KR20230063411A - Window films that show photochromic properties depending on the day and night - Google Patents

Abstract

The present invention relates to a window film, and more particularly, to a window film having excellent shielding rate against ultraviolet rays and infrared rays, and capable of discoloration depending on the amount of external light or environmental conditions, thereby providing safe driving and convenience to the driver. It relates to vehicle and architectural window films.

Description

Window films that show photochromic properties depending on the day and night}

The present invention relates to a window film, and more particularly, to a window film having excellent shielding rate against ultraviolet rays and infrared rays, and capable of discoloration depending on the amount of external light or environmental conditions, thereby providing safe driving and convenience to the driver. It relates to vehicle and architectural window films.

Solar rays are largely divided into ultraviolet rays (100 ~ 380 nm), visible rays (380 ~ 780 nm), and infrared rays (780 ~ 60000 nm), and infrared rays are further divided into near infrared rays and far infrared rays. Of these, UV rays make up about 6%, visible rays about 46%, and infrared rays about 48%. UV rays cause skin aging and cancer when the skin is exposed for a long time, and infrared rays increase the indoor temperature. This causes an increase in cooling costs in the summer.

A window film refers to a film made of a high-tech material such as metal or ceramic having characteristics capable of controlling the amount of energy by solar rays flowing into an enclosed interior space through glass.

These window films are essentially used for window glass existing on the outer walls of automobiles, residential or commercial buildings, and block solar heat to create a more comfortable and pleasant driving, residential and office environment. In particular, since a vehicle directly receives solar heat by moving while driving and is greatly affected by solar heat even when stopped on the road for a long time without moving, the construction of a window film is essential.

Window film, often referred to as "vehicle tinting" (or window tinting as an accurate term), serves to protect people and objects inside the vehicle from damage caused by sunlight. In particular, it blocks UV protection to prevent glare, damage to the eyes and skin, protects vehicle interior materials from discoloration and deformation, and prevents secondary injuries by preventing scattering caused by glass breakage. do.

In recent years, due to climate change, such as an increase in average temperature due to global warming and destruction of the ozone layer due to environmental pollution, adverse effects caused by ultraviolet rays, infrared rays, or solar radiation energy have become increasingly serious.

In addition, as the quality of life, dependence on automobiles, and expected demand for the functions of automobiles increase year by year, not only the light blocking properties of vehicle window films, but also high quality, such as heat insulation, visibility, sound insulation, and privacy protection functions There is an increasing demand for technology development for more diverse functionalities such as, etc.

Republic of Korea Patent Registration No. 10-2164051

The present invention is to solve the above problems, while having excellent shielding rate against ultraviolet and infrared rays, discoloration is possible according to the amount of external light or environmental conditions, so that safe driving and convenience can be provided from the driver , vehicle and architectural window films.

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

The above object is a base layer of a transparent polymer resin; a light blocking layer located on the substrate layer and formed using a sputtering method; an overcoating layer located on the light blocking layer; a functional layer positioned on the overcoating layer; and a protective film located on the functional layer; Including, wherein the light blocking layer, a metal layer located on the substrate layer; and an infrared blocking layer including a metal alloy layer located on the metal layer; and

characterized in that it comprises a; ultraviolet ray blocking layer located on the infrared ray blocking layer and including a metal oxide layer of a nanostructure, wherein the functional layer comprises spiro-naphthoxazine, naphthopyran ( naphthopyran) and a photochromic material that is a mixture of triarylmethyne, characterized in that it has a photochromic film layer, it can be achieved by vehicle and architectural window films.

The UV blocking layer may include a zinc oxide nanowire layer positioned on the infrared blocking layer; and a titanium dioxide nanosheet layer formed on the zinc oxide nanowire layer, wherein a thickness ratio of the zinc oxide nanowire layer and the titanium dioxide nanosheet layer is 1.5 to 1.8 : 0.8 to 1.

According to the present invention, by providing the structural characteristics of the light blocking layer and the photochromic film layer, the shielding rate for ultraviolet rays and infrared rays is excellent, and discoloration is possible according to the amount of external light or environmental conditions, so that drivers can drive safely. It is possible to manufacture window films for vehicles and buildings that can provide comfort and convenience.

