TWI774073B - Transfer film and its use - Google Patents

Abstract

The invention provides a transfer film and use thereof. The transfer film includes a substrate and a high-gloss layer, the substrate has a bonding surface, the high-gloss layer has an opposite mirror surface and a bonding surface, and the high-gloss layer has The mirror surface is in direct contact with the bonding surface of the substrate. Using the transfer film of the present invention to transfer onto the target object can smoothly modify the surface of the target object, so that the overall appearance of the target object presents the visual effect of mirror reflection, thereby enhancing the texture, detail and value of the overall appearance of the target object.

Description

Transfer film and its use

The present invention relates to a transfer film, especially a transfer film capable of producing mirror reflection effects; the present invention also relates to the use of a transfer film, especially the use of a variety of objects of different materials.

With the improvement of living standards, people not only pursue the inner quality of products, but also pay more attention to the appearance of products to show their personal taste and uniqueness. Among them, in order to properly display the texture of the product, it is a common practice to improve the gloss or brightness of the product by coating, which has led to the development of mirror decoration technology.

The current mirror decoration technology includes water electroplating, vacuum electroplating, water transfer printing and spraying. However, water electroplating will generate a large amount of metal waste liquid, which is easy to cause environmental problems; vacuum electroplating equipment is relatively expensive, and the process is complex and high cost; water transfer printing is prone to film rupture and a large amount of waste water pollution; There are many restrictions, except that the object itself needs to have a high degree of flatness so that the sprayed particles can show a mirror effect after stacking, and it is necessary to spray multiple layers of paint on the object to improve the flatness before it can show the mirror reflection effect, so spraying is used to achieve The effect of mirror decoration also has the problem of high cost.

Based on the shortcomings of previous water electroplating, vacuum electroplating, water transfer printing and spraying, the prior art turned to develop a transfer film, the transfer film from bottom to top sequentially includes a substrate, a mirror-like release layer and a high-gloss layer. By setting the mirror-like release layer between the substrate and the high-gloss layer, it is ensured that after the user applies the transfer film to the object to be transferred, the high-gloss layer can be attached to the surface of the object, and The high-gloss layer is smoothly separated from the mirror-like release layer and the substrate, so that the high-gloss layer is transferred to the surface of the target object, in order to show the mirror reflection effect.

However, when trying to decorate the surface of the target object through the transfer film in the prior art, it was found that although the provision of a mirror-like release layer helps the high-gloss layer to fall off the substrate and transfer to the surface of the target object, the mirror-like release layer The layer has a certain thickness, it is not easy to adhere to the surface of the decorative object during heating, stretching and pressure molding, and it will inevitably produce ripples or orange peel. The above factors all lead to the imitation mirror surface transferred on the object. The release layer and the highlight layer cannot exhibit the expected specular reflection effect, so it is necessary to improve.

In order to overcome the shortcomings of the prior art, the purpose of the present invention is to provide a transfer film and its use, which can omit the use of the imitation mirror surface release layer, so that the transfer film can be transferred to the surface of the target object smoothly. The target object has the effect of specular reflection.

In order to achieve the above object, the present invention provides a transfer film, comprising: a substrate and a high-gloss layer disposed on the substrate, the substrate has a bonding surface, the high-gloss layer has an opposite mirror surface and a bonding The mirror surface of the high-gloss layer is in direct contact with the bonding surface of the substrate, wherein the arithmetic mean roughness of the bonding surface of the substrate is less than 1.5 microns, the material of the substrate comprises a polyethylene composition, and the polyethylene The composition has a hydroxyl group (-OH group), and the material of the high-gloss layer comprises polymethyl methacrylate.

By means of the front-release technology, the transfer film of this creation can save the need to set up a mirror-like release layer in order to facilitate its separation from the substrate, and has the expected mirror reflection effect. In other words, the highlight layer of this creation can not only be well attached to the surface of the target object after transfer, but also give the target object a specular reflection effect.

The mirror surface and the bonding surface of the above-mentioned high-gloss layer are made of the same material, and both have high-gloss characteristics and can exhibit a mirror reflection effect, but the bonding surface is used for further bonding to a target object.

In this specification, "the mirror surface of the high-gloss layer is in direct contact with the bonding surface of the substrate" means that in the transfer film, there is no additional mirror-like release as in the prior art between the high-gloss layer and the substrate. Floor.

