CN116343612A - Decorative film and decorative laminated structure - Google Patents

Abstract

The invention provides a decorative film and a decorative laminated structure which can give consideration to both visibility and concealment of an appearance design. A decorative film has a front surface layer and a light shielding layer partially provided on the back side of the front surface layer, the decorative film has a light shielding region having the light shielding layer and having an optical density of 5.3 or more and a light transmitting region having no light shielding layer, and the front surface layer has an optical density of 0.8 or more and 1.5 or less.

Description

Decorative film and decorative laminated structure

technical field

The present invention relates to a decorative film and a decorative laminated structure. Specifically, it relates to a decorative film and a decorative laminated structure applicable to a light-emitting unit.

Background technique

Conventionally, a light-emitting device installed inside a vehicle is known. For example, Patent Document 1 discloses a light-emitting unit for a vehicle, which includes a light-emitting area provided in an interior space of the vehicle, and makes the light-emitting area emit light. , and the vehicle light-emitting unit includes: an illuminating body for illuminating light; a transmissive body disposed in front of the illuminating body to transmit the light irradiated from the illuminating body; a decorative body disposed on the transmissive body The position in front of the exposed surface of the light-emitting region that is exposed in the internal space is formed; and the control unit controls the illuminating body. During the period when the light-emitting region does not emit light, the decorative body forms The decoration pattern of the exposed surface of the light-emitting region is a pattern corresponding to the decoration pattern of the exposed surface of the non-light-emitting region adjacent to the light-emitting region, and the control unit controls the irradiating body while the light-emitting region is emitting light. Control is performed so that the light-emitting part moves regularly on the exposed surface of the light-emitting region.

[Prior art literature]

[Patent Document]

[Patent Document 1] Japanese Patent Laid-Open No. 2020-104852

Contents of the invention

[Problem to be Solved by the Invention]

The inventors of the present invention have studied a decorative film that, for example, when used by sticking to a transparent base material that includes a light source inside, can visually recognize the design when the light source is turned on, and can be used when the light source is turned off. Difficult to visually identify the design. Such a decorative film needs to visually recognize the design clearly when the light source is turned on. However, only by providing a light-transmitting region that transmits light and a light-shielding region that blocks light on the decorative film, the design can be visually recognized even when it is turned off, and there is room for further research.

The present invention has been made in view of the above situation, and an object of the present invention is to provide a decorative film and a decorative laminated structure capable of maintaining the appearance of the design and its surroundings when the light source is turned off, in addition to the visibility of the design when the light source is turned on. The concealment of the partially coordinated and not easily visually recognizable exterior design.

[Technical means to solve the problem]

In order to make it difficult to visually recognize the design when the light source is turned off, the present inventors focused on concealing it using a semi-transmissive film. Furthermore, it was found that by arranging a semi-transmissive film as the front surface layer on the side where the design is visually recognized, the design can be made less visible when the light source is turned off. Furthermore, it was found that by making the optical density of the light-shielding region equal to or greater than a certain value, light can be sufficiently shielded when the light source is turned on. On the other hand, it can be seen that if the optical density of the semi-transmissive film is increased, the design becomes less visible when the light source is off, but the design becomes less visible when the light source is on. Therefore, the inventors have found that by adjusting the optical density of the semi-transmissive film within a certain range, both the concealment of the design when the light source is off and the visibility of the design when the light source is on are compatible, and completed the present invention.

The decorative film of the present invention has a front surface layer and a light-shielding layer, the light-shielding layer is partially provided on the back side of the front surface layer, and the decorative film has a light-shielding region and a light-transmitting region, and the light-shielding region has the The light-shielding layer has an optical density of 5.3 or more, the light-transmitting region does not have the light-shielding layer, and the optical density of the front surface layer is 0.8 or more and 1.5 or less.

The decorative film of the present invention also has a front surface layer, a light-shielding layer, and a back layer, the light-shielding layer is partially arranged between the front surface layer and the back surface layer, and the decorative film has a light-shielding region and a light-transmitting layer. In an area, the light-shielding area has the light-shielding layer and has an optical density of 5.3 or more, the light-transmitting area does not have the light-shielding layer, and the optical density of the front surface layer is 0.8 or more and 1.5 or less.

In the decorative laminated structure of the present invention, the decorative film is laminated and integrated on a base material, and the base material is arranged on the back side of the decorative film.

[Effect of the invention]

The decorative film and the decorative laminated structure of the present invention can take into account the visual recognition and concealment of the appearance design.

Description of drawings

FIG. 1 is a schematic cross-sectional view showing an example of a first decorative film of the present invention.

Fig. 2 is a perspective view of an example of the first decorative film shown in Fig. 1 viewed from the back side.

Fig. 3 is a schematic cross-sectional view showing an example of the second decorative film of the present invention.

Fig. 4 is a schematic cross-sectional view showing another example of the second decorative film of the present invention.

Fig. 5 is a schematic cross-sectional view showing an example of the decorative laminated structure of the present invention.

Fig. 6 is a schematic cross-sectional view showing an example of a light emitting unit using the decorative laminated structure shown in Fig. 5 .

Fig. 7 is a schematic front view of the light emitting unit shown in Fig. 6 viewed from the front surface side when the light source is turned off.

8 is a schematic front view of the same light-emitting unit as that shown in FIG. 6 viewed from the front surface side when the light source is turned on.

Fig. 9 is a schematic diagram for explaining a method of measuring optical density.

