JP2013132827A - Transfer film and substrate film for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily form on a film surface a fine rugged shape such as hair line.SOLUTION: The transfer film 100 includes: a substrate film 1 on the surface of which a predetermined concave pattern 6 is formed; a separation layer 2 provided to the lower layer of the substrate film 1; a decorative printing layer 3 formed on the lower layer of the separation layer 2 by inkjet printing or the like; and an adhesive layer 4 provided to the lower layer of the decorative printing layer 3. With a transfer layer 5 formed of the separation layer 2 and the decorative printing layer 3 being temporarily cured, the transfer film 100 is adhered on the curved surface of a product. The transfer layer 5 in the temporarily curing condition is highly elastic to follow the surface of the substrate film 1 into deformation, allowing the transfer film 100 to be surely adhered on the product surface. When the substrate film 1 is separated, a convex pattern 7 corresponding to the concave pattern 6 is formed on the surface of the separation layer 2. Thereby a fine rugged shape can be easily formed on the surface of the product S, with enhanced decoration property.

Description

  The present invention relates to a transfer film and a base film for transferring a film onto a product surface for decoration.

  Conventionally, an IMD (In-Mold Decoration) technique for decorating a material by attaching a printed film is known. FIG. 6 is an explanatory diagram showing a decoration method by IMD disclosed in Patent Document 1. In FIG. In this decoration method, a decorative print layer 502 using an ultraviolet curable ink is laminated on a transparent synthetic resin film 501, and a white pressing layer 503 and a binder layer 504 are further laminated. Then, the transfer film 500 is thermocompression bonded to the surface of the resin molded body as the product S through the binder layer 504.

JP 2008-272946 A

In recent years, there has been a demand for further decorating properties for products decorated with IMD technology, and for example, decorating that forms irregularities on the surface of a film has been proposed. However, when unevenness is formed on the surface of the film by ink jet printing, there is a problem that it is extremely difficult to form fine unevenness such as a hairline.

Accordingly, an object of the present invention is to make it possible to easily form fine irregularities on the film surface.

  The transfer film according to the first invention is a transfer film provided with a transfer layer for decorating the product surface on the surface of the base film, wherein the base film is along the interface with the transfer layer. It has a releasable releasability and is formed of a resin having ruggedness in the thickness direction formed on its surface and having extensibility.

When the transfer film is attached to the surface of the product and the base film is peeled from the transfer layer along the interface, the unevenness corresponding to the unevenness of the base film is transferred to the surface of the transfer layer. Thereby, uneven | corrugated shaped decoration can be easily given to the product surface. Moreover, since the base film has extensibility, even if it is a product having a curved surface, the transfer film can be reliably attached and easily peeled off, so that a beautiful decoration can be achieved. Moreover, since the said base film can be reused even after the transfer peeling to a curved surface, for example, an expensive base film having a micro uneven shape such as a hairline can be effectively used. The transfer layer may be composed of a combination of a release layer that also serves as a hard coat layer and a decorative printing layer by inkjet, or may be composed of only a colorless or colored release layer, or by inkjet. You may be comprised only from a decoration printing layer. In addition, the base film is formed of a material that has high releasability with respect to an ultraviolet curable resin or a thermosetting resin, or is subjected to surface modification that can improve releasability.

The transfer film according to a second invention is the transfer film according to the first invention, wherein the transfer layer further comprises a release layer that can be peeled along an interface with the base film, and a layer provided below the release layer. It is characterized by comprising a decorative layer.

  By providing the release layer, the base film can be cleanly peeled at the interface between the base film and the release layer. For this reason, the uneven | corrugated shape of a base film is transferred neatly as expected. Moreover, the decoration layer under the peeling layer can be seen through the peeling layer. For this reason, the decorating property of a product improves more.

The transfer film according to a third invention is characterized in that, in the first or second invention, the transfer layer is in a temporarily cured state.

  Since the temporarily cured resin has higher extensibility than the main cured state, as a result, the extensibility of the entire transfer film is improved. If the transfer film is affixed to the surface of the product before the transfer layer is fully cured, the transfer film is flexibly deformed and reliably affixed even if the product has a curved surface. After pasting, after the transfer layer is fully cured, the substrate film is peeled off, thereby realizing a beautiful decoration with irregular shapes.

The transfer film according to a fourth invention is characterized in that, in any one of the first to third inventions, the base film is made of an olefin resin.

  That is, high releasability can be obtained by forming the base film itself from an olefin resin. For this reason, the peelability from the transfer layer is enhanced, and the uneven shape of the substrate film is transferred cleanly as expected.

The base film of the transfer film according to the fifth invention is a base film that forms a transfer layer that decorates the product surface, and the base film can be peeled along the interface with the transfer layer. It has a good mold release property and has unevenness in the thickness direction formed on the surface thereof.

