KR102701756B1 - Contamination-proof lamination film with anti-fouling and water-repellency - Google Patents

Abstract

The present invention relates to a laminated film comprising: a self-repairing layer comprising a urethane resin; a contamination-preventing coating layer positioned on an upper portion of the self-repairing layer; an elastic substrate layer positioned on a lower portion of the self-repairing layer; and an adhesive layer positioned on a lower portion of the elastic substrate layer, wherein the contamination-preventing coating layer comprises a water-repellent compound having a urethane bond.

Description

{Contamination-proof lamination film with anti-fouling and water-repellent performance}

The present invention relates to a laminated film that can be applied to various adherends such as flat and curved surfaces, and has scratch protection and self-healing performance and a contamination prevention function that is maintained for a long period of time.

Glass, dishes, marble, etc. are easily scratched on the surface by physical external contact. Once scratched, it can cause deformation of the surface and interior, and can also form a state in which it can be easily destroyed by external impact.

In addition, there may be problems that deteriorate the appearance, such as reduced gloss or observation of scratches, and this may have problems that may reduce transparency and visibility, especially in glass or transparent films, so there may be restrictions on its use for optical purposes or windows.

To solve these problems, surface protection films with self-restoring functions are used in cases where visibility must be secured, such as on automobile windshields, display glass, and transparent plastic plates, and scratches or surface damage caused by small stones or dust must be prevented.

The surface protection film has the form of a laminated film in which a plurality of layers are laminated, including a substrate layer forming the basic shape of the film, a self-restoring layer on the surface of the substrate layer, and an adhesive layer on the lower surface of the substrate layer. It is important that each layer performs its function while remaining integral as a single laminated film.

Recently, as it has become necessary to apply the above-mentioned laminated film to curved substrates such as curved displays or automobile windshields, it is also important to have performance that allows attachment not only to flat substrates but also to curved surfaces such as automobile windshields.

Furthermore, the adherend as described above needs to be kept in a clean state at all times by preventing contamination of the surface so that contamination can be easily removed or self-removed. Currently, a method of forming a coating layer by applying a contamination-repellent or water-repellent functional material to the surface of glass, the surface of a film, etc., is generally used as a method of providing dirt-repellent and water-repellent properties.

Since such antifouling and water-repellent functional materials are easily damaged by physical contact on the surface of the adherend and can also be easily damaged by external weather phenomena such as wind and precipitation, they are utilized in a method of re-forming the coating layer by applying it at regular intervals.

Recently, in order to solve these problems, antifouling and water-repellent functional compounds are mixed in the top layer of the surface protection film to form a film layer. However, compared to forming a coating layer by directly applying functional compounds to the surface, there is a problem that the antifouling and water-repellent functions are reduced or the functionality is not maintained for a long period of time.

Korean Patent Publication No. 2019-0025455 relates to a water-repellent coating agent for automobile glass, and discloses a technology for increasing the durability and water-repellent durability of a coating film by adding an acid component to a mixture of a fluorine-containing silane; dimethicone; and cyclopentasiloxane, reacting the mixture, and then diluting the mixture with an additional solvent, and further including 0.1 to 5 parts by weight of disodium metasilicate or sodium silicate as an alkalizing agent.

However, there is no disclosure regarding a laminated film that satisfies both the self-healing function for scratches and the anti-fouling and water-repellent functions while maintaining the anti-fouling and water-repellent functions for a long period of time by being attached in the form of a laminated film.

Korean Patent No. 2381911 relates to an easy-to-install exterior protective film for preventing scratches on a windshield of an automobile, and discloses an exterior protective film for preventing scratches on a windshield of an automobile, which is laminated in the following order: a release film layer, an adhesive layer, a base film layer, a surface coating layer, and a protective film layer.

A protective film is disclosed that can be easily installed on curved surfaces such as automobile windshields without heat treatment, has a self-healing function, and has a surface coating layer with anti-fouling, water-repelling, and scratch-healing functions. However, there is a limitation in that it does not exhibit sufficient anti-fouling and water-repelling functions when a small amount of a water-repellent compound is added.

Meanwhile, Korean Patent No. 1557182 discloses a solar cell protective film and a solar cell including the same, which comprises a barrier film, an adhesive layer, and a fluorine-based polymer layer, wherein the barrier film includes at least one of a substrate layer, an organic-inorganic hybrid layer, and an inorganic blocking layer.

However, there is no disclosure regarding a laminated film that has self-healing function of formed scratches, maintains anti-fouling and water-repellent functions, and can be applied to both flat and curved surfaces.

Accordingly, there is a need to develop an improved functional laminated film that maintains the existing self-healing function and the function of a protective film that prevents scratches from the outside, has the effect of being easy to attach to various adherends, and has anti-fouling and water-repellent functions and can be maintained for a long period of time.

Republic of Korea Publication Patent No. 2019-0025455 (2019.03.11) Republic of Korea Patent No. 2381911 (2022.03.29) Republic of Korea Patent No. 1557182 (2015.09.24)

The present invention relates to a laminated film that can be attached to various adherends, and aims to provide a laminated film that has a contamination prevention function and a water-repellent function on an external surface, and that can be applied and attached to various shapes of surfaces such as curved surfaces or flat surfaces.