[explanation of the symbol]

1: Translucent area

2: shading area

20: semi-permeable membrane

30: basement membrane

40: Adhesive layer

50: Bottom

60: top film

70: Damage Resistant Coating

100A: First decorative film

100B1, 100B2: Second decorative film

110: front surface layer

120: shading layer

130: back layer

200: Substrate

210: light source

300: Decorative laminated structure

400: light emitting unit

Detailed ways

The first decorative film of the present invention has a front surface layer and a light-shielding layer, the light-shielding layer is partially provided on the back side of the front surface layer, and the first decorative film has a light-shielding region and a light-transmitting region, and the light-shielding layer The area has the light-shielding layer and has an optical density of 5.3 or more, the light-transmitting area does not have the light-shielding layer, and the optical density of the front surface layer is 0.8 or more and 1.5 or less.

The second decorative film of the present invention has a front surface layer, a light-shielding layer, and a back layer, the light-shielding layer is partially disposed between the front surface layer and the back surface layer, and the second decorative film has a light-shielding region and a light-transmitting region, the light-shielding region has the light-shielding layer and has an optical density of 5.3 or more, the light-transmitting region does not have the light-shielding layer, and the optical density of the front surface layer is 0.8 or more and 1.5 or less.

FIG. 1 is a schematic cross-sectional view showing an example of a first decorative film of the present invention. Fig. 2 is a perspective view of an example of the first decorative film shown in Fig. 1 viewed from the back side. The first decoration film 100A includes a light shielding layer 120 and a semi-transmissive film 20 as the front surface layer 110 . The light shielding layer 120 is partially provided on the back side of the semi-transmissive film 20 . In this specification, the front surface side refers to the viewer's side when the decorative film and the base material are laminated and integrated for use, for example. In addition, the back side means the side opposite to the said front side.

In the decorative film of the present invention, the light-shielding layer may or may not be in contact with the front layer as long as it is provided on the back side of the front layer, but is preferably in contact. Another layer, for example, a layer containing an adhesive or a primer may be interposed between the light-shielding layer and the front surface layer or the back surface layer described later.

The reason why the light-shielding layer is partially provided is to form a design by having a part provided with a light-shielding layer and a part not provided with a light-shielding layer. That is, "partially" as used here means partially in the plane direction.

In the decorative film of the present invention, the light-shielding region refers to a region where light is blocked by the light-shielding layer when light is irradiated from the back side of the decorative film due to having a light-shielding layer, and the light-transmitting region refers to a region where light is blocked by the light-shielding layer because there is no light-shielding layer. Similarly, the regions through which the light is transmitted refer to regions in the plane direction, respectively.

Since the decorative film of the present invention has both the light-shielding region and the light-transmitting region, the light irradiated from the back side generates contrast, whereby the design can be visually recognized. That is, the shadow-picture-like design in which the light-shielding region becomes a shadow can be visually recognized. In addition, as will be described later, although the front surface layer also has a certain optical density, it is not regarded as a light-shielding layer, and only when the front surface layer exists in a certain area, it is not a light-shielding area.

In the example shown in FIG. 2 , the light-transmitting region 1 transmits light irradiated from the back side of the decorative film to visually recognize the shape of the star-shaped design. The shape of the design in the present invention is not particularly limited, and may be patterns, characters, graphics, and the like. In addition, the shape of the light-transmitting region may be the shape of the above-mentioned design, or may be its reversed form.

Regarding the optical density described later, the optical density of the light-transmitting region 1 is lower than that of the light-shielding region 2 . The optical density of the light-transmitting region 1 is a value close to the optical density of the front surface layer, for example, less than the optical density of the front surface layer+0.2, and further smaller than the optical density of the front surface layer+0.1.

The material constituting the light-shielding layer in the decorative film of the present invention is not particularly limited as long as it can shield light. For example, the light-shielding layer can be formed of a film or film containing a resin containing various pigments or dyes.

The thickness of the light-shielding layer is preferably 1 μm or more and 20 μm or less because it is difficult to obtain sufficient light-shielding properties if it is too thin, and since the concealment of the design described later may be impaired when it is too thick.

In order to partially provide the light-shielding layer, it is preferable to use an ink composition as a constituent material of the light-shielding layer. For example, by printing an ink composition using various printing methods on the back surface of a resin film constituting the front surface layer, a light shielding layer can be easily provided on a desired portion. The unprinted part (such as the blank part in FIG. 2 ) corresponds to the light-transmitting region.

The printing method is not particularly limited, and gravure printing, offset printing, flexographic printing, screen printing, etc. can be used, and gravure printing is preferable from the viewpoint of good printability on resin films such as vinyl chloride resin films. Specifically, gravure printing generally uses oil-based ink, and printing is performed by a gravure with a smooth surface of a printing plate. Therefore, the adhesion to a resin film with high smoothness is high, and the adhesion of the ink is stable.

As the ink composition, it is preferable to use a dark-colored ink composition in terms of excellent light-shielding properties, and for example, a black oil-based ink can be used. As such a black oil-based ink, a solvent-based gravure printing ink is preferable, for example, 794R ink of Lamic (LAMIC) (registered trademark) SR manufactured by Dainichi Seika Co., Ltd., Toyo Ink SC Holdings ( Panneco (registered trademark) manufactured by Toyo Ink SC Holdings Co., Ltd. and the like.

