent and a platinum catalyst together with the silicone-based compound to be used as the pressure-sensitive adhesive, the crosslinking agent serves to crosslink the silicone polymer and the silicone resin, and mainly uses a silane crosslinking agent. Specifically, dimethoxy silane, ethoxy silane, methyl diacetoxy methoxy silane, methyl acetoxy dimethoxy silane, vinyl diacetoxy methoxy silane, vinyl acetoxy dimethoxy silane, vinyl acetoxy dimeth A methoxysilane, methyl diacetoxy ethoxysilane, methyl acetoxy diethoxysilane, etc. can be used, and it may not be used depending on the grade and use which are bridge | crosslinked.

The solvent may be used a conventional solvent for dissolving the silicon compound, in detail ethyl acetate, toluene, methyl ethyl ketone, methyl isobutyl ketone, acetone, xylene and benzene, the platinum catalyst is a silicone polymer and silicone It serves as a crosslinking resin, platinum chloride, chloroplatinic acid containing alcohol, for example, hexachloroplatinic acid (Hexachloroplatinic acid) and the like can be used.

The silicone compound may include a silicone polymer and a silicone resin in a ratio of 30:70 to 70:30, in detail, in a ratio of 40:60 to 60:40, and more specifically in a ratio of 35:65 to 65:35. Silicone polymer and silicone resin should be formulated at a certain level to have proper adhesive force and stable thermoforming. Compositions with strong adhesive strength tend to increase ductility to form curved surfaces, whereas curved surface cracks occur and compositions with weak adhesive strength increase stiffness so that cracking does not occur but molding does not occur. Here, the ratio may mean a weight ratio.

The adhesive layer 32 is disposed on one surface of the first adhesive layer 32A interposed between the substrate 10 and the support substrate 31 and the support substrate 31 opposite to the first adhesive layer 32A. The second adhesive layer 32B may be positioned, and at least one of the first adhesive layer 32A and the second adhesive layer 32B may include a silicon-based compound.

Although the constituent materials of the first adhesive layer 32A and the second adhesive layer 32B are not limited, the first adhesive layer 32A may include an acrylate compound or a silicone compound, and the second adhesive layer ( It is preferable that 32B) contains a silicone type compound. When the second adhesive layer 32B is composed of an acrylate compound, it is difficult to realize the adhesive force in a required range, and poor foaming may occur due to insufficient heat resistance during thermoforming.

As for the whole thickness of the double-sided adhesive film 30, 50 micrometers-350 micrometers are preferable. Here, the total thickness of the double-sided adhesive film 30 is a thickness including the support base 31 and the adhesive layer 32 formed on each side. The plastic film is pressed by the upper and lower molds during thermoforming, and the double-sided adhesive film 30 buffers the applied heat and the compressive shock and transfers the shock to the hard coating layer 20. When the total thickness of the double-sided adhesive film 30 is less than 50 μm, the impact due to the compression of the upper and lower molds may not be properly absorbed, and cracks may occur in the curved portions of the hard coating layer 20. On the contrary, when the total thickness of the double-sided adhesive film 30 exceeds 350 μm, the heat transfer efficiency from the lower mold to the hard coating layer 20 may be reduced, and thus the curved surface may not be properly formed.

Next, a laminate according to another embodiment of the present invention will be described with reference to FIG. 2. 2, except that the UV coating layer 50 including the black matrix (BM) layer 40 is further formed between the substrate 10 and the double-sided adhesive film 30. It has the same structure as the laminate of. Hereinafter, the black matrix (BM) layer 40 and the UV coating layer 50 including the same will be described in detail.

The black matrix (BM) layer 40 is a layer added when forming letters or patterns, and mainly uses a paste containing carbon black. Silver or gold tone pastes can be used in place of black matrix pastes. Silver or gold tone pastes are more aesthetically pleasing than black matrix pastes. The thickness after drying is preferably 1 μm to 15 μm, preferably 3 μm to 10 μm. If the thickness is less than 1 μm, the black matrix (BM) layer 40 may not be sufficiently formed, and thus an uncoated area may be generated on the surface. If the thickness is greater than 15 μm, the hard coating layer 20 may be cracked during thermoforming. .

The UV coating layer 50 is used to reduce the thickness step due to the black matrix (BM) layer 40 application. It is best to coat the UV coating layer 50 only between the black matrix (BM) layer 40, but the perfect filling between the black matrix (BM) layer 40 with the UV coating layer 50 provides a very high process accuracy. Require. In order to avoid this difficulty, a method of forming the entire surface including the black matrix (BM) layer 40 as the UV coating layer 50 is used. When the UV coating liquid is applied on the entire surface, the UV coating liquid applied to the black matrix (BM) layer 40 flows down, but the step difference caused by the black matrix (BM) layer 40 can be reduced, thereby adhering the double-sided adhesive film 30. Increases adhesion and eases bubble removal. The UV coating liquid may be used commercially available UV coating liquid without limitation, and in detail, one of the CORI series or NIP series of Chemoptix company can be used.