According to the present invention, the vehicle and architectural window films can exhibit a 100% UV blocking effect.

According to the present invention, the vehicle and architectural window films further include an anti-glare layer to improve the driver's appearance reflected in the window or the light reflection phenomenon in which the light of the interior light is reflected, thereby further improving the driver's visibility.

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

Hereinafter, the present invention will be described in detail with reference to embodiments and drawings of the present invention. These examples are only presented as examples to explain the present invention in more detail, and it will be apparent to those skilled in the art that the scope of the present invention is not limited by these examples. .

In addition, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of skill in the art to which this invention belongs, and in case of conflict, this specification including definitions of will take precedence.

In order to clearly explain the proposed invention in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are attached to similar parts throughout the specification. And, when a certain component is said to "include", this means that it may further include other components without excluding other components unless otherwise stated. Also, a “unit” described in the specification means one unit or block that performs a specific function.

In each step, the identification code (first, second, etc.) is used for convenience of description, and the identification code does not describe the order of each step, and each step does not clearly describe a specific order in context. It may be performed differently from the order specified above. That is, each step may be performed in the same order as specified, may be performed substantially simultaneously, or may be performed in the reverse order.

In the present invention, the term "on" or "on" used in relation to the stacking position between layers includes not only the case where a certain component is formed directly on top of another component, but also the case where a third component is interposed between these components. means to do

The 'window film' according to an embodiment of the present invention and this specification describes a window film for a vehicle, but is not limited thereto, and should be interpreted as a window film that can be applied to both vehicles and buildings.

Hereinafter, embodiments and examples of the present application will be described in detail. However, it may not be limited to these implementations and examples and drawings herein.

One aspect of the present application, a base layer of a transparent polymer resin; a light blocking layer located on the substrate layer and formed using a sputtering method; an overcoating layer located on the light blocking layer; Located on the overcoating layer, a functional layer; and a protective film located on the functional layer; It provides a vehicle and architectural window film comprising a.

First, the base layer serves as a support for the window film, and may have a visible light transmittance of 70% or more or 80% or more. As long as the above transmittance is satisfied, the material used for the light-transmitting substrate layer is not particularly limited.

Specifically, the base layer is formed of a transparent polymer resin so as not to obstruct the driver's vision, and is particularly preferably formed of a transparent ultraviolet curable resin. The base layer may be, for example, at least one selected from the group consisting of polyester, acrylic, cellulose, polyolefin, polyvinyl chloride, polycarbonate, phenol, and urethane. Among them, as the transparent polymer resin, acrylic, polyester, and polycarbonate resins having a good balance between heat resistance and flexibility are preferable, and biaxially stretched polyester and polycarbonate are more preferable.

The thickness of the base layer is not particularly limited, but may have a thickness of, for example, 5 μm or more, 10 μm or more, 20 μm or more, or 30 μm or more, and the upper limit thereof may be 200 μm or 150 μm.

The light blocking layer may include an infrared blocking layer and an ultraviolet blocking layer. Specifically, the light blocking layer may include an infrared blocking layer formed on one surface of the base layer and an ultraviolet blocking layer formed on the infrared blocking layer.

The infrared ray blocking layer transmits visible light but reflects near-infrared and far-infrared rays, thereby giving the window film high thermal insulation and high thermal insulation functions. The infrared blocking layer may be a single layer or a laminated structure in which two or more layers are stacked.

The infrared ray blocking layer may include a metal, a metal alloy, a metal oxide, or a combination thereof. Specifically, the infrared blocking layer may have a laminated structure including a metal layer, a metal alloy layer, a metal oxide layer, or a combination thereof.

The metal is titanium (Ti), tungsten (W), silver (Ag), platinum (Pt), gold (Au), copper (Cu), chromium (Cr), aluminum (Al), tin (Sn), palladium It may be any one selected from the group consisting of (Pd) and nickel (Ni).