The present invention also aims to provide a laminated film that prevents contamination and damage to the surface of an adherend by external contaminants or external physical impacts by attaching the film to the surface of an adherend, and has a self-restoring function when damage such as scratches occurs.

In particular, the present invention aims to provide a laminated film which prevents a coating layer having anti-pollution and water-repellent functions from being peeled off from the laminated film or easily lost due to wear, thereby maintaining anti-pollution and water-repellent functions for a long period of time, and which also maintains its own self-restoring function for a long period of time.

In order to solve the above-mentioned problems, the laminated film according to the present invention has the function of protecting the surface when applied to various surfaces, and relates to a laminated film that is attached to the surface of various adherends such as automobile windshields, glass windows, display glass, optical films, etc., and has no surface distortion, self-restoring properties for scratches, and water-repellent and antifouling effects.

Specifically, a laminated film according to the present invention comprises a self-repairing layer including a urethane resin, a contamination-preventing coating layer positioned on an upper portion of the self-repairing layer, an elastic substrate layer positioned on a lower portion of the self-repairing layer, and an adhesive layer positioned on a lower portion of the elastic substrate layer, wherein the contamination-preventing coating layer comprises a water-repellent compound having a urethane bond.

In the present invention, the water-repellent compound having the urethane bond may have a structure represented by the following chemical formula 1.

<Chemical Formula 1>

Y-[-HNO=CO-[X-(A) _l -(B) _m -X']-OC=ONH-] _n -Y'

The above A and B are the same or different from each other, and are each independently one selected from a fluorinated C ₁ to C ₅ alkoxy group, a siloxane group primary substituted with a C ₁ to C ₃ alkyl, and a siloxane group secondary substituted with a C ₁ to C ₃ alkyl.

The above l and m are each independently integers from 1 to 50,

The sum of the above l and m is 10 to 100,

The above n is an integer from 1 to 10.

The above X and X' are the same or different, and each independently represents one selected from a fluorinated C ₁ to C ₅ alkoxy group, a silane group primary substituted with a C ₁ to C ₃ alkyl, and a silane group secondary substituted with a C ₁ to C ₃ alkyl.

The above Y and Y' are the same or different, and are each independently one selected from a silane group primary substituted with a C ₁ to C ₃ alkyl, a silane group secondary substituted with a C ₁ to C ₃ alkyl, and a silane group tertiarily substituted with a C ₁ to C ₃ alkyl.

More specifically, the A may be -(CF ₂ CF ₂ O)-, and the B may be -(CF ₂ O)-.

In the present invention, the thickness of the anti-contamination coating layer may be 1 to 100 nm (nanometers).

In the present invention, the contamination prevention coating layer may be formed of a water-repellent coating solution containing a water-repellent compound having a urethane bond and a fluorine-based solvent, and having a solid content of 0.05 to 1%.

In the present invention, the self-recovering layer may include a urethane resin manufactured by reacting a prepolymer obtained by mixing 100 parts by weight of a polyester prepolymer, 30 to 55 parts by weight of a polyurethane prepolymer, and 30 to 60 parts by weight of an isocyanate compound.

In the present invention, the adhesive layer includes an acrylic adhesive and/or a silicone adhesive, and the adhesive strength of the adhesive layer can be 50 to 1500 gf/in.

In the present invention, the laminated film may further include at least one selected from the group consisting of an upper surface adhesive protective film layer and a release film layer.

In the present invention, the elastic substrate layer may contain 5 to 50 parts by weight of a polyurethane oligomer, 30 to 70 parts by weight of an acrylic monomer, and 0.5 to 5 parts by weight of a photoinitiator.

The laminated film according to the present invention has the effect of facilitating attachment without hindrance to the formation of an adhesion surface as an adherend having a material such as glass or a plastic film.

In particular, the present invention has excellent antifouling and water-repelling performance while maintaining the existing self-healing function and surface protection function, and has the effect of maintaining the antifouling and water-repelling performance for a long period of time.

The present invention also has the effect of maintaining antifouling and water-repellent functions even when the surface is worn due to external weather changes, physical contact, etc.

Figure 1 is a schematic diagram of a vertical cross-section of a laminated film according to one embodiment of the present invention.
Figure 2 is a schematic diagram of a vertical cross-section of a laminated film according to another embodiment of the present invention.

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 practice it; however, this is only an example, and the scope of the rights of the present invention is not limited by the following contents.

As used herein, "preferred" or "preferably" refers to an embodiment of the invention that has a particular advantage under certain conditions. However, other embodiments may also be preferred under the same or different conditions. Furthermore, the fact that one or more preferred embodiments is not intended to imply that other embodiments are not useful, nor does it exclude other embodiments that are within the scope of the invention.

The term "including" as used herein is used to list materials, compositions, devices, and methods useful in the present invention, but is not limited to the listed examples.

A laminated film according to the present invention comprises a self-repairing layer comprising a urethane resin; a contamination-preventing coating layer positioned on the upper portion of the self-repairing layer, wherein the contamination-preventing coating layer comprises a water-repellent compound having a urethane bond.