Preferably, the arithmetic mean roughness of the joint surface of the substrate is less than 1.2 microns; more preferably, the arithmetic mean roughness of the joint surface of the substrate is less than 1 micron; The arithmetic mean roughness is less than or equal to 0.8 microns. In one embodiment, the arithmetic mean roughness of the bonding surfaces of the substrates is greater than or equal to 0.05 microns and less than or equal to 0.2 microns. By controlling the arithmetic mean roughness of the joint surface of the substrate, the present invention maintains the surface characteristics of the mirror surface of the high-gloss layer when the mirror surface of the high-gloss layer is in direct contact with the joint surface of the substrate.

Preferably, the longitudinal (MD) elongation at break of the substrate is 300% to 600%, and the transverse (TD) elongation at break of the substrate is 300% to 600%. More preferably, the longitudinal elongation at break of the substrate is 375% to 525%, and the transverse elongation at break of the substrate is 375% to 525%. Even more preferably, the longitudinal elongation at break of the substrate is 400% to 500%, and the transverse elongation at break of the substrate is 400% to 500%. According to this, the transfer film can not only be applied to a flat surface with a large area, but also applied to an object with different detailed structures or a concave-convex surface.

其中，n1為大於或等於0以及小於5000的自然數，以及n2為大於0和小於5000的自然數。 Preferably, the polyethylene-based composition in the material of the above-mentioned substrate can be modified polyethylene, which has a plurality of hydroxyl groups, and the modified polyethylene can comprise the following formula I and/or formula II. Repeat unit:

Wherein, n1 is a natural number greater than or equal to 0 and less than 5000, and n2 is a natural number greater than 0 and less than 5000.

When n1 is 0, it means that the polyethylene-based composition in the material of the substrate only contains the repeating unit of formula II, that is, the repeating unit of the polyethylene-based composition is composed of formula II.

Preferably, n1 is a natural number from 0 to 3000.

Preferably, n2 is a natural number from 1000 to 4000.

Preferably, the degree of polymerization of the polyethylene-based composition is 2,000 to 3,000. More preferably, the polymerization degree of the polyethylene-based composition is 2300-2600.

The material of the above-mentioned base material may further comprise a plasticizer, and based on the total weight of the material of the base material, the content of the plasticizer is 8 to 13 weight percent. Preferably, based on the total weight of the base material, the content of the plasticizer is 9 to 12 weight percent.

In this specification, the high-gloss layer has the characteristics of high gloss, and after the high-gloss layer of the transfer film is transferred to the target object, the surface of the target object exhibits a specular reflection effect visible to the naked eye. The glossiness of the mirror surface of the high-gloss layer is greater than or equal to 80GU. In one embodiment, the reading value of the mirror surface of the high-gloss layer measured by a 60-degree gloss meter is greater than or equal to 90GU to 100GU. In another embodiment, the reading value of the specular surface of the high-gloss layer measured by a 20-degree gloss meter is greater than or equal to 85GU to 95GU. In another embodiment, the reading value of the specular surface of the high-gloss layer measured by an 80-degree gloss meter is greater than or equal to 95GU to 105GU.

Preferably, the above-mentioned poly(methyl methacrylate) (PMMA for short) is a polymethyl methacrylate oligomer (PMMA oligomer).

Preferably, the material for making the high-gloss layer can include solvents such as Methyl Ethyl Ketone (MEK), n-butyl acetate (BAC), ethyl acetate (EAC), and the like. For example, 1-hydroxy-cyclohexyl-phenyl ketone (1-hydroxycyclohexyl phenyl ketone, trade name: TBO184) is the starting agent, but it is not limited to this. This creation uses methyl ethyl ketone as a solvent, which facilitates the uniform distribution of polymethyl methacrylate and enables the application of a high-gloss layer to the substrate.

The above-mentioned materials for making the high-gloss layer can also be added with a cross-linking agent or UV curing glue (such as: UV-curable resin such as urethane acrylic resin or modified epoxy acrylic resin), so that the high-gloss layer can be hardened and fixed after being irradiated with ultraviolet rays. It can be applied to objects made of materials such as plastic and metal, without the need for a separate adhesive layer to combine the object and the high-gloss layer. In one embodiment, the energy range of ultraviolet irradiation may be 500mJ/cm ² to 1800mJ/cm ² ; in another embodiment, the energy range of ultraviolet radiation may be 500mJ/cm ² to 1500mJ/cm ² .