In the decorative film of the present invention, the light-shielding region has an optical density of 5.3 or more, preferably 5.5 or more. By setting the optical density of the light-shielding region to 5.3 or more, light can be sufficiently shielded when the light source is turned on from the back side of the decorative film to irradiate light. If the optical density of the light-shielding area is less than 5.3, there is a case where light leaks through the light-shielding area when the light source is turned on, and the contrast with the light-transmitting area decreases, thereby impairing the decorative film when the light source is turned on. Designability. As a method of adjusting the optical density of the light-shielding region, for example, when the light-shielding layer is provided by printing as described above, the optical density can be increased by increasing the number of times of printing and overlapping ink. In addition, the optical density when the light-shielding property is the lowest is 0, and the optical density when the light-shielding property is the highest is 6 (the upper limit of detection). Therefore, the upper limit of the optical density in the present invention is 6.

Fig. 9 is a schematic diagram for explaining a method of measuring optical density. Optical density (D) is represented by the following formula (1). In the following formula (1), T is the ratio of the transmitted light I to the incident light I ₀ represented by the following formula (2), that is, the transmittance. The measured value measured without the sample shown in FIG. 9 is assumed to be I ₀ =I. I ₀ is the light transmitted through the amber filter (Amber Filter) from the lamp. As a measurement device including a lamp and an amber filter, for example, a table-top transmission densitometer 361T (manufactured by X-Rite Corporation) can be used.

Optical density (D) = log ₁₀ (1/T) (1)

T=I/I ₀ (2)

If the transmittance T is converted into the optical density D, then additivity is established. Therefore, for example, when two films having an optical density of _Dx are superimposed, or the thickness of the film is doubled, the optical density is doubled as _2Dx . For example, when a film with an optical density of D _x and a film with an optical density of D _Y are stacked one by one, the optical density is D _X +D _Y . Among them, the optical densities are all established within the range not exceeding the upper limit value of 6. Therefore, for the optical density of the light-shielding area, not only the light-shielding layer plays a role, but also the front surface layer. For example, when the optical density of the front layer is 0.8, if the optical density of the light shielding layer provided on the back side is 4.5 or more, the optical density of the light shielding region can be 5.3 or more.

In the decorative film of the present invention, since the light shielding layer is provided on the back side of the front surface layer, the front surface layer is arranged on the front surface side of the light shielding layer. By arranging the front layer on the front side of the light-shielding layer, it becomes difficult for the observer to recognize the thickness of the light-shielding layer. Therefore, when light is not irradiated from the back side of the decorative film, it is difficult to visually recognize the design, that is, the concealment of the design can be improved. Conversely, when the light-shielding layer is arranged on the front side of the front surface layer, the design can be easily recognized even when light is not irradiated from the back side of the decorative film due to the thickness of the light-shielding layer. In addition, unless otherwise specified below, the concealment of the design refers to the concealment of the design when no light is irradiated from the back side of the decorative film, and the visibility of the design refers to the time when light is irradiated from the back side of the decorative film. The visual recognizability of the exterior design.

In the decorative film of the present invention, the optical density of the front surface layer is not less than 0.8 and not more than 1.5. By making the optical density of the front surface layer into the said range, both the concealability of the design of a decorative film and the visibility of a design can be made compatible. If the optical density of the front surface layer is less than 0.8, the design will be easily recognized even when light is not irradiated from the back side of the decorative film, and the concealment of the design of the decorative film will decrease. On the other hand, if the optical density of the front surface layer exceeds 1.5, the amount of light transmitted through the light-transmitting region decreases, so it is difficult to visually recognize the design when light is irradiated from the back side of the decorative film. Reduced visibility. The optical density of the front surface layer preferably satisfies the above numerical range over the entire area observed when the decorative film is used, and is preferably substantially uniform over the entire area. In addition, the optical density of the front surface layer can be measured by the same method as the optical density of the above-mentioned light-shielding region.

The constituent material of the front surface layer in the decorative film of the present invention is not particularly limited, but is preferably composed mainly of a resin film. By containing appropriate amounts of various colorants in the resin film, it is easy to adjust the optical density to a desired range, and it is easy to adjust the optical density substantially uniformly over the entire area.

The front surface layer may be composed of a single layer or may be composed of two or more layers. The front surface layer may also contain a layer containing an adhesive, a primer, or the like. The front surface layer may have a coating layer on the front surface side for imparting damage prevention and other functions.

The thickness of the front surface layer is preferably 50 μm or more and 300 μm or less. When the thickness of the front surface layer is too thin, the concealment of the design may be impaired. On the other hand, if the front surface layer is too thick, heat may be insufficient or the processing speed may be reduced when the front surface layer is thermally laminated with another layer. In addition, since the overall thickness of the decorative film increases, the workability when the decorative film is integrated with the base material may decrease. A more preferable lower limit of the thickness of the front surface layer is 70 μm, and a more preferable upper limit is 200 μm.

When a resin film is used for the front surface layer, the thickness of each of the resin films is preferably 50 μm or more and 150 μm or less. When the thickness of each said resin film is less than 50 micrometers, calender molding may become difficult. Concretely, if foreign matters, resin deterioration products generated during processing, etc. are mixed, the resin film may be cracked or have holes during calender molding. On the other hand, when the said thickness exceeds 150 micrometers, when thermally laminating with another film etc., heat may run short, or processing speed may fall. In addition, since the thickness of the decorative film as a whole increases, processability when the decorative film and the base material are laminated and integrated may decrease. A more preferable lower limit of the thickness of each resin film used for the front surface layer is 70 μm, and a more preferable upper limit is 100 μm. In addition, of course, two or more same or different resin films may be used to constitute the front surface layer.