  According to this invention, by forming the unevenness of the base film on the transfer layer, it is possible to give a high decorative property to the surface of the product, and for example, a fine uneven shape such as a hairline can be efficiently formed. become.

It is sectional drawing which shows the structure of the film for transfer which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows the example of sticking to the curved surface of the film for transfer. It is explanatory drawing which shows an example of the manufacturing method of a base film. It is explanatory drawing which shows another example of the manufacturing method of a base film. It is explanatory drawing which shows another example of the manufacturing method of a base film. It is explanatory drawing which shows an example of the decorating method by the conventional IMD.

(Embodiment 1)
FIG. 1 is a cross-sectional view showing the structure of a transfer film according to Embodiment 1 of the present invention, where (a) shows a state before peeling of the base film, and (b) shows the transfer film on the surface of the product S. The state which affixed and the base film 1 was peeled is shown. The transfer film 100 includes a base film 1 having a predetermined concave pattern 6 formed on the surface, a release layer 2 that also serves as a hard coat layer (protective layer) provided under the base film 1, and a release layer. The decorative printing layer 3 formed by inkjet printing or the like on the lower layer of 2 and the adhesive layer 4 provided on the lower layer of the decorative printing layer 3. In the product S, the release layer 2 and the decorative print layer 3 are attached via the adhesive layer 4 to form a convex pattern 7 to which the concave pattern 6 of the base film 1 is transferred. The release layer 2 and the decorative print layer 3 are referred to as a transfer layer 5.

The base film 1 is made of an olefin-based resin having high peelability (details will be described later), and the concave pattern 6 on the surface thereof is formed in the thickness direction of the base film 1. The concave pattern 6 includes a V-shaped cross section, an inverted trapezoid, and the like. In addition, although parts other than the concave pattern 6 on the surface of the base film 1 can be considered as the convex pattern 7, the concave and convex shape on the surface of the base film 1 will be described as the concave pattern 6 below for convenience.

  For the release layer 2, a transparent ultraviolet curable (UV curable) resin material is used. In particular, when the hard coat layer is also used, an acrylate resin is used. Specifically, it is preferable to use a polymer acrylate as the main component. The polymer acrylate can be temporarily cured by heating at 70 ° C. for 5 minutes with a dryer, and the tensile elongation (JIS K7127) at that time is about 50%. In addition, you may make it harden | cure by natural drying. The hardness at the time of temporary curing is about F in pencil hardness (JIS K 5600-5-4 paint general test method, mechanical properties of coating film, scratch hardness (pencil method)). That is, the polymer type acrylate has high peelability with respect to the base film 1 because the pencil hardness is about F in the temporarily cured state, and the tensile elongation is also high, so that the extensibility of the transfer film 100 or Extensibility can be increased.

The main curing of the release layer 2 with ultraviolet rays is performed with a high-pressure mercury lamp (80 W / cm) under an energy condition of 500 mJ / cm ² . The main wavelength of the high-pressure mercury lamp is 365 nm, and the wavelength components of 254 nm, 313 nm, 405 nm, and 436 nm are strong, which is suitable for curing the release layer 2 made of polymer type acrylate.

As another material of the release layer 2, urethane acrylate can be used. Examples of other acrylate resins include urethane methacrylate, bisphenol A, bisphenol F, bisphenol AD, water-added bisphenol A, dimer acid-modified epoxy acrylate or epoxy methacrylate, polyester, and the like. It is also possible to use a system acrylate, a polyester system methacrylate, a silicone system acrylate, a silicone system methacrylate, an alkyd system acrylate, an alkyd system methacrylate, or the like.

  The release layer 2 is formed by a coater, gravure printing, screen printing, ink jet, or the like. The thickness of the release layer 2 is about 10 μm to 50 μm in the state including the binder, and 5 μm to 15 μm in the state after drying.

In the above description, the release layer 2 is temporarily cured. However, depending on the viscosity and material of the release layer 2, high extensibility can be maintained without being temporarily cured. In such a case, the temporary curing step can be omitted, and the material of the release layer 2 can be used as the release layer 2 before curing while being printed or applied. Furthermore, if the decorative printing layer 3 is laminated and formed on the peeling layer 2, the peeling layer 2 is held between the base film 1 and the decorative printing layer 3, so that the transfer can be performed without temporary curing. Easy to handle film.