The UV coating layer 50 should be formed so that the step between the black matrix (BM) layer 40 is 3㎛ or less. When the thickness exceeds 3 μm, a space where the double-sided adhesive film 30 is not adhered to may occur, which causes a decrease in adhesion and bubble generation.

Next, a process of processing the laminate shown in FIGS. 1 and 2 into a three-dimensional shape will be described.

According to an embodiment of the present invention, thermoforming may be performed by placing a laminate in a mold having a suitable shape according to a desired three-dimensional shape, and heating the mold to a temperature at which thermosetting is possible. More specifically, thermoforming may be performed by placing the laminate between upper and lower molds, heating the mold to a predetermined temperature range, and then contacting the heated upper and lower molds to the laminate.

Thermoforming can be accomplished, for example, by heating to a temperature of 90 ° C to 250 ° C, or 100 ° C to 150 ° C. If the thermoforming is performed at a temperature lower than the temperature range, the restoring force of the substrate 10 may be strong, so that a three-dimensional shape of a desired shape may not be obtained, and when the temperature is outside the temperature range, the substrate 10 and the support substrate 31 may be removed. ), The overall laminate properties may be degraded. Thermoforming may be achieved by reaching within the above-described temperature range and holding for a predetermined time, for example, 5 seconds to 300 seconds, or 10 seconds to 100 seconds, but the holding time is not limited thereto, and the substrate 10 ) And the type, thickness of the support base 31, the thickness of the hard coating layer 20, the molding state, and the pressure applied from the mold.

The mold is used for forming the upper mold and the lower mold to be bent to the curvature surface of the display device. At this time, the curvature of the mold, that is, the curvature of the curvature of the mold formed to correspond to the curvature of the display device is preferably to be formed somewhat higher than the curvature of the curvature of the display device. This is because the finished laminate has an elastic spring back phenomenon due to the characteristics of the material, and in view of this, the curvature of the curvature of the mold should be formed somewhat higher than the curvature of the curvature of the actual display device. The elastic spring back phenomenon of the offset and the laminate can be stably attached to the curvature surface of the display device. For example, it is preferable that the curvature degree of the curvature face of the metal mold | die corresponding to the curvature face of a display apparatus is 0.5 degree-15 degree larger than the curvature degree of the curvature surface of an actual display apparatus. Alternatively, after the laminate is placed in one of the upper and lower parts, thermoforming can be performed by applying vacuum and air pressure to close the mold. At this time, a constant pressure may be applied to the laminate, for example, about 1 MPa to about 10 MPa, or about 2 MPa to about 3 MPa for more efficient thermoforming.

Optionally, it is also possible to add a separate process of cutting out unnecessary parts after stereoforming. Accordingly, a plurality of through holes or cutouts may be cut and formed so that a portion corresponding to a shape of a display apparatus to be attached and a function button are exposed.

The laminate of the present invention may have good impact resistance to replace glass. For example, in the laminate of the present invention, cracks may not occur when 22 g of iron balls are freely dropped at a height of 40 cm. In addition, the laminate of the present invention can be stably attached to the curvature surface of the display device because it is easy to implement a three-dimensional shape excellent in conformity.

In addition, the laminate of the present invention can be utilized in various fields. It can be used not only for display devices of mobile devices such as smartphones and tablet PCs, but also for the use of three-dimensional cover substrates or element substrates of various displays such as windows, back covers, vehicle materials, and home appliances.

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

Production Example 1 Preparation of Acrylic Pressure-sensitive Adhesive Composition

83 parts by weight of n-butyl acrylate (BA), 15 parts by weight of methyl acrylate (MA), hydroxyethyl methacrylate (2- HEMA) 2.0 parts by weight of a monomer mixture was added, then 100 parts by weight of ethyl acetate (EA) was added as a solvent. Then, after purging nitrogen gas for 1 hour to remove oxygen, it was maintained at 60 ℃. 0.03 parts by weight of azobisisobutyronitrile (AIBN) was added to the mixture, followed by stirring for 1 hour.