In the case where the front surface layer is mainly composed of a resin film, the resin film is preferably a semi-transmissive film containing a resin component and a colorant. In this specification, the term semi-transmissive film does not block most of the incident light like a light-shielding layer, but is used in the meaning of a film that transmits a certain amount of light, and does not mean that solid, liquid, gas Such materials are used in the meaning of semi-transmissive film.

By adding a colorant to the semi-transmissive film, the optical density of the semi-transmissive film can be adjusted. As the colorant, a black colorant containing carbon black or the like is preferable. The semi-transmissive film may contain a colorant of another color, a colorant of a pearl tone, or the like in addition to a black colorant.

The content of the black colorant is preferably not less than 1.5 parts by weight and not more than 2.5 parts by weight relative to 100 parts by weight of the resin component. By setting the content of the black colorant within the above-mentioned range, the optical density of the semi-transmissive film can be adjusted to a preferable range in terms of constituting the front surface layer.

As the resin component, vinyl chloride resin is preferable. When the resin film of the present invention is attached to a substrate, the vinyl chloride resin film containing vinyl chloride resin as a main resin component follows the surface shape of the substrate due to its good elongation and is not easily broken. In addition, when pasting on a base material for lamination and integral molding, it can be molded at a relatively low temperature (about 120°C). Containing a vinyl chloride resin as a main resin component means that the content of the vinyl chloride resin in the entire resin components contained in the vinyl chloride resin film is 50% by weight or more. In addition, "lower temperature" means that it is lower than the molding temperature (over 130° C.) when molding resins other than vinyl chloride resins and acrylic resins (for example, polyethylene terephthalate).

Examples of the vinyl chloride resin include homopolymers of vinyl chloride and copolymers of vinyl chloride and other monomers.

Examples of such other monomers include vinyl esters such as vinyl acetate and vinyl propionate; olefins such as ethylene, propylene, and styrene; methyl acrylate, ethyl acrylate, and methyl methacrylate; (Meth)acrylic acid esters; maleic acid diesters such as dibutyl maleate and diethyl maleate; fumaric acid diesters such as dibutyl fumarate and diethyl fumarate; acrylonitrile, Vinyl cyanides such as methacrylonitrile; vinyl halides such as vinylidene chloride and vinyl bromide; vinyl ethers such as methyl vinyl ether and ethyl vinyl ether, etc. These monomers may be used alone or in combination of two or more.

The content of the other monomers in the copolymer is usually 50% by weight or less, preferably 10% by weight or less. When it exceeds 50 weight%, the bending resistance of a film may fall. Among the vinyl chloride resins, a homopolymer of vinyl chloride is preferable in that dimensional stability can be obtained.

The average degree of polymerization of the vinyl chloride resin may be 750-1300, for example. The preferable lower limit of the said average degree of polymerization is 800. When the average degree of polymerization is in the range of 750 to 1300, the formability at relatively low temperature is good. On the other hand, when the average degree of polymerization is less than 750, when the decorative film of the present invention is laminated and integrally formed with a base material, the film may not be sufficiently stretched to follow the shape of the base material. On the other hand, when the average degree of polymerization exceeds 1300, processability in calender molding for obtaining a vinyl chloride resin film decreases, and the appearance of the film surface may deteriorate. In addition, the shrinkage rate of the formed film becomes large, and it may be difficult to maintain the shape. The average degree of polymerization of the vinyl chloride resin refers to the average degree of polymerization measured according to Japanese Industrial Standards (Japanese Industrial Standards, JIS) K6721 "Testing Methods for Vinyl Chloride Resins".

The vinyl chloride resin film preferably contains a plasticizer. The content of the plasticizer is preferably not less than 7 parts by weight and not more than 35 parts by weight relative to 100 parts by weight of the vinyl chloride resin. By setting the content of the plasticizer within the above range, flexibility or moldability suitable for calendering or the like is obtained. In addition, an elongation suitable for vacuum, pressure forming, or the like when the decorative film of the present invention is attached to a base material is obtained. When the content of the plasticizer is less than 7 parts by weight, the vinyl chloride resin film becomes too hard, and the film may be broken during molding. On the other hand, when it exceeds 35 weight part, a vinyl chloride resin film may become too soft and handleability may fall. The more preferable minimum of content of the plasticizer with respect to 100 weight part of vinyl chloride resins is 15 weight part, and a more preferable upper limit is 30 weight part.

As the plasticizer, for example, bis(2-ethylhexyl) phthalate (Dioctyl Phthalate, DOP), diisononyl phthalate (Diisononyl Phthalate , DINP), diisodecyl phthalate (Diisodecyl phthalate, DIDP), phthalate di-undecyl phthalate (diundecylphthalate, DUP) and other phthalate diesters; dioctyl adipate, Dioctyl sebacate and other aliphatic dibasic acid diesters; tricresyl phosphate, trioctyl phosphate and other phosphate triesters; epoxy plasticizers such as epoxidized soybean oil and epoxy resin; polymer polyester plasticizer etc. Among them, phthalic acid diester is preferable. DUP is preferable in terms of not being restricted by various environments, less odor during film forming, and less pollution to the forming machine during film forming.