  The decorative print layer 3 includes a print drawing layer drawn by inkjet using ultraviolet curable ink, and a white pressing layer obtained by inkjet printing white toner that increases the saturation of the print drawing layer. By using an ink mainly composed of isobornyl acrylate (about 50% by weight), tetrahydrofurfuryl acrylate (about 20% by weight) modified amine acrylate oligomer (about 10 to 25% by weight), Tensile elongation can be obtained. The thickness of the decorative print layer 3 is preferably 5 to 40 μm, and more preferably 20 to 30 μm. Note that the decorative printing layer 3 may be formed using a screen printing method, a gravure printing method, a pad printing method, an offset printing method, a thermal transfer printing method, or the like, in addition to an inkjet. Note that the white pressing layer can be omitted depending on the contents of the print design. The white pressing layer may be formed by screen printing or may be formed by laminating a white resin layer.

  The ink is cured by irradiating the LED with ultraviolet rays with low energy. Ultraviolet irradiation is performed at the time of printing with an ink jet printer, for example. In the cured state, the tensile elongation of the ink is about 100%. Depending on the material and viscosity used for the decorative printing layer 3, it may not be cured at this time, and may be cured by being irradiated with ultraviolet rays under the above conditions after being attached to the product S.

For the adhesive layer 4, for example, a material whose main component is cyclohexanone is used. In addition, resins such as acrylic resin, vinyl chloride resin, vinyl acetate resin, polyester resin, and polyamide resin can be used. The thickness of the adhesive layer 4 varies depending on the type of resin of the product S to be attached, but is generally about 5 to 30 μm.

  As shown in FIG. 1B, the transfer film 100 is attached to the surface of the product S via the adhesive layer 4, and then the base film 1 is peeled off from the release layer 2, and the transfer layer 5 is removed. The surface of the product S is decorated by curing. Since the convex layer 7 corresponding to the concave pattern 6 of the base film 1 is formed on the release layer 2, the decoration having the desired convex pattern 7 on the surface of the product S by peeling the base film 1. It can be performed. The convex pattern 7 is, for example, a fine line.

Affixing to the product S is performed by, for example, an IML (In-Mold Lamination) technique. In the IML, the transfer film 100 is placed in a predetermined mold, and the transfer film 100 is attached to the surface of the product S with the mold closed. In addition to the IML, a roll type or up-down type thermal transfer, vacuum press transfer, or the like may be used for attaching the transfer film 100.

  In particular, when the transfer film 100 according to the present invention is attached to the curved portion (or corner portion) of the product S, the base film 1 itself has extensibility and the transfer layer 5 is highly stretched in a temporarily cured state. Therefore, the transfer film 100 has high flexibility as a whole. In other words, since the transfer layer 5 has higher extensibility than the base film 1, it becomes easy to follow the deformation and elongation of the base film 1. Therefore, as shown in FIG. The transfer film 100 can be attached without difficulty along (or the corner).

Then, as shown in FIG. 2 (b), after peeling off the base film 1, the transfer layer 5 is irradiated with ultraviolet rays having a specific wavelength to be fully cured. The release layer 2 functions as a hard coat layer by the main curing. An LED, a mercury lamp, a metal halide lamp, or the like is used for ultraviolet irradiation. Ink curing requires UV irradiation around 380 nm, which is the dominant wavelength of the LED lamp, and curing of the release layer 2 requires UV irradiation with a high-pressure mercury lamp. For this reason, it is preferable to irradiate ultraviolet rays simultaneously with the LED lamp and the high-pressure mercury lamp.

  Moreover, since the base film 1 has extensibility, the peelability from the peeling layer 2 is good, and it can be reused even after peeling. When the substrate film 1 is reused, it is preferable to remove attached dust, components of the release layer 2 and the like with a cleaner or the like. Moreover, since the base film 1 has high extensibility, even if deformation is applied on a curved surface or the like, the base film 1 is peeled off while being stretched, so that the release layer 2 is not broken. This is particularly useful in the case of fine irregularities such as hairlines. Further, when the base film 1 is peeled before the release layer 2 is fully cured, it is useful from the viewpoint of preventing damage to the release layer 2 that the base film 1 itself has extensibility.

  Note that the release layer 2 may be fully cured before the base film 1 is peeled off. Since the base film 1 is made of PE and PP and has a thickness of about 50 μm to 150 μm, the base film 1 can sufficiently transmit the ultraviolet light, so that the base film 1 can be irradiated with the ultraviolet light.

(Manufacturing method of the base film 1)
FIG. 3 is an explanatory view showing an example of a method for producing the base film 1. First, as shown to Fig.3 (a), the convex pattern 52 to form on the surface of the peeling layer 2 is formed in the surface of the metal roller 51 with a hairline processing machine.