Preparation Example 2 Preparation of Silicone Pressure Sensitive Composition

A silicone polymer is prepared by mixing 50 parts by weight of poly (dimethylsiloxane) and hydroxy terminated having a weight average molecular weight of 20,000 with 100 parts by weight of toluene. 50 parts by weight of polymethylphenylsiloxane having a weight average molecular weight of 2,500 with silicone resin was mixed with 100 parts by weight of toluene, followed by mixing for 1 hour after mixing with the prepared silicone polymer. Hexachloroplatinic acid solution 1.5 parts by weight were mixed and stirred for 2 hours to prepare a silicone pressure-sensitive adhesive composition.

Example 1 Preparation of Laminate According to the Present Invention

50 g of ladder silsesquioxane (SSQ), 49 g of methyl ethyl ketone, and Irgacure photoinitiator 1 g of 250 was mixed to prepare a coating composition. The coating composition was applied to a polycarbonate substrate having a thickness of 500 μm using a slit coater at a thickness of 30 μm, and then dried by heating at a temperature of 95 ° C. for 30 minutes. Next, a specimen was prepared by curing 500 mJ ultraviolet rays under a mercury lamp to cure the coating composition.

In order to form a double-sided adhesive film, the acrylic pressure-sensitive adhesive composition of Preparation Example 1 was applied to one surface of a support substrate 31 having a thickness of 50 μm composed of polyethylene terephthalate (PET), and then dried at 70 ° C. for 10 minutes. After the first adhesive layer 32A was formed to a thickness of 50 μm, a release protective film was attached to protect the first adhesive layer. Thereafter, the silicone adhesive composition of Preparation Example 2 was coated on the other surface (hereinafter, the other surface) of the support base 31 in the same manner, and a second adhesive layer 32B was formed by drying. A double-sided pressure-sensitive adhesive film 30 was prepared. The double-sided adhesive film cured the pressure-sensitive adhesive layer at 90 ℃ 30 minutes to complete the double-sided adhesive film according to the present invention. The completed double-sided adhesive film is attached to the prepared silsesquioxane specimen to prepare a laminate.

Example 2 Preparation of Laminate According to the Present Invention

In the double-sided pressure-sensitive adhesive film, the silicone pressure-sensitive adhesive composition of Preparation Example 2 is applied on one surface of the support base 31 to form a first adhesive layer 32A, and on the other side of the support base 31, A laminated body was manufactured in the same manner as in Example 1 except that the second adhesive layer 32B was formed by applying the acrylic pressure-sensitive adhesive composition.

Example 3 Preparation of Laminate According to the Present Invention

In the double-sided pressure-sensitive adhesive film, the silicone pressure-sensitive adhesive composition of Preparation Example 2 is coated on one surface of the support base material 31 to form a first adhesive layer 32A, and on the other side of the support base material 31, A laminate was prepared in the same manner as in Example 1, except that the second adhesive layer 32B was formed by applying the silicone pressure-sensitive adhesive composition.

Comparative Example 1 Production of Laminate

In the double-sided pressure-sensitive adhesive film, the acrylic pressure-sensitive adhesive composition of Preparation Example 1 was applied on one surface of the support base 31 to form a first adhesive layer 32A, and on the other side of the support base 31, A laminate was prepared in the same manner as in Example 1, except that the second pressure-sensitive adhesive layer 32B was formed by applying the acrylic pressure-sensitive adhesive composition.

Double-sided adhesive film structure and characteristics		Example 1	Example 2	Example 3	Comparative Example 1
Adhesive force (gf / inch)	First adhesive layer	1,000	500	500	1,000
	2nd adhesion layer	150	1,000	150	1,000
PC substrate and adhesive force (after curving)		River	medium	medium	River
3D molding defect or bubble phenomenon		none	none	none	transform
Curved Forming		O	O	O	O

Table 1 is a result of analyzing the adhesive properties and molding properties of the laminate of Examples 1 to 3 and Comparative Example 1. As can be seen in Table 1, the adhesive force with the PC substrate was confirmed that the acrylic adhesive layer is 1,000gf / inch, the silicone adhesive layer is 150 ~ 500gf / inch level. On the other hand, in the case of Comparative Example 1, the deformation of the adhesive layer and the bubble generation phenomenon occurred during the 3D curved molding process, while in Examples 1 to 3, it was confirmed that the deformation and bubble generation of the adhesive layer did not occur at all. .

Example 4 Preparation of Laminate According to the Present Invention

50 g of ladder silsesquioxane (SSQ), 49 g of methyl ethyl ketone, and 1 g of photoinitiator Irgacure 250 were mixed to prepare a coating composition. The coating composition was applied to a polycarbonate substrate having a thickness of 500 μm using a slit coater at a thickness of 30 μm, and then dried by heating at a temperature of 95 ° C. for 30 minutes. Next, a specimen was prepared by curing 500 mJ ultraviolet rays under a mercury lamp to cure the coating composition.