Fig. 3 is a schematic cross-sectional view showing an example of the second decorative film of the present invention. As shown in FIG. 3 , the second decoration film 100B1 has the semi-transmissive film 20 as the front surface layer 110 , the light shielding layer 120 , and the base film 30 as the back surface layer 130 in sequence. In the second decorative film of the present invention, since the light shielding layer is partially provided between the front surface layer and the back surface layer, it has the front surface layer, the light shielding layer, and the back surface layer in this order.

Although it does not specifically limit as a constituent material of the back surface layer in the decorative film of this invention, It is preferable to consist mainly of a resin film. The back layer may be composed of a single layer or may be composed of two or more layers. The back layer may also contain a layer containing an adhesive, a primer, or the like. The back layer may also have a coating layer that imparts color to transmitted light, or the like.

The back layer can give desired thickness or strength to the decorative film of the present invention. In addition, the back layer can be used as a base for providing a light-shielding layer. For example, the light-shielding layer can be provided by printing with ink on the surface of the resin film constituting the back layer. Preferably, the back layer is in contact with the light shielding layer. In addition, it is preferable that the back surface layer is in contact with the front surface layer in the portion where the light shielding layer is not provided. In addition, the thickness of the said front surface layer means the thickness from the observer's side surface of a light-shielding layer to the observer's side surface of the front surface layer.

The thickness of the back layer is preferably not less than 50 μm and not more than 250 μm. A more preferable lower limit of the back layer is 70 μm, and a more preferable upper limit is 200 μm.

For example, when a resin film such as the base film 30 in FIG. 3 is used to constitute the back layer, the thickness of each resin film is preferably 50 μm or more and 150 μm or less. A more preferable lower limit of the thickness of each resin film is 70 μm, and a more preferable upper limit is 100 μm.

The resin film constituting the back layer preferably contains vinyl chloride resin. As the vinyl chloride resin, the same vinyl chloride resin as that exemplified in the description of the front surface layer can be used.

The vinyl chloride resin film used for the back layer preferably contains a plasticizer. As the plasticizer, the same ones as those exemplified in the description of the front surface layer can be used. The content of the plasticizer is also the same as that described in the description of the front surface layer.

The back layer is preferably a highly transparent layer so as not to block light irradiated from the back side of the decorative film and transmitted through the light-transmitting region as little as possible. Specifically, it is preferable that the total light transmittance of the back layer is 80% or more. Therefore, the resin film used for the back layer is preferably a resin film having high transparency, specifically, a total light transmittance of 80% or more. In addition, in this specification, total light transmittance is a value based on JISK7375.

Fig. 4 is a schematic cross-sectional view showing another example of the second decorative film of the present invention. As shown in FIG. 4 , the second decorative film 100B2 preferably has an adhesive layer 40 on the back side of the base film 30 as the back layer 130 .

The adhesive layer 40 is not particularly limited, and an adhesive layer containing an adhesive such as an acrylic adhesive, a rubber adhesive, or a silicone adhesive can be used. Among these, acrylic adhesives are preferable in terms of excellent adhesiveness, workability, heat aging resistance, moisture aging resistance, and weather resistance, and relatively inexpensive.

The acrylic adhesive is an adhesive containing an acrylic polymer. The adhesive layer 40 may contain known crosslinking agents such as isocyanate curing agents and epoxy curing agents.

The thickness of the adhesive layer 40 is preferably not less than 20 μm and not more than 70 μm. A more preferable lower limit of the thickness of the adhesive layer 40 is 30 μm, and a more preferable upper limit is 55 μm. It is preferable that the adhesive layer 40 does not lower the transparency of the back layer, and the thickness of the adhesive layer is also preferably within the above-mentioned range in this respect.

On the back of the adhesive layer 40, although not shown in FIG. 4, it is preferable to add a spacer for protecting the adhesive layer. The spacer is peeled off when the decorative film is used, and it only needs to be peeled off immediately before sticking to the base material. The spacer is not particularly limited, and examples thereof include polyester, polyvinyl chloride, and polyvinyl chloride that have been subjected to easy-release treatment by coating silicone resin, fluororesin, or the like on the surface in contact with the adhesive layer 40 . Dichloroethylene, polyethylene terephthalate, polypropylene and other resin films (release film); high-quality paper, cellophane and other paper (release paper), etc.

The back layer may also have a bottom layer 50 between the base film 30 and the adhesive layer 40 . By providing the base layer 50, the adhesiveness of the base film 30 and the adhesive layer 40 can be improved. In addition, in the case of forming the light-shielding layer 120 with ink, the ink may permeate if it is in contact with the bottom layer, so it is preferable to have a structure in which the bottom layer 50 is not in contact with the light-shielding layer 120 (for example, according to the light-shielding layer 120, the base film 30, the bottom layer 50, the sequential configuration of the adhesive layer 40).

As shown in FIG. 4 , the second decorative film 100B2 may have a top film 60 on the front side of the semi-transmissive film 20 to form a front layer. In order not to block the light passing through the light-transmitting region 1 as much as possible, the top film 60 is preferably a film with high transparency, specifically, a total light transmittance of 80% or more. However, it is only necessary to make the optical density of the front surface layer within a predetermined range by combining with the semi-transmissive film 20 .

The thickness of the top film 60 is preferably not less than 50 μm and not more than 150 μm. A more preferable lower limit of the thickness of the top film 60 is 70 μm, and a more preferable upper limit is 100 μm.