The present invention is not limited to a curved adherend such as a car windshield or a flat adherend such as a flat monitor protective film, and is easy to attach, and has excellent properties of wear resistance, self-healing, stain resistance, and water repellency, and in particular, unlike a water repellent applied in the form of a conventional coating agent, it has excellent wear resistance, and has the effect of maintaining the stain resistance and water repellency of the surface contamination prevention coating layer for a long period of time.

Below, each component of the invention is described in more detail.

1. Self-healing layer

This is a layer that has wear resistance by suppressing the formation of scratches due to external physical stimuli, and has the function of self-healing when scratches are formed, removing the scratches and self-restoring to the same state as the original surface.

The above self-recovery layer may include a urethane resin manufactured by reacting a prepolymer obtained by mixing 100 parts by weight of a polyester prepolymer, 30 to 55 parts by weight of a polyurethane prepolymer, and 30 to 60 parts by weight of an isocyanate compound.

By manufacturing with the composition as described above, the adhesive layer, self-repairing layer, and contamination prevention coating layer are sequentially laminated, and thus the film has flexibility, making it easy to attach to various surfaces such as curved or flat surfaces.

If the content of the isocyanate compound is excessive compared to the above content, there is a problem that the hardness increases and the scratch recovery ability and the press mark recovery ability are significantly reduced, and if the content of the isocyanate compound is small compared to the above content, there is a problem that the hardness decreases and the material becomes soft, resulting in reduced elasticity and softening.

Meanwhile, the self-recovery layer is configured to include a urethane resin including a urethane bond, so that it has excellent adhesion to the anti-fouling coating layer positioned thereon, and the coating layer is not easily worn off and can be maintained for a long period of time, thereby having the effect of maintaining anti-fouling and waterproofing performance for a long period of time.

If the content of the above polyurethane prepolymer is excessive, there is a problem that unreacted prepolymer remains even after complete reaction with isocyanate, resulting in stickiness, and if the content is small, there is a problem that self-restoring elasticity is reduced.

Meanwhile, the self-restoring layer may have a thickness of 10 to 60 ㎛ (micrometers) and a Young's modulus (MPa) of 10 to 200 MPa. If it is thicker than the above thickness, the viscoelasticity of the prepolymer and the isocyanate is low, making it difficult to apply it with a uniform thickness of 60 ㎛ or more, and there is a problem that a bending phenomenon occurs in a form with distorted visibility, and if it is thinner than the above thickness, there is a problem that the self-restoring ability is significantly reduced, so it is preferable to have the above thickness range.

In addition, when the Young's modulus is smaller than the above value, there is a problem that the hardness is excessively reduced and the elasticity is reduced and the material becomes soft, and when the Young's modulus is larger than the above value, there is a problem that the hardness increases and the self-restoring ability is significantly reduced. Therefore, it is desirable that the Young's modulus of the self-restoring layer be satisfied within the above range in order to maintain high elasticity while having a self-healing function.

The above self-restoring layer may further include additives that absorb, block, or preserve external electromagnetic waves, such as ultraviolet absorbers, infrared absorbers, and ultraviolet stabilizers, in order to block ultraviolet rays from entering the interior of the car.

The above self-restoring layer can be manufactured through the following process.

That is, the self-healing coating resin of the self-healing layer is a composition in which 20 to 60 parts by weight of polyurethane prepolymer is mixed with 100 parts by weight of polyester prepolymer and a dihydroxyl polyurethane prepolymer, and a crosslinking agent is at least one isocyanate selected from the group consisting of hexamethylene diisocyanate (HDI), methylenebis(4-cyclohexylisocyanate), H12MDI, polymeric isocyanates, or poly(diisocyanate), HDI, isocyanurate of IDPI, and poly(MDI), and a coating composition for forming a self-healing layer is prepared by using a micro gravure coater. The coating layer can be manufactured by forming a coating composition having a viscosity of 10 to 500 cP using a coating composition, drying, curing at a temperature of 60 to 150°C for 1 to 3 minutes, and maturing at a temperature of 20 to 50°C for 40 to 170 hours.

2. Anti-pollution coating layer

The anti-pollution coating layer is a layer that comes into contact with the external environment in a laminated film that is coated on top of the self-recovery layer and is attached to an adherend. It is a surface that may come into contact with wind, precipitation, and external objects.

General water-repellent coating agents use compounds that react with reactive groups such as hydroxyl groups on the surface of the adherend, and are fixed to the surface of the adherend by reacting with the hydroxyl groups on the surface of the adherend in the applied state. In this state, they come into contact with the external environment, but the hydroxyl groups ( ^-OH ) that are exposed on the surface of the adherend and not chemically bonded have a molecular structure like water, so they easily react with moisture and are not functional groups that have a high bonding force with the adherend, so there is a problem that they are easily washed away by rain or moisture in the air, are easily damaged by external physical stimuli, and can easily fall off from the adherend when damaged.

The anti-pollution coating layer of the present invention is applied with a very thin thickness on the surface of the self-repairing layer, so that it has its own anti-pollution and water-repellent functions, and also has excellent adhesion and bonding strength with the self-repairing layer, so that it is not easily removed and can be maintained even under external physical stimuli.

That is, since it is applied in a very thin thickness, when a scratch is formed due to an external stimulus, the damage to the layer is healed by the self-healing function of the self-recovery layer, and the anti-fouling coating layer formed on the surface maintains anti-fouling and water-repellent performance due to its high bonding strength with the self-recovery layer.