The metal alloy may have one selected from the above-mentioned metal group as a main component, and may include another metal component from the above-mentioned metal group as a sub-component, or may include other unlisted components as a sub-component. In this case, the main component may mean a case in which the weight ratio occupied is 80% or more. The metal alloy may be, for example, a cesium-tungsten alloy or a tin-indium alloy.

The metal oxide may be, for example, antimony (Sb), barium (Ba), gallium (Ga), germanium (Ge), hafnium (Hf), indium (In), lanthanum (La), magnesium (Mg), Any one selected from the group of oxides of selenium (Se), silicon (Si), tantalum (Ta), titanium (Ti), vanadium (V), yttrium (Y), zinc (Zn), and tin (Sn) can

Preferably, the infrared blocking layer may include a structure in which a metal layer and a metal alloy layer are stacked. If the infrared blocking layer includes a metal layer and a metal alloy layer together, the light blocking part is formed in a multi-layer structure of 5 or more layers during the manufacturing of the existing window film to solve the complexity of the process, while reducing the infrared ray blocking efficiency and metal alloy. durability can be increased.

As an example, the infrared ray blocking layer, a metal layer formed from the direction of the substrate layer, for example, a nickel (Ni) layer; and a metal alloy layer formed on the metal layer, for example, a tin-indium alloy layer.

In the infrared blocking layer, the nickel layer and the tin-indium alloy layer may be formed to have a thickness ratio of 1.2 to 1.8:1, for example, 1.6:1. The range of the thickness ratio described above may further increase infrared ray blocking efficiency.

The method of forming the infrared ray blocking layer, specifically, the method of forming the metal layer, metal alloy layer or metal oxide layer, may use a sputtering method.

The sputtering method is to generate plasma by injecting sputtering gas into a chamber made of a vacuum atmosphere, and then collide particles in the plasma with a target material to form a film to cause the collision. It is a method of coating a material separated from a target by a substrate on a substrate. Generally, sputtering gas uses argon (Ar) as an inert gas. A sputter system uses a target as a cathode and a substrate as an anode.

When power is applied, the injected sputtering gas collides with electrons emitted from the cathode and is ionized (Ar+), and these ions are attracted to the target, which is the cathode, and collide with the target. The energy possessed by the ions is transferred to the target by this collision, atoms and molecules of the target material are emitted into the chamber, and the released target material is formed as a thin film on the substrate.

The thin film manufacturing technology using the sputtering method can precisely control the thickness of the coating layer up to several tens of nm, and can very easily process the partial coating process using a simple mask.

The UV blocking layer may include a metal oxide, and specifically, the metal oxide may be formed of a nanostructure. The UV blocking layer may be a single layer or a structure in which two or more layers are stacked. The nanostructure may mean, for example, a structure having a shape of a nanowire, nanosheet, nanotube, nanorod, or nanoflower. The metal oxide may be any one selected from the group consisting of titanium dioxide (TiO ₂ ), tungsten trioxide (WO _{3 )} , zinc oxide (ZnO), cerium dioxide (CeO ₂ ), and vanadium oxide (V ₂ O ₃ ). there is.

As an example, the UV blocking layer may include nanowires or nanosheets formed of titanium dioxide (TiO ₂ ), tungsten trioxide (WO _{3 )} , or zinc oxide (ZnO). Specifically, the UV blocking layer may include a nanowire formed of zinc oxide (ZnO), a nanosheet formed of titanium dioxide (TiO ₂ ), or a combination thereof. In the case of including a combination of the zinc oxide (ZnO) nanowires and titanium dioxide (TiO ₂ ) nanosheets, the zinc oxide nanowire layer and the titanium dioxide nanosheet layer may be formed in a stacked structure.

The zinc oxide nanowires and/or titanium dioxide nanosheets have the effect of blocking light in the UV region compared to powder or powder form by preparing zinc oxide and titanium dioxide, which are excellent in blocking light in the UV region, in a structure shape, respectively. can further increase.

A method of manufacturing the zinc oxide nanowires and/or titanium dioxide nanosheets may include, for example, forming a seed layer on a substrate and growing the nanowires or nanosheets as nanostructures on the seed layer. there is. Formation of the seed layer may be formed using a sputtering technique. Forming the nanostructure on the seed layer may be a general method used in the art, for example, a hydrothermal synthesis method.