A silicone pressure-sensitive adhesive composition and an acrylate compound comprising polydimethylsiloxane as a silicone polymer, polymethylphenylsiloxane as a silicone resin, dimethoxysilane as a crosslinking agent, toluene as a solvent, and platinum chloride as a platinum catalyst. The pressure-sensitive adhesive composition including the acrylic pressure-sensitive adhesive composition was applied to both sides of a 30-μm-thick polyethylene terephthalate (PET) support base 31 to make a double-sided pressure-sensitive adhesive film having a total thickness of 50 μm, and attached to the back of the fabricated specimen. .

The specimen was placed between upper and lower molds to bend to have a curved surface having a radius of curvature of 15 mm, and left at 150 ° C. for 20 seconds, and then the upper and lower molds were joined at a pressure of 2 MPa. After standing for 15 seconds in a state where the bonding is completed, the molded specimen was collected by separating the upper and lower molds to obtain a laminate. Table 2 shows the cracks and the like of the obtained laminate. O when cracks occurred, and X did not occur.

[Examples 5 to 7] Preparation of Laminates According to the Present Invention

Example 4, except that the pressure-sensitive adhesive composition was applied to both surfaces of the polyethylene terephthalate (PET) support substrate 31 having a thickness of 50 μm, thereby manufacturing a double-sided adhesive film having a total thickness of 150 μm, 250 μm, and 350 μm, respectively. In the same manner as in the laminate was prepared. Table 2 shows the cracks and the like of the laminate in the same manner as in Example 4.

Example 8 Preparation of Laminate According to the Present Invention

A laminate was prepared in the same manner as in Example 4, except that a pressure-sensitive adhesive composition was applied on both sides of a 30-μm-thick polyethylene terephthalate (PET) support substrate 31 to produce a double-sided adhesive film having a total thickness of 40 μm. Prepared. Table 2 shows the cracks and the like of the laminate in the same manner as in Example 4.

[Examples 9 to 10] Production of Laminates According to the Present Invention

The same method as in Example 4, except that the pressure-sensitive adhesive composition was applied to both sides of the support substrate 31 of polyethylene terephthalate (PET) having a thickness of 50 μm, thereby producing a double-sided adhesive film having a total thickness of 400 μm and 500 μm, respectively. It manufactured by the said and obtained laminated body. The crack generation or the like of the obtained laminate was analyzed in the same manner as in Example 4, and is shown in Table 2.

	Example 4	Example 5	Example 6	Example 7	Example 8	Example 9	Example 10
Hard Coating Thickness (㎛)	30	30	30	30	30	30	30
PC substrate thickness (㎛)	500	500	500	500	500	500	500
Double-sided Adhesive Film Overall Thickness (㎛)	50	150	250	350	40	400	500
Curved Forming	O	O	O	O	O	O	X
Curved surface cracks	X	X	X	X	O	O	O

As can be seen from Table 2, when the total thickness of the double-sided pressure-sensitive adhesive film 30 of the laminate is 50㎛ to 350㎛ (Examples 4 to 7), there is no cracking of the curved portion while having a constant radius of curvature Was observed. However, when the total thickness of a double-sided adhesive film was less than 50 micrometers (Example 8), it was observed that a crack generate | occur | produces in a curved part. Moreover, when the total thickness of the double-sided adhesive film exceeded 350 micrometers (Examples 9-10), the crack generate | occur | produced also in the curved part. Furthermore, Example 10 whose total thickness of a double-sided adhesive film was 500 micrometers could not form the curved part as much as desired.

Example 11 Preparation of Laminate According to the Present Invention

50 g of ladder silsesquioxane (SSQ), 49 g of methyl ethyl ketone, and 1 g of photoinitiator Irgacure 250 were mixed to prepare a coating composition. The coating composition was applied to a polycarbonate substrate having a thickness of 500 μm using a slit coater at a thickness of 30 μm, and then dried by heating at a temperature of 95 ° C. for 30 minutes. Next, a specimen was prepared by curing 500 mJ ultraviolet rays under a mercury lamp to cure the coating composition.

A silicone polymer comprising polydimethylsiloxane, silicone resin, and polymethylphenylsiloxane in a composition ratio of 30:70, toluene as a solvent, platinum chloride as a platinum catalyst, and an acrylate compound. A pressure-sensitive adhesive composition comprising an acrylic pressure-sensitive adhesive composition was applied to both sides of a support substrate 31 of polyethylene terephthalate (PET) having a thickness of 30 μm, respectively, to form a double-sided pressure-sensitive adhesive film having a total thickness of 50 μm, and to the back of the fabricated specimen. Attached.