Specifically, the antifouling coating layer includes a water-repellent compound having a urethane bond, which is capable of interacting with the urethane bond included in the urethane resin included in the self-repairing layer described above, so that it is maintained as one layer with the self-repairing layer, so that the self-healing function of the self-repairing layer is maintained as it is, while preventing the antifouling coating layer from peeling off, thereby having the effect of maintaining the antifouling and water-repelling functionality for a long period of time.

More specifically, the water-repellent compound having the urethane bond may have a structure represented by the following chemical formula 1.

<Chemical Formula 1>

Y-[-HNO=CO-[X-(A) _l -(B) _m -X']-OC=ONH-] _n -Y'

The above A and B are the same or different from each other, and can each independently be any one selected from a fluorinated C ₁ to C ₅ alkoxy group, a siloxane group primary substituted with a C ₁ to C ₃ alkyl, and a siloxane group secondary substituted with a C ₁ to C ₃ alkyl.

The above l and m are each independently integers from 1 to 50,

The sum of the above l and m is 10 to 100,

The above n is an integer from 1 to 10.

The above X and X' are the same or different, and each independently represents one selected from a fluorinated C ₁ to C ₅ alkoxy group, a silane group primary substituted with a C ₁ to C ₃ alkyl, and a silane group secondary substituted with a C ₁ to C ₃ alkyl.

The above Y and Y' are the same or different, and can each independently be any one selected from a silane group primary substituted with a C ₁ to C ₃ alkyl, a silane group secondary substituted with a C ₁ to C ₃ alkyl, and a silane group tertiarily substituted with a C ₁ to C ₃ alkyl.

The above A and B are moieties that impart antifouling and water-repellent properties, and may each independently be any one selected from a fluorinated C ₁ to C ₅ alkoxy group, a siloxane group primary substituted with a C ₁ to C ₃ alkyl, and a siloxane group secondary substituted with a C ₁ to C ₃ alkyl.

It is configured to include a repeating unit containing a fluorinated alkoxy group or an alkyl-substituted silane group, and serves to provide an antifouling and water-repellent performance to the antifouling coating layer.

More preferably, A and B may be composed of fluorinated C ₁ to C ₅ alkoxy groups, and most preferably, A may be a fluorinated C ₂ alkoxy group (-(CF ₂ CF ₂ O)-), and B may be a C ₁ alkoxy group (-(CF ₂ O)-).

The above A and B can also be combined randomly without having to be combined in a specific order.

The above l and m can each independently be integers from 1 to 50, and their sum (l+m) can be from 10 to 100, but this is to indicate the ratio of the water-repellent part and the urethane bond within the above range.

When the value of l+m is less than the above range, there is a problem that the antifouling and water-repellent performance becomes minimal, and when the value is greater than the above range, the structure exhibiting antifouling and water-repellent performance per urethane bond becomes large, and there is a problem that the adhesion and bonding strength with the self-recovering layer decrease.

The term 'fluorinated' or 'alkyl substituted' compounds as described above includes, except where otherwise noted, compounds substituted with one fluorine or one alkyl, compounds substituted with two or more fluorines or two or more alkyls, or compounds in which all possible substituents are replaced with fluorines or alkyls.

The thickness of the above anti-contamination coating layer may be 1 to 100 nm (nanometers). More preferably, it may be 2 to 30 nm.

If it is thicker than the above thickness, there is a problem that the slipperiness is drastically reduced, resulting in poor water-proofing and water-repellent properties, and if it is thinner than the above thickness, there is a problem that the slipperiness, water-repellent properties, contamination resistance, and durability are all reduced. Therefore, it is desirable to form it with a thickness within the above range so that it can exhibit both excellent self-restoring performance and water-proofing and water-repellent properties.

The above-mentioned anti-contamination coating layer may be formed of a water-repellent coating solution containing a water-repellent compound having a urethane bond and a fluorine-based solvent, and having a solid content of 0.05 to 1%. More preferably, the solid content may be 0.08 to 0.3%.

If the solid content is lower than the above range, there is a problem that the wear resistance of the antifouling coating layer is reduced and the coating layer is easily peeled off, and if the solid content is higher than the above range, there is a problem that the antifouling and water-repellent performance is reduced.

It is preferable that the above-mentioned anti-contamination coating layer be transparent in appearance, have a viscosity of 1 to 10 cP, and have a specific gravity of 1.5 to 2.0.

By being formed into a transparent layer, visibility can be secured when used as a film for protecting car windshields or displays.

3. Elastic substrate layer

Preferably, when the laminated film includes an elastic substrate layer, it can be formed to be positioned below the self-restoring layer or above the adhesive layer, and when the laminated film includes an upper adhesive protective film layer, it can be added to be positioned at the upper outer surface of the laminated film, that is, the upper end of the outermost surface exposed to the outside.

The above elastic substrate layer is a layer that improves the elasticity of the laminated film, and can have the characteristic of being easy to construct even on a curved surface.

The above elastic substrate layer may contain 5 to 50 parts by weight of a polyurethane oligomer, 30 to 70 parts by weight of an acrylic monomer, and 0.5 to 5 parts by weight of a photoinitiator. However, the term "containing" herein may be understood to mean a coating layer formed using the same.