The nanowire may have a length of 50 to 500 nm, specifically, 250 to 400 nm, and an average diameter of 10 nm to 80 nm, specifically, 20 nm to 60 nm. The nanosheet may have a thickness of 0.5 to 15 nm, specifically, 1 to 10 nm.

As an example, the UV blocking layer may include a zinc oxide nanowire layer formed on the aforementioned infrared blocking layer; and a titanium dioxide nanosheet layer formed on the zinc oxide nanowire layer. The total thickness of the UV blocking layer may be 25 to 100 nm, specifically, 30 to 80 nm. The thickness ratio of the zinc oxide nanowire layer and the titanium dioxide nanosheet layer may be 1.5 to 1.8 : 0.8 to 1. The thickness ratio within the above-mentioned range further increases the UV blocking efficiency so that a 100% UV blocking effect can be exhibited.

The overcoating layer may serve to maintain visible light transmittance and prevent damage to the light blocking layer, that is, the infrared blocking layer and the ultraviolet blocking layer. The material of the overcoating layer is not particularly limited, and materials commonly used in the field may be used without limitation. For example, the overcoating layer may include a cured product of a composition including a monofunctional or multifunctional photocurable organic compound and inorganic or organic particles.

The overcoating layer may have a thickness of 100 nm or less. If the thickness exceeds the above, the transmittance of the window film may decrease, and the infrared reflection function of the window film may decrease due to infrared absorption of the overcoating layer.

A protective film positioned on top of the overcoating layer may be further included. The protective film may protect the window film from an external force or external environment generated during handling, movement, or construction of the window film. The protective film may be peeled off from one side of the window film without damaging the overcoating layer during construction.

As the material of the protective film, a polymer film known in the related art may be used. For example, a polyester film such as polyethylene terephthalate or polybutylene terephthalate, a polytetrafluoroethylene film, a polyethylene film, a polypropylene film, a polybutene film, a polybutadiene film, a poly(vinyl chloride) film, or a polyimide film. A plastic film such as may be used. These films may be used as a single layer, or may be laminated together and used as multiple layers. Although not particularly limited, the thickness of the protective film may range from 10 μm to 100 μm.

A functional layer may be further included between the overcoating layer and the protective film. The functional layer may be, for example, a water repellent coating layer, a flame retardant layer, an anti-shattering layer, an anti-glare layer, a photochromic film layer, or a combination thereof. As an example, the functional layer may include an anti-glare layer; and a photochromic film layer formed on the anti-glare layer.

The anti-glare layer may include an acrylic binder, specifically, a urethane acrylate binder; inorganic components; And a coloring component; may include. The inorganic component and the pigment component may exhibit a matting effect.

The inorganic component is a single material or two or more selected from silica, amorphous titanium oxide, amorphous zirconium oxide, indium oxide, aluminum oxide, amorphous zinc oxide, amorphous cerium oxide, barium oxide, calcium carbonate, amorphous barium titanate, and barium sulfate. Composites and the like may be preferred. For example, the inorganic component may be a mixture of silica and aluminum oxide in a weight ratio of 1.5 to 2:1, for example, 1.8:1.

The pigment component may be, for example, nano-pigment carbon black. The particle size of the nano pigment may be 5 to 15 nm.

As an example, the anti-glare layer, 0.01 to 2.5 parts by weight of the inorganic component to 100 parts by weight of the urethane acrylate binder; and 0.01 to 1.5 parts by weight of the coloring component.

The method of forming the anti-glare layer is to coat a coating liquid containing the above-described components, and the coating method may be, for example, a slot die coater, gravure, or micro gravure. there is. After the coating, curing at a temperature of 80 to 100 ° C. for 5 seconds, or using one lamp selected from the group consisting of a UV lamp, a mercury-vapor lamp and a metal halide lamp Curing can be performed for 7 to 15 seconds.

Meanwhile, a release film may be further included on one side of the substrate layer, specifically, on one side opposite to the light blocking layer. The release film may be attached on one side of the substrate layer via a pressure-sensitive adhesive layer. After removing the release film, the pressure-sensitive adhesive layer may adhere the window film to the glass of the vehicle.