  Subsequently, as shown in FIG. 3B, the material 54 of the base film 1 is applied on the table 53 with high flatness. The base film 1 is made of an olefin resin having high releasability. For example, polypropylene resin (PP resin), polyethylene resin (PE resin), ethylene vinyl acetate copolymer resin (EVA resin), polyolefin soft resin (TPO resin), polyethylene terephthalate resin (PET resin), polycarbonate resin (PC resin) Etc. Among these olefin-based resins, it has been found that a polypropylene resin (PP resin) and a polyethylene resin (PE resin) have the most preferable releasability as the base film 1 based on the trial research by the inventors. In addition, 50-250 micrometers is preferable and the thickness of the said base film 1 has more preferable 100-180 micrometers.

  Next, as shown in FIG. 3C, the roller 51 is rolled on the material 54 of the base film 1 coated on the table 53, and the convex pattern 52 on the roller surface is used as the concave pattern 6 of the base film 1. Transcript. Thereby, as shown in FIG.3 (d), the predetermined concave pattern 6 is formed in the surface of the base film 1. FIG. Subsequently, the base film 1 on which the concave pattern 6 is formed is crosslinked to complete the base film 1 having the predetermined concave pattern 6 as shown in FIG.

  As shown in FIG. 4, a release layer 61 may be formed on the surface of the base film 1. In particular, it is effective when a polyethylene terephthalate resin (PET resin) or a polycarbonate resin (PC resin) having a slightly inferior moldability is used. When another material having releasability is laminated, the concave pattern 6 is buried, so that the release layer 61 is preferably provided as a surface modification layer by a laser or the like.

  Since the transfer layer 5 has high extensibility of about 1.5 to 2.0 times in the plane direction before the main curing, the elongation of the entire transfer film depends on the elongation of the base film 1. Become. As above-mentioned, since the base film 1 is a material with suitable PP resin or PE resin, and the thickness is about 140 micrometers, it can anticipate the tensile elongation of 20-30%. For this reason, since the high extensibility is obtained as the whole transfer film, it can be naturally attached to the curved surface or corner portion of the product S.

  According to the transfer film 100 described above, since the convex pattern 7 is formed on the surface of the release layer 2 along the concave pattern 6 of the base film 1, the fine convex pattern 7 can be expressed easily. Thereby, a high level of decoration can be performed on the surface of the product S. In addition, since the transfer film 100 has high extensibility, it can be naturally attached to a curved portion or a corner portion of the product S. Moreover, since the base film 1 can be reused, the production efficiency of the transfer film 100 is improved.

  Further, as shown in FIG. 5, the decorative print layer 3 may be omitted, and the transfer layer 62 may be formed by coloring the release layer 2. Thereby, the decoration by coloring and the convex pattern 7 on the surface of the peeling layer 2 is attained. As the colorant in this case, a metallic pigment made of a scale-like foil powder of a metal, an alloy, or a metal compound such as aluminum, chromium, nickel, tin, titanium, iron phosphide, copper, gold, silver, or brass, mica-like Pearlescent pigment made of foil powder such as iron oxide, titanium dioxide coated mica, titanium dioxide coated bismuth oxychloride, bismuth oxychloride, titanium dioxide coated talc, fish scale foil, colored titanium dioxide coated mica, basic lead carbonate, Fluorescent pigments such as strontium aluminate, calcium aluminate, barium aluminate, zinc sulfide, calcium sulfide, white inorganic pigments such as titanium dioxide, zinc white, antimony trioxide, zinc white, petal, vermilion, ultramarine blue, cobalt blue, Inorganic pigments such as titanium yellow, yellow lead, carbon black, isoindolinone yellow, Hansa Yellow A Quinacridone red, it Permanent Red 4R, phthalocyanine blue, be mixed Indanthrene Blue RS, (including dyes) organic pigments such as aniline black 1 or 2 or more.

100 Transfer Film 1 Base Film 2 Peeling Layer 3 Decorative Print Layer 4 Adhesive Layer 5 Transfer Layer 6 Concave Pattern 7 Convex Pattern S Product

Claims (5)

A transfer film provided with a transfer layer for decorating the product surface on the surface of the base film,
The base film has a releasability that can be peeled along the interface with the transfer layer, and has a surface formed with unevenness in the thickness direction, and is made of a resin having extensibility. Transfer film. Furthermore, the said transfer layer consists of a peeling layer which can be peeled along the interface with the said base film, and the decoration layer provided in the lower layer of the said peeling layer, The transfer of Claim 1 characterized by the above-mentioned. Film.   The transfer film according to claim 1, wherein the transfer layer is in a temporarily cured state.   Furthermore, the said base film consists of olefin resin, The film for transfer as described in any one of Claims 1-3 characterized by the above-mentioned. A base film for forming a transfer layer for decorating the product surface,
A base film for a transfer film, wherein the base film has a releasability capable of being peeled along an interface with the transfer layer, and unevenness in a thickness direction is formed on the surface thereof.

Images