The above elastic substrate layer may have a thickness of 50 to 500 ㎛, a tensile strength of 10 to 50 MPa, an elongation of 50 to 500%, and a Young's modulus (MPa) of 50 to 700 MPa.

4. Adhesive layer

The adhesive layer is a layer for attachment to the surface of an adherend. For easy attachment, the adhesive layer can be stored with a release film attached, and then constructed by removing the release film and attaching the adhesive layer so that it touches the surface of the adherend.

The adhesive layer includes an acrylic adhesive and/or a silicone adhesive, and the adhesive strength of the adhesive layer can be 50 to 1500 gf/in.

The above acrylic adhesive can be configured so that adhesive transfer or contamination of the adherend does not occur by using an adhesive having a high molecular weight of 300,000 to 700,000 and a weight average molecular weight (Mw).

Specifically, the acrylic adhesive may be an acrylic copolymer solution-polymerized with 2-hexyl ethyl acrylate, butylacrylate, vinyl acetate, and 2-hydroxyethyl methacrylate acrylic acid, and the adhesive strength of the acrylic adhesive is preferably in the range of 50 to 1500 gf/in, and preferably 200 to 1000 gf/in.

If the adhesive strength of the acrylic adhesive is lower than the above range, the adhesive strength is weak and the adherend is easily separated after attachment, or the adhesive layer and the adhered layer in the laminated film, such as a self-restoring layer or an elastic substrate layer, are easily separated. If the adhesive strength exceeds the above range, the adhesive strength is strong and it is difficult to remove the laminated film from the adherend, which causes a problem in that replacement is difficult.

The above adhesive layer may have a thickness of 3 to 30 ㎛ (micrometers). If it is thicker than the above thickness, there may be a problem of reduced visibility due to a fine orange peel, which is a distortion phenomenon of the adhesive layer itself, and a problem of the adhesive becoming sticky on the cut surface during construction. If it is thinner than the above thickness, the adhesive strength is reduced, making it difficult to construct the film during attachment, and the edge may lift after attachment. In addition, since the adhesive layer is too thin to sufficiently adhere to the adherend, there may be a problem of bubbles being generated.

5. Laminated film

The present invention relates to a laminated film for protecting the surface of an adherend by attaching it to an adherend of various materials. The laminated film is easy to attach to a flat or curved surface, and is attached to the surface of ceramics such as glass, or various plastic materials such as polycarbonate and polyethylene, and has antifouling and water-repellent functions as well as self-healing properties for scratches.

Specifically, the self-repairing layer comprises a urethane resin; a contamination-preventing coating layer positioned on the upper portion of the self-repairing layer, an elastic substrate layer positioned on the lower portion of the self-repairing layer, and an adhesive layer positioned on the lower portion thereof, wherein the contamination-preventing coating layer comprises a water-repellent compound having a urethane bond, and is configured as a multifunctional film that is easy to attach to an adherend, has a self-healing function, and has both an antifouling and water-repelling function.

The above laminated film may further include additional layers as needed in addition to the basic composition layers of an adhesive layer, an elastic substrate layer, a self-recovery layer, and a contamination-preventing coating layer. For example, various functional layers such as a primer layer, an ultraviolet-blocking layer, an infrared-blocking layer, and a color layer may be further added. In the case of further including such additional layers, they may be included in any position of the layers constituting the basic laminated film.

Specifically, the composition of each layer may include anything necessary to secure additional functionality, for example, in the case of the infrared blocking layer, it may include an infrared absorbent such as ATO (Antimon Tin Oxide), CTO (Cesium doped tungsten oxide), ITO (Indium Tin Oxide), etc., and in the case of the color layer, it may include a dye capable of expressing color.

FIG. 1 is a schematic diagram of a vertical cross-section of a laminated film according to one embodiment of the present invention, which may be configured as a laminated film having a structure in which an adhesive layer (40), an elastic substrate layer (30), a self-recovering layer (10), and a contamination prevention coating layer (20) are sequentially laminated in the height direction from an adherend.

In the above drawing 1, when additional layers are provided, additional layers can be provided on any surface of any layer.

Specifically, the laminated film may further include at least one selected from the group consisting of a top-surface adhesive protective film layer and a release film layer.

FIG. 2 is a schematic diagram of a vertical cross-section of a laminated film according to another embodiment of the present invention. Referring to FIG. 2, a laminated film having a structure in which a release film layer (50), an adhesive layer (40), an elastic substrate layer (30), a self-recovering layer (10), an anti-contamination coating layer (20), and an upper adhesive protective film layer (60) are sequentially laminated in the height direction from the bottom surface is illustrated.

In the case where the lower part of the laminated film, i.e., the adhesive layer is configured as the lowermost layer, a release film layer (50) may be further provided below it, and in the case where the upper part of the laminated film, i.e., the anti-contamination coating layer is configured as the uppermost layer, an upper adhesive protective film layer (60) may be provided above it.

In addition, when the release film layer is further included, it may be added so as to be positioned below the adhesive layer. The release film layer is configured to protect the adhesive layer during the process of manufacturing and distributing the laminated film as a finished product. Before attaching to the adherend, the release film layer is removed, and then the adhesive layer is attached to the surface of the adherend.