The thickness of the above-mentioned substrate may be 30 micrometers to 100 micrometers; preferably, the thickness of the substrate may be 20 micrometers to 100 micrometers.

The thickness of the high-gloss layer may be 10-100 microns; preferably, the thickness of the high-gloss layer may be 10-50 microns; more preferably, the thickness of the high-gloss layer may be 15-50 microns. The present invention can improve the brightness and specular reflection effect of the highlight layer by increasing the thickness of the highlight layer.

The present invention further provides the use of a transfer film, which comprises applying the above transfer film to a target. Accordingly, after the transfer film is transferred to the target object, the appearance of the target object can be given the visual effect of mirror reflection through the highlight layer of the transfer film.

Specifically, after the transfer film is applied to the surface of a target, the bonding surface of the high-gloss layer of the transfer film is adhered to the surface of the target, and the substrate of the transfer film can be self-glossy The mirror surface of the layer is peeled off.

In one embodiment, after the high-gloss layer of the transfer film contacts the surface of the target, the transfer film can be heated at a temperature of 50°C to 120°C to soften the high-gloss layer, and a pressure of 1.0 atm to 4.0 atm is applied to promote the transfer film. After the transfer film coats the target, the polymethyl methacrylate is then stimulated by ultraviolet rays to undergo a cross-linking reaction to harden and fix to the target. Since the arithmetic mean roughness of the bonding surface of the substrate is extremely small (less than the arithmetic mean roughness of the surface of the target), the present invention can be separated from the high-gloss layer cured and fixed to the target without the aid of a release layer. , and does not affect the specular effect of the specular layer.

According to the present invention, the adhering surface of the high-gloss layer of the transfer film is directly adhered to the surface of the target, and there is no need to attach the high-gloss layer and the target by an additional adhesive layer. In other words, the surface of the above-mentioned object is in direct contact with the adhering surface of the above-mentioned high-gloss layer, without further including the adhesive layer.

According to the present invention, the material of the subject matter can be selected from the group consisting of plastic, metal and glass, but not limited thereto.

Preferably, the plastic comprises polycarbonate (PC), polypropylene (PP), polyester, polyethylene terephthalate (PET), acrylonitrile-butadiene-styrene (ABS), polyurethane ( PU) or thermoplastic elastomer (TPE), but not limited thereto.

According to the present invention, the subject matter can be selected from the group consisting of mobile phones, tablet computers, protective shells, home appliances, automobiles and motorcycles, beauty care products, accessories and decorative plates, but not limited thereto.

In one embodiment, the surface of the target can be a flat surface or a curved surface.

In another embodiment, the subject has a convex portion or a concave portion, and any one of the length, width and height of the convex portion or the concave portion is less than 500 mm. Preferably, any one of the length, width and height of the convex or concave portion is greater than 0 mm to 100 mm.

The bonding surface of the high-gloss layer of the transfer film is directly bonded to the convex part and/or the concave part of the target.

The transfer film of the present invention has good ductility, so it can be applied to objects of different sizes arbitrarily.

If mirror decoration is required for a large-area object, such as the overall outer surface of a car, the length and/or width of the surface of the object may be greater than 1.5 meters; preferably, the length of the surface of the object And/or the width is greater than 2 meters; more preferably, the length and/or width of the surface may be greater than 2 meters and less than 5 meters.

If mirror decoration is required for small-area objects, such as mobile phone cases or accessories, the length and/or width of the surface of the object may be less than 500 mm; preferably, the surface length and/or The width may be greater than or equal to 0.1 mm to less than or equal to 200 mm.

To sum up, the transfer film of the present invention can not only solve the technical defects of water electroplating, vacuum electroplating, water transfer printing and spraying in the past, but also omit the need to use a release layer, a mirror surface layer or a mirror-like release layer in the past transfer film. Limit, and then ensure that after the transfer film is applied to the target, the surface of the target can have the effect of mirror reflection, and the aesthetics and functionality of the target can be improved. In addition, the types of objects that can be applied to the transfer film of the present invention are not limited to the objects of metal materials, so the transfer film of the present invention has a wider application range and excellent market potential.