The release film serves to temporarily protect the pressure-sensitive adhesive layer that attaches the window film to the glass, and the type of substrate is not particularly limited as long as it can perform the function. As long as the pressure-sensitive adhesive layer is a composition capable of forming a pressure sensitive adhesive (PSA) having peelable properties, specific components thereof are not particularly limited. For example, as the pressure-sensitive adhesive, an acrylic pressure-sensitive adhesive, a urethane pressure-sensitive adhesive, a silicone pressure-sensitive adhesive, or a rubber-based pressure-sensitive adhesive may be used.

The photochromic film layer, including a photochromic material, may exhibit a characteristic in that the amount of discoloration increases according to the intensity of ultraviolet rays. The photochromic film layer may include, specifically, the photochromic material, monomer, crosslinking agent, polymerization initiator, photochromic dye, light stabilizer, or other additives alone or in combination of two or more on a substrate film for bonding. can

The base film may be, for example, a polyvinyl butyral (PVB) film or an ethyl vinyl acetate (EVA) film.

The photochromic material is spiro-naphthoxazine, naphthopyran, triarylmethane, stilbene, azastilbene, nitrone, fulgide, spiro-ox Photo, quinone, azobenzene or diarylethene, but not necessarily limited thereto, and includes all known photochromic materials. More preferably, in the present invention, the photochromic material may be a mixture of spiro-naphthoxazine, naphthopyran, and triarylmethyne.

As the monomer, an acrylic resin derivative may be used, and examples thereof include BP-4PA (PO-modified bisphenol A diacrylate), methyl methacrylate, and hydroxyethyl methacrylate, but are not necessarily limited thereto. The crosslinking agent serves to improve weather resistance and transparency by strengthening polymer bonds, and p,p'-bis(acryloyloxy)benzophenone is a representative example. As the polymerization initiator, V-65 (2,2-azobis(2,4-dimethylbalenonitrile)) is used as a catalyst for polymerizing the matrix monomer into a polymer. The photochromic dye plays a role in adjusting the color, and palatinate purple is used. The light stabilizer serves to prevent yellowing of the polymer by ultraviolet rays, and Tnuvin 144 is used.

The photochromic film layer may have a thickness of 0.1 to 10 mm, specifically, 0.1 to 2 mm, for example, 1 mm. The photochromic film layer has an external ultraviolet intensity range of 10 to 4000 μW/cm ² , more specifically, 100 to 3000 μW/cm ² , so that the photochromic film can be discolored by absorbing wavelengths of ultraviolet rays. do. As a result, the color changes to a little darker outdoors during the day and changes to a brighter color at night, on a cloudy day, or in a place where light is blocked, for example, in an underground parking lot, thereby providing drivers with safe driving and convenience.

In this specification, only a few examples of various embodiments performed by the present inventors are described, but the technical spirit of the present invention is not limited or limited thereto, and can be modified and implemented in various ways by those skilled in the art, of course.

Claims (2)

A base layer of a transparent polymer resin;
a light blocking layer located on the substrate layer and formed using a sputtering method;
an overcoating layer located on the light blocking layer;
Located on the overcoating layer, a functional layer; and
Located on the functional layer, a protective film; including,
The light blocking layer may include: a metal layer positioned on the base layer; and an infrared blocking layer including a metal alloy layer positioned on the metal layer; and
characterized in that it comprises a; ultraviolet ray blocking layer located on the infrared ray blocking layer and including a metal oxide layer of a nanostructure,
Characterized in that the functional layer includes a photochromic film layer comprising a photochromic material that is a mixture of spiro-naphthoxazine, naphthopyran and triarylmethyne, Window films for automotive and architectural applications. According to claim 1,
The UV blocking layer,
Located on the infrared blocking layer, a zinc oxide nanowire layer; And a titanium dioxide nanosheet layer formed on the zinc oxide nanowire layer;
The thickness ratio of the zinc oxide nanowire layer and the titanium dioxide nanosheet layer is 1.5 to 1.8: 0.8 to 1, characterized in that, window film for vehicles and construction.