Meanwhile, the upper surface adhesive protective film layer is attached to protect the contamination prevention film layer located at the top of the laminated film, and to maintain quality by preventing damage to the surface of the laminated film due to external physical stimulation or contact in the finished product state, and to prevent damage to the surface of the laminated film during the process of attaching the laminated film to the adherend.

It is preferable to use a material that does not cause adhesion to the layer with which it comes into contact and does not cause surface damage when removed for the above-mentioned release film layer and the upper adhesive protective film layer, and the material is not particularly limited, and any material that satisfies the relevant properties and intended use may be used.

Hereinafter, the contents of the present invention will be described in more detail based on examples.

Manufacturing example

A laminated film was manufactured in which a release film, an adhesive layer, an elastic substrate layer, a self-recovering layer, and an anti-contamination coating layer were sequentially laminated.

Before forming the self-recovery layer and the anti-contamination coating layer, 1) an elastic substrate layer was manufactured using the method specified below, a release film on one side of the manufactured elastic substrate layer was removed, and then 2) an adhesive layer was formed on the removed side.

1) Manufacturing of elastic substrate layer

A coating solution prepared by mixing 35 parts by weight of polyurethane oligomer, 60 parts by weight of acrylic monomer, and 5 parts by weight of a photoinitiator was applied onto a first release film, a second release film was laminated thereon, and then photocured with a light amount of 500 mJ/cm ² at a wavelength of 200 to 400 nm to prepare an elastic substrate layer with a thickness of 150 um (micrometer).

2) Adhesive layer manufacturing

100 parts by weight of an acrylic copolymer solution-polymerized with 2-hexyl ethyl acrylate, butyl acrylate, vinyl acetate, and 2-hydroxyethyl methacrylate acrylic acid, and 1 part by weight of a metal alkylate curing agent were mixed to prepare a coating solution, and this coating solution was applied to the surface from which the second release film on one side of the elastic substrate layer prepared in 1) was removed, and then after heat curing, it was laminated with a separate release film to prepare an adhesive layer having a thickness of 15 μm.

3) Manufacturing self-healing layer and anti-contamination coating layer

A semi-finished product having an adhesive layer formed on one side of an elastic substrate layer is prepared. After removing the release film attached to the elastic substrate layer on the opposite side of the adhesive layer of the prepared semi-finished product, a self-repairing layer is formed on the removed side, and then a contamination prevention coating layer is manufactured on top of the self-repairing layer.

Finally, to protect the anti-contamination coating layer, an adhesive protective film was attached on top of the anti-contamination coating layer to manufacture a laminated film.

<Manufacture of Examples 1 to 6>

First, a self-recovery layer was prepared by mixing 100 parts by weight of polyester prepolymer, 35 parts by weight of polyurethane prepolymer, and 40 parts by weight of isocyanate compound, and applying a coating solution, followed by heat curing to prepare a 20 μm thickness.

A contamination-preventing coating layer containing a water-repellent compound having the following structure of <Chemical Formula 2> was manufactured.

<Chemical formula 2>

(CH ₃ O) ₃ Si-CH ₂ -CH ₂ -CH ₂ -[-HNO=CO-[CH ₂ CF ₂ O-(-(CF ₂ CF ₂ O)-) _l -(-(CF ₂ O) -) _m -CF ₂ CH ₂ ]-OC=ONH-] _n -CH ₂ -CH ₂ -CH ₂ -CH ₂ -Si(OCH ₃ ) ₃

In the above chemical formula 2, l, m, and n are the same as in chemical formula 1.

<Example 1> 2.9 nm, <Example 2> 5.8 nm, <Example 3> 10.3 nm, <Example 4> 17.5 nm, <Example 5> 23.3 nm, and <Example 6> 30.4 nm. Products of Examples 1 to 6 were manufactured respectively, and then an adhesive protective film was laminated on the upper surface of the contamination prevention coating layer to manufacture a finished product.

<Example 7>

In the above Example 1, instead of forming the anti-fouling coating layer with a thickness of 2.9 nm using the compound of the above <Chemical Formula 2>, a anti-fouling coating layer including a water-repellent compound having the following <Chemical Formula 3> structure was prepared with a thickness of 5.8 nm, in the same manner as in the above Example 1.

<Chemical Formula 3>

(OCH ₃ ) ₃ Si-CH ₂ -CH ₂ -CH ₂ -[-HNO=CO-[(CH ₃ ) ₂ Si-(-(CH ₃ )(CH ₃ CH ₂ )SiO)-) _l -(( CH ₃ ) ₂ SiO)-) _m -(CH ₃ ) ₂ Si]-OC=ONH-] _n -CH ₂ -CH ₂ -CH ₂ -CH ₂ -Si(OCH ₃ ) ₃

In the above chemical formula 3, l, m, and n are the same as in chemical formula 1.

<Comparative Examples 1 to 3>

In the above Example 1, instead of forming the thickness of the contamination prevention coating layer to a thickness of 2.9 nm, products were manufactured with a thickness of <Comparative Example 1> 1.5 nm, <Comparative Example 2> 38.2 nm, and <Comparative Example 3> 51.3 nm, respectively, in the same manner as in the above Example 1.