As the top film 60, various resin films can be used, but a resin film containing vinyl chloride resin is preferable. As the vinyl chloride resin, the same vinyl chloride resin as that exemplified in the description of the front surface layer can be used.

The vinyl chloride resin film used for the top film 60 preferably contains a plasticizer. As the plasticizer, the same ones as those exemplified in the description of the front surface layer can be used. The content of the plasticizer is also the same as that described in the description of the front surface layer.

Although not shown, the front surface layer may have a surface design layer between the semi-transmissive film 20 and the top film 60 . The surface design layer is a layer that forms a design that can be seen even when the lights are turned off.

The front surface layer may also have a scratch-resistant coating 70 on the surface of the top film 60 on the front surface side. The scratch-resistant coating layer 70 is a layer that protects the surface of the second decoration film 100B2.

The scratch-resistant coating 70 may contain resin components such as urethane-based, acrylic-based, polyester-based, and the like. In addition, inorganic fillers such as silica, alumina, calcium carbonate, talc, kaolin, and glass fibers, and organic fillers such as acrylic resins and polycarbonates may also be contained.

The thickness of the scratch-resistant coating layer 70 is preferably not less than 1 μm and not more than 20 μm. When the thickness of the scratch-resistant coating layer 70 is less than 1 μm, sufficient scratch resistance may not be obtained. On the other hand, when the thickness of the scratch-resistant coating layer 70 exceeds 20 μm, the flexibility of the second decorative film 100B2 may decrease. A more preferable lower limit of the thickness of the scratch-resistant coating layer 70 is 2 μm, and a more preferable upper limit is 10 μm. The damage-resistant coating layer 70 is preferably not to reduce the transparency of the front surface layer, and in this regard, the thickness of the damage-resistant coating layer 70 is also preferably within the above-mentioned range.

If necessary, surface processing such as embossing may be given to the front surface layer. By imparting an embossed shape (concave-convex shape) to the surface of the front surface layer, a desired texture can be imparted to the decorative film. For example, patterns such as plain weave, twill weave, etc. can be imparted.

The semi-transmissive film 20 , the base film 30 , and the top film 60 may contain additives such as stabilizers, ultraviolet absorbers, processing aids, and modifiers as needed.

The decorative laminated structure of the present invention is constituted by laminating and integrating the decorative film of the present invention with various base materials. In the decorative laminated structure, the base material is arranged on the rear side of the decorative film. Fig. 5 is a schematic cross-sectional view showing an example of the decorative laminated structure of the present invention. The decorative laminated structure 300 of the present invention includes a base material 200 and a second decorative film 100B2 of the present invention disposed on the front side of the base material 200 .

The base material used in the decorative laminated structure of the present invention is not particularly limited, and examples include interior members of vehicles such as motorcycles and automobiles; member plates of household products such as furniture and home appliances, and the like.

The material constituting the base material is not particularly limited, for example, polycarbonate resin, acrylic resin, styrene resin, acrylonitrile-butadiene-styrene (acrylonitrile-butadiene-styrene, ABS) Resin, polypropylene (Polypropylene, PP) resin and other resins; iron, copper, aluminum and other metals; alloys, etc., medium density fiber (MediumDensity Fiber, MDF) board and other wood.

In the base material, at least a portion overlapping the light-transmitting region of the decorative film is preferably formed of a transparent material, and the entire base material may be formed of a transparent material. As the total light transmittance of the base material used in the decorative laminated structure of the present invention, it is preferable that the total light transmittance in the region overlapping the light-transmitting region of the decorative film to transmit light irradiated from the back side of the decorative film is More than 80%.

In order to form the decorative laminated structure of the present invention, for example, lamination and integration can be performed by bonding the back layer side of the decorative film to the base material and pasting it. As a method of sticking the decorative film to the base material, for example, a method of heating the decorative film and sticking it to the base material is mentioned. For example, thermoforming, vacuum forming, pressure forming, vacuum-pressure forming, packaging, etc. are mentioned. As a specific example of vacuum forming, the following method can be enumerated: using a three-dimensional surface decoration (Three dimension Overlay, TOM) forming machine (manufactured by Busch Vacuum Co., Ltd., model: NGF-0406) as a vacuum-compression forming machine, heating in the heater At a temperature of 80° C. to 140° C., paste the decorative film on the base material. As a specific example of the packaging, there may be mentioned a method of adhering the decorative film along the substrate while heating it with a dryer to soften it.

When using the decorative laminated structure of the present invention, a light source such as a light emitting diode (light emitting diode, LED) backlight can be arranged inside or on the back side of the base material for use. A light-emitting unit that makes the exterior design stand out for visual recognition. Fig. 6 is a schematic cross-sectional view showing an example of a light emitting unit using the decorative laminated structure shown in Fig. 5 . As shown in FIG. 6 , the light emitting unit 400 preferably has a light source 210 inside or on the rear side of the substrate 200 included in the decorative laminated structure 300 of the present invention.

By arranging a light source inside or on the rear side (the side opposite to the decorative film) of the base material and using the decorative laminated structure of the present invention, a light-emitting unit can be constituted. In this case, it is preferable that at least a part of the translucent region overlaps with the light source. Although it does not specifically limit as said light source, For example, a light emitting diode (LED) is mentioned. In the light-emitting unit including the decorative laminated structure of the present invention, the design cannot be easily recognized when the light source is turned off, while the design can be clearly recognized when the light source is turned on.