The specimen was placed between upper and lower molds to bend to have a curved surface having a radius of curvature of 15 mm, and left at 150 ° C. for 20 seconds, and then the upper and lower molds were joined at a pressure of 2 MPa. After standing for 15 seconds in a state where the bonding is completed, the molded specimen was collected by separating the upper and lower molds to obtain a laminate. Table 3 shows the cracks and the like of the obtained laminate. O when cracks occurred, and X did not occur.

Examples 12 to 18 Preparation of Laminates According to the Present Invention

A laminate was obtained in the same manner as in Example 11, except that the silicone polymer and the silicone resin were blended in the same manner as the composition ratios shown in Table 3 below. The crack occurrence or the like of the obtained laminate was analyzed in the same manner as in Example 11, and is shown in Table 3 below.

Double sided adhesive film composition	Example 11	Example 12	Example 13	Example 14	Example 15	Example 16	Example 17
Silicone polymer	30	50	70	0	20	80	100
Silicone resin	70	50	30	100	80	20	0
Adhesion level	medium	medium	medium	about	about	River	River
Curved Forming	O	O	O	X	X	O	O
Curved surface cracks	X	X	X	X	X	O	O

As can be seen from Table 3, when the silicone polymer and the silicone resin were included in the ratio of 30:70 to 70:30 (Examples 11 to 13), it was observed that the curved portion was formed uniformly without cracking the curved portion. .]

10: description

20: hard coating layer

30: double sided adhesive film

31: support substrate

32A: first adhesive layer

32B: second adhesive layer

40: black mattress (BM) layer

50: UV coating layer

Claims (12)

1. Base material 10;

   A hard coating layer 20 disposed on one surface of the substrate 10;

   It includes a double-sided adhesive film 30 located on the other side of the base 10,

   The double-sided adhesive film 30 includes a support base material 31 and an adhesive layer 32 respectively positioned on both sides of the support base material 31, and at least one of the pressure-sensitive adhesive layer 32 includes a silicon-based compound. Laminate.
2. The method of claim 1,

   The adhesive layer 32 is a laminate comprising any one or more selected from a rubber compound, an acrylic compound, a silicone compound, a urethane compound, and an organic-inorganic hybrid type compound.
3. The method of claim 1,

   The adhesive layer 32 is interposed between the base material 10 and the support base material 31 and positioned on one surface of the base material 10, and the first adhesive layer 32A and the other surface of the support base material 31. A second adhesive layer 32B positioned at

   The second adhesive layer (32B) is a laminate containing a silicon-based compound.
4. The method of claim 1,

   The silicon compound is a laminate comprising a silicone polymer and a silicone resin.
5. The method of claim 4, wherein

   The silicone polymer is a polyorganosiloxane having a weight average molecular weight greater than 10,000 to 100,000 or less,

   The silicone resin is a laminate that is a polyorganosiloxane having a weight average molecular weight of 500 to 10,000.
6. The method of claim 5,

   The silicone polymer comprises at least one compound selected from polydimethylsiloxane, polydimethylmethylphenylsiloxane, polymethylphenylsiloxane, polyoxydimethylsiloxane, polymethylsiloxane, polymethylhydroxysiloxane and polyphenylhydroxysiloxane,

   The silicone resin comprises at least one compound selected from polydimethylsiloxane, polyethylsiloxane, polydipropylsiloxane, polymethylethylsiloxane, polymethylphenylsiloxane, polyethersilicone, polyestersilicon and a siloxane including a hydroxy group. Phosphorus laminate.
7. The method of claim 4, wherein

   The silicon compound is a laminate comprising a silicone polymer and a silicone resin in a weight ratio of 30:70 to 70:30.
8. The method of claim 1,

   The overall thickness of the double-sided pressure-sensitive adhesive film 30 is 50 ㎛ to 350 ㎛ laminate.
9. The method of claim 1,

   The adhesive layer 32 is a laminate further comprising a crosslinking agent and a platinum catalyst.
10. The laminate according to claim 1, further comprising any one or more of a black matrix (BM) layer (40) and a UV coating layer (50) between the substrate (10) and the double-sided adhesive film (30).
11. Silicone type adhesive composition containing a silicone polymer, a silicone resin, a crosslinking agent, a solvent, and a platinum catalyst.
12. The method of claim 11,

    The silicone pressure sensitive adhesive composition is a silicone pressure sensitive adhesive composition comprising a silicone polymer and a silicone resin in a weight ratio of 30:70 to 70:30.

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