<Comparative Example 4>

In the above Example 1, instead of the water-repellent compound of <Chemical Formula 2> included in the contamination-preventing coating layer, in the above <Chemical Formula 1>, A is a fluorinated C ₂ alkoxy group (-(CF ₂ CF ₂ O)-) and B is a fluorinated C ₁ alkoxy group (-(CF ₂ O)-) or a fluorine compound that does not include a urethane bond, and the coating was manufactured to a thickness of 5.8 nm, the same method as in the above Example 1 was used.

<Comparative Example 5>

In the above Example 1, instead of the water-repellent compound of <Chemical Formula 2> included in the contamination-preventing coating layer, a silicone compound having a molecular formula in which A in the above <Chemical Formula 1> is a siloxane group primarily substituted with an alkyl of C ₁ and B is a siloxane group secondarily substituted with an alkyl of C ₁ but does not contain a urethane functional group was applied to produce a thickness of 5.8 nm, and the same method as in the above Example 1 was used, except that the coating was produced in the same manner.

[Manufacture of Comparative Examples 6 to 9]

In the above Example 2, instead of manufacturing the self-recovery layer of Example 2, <Comparative Examples 6> to <Comparative Examples 9> were manufactured in the same manner as in the above Example 2, except that the self-recovery layer was manufactured with the following coating liquid composition.

<Comparative Example 6>

In the above Example 2, instead of the self-recovery layer of Example 2, a coating solution prepared by mixing 100 parts by weight of polyester prepolymer, 20 parts by weight of polyurethane prepolymer, and 40 parts by weight of isocyanate compound was applied, and a self-recovery layer prepared to a thickness of 20 μm was included after heat curing, in the same manner as Example 2.

<Comparative Example 7>

In the above Example 2, instead of the self-recovery layer of Example 2, a coating solution prepared by mixing 100 parts by weight of polyester prepolymer, 60 parts by weight of polyurethane prepolymer, and 40 parts by weight of isocyanate compound was applied, and a self-recovery layer prepared to a thickness of 20 μm was included after heat curing, in the same manner as Example 2, except that the coating solution was applied.

<Comparative Example 8>

In the above Example 2, instead of the self-recovery layer of Example 2, a coating solution prepared by mixing 100 parts by weight of a polyester prepolymer, 35 parts by weight of a polyurethane prepolymer, and 20 parts by weight of an isocyanate compound was applied, and a self-recovery layer prepared to a thickness of 20 μm was included after heat curing, in the same manner as Example 2.

<Comparative Example 9>

In the above Example 2, instead of the self-recovery layer of Example 2, a coating solution prepared by mixing 100 parts by weight of a polyester prepolymer, 35 parts by weight of a polyurethane prepolymer, and 70 parts by weight of an isocyanate compound was applied, and a self-recovery layer prepared to a thickness of 20 μm was included after heat curing, in the same manner as Example 2, except that the coating solution was applied.

<Comparative Example 10>

In the above Example 2, the self-recovery layer was manufactured in the same manner as in Example 2, except that the thickness was manufactured to be 7 um instead of 20 um.

<Comparative Example 11>

In the above Example 2, the self-recovery layer was manufactured in the same manner as in Example 2, except that the thickness was manufactured to be 65 um instead of 20 um.

The laminated films of the above examples and comparative examples were prepared for experiments by attaching them to a glass surface after removing the release film attached to the adhesive layer.

<Comparative Example 12>

To remove any contamination from the glass surface, apply a commercially available water-repellent coating agent (fluorine-based water-repellent agent) from Company A to a soft cloth and rub it evenly over the glass surface to ensure that the solution is evenly applied.

<Comparative Example 13>

After removing any contamination from the glass surface, spray the glass surface once with a commercially available B Company glass water-repellent coating agent (silicon-based water-repellent agent), and then evenly rub the glass surface with a soft cloth to ensure that the solution is evenly applied.

Experimental method

1. Contact angle measurement

1) Measuring device model name: Phoenix-MT(T) (S.E.O.) Contact angle measuring device

2) Measurement conditions and methods: Room temperature, sessile drop method --> Repeat measurements 5 times on different surfaces and record the average value.

2. Waterproofing Test

* Testing method

① Paint the surface of the water-repellent coating layer using an oil-based pen (Monami name pen).

② Wipe 3 times using the Kimtech Science Wiper

③ Visually observe the degree of wiping of the oil-based ink, evaluate it using the indicators below, and record it.

◎: Oil-based ink is completely erased, ○: Oil-based ink remains about 20%, △ Oil-based ink remains about 50%, X: Oil-based ink remains more than 90%

3. Wear Test

1) Measuring instrument model name: ASR-5600 (Guangdong Esery Instrument Technology Co., Ltd.) Wear tester

2) Measurement conditions and methods: Wear resistance test eraser (7017R) installed, weight load 500g, reciprocating length 50mm, speed 30 times/min, 3000 reciprocations

4. Slip test (friction coefficient measurement)

- Measuring device model name: FPT-F1 (labthink) friction coefficient measuring device

- Measurement conditions and methods: Measurement of dynamic friction coefficient, friction agent: PU, load: 200g

5. Self-healing test

* Testing method

① Create scratches on the film surface using a copper brush.