Fig. 7 is a schematic front view of the light emitting unit shown in Fig. 6 viewed from the front surface side when the light source is turned off. In addition, the light shielding layer 120 is provided in the form shown in FIG. 1 and FIG. 2 . As shown in FIG. 7 , when the light source is turned off, the design cannot be visually recognized and cannot be distinguished from the surrounding decorative film. Since the light-shielding layer 120 is disposed on the rear side of the semi-transmissive film 20 , the semi-transmissive film 20 covers the thickness of the light-shielding layer 120 , so that it is difficult to visually recognize the design when the light source is turned off.

8 is a schematic front view of the same light-emitting unit as that shown in FIG. 6 viewed from the front surface side when the light source is turned on. The transparent area 1 overlaps with the light source 210 . Therefore, as shown in FIG. 8 , when the light source is turned on, the light emitted from the light source 210 and incident on the decorative film is transmitted through the light-transmitting region 1 and emitted toward the observer, so that the design (star in FIG. 8 ) can be visually recognized. shape design).

[Example]

Hereinafter, although an Example is given and this invention is demonstrated in more detail, this invention is not limited only to these Examples.

Materials used in Examples and Comparative Examples are shown in Table 1 below.

[Table 1]

BN3009 shown in Table 1 is a masterbatch of a black colorant containing carbon black. BN3007 is a blue colorant masterbatch containing copper phthalocyanine blue and magnesium carbonate. BN3035 is a masterbatch of pearlescent tone colorants containing mica and stannous oxide. Rezaroid LU-504SP is a matte coating agent containing polyurethane resin and silica. SEIKABOND C-83 is a hardener containing polyisocyanate. ARONTAC MPT-29 is an ethyl acetate solution of acrylic copolymer. Poriment NK-380 is a graft compound of methacrylic acid-methyl methacrylate copolymer and polyethyleneimine.

"Making of Decorative Film"

(Example 1)

In Example 1, as shown in FIG. 4, a damage-resistant coating 70, a top film 60, a semi-transmissive film 20, a light-shielding layer 120, a base film 30, a bottom layer 50, and an adhesive layer 40 are produced in order from the front surface side. Furthermore, a decorative film with a spacer (not shown) is added to the back side.

<Preparation of base film and top film>

The vinyl chloride resin (PVC) film used as the base film 30 and the top film 60 was produced in the following procedure. With respect to 100 parts by weight of the vinyl chloride resin shown in Table 1, add 25.0 parts by weight of di-undecyl phthalate (DUP) as a plasticizer, and melt it using a Banbury mixer. After kneading, it was formed into a sheet with a thickness of 90 μm by an inverted L-shaped calender to produce a PVC film. The total light transmittance of the PVC film is 88%. Similarly, a PVC film with a thickness of 70 μm used as a base film was also produced.

<Formation of light-shielding layer>

On the surface of the base film 30 , the light-shielding layer 120 is partially formed by performing gravure printing a plurality of times using a solvent-based black gravure printing ink. The printed part becomes the light-shielding region 2 , and the unprinted part becomes the light-transmitting region 1 . The optical density D ₁ of the portion of the base film 30 on which the light-shielding layer was printed was measured using a desktop transmission densitometer 361T (manufactured by X-Rite Corporation), and the results are shown in Table 2 below. In addition, the optical density _D1 is made into the average value of the optical density measured about arbitrary 3 points (the measurement field of view of 1 point is 1 mmφ).

<Production of semi-transmissive film>

25 parts by weight of DUP as a plasticizer was added to 100 parts by weight of PVC shown in Table 1, and 2.1 parts by weight of a black colorant, 0.07 parts by weight of a blue colorant, and 0.07 parts by weight of a pearl tone colorant were added to 100 parts by weight of PVC. 1.05 parts by weight, melted and kneaded with a Banbury mixer, and then formed into a sheet with a thickness of 80 μm by an inverted L-shaped calender to produce a semi-transmissive film 20 . The optical density D ₂ of the single layer of the semi-transmissive film 20 was measured using a table-top transmission densitometer 361T (manufactured by X-Rite Corporation), and the results are shown in Table 2 below. In addition, the optical density _D2 is made into the average value of the optical density measured about arbitrary 3 points (the measurement field of view of 1 point is 1 mmφ).

<Preparation of damage-resistant coating>

A coating agent was applied to the surface of the top film 60 and dried to form a scratch-resistant coating layer 70 with a thickness of 2 μm. Embossing is performed on the surface on the side where the damage-resistant coating layer 70 is formed to form a plain weave-like pattern.

<Lamination of film, and preparation of adhesive layer and base layer>

The surface of the base film 30 on which the light-shielding layer 120 is provided is thermally laminated to one of the surfaces of the semi-transmissive film 20, and the surface of the top film 60 opposite to the surface on which the scratch-resistant coating is formed is bonded to The other side of the semi-transmissive film is thermally laminated in contact with each other to obtain a laminated film in which the anti-scratch coating 70 , the top film 60 , the semi-transmissive film 20 , the light-shielding layer 120 , and the base film 30 are sequentially laminated.

Using a polyethylene terephthalate film with a thickness of 50 μm as a spacer, 240 g/m of an adhesive and a crosslinking agent were applied to form an adhesive layer with a dry thickness of 40 μm. A primer agent was applied to the surface of the base film 30 of the laminated film to form a base layer, and the laminated film and the adhesive layer were laminated through the base layer to produce the decorative film of Example 1.