② Visually observe whether scratches are restored and record the time.

division appearance Self-healing Slipperiness Water repellent Waterproofing (visual observation) (Scratch recovery test) (Measurement of dynamic friction coefficient) (Contact angle measurement - comparison before and after wear test)
(unit) (Metal pen wiping test - comparison before and after wear test) Before wear test After wear test Before wear test After wear test Comparative Example 1 Good Restore immediately 0.21 99 - ○ - Example 1 Good Restore immediately 0.12 110 105 ◎ ◎ Example 2 Good Restore immediately 0.10 114 109 ◎ ◎ Example 3 Good Restore immediately 0.10 114 109 ◎ ◎ Example 4 Good Restore immediately 0.11 107 102 ◎ ○ Example 5 Good Restore immediately 0.13 105 101 ◎ ○ Example 6 Good Restore immediately 0.14 105 100 ◎ ○ Comparative Example 2 Good Restore immediately 0.19 98 - ○ - Comparative Example 3 Good Slow restore speed 0.22 95 - △ - Example 7 Good Restore immediately 0.13 110 105 ◎ ◎ Comparative Example 4 Good Restore immediately 0.12 112 97 ◎ △ Comparative Example 5 Good Restore immediately 0.13 108 95 ◎ △ Comparative Example 6 Good Slow restore speed 0.12 112 100 ◎ ○ Comparative Example 7 Good Not restored 0.13 110 98 ◎ △ Comparative Example 8 Good Slow restore speed - - - - - Comparative Example 9 Good Not restored - - - - - Comparative Example 10 Good Slow restore speed - - - - - Comparative Example 11 Self-healing layer coating surface curvature phenomenon Restore immediately - - - - - Comparative Example 12 Good (No self-healing layer) 0.12 110 87 ◎ X Comparative Example 13 Good (No self-healing layer) 0.16 103 75 ◎ X

In Table 1 above, samples with poor appearance and self-restoration, which are basic properties required for laminated films, were evaluated as defective due to insufficient basic functions, and no additional water-repellent tests, etc. were performed.

Referring to Table 1 above, Comparative Example 11 had a problem in that a bending phenomenon was formed on the self-restoring layer coating surface, and therefore, despite having self-restoring properties, it was evaluated as defective because it may cause a problem in that visibility is reduced when applied to automobile windshields, display glass, etc.

In the case of Comparative Examples 6 to 10, they were evaluated as defective because there was a problem of slow recovery speed or failure to recover after scratch formation.

It can be confirmed that the laminated film according to the embodiment has excellent appearance and visibility, while satisfying the properties of the basic laminated film with excellent self-restoration, and has excellent effects in slipperiness, water repellency, and stain resistance. In particular, when comparing the water repellency effect after the abrasion test with that of Comparative Examples 12 and 13, it can be confirmed that the water repellency and stain resistance of the laminated film of the embodiment are excellent even after the abrasion test.

In particular, it can be confirmed that Examples 2 and 3 have excellent characteristics in both water-repellent and antifouling effects before and after the wear test.

10: Self-healing layer
20: Anti-contamination coating layer
30: Elastic substrate layer
40: Adhesive layer
50: Heteromorphic film layer
60: Top surface adhesive protective film layer

Claims (5)

A self-recovering layer comprising a urethane resin; a contamination-preventing coating layer positioned on top of the self-recovering layer; an elastic substrate layer positioned on the bottom of the self-recovering layer; and an adhesive layer positioned on the bottom of the elastic substrate layer.
The above-mentioned anti-contamination coating layer comprises a water-repellent compound having a urethane bond,
The thickness of the above anti-pollution coating layer is 1 to 100 nm (nanometers),
The water-repellent compound having the above urethane bond has a structure of the following chemical formula 1, a laminated film:
<Chemical Formula 1>
Y-[-HNO=CO-[X-(A) _l -(B) _m -X']-OC=ONH-] _n -Y'
The above A is -(CF ₂ CF ₂ O)-, the above B is -(CF ₂ O)-,
The above l and m are each independently integers from 1 to 50,
The sum of the above l and m is 10 to 100,
The above n is an integer from 1 to 10.
The above X and X' are the same or different, and each independently represents one selected from a fluorinated C ₁ to C ₅ alkoxy group, a silane group primary substituted with a C ₁ to C ₃ alkyl, and a silane group secondary substituted with a C ₁ to C ₃ alkyl.
The above Y and Y' are the same or different, and are each independently one selected from a silane group primary substituted with a C ₁ to C ₃ alkyl, a silane group secondary substituted with a C ₁ to C ₃ alkyl, and a silane group tertiarily substituted with a C ₁ to C ₃ alkyl.
delete In the first paragraph,
A laminated film wherein the above-mentioned anti-contamination coating layer is formed of a water-repellent coating solution containing a water-repellent compound having a urethane bond and a fluorine-based solvent, and having a solid content of 0.05 to 1%.
In the first paragraph,
The self-recovering layer is a laminated film comprising a urethane resin manufactured by reacting a prepolymer obtained by mixing 100 parts by weight of a polyester prepolymer, 30 to 55 parts by weight of a polyurethane prepolymer, and 30 to 60 parts by weight of an isocyanate compound.
In the first paragraph,
The above adhesive layer comprises an acrylic adhesive and/or a silicone adhesive,
A laminated film having an adhesive strength of 50 to 1500 gf/in.