(Example 2, Comparative Example 1 to Comparative Example 4)

As shown in Table 2 below, the optical density D ₂ of the semi-transmissive film was changed by adjusting the content of the black colorant (BN3009), and the optical density D ₁ of the part printed with the light-shielding layer was changed. The decorative films of Example 2 and Comparative Examples 1 to 4 were produced in the same manner. In Table 2, the content of the plasticizer and the content of BN3009 are content (parts by weight) with respect to 100 parts by weight of the resin component. The optical density _D1 of the portion where the light-shielding layer is printed is changed by adjusting the number of gravure printings printed on the surface of the base film 30 .

(Example 3)

Except having changed the kind of plasticizer to diisononyl phthalate (DINP), it carried out similarly to Example 1, and produced the decorative film of Example 3.

(Example 4)

Except having changed the kind of plasticizer to diisononyl phthalate (DINP), it carried out similarly to Example 2, and produced the decorative film of Example 4.

(Example 5)

The decorative film of Example 5 was produced in the same manner as in Example 2 except that both the thickness of the semi-transmissive film and the thickness of the base film were changed to 70 μm.

(Example 6)

Both the thickness of the semi-transmissive film and the thickness of the base film were changed to 70 μm, and as shown in Table 2 below, the optical density D ₂ of the semi-transmissive film was changed by adjusting the content of the black colorant, and the part where the light-shielding layer was printed was changed. The decorative film of Example 6 was produced in the same manner as in Example 1 except that the optical density D ₁ was obtained. The optical density _D1 of the portion where the light-shielding layer is printed is changed by adjusting the number of gravure printings printed on the surface of the base film 30 .

"Fabrication of Decorative Laminated Structures and Light-Emitting Units"

The spacers were removed from the decorative films of Examples and Comparative Examples, the adhesive layer was brought into contact with the surface of the base material, and the decorative laminated structure was produced by vacuum forming at a set temperature of 120°C. As the base material, a car interior member made of transparent resin is used. Furthermore, an LED backlight mounted with a full-color LED light guide plate (thickness: 3 mm) was installed on the back side of the substrate to obtain a light-emitting unit. In addition, the thickness of the base material at the portion where the LED backlight is disposed is about 3 mm.

"Evaluation Test"

For the obtained light-emitting unit, the following methods were used to evaluate (1) light leakage when the light source was turned on, (2) concealment of the design when the light source was turned off, and (3) visibility of the design when the light source was turned on. This evaluates the performance of the decorative film. The results are described in Table 2 below.

(1) Light leakage when the light source is turned on

When the light source was turned on, the light-emitting unit was visually observed from the front side, and the case where light was visually recognized only in the light-transmitting region was marked as ○, and the case where light leakage was observed in parts other than the light-transmitting region was regarded as ×.

(2) Concealment of the appearance design when the light source is extinguished

When the light source was turned off, the light-emitting unit was visually observed from the front side, and the pattern (design) formed by the light-shielding region and the light-transmitting region was not visually recognized as ○, and the case was visually recognized as ×.

(3) Visibility of the design when the light source is turned on

When the light-emitting unit is visually observed from the front side while the light source is turned on, the case where a clear design with a contrast that appears to be bright in the light-transmitting region can be visually recognized is set to ○, and the case where the design is not visually recognized, or although substantially A case where it was visually recognized but the contrast was low was set to x.

[Table 2]

As shown in Table 2, for the decorative films of Examples 1 to 6, no light leakage was observed when the light source was turned on, and the concealment of the design when the light source was turned off and the visibility of the design when the light source was turned on were good. On the other hand, in Comparative Examples 1 to 3, since the optical density of the light-shielding region was low and the light-shielding property was insufficient, light leakage was observed when the light source was turned on. In addition, in Comparative Examples 1 to 3, since the optical density of the front surface layer was insufficient, the design was not hidden when the light source was turned off, and the visibility of the design was not good when the light source was turned on. In Comparative Example 4, since the optical density of the front surface layer was too high, the design was hidden when the light source was turned off, but the design visibility was poor when the light source was turned on. In addition, since the optical densities of the damage-resistant coating, the top film, the bottom layer and the adhesive layer in the examples are all very small, it can be considered that the optical density of the light-shielding area is approximately D ₁ +D ₂ , and the optical density of the front surface layer is approximately at D ₁ .

Claims (3)

1. A decorative film is characterized in that,

has a front surface layer and a light shielding layer,

the light shielding layer is partially provided on the back side of the front surface layer,

the decorative film has a light-shielding region having the light-shielding layer and having an optical density of 5.3 or more, and a light-transmitting region having no light-shielding layer,

the front surface layer has an optical density of 0.8 or more and 1.5 or less.

2. A decorative film is characterized in that,

has a front surface layer, a light shielding layer, and a back surface layer,

the light shielding layer is partially disposed between the front surface layer and the back surface layer,

the decorative film has a light-shielding region having the light-shielding layer and having an optical density of 5.3 or more, and a light-transmitting region having no light-shielding layer,

the front surface layer has an optical density of 0.8 or more and 1.5 or less.

3. A decorative laminated structure is characterized in that,

the decorative film according to claim 1 or 2 is laminated and integrated on a base material, and the base material is disposed on the back surface side of the decorative film.

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