10: Transfer film

20: The subject matter

21: First transfer area

22: Second transfer area

23: The third transfer area

100: Substrate

101: Joint surface

110: Highlight layer

111: Mirror

112: Fitting surface

201: Surface

202: Large surface area

203: Small Area Surfaces

2011: Bulge

2012: Recess

2013: Vents

2014: Extended platform

2015: Surface

FIG. 1 is a schematic side view of the transfer film.

2A to 2D are schematic diagrams of different implementations of the subject matter, respectively.

FIG. 3 is a schematic cross-sectional view of an embodiment in which the subject object is a housing.

FIG. 4 is a perspective view of an embodiment of a high-gloss layer attached to a target after the transfer film is applied to the target.

Several examples are provided below to illustrate the implementation of the present invention; those skilled in the art can easily understand the advantages and effects that the present invention can achieve through the content of this specification, and make various modifications and effects without departing from the spirit of the present invention. modifications to implement or apply the teachings of the present invention.

"Transfer Film"

As shown in FIG. 1 , the transfer film 10 includes a substrate 100 and a high-gloss layer 110 disposed on the substrate 100 . The substrate 100 has a bonding surface 101 , and the high-gloss layer 110 has an opposite mirror surface 111 and A bonding surface 112, the mirror surface 111 of the high-gloss layer 110 is directly connected to the bonding surface 101 of the substrate 100 Contact, the arithmetic mean roughness of the joint surface 101 of the substrate 100 is less than 1.5 microns, the material of the substrate 100 comprises polyethylene composition, and the material of the high gloss layer 110 comprises polymethyl methacrylate.

The transfer film 10 can be applied to various types of objects, thereby giving the objects a mirror reflection effect; Kitchen utensils, automobiles, decorative plates, etc., but not limited to this.

In one embodiment, the subject matter can be a pressed powder box. After the transfer film is applied to the compact box, as shown in FIG. 2A , the surface 201 of the compact box is a curved surface, and the surface 201 of the compact box is attached to the bonding surface 112 of the high-gloss layer 110 so that the high-gloss layer can pass through. 110 makes the appearance of the compact powder box show the visual effect of mirror reflection.

In another embodiment, the target object may be an ornament. As shown in FIG. 2B , the ornament has a large area surface 202 and a small area surface 203 ; after the transfer film is applied to the ornament, the large area of the ornament The surface 202 and the small-area surface 203 are adhered to the high-gloss layer 110 , so that the overall appearance of the ornament can show the visual effect of mirror reflection through the high-gloss layer 110 . Although the width of the small-area surface 203 is only 3 mm, the high-gloss layer 110 can still fit well on the small-area surface 203 without wrinkling, thereby enhancing the texture and fineness of the overall appearance of the jewelry.

In yet another embodiment, the subject can be a mobile phone. As shown in FIG. 2C , a convex portion 2011 (such as a camera lens) can be provided on the mobile phone; after the transfer film is applied to the mobile phone, the convex portion of the mobile phone can be formed on the mobile phone. The 2011 area will not be attached to the high-gloss layer 110 . Therefore, the high-gloss layer 110 in this area will be taken away by the substrate 100 when peeled off, thereby freeing the camera lens position so that subsequent mobile phone lenses can be directly assembled. Although the height of the protruding portion 2011 is only 0.5 mm, the high-gloss layer 110 can still fit well on the side of the protruding portion 2011 without wrinkling, and the overall appearance of the protruding portion 2011 can be seen from different angles. It can show a mirror reflection effect, thereby improving the texture and detail of the overall appearance of the mobile phone.

In yet another embodiment, the target object may be a tablet computer. As shown in FIG. 2D , a concave portion 2012 may be formed on the tablet computer. After the transfer film is applied to the tablet computer, due to the setting on the concave portion 2012 The exhaust hole 2013 of the tablet can be vacuumed to further enhance the adhesion effect of the high-gloss layer 110 being sucked to the concave part 2012, so that the concave part 2012 of the tablet computer can be more closely adhered to the high-gloss layer 110, thereby allowing the high-gloss to pass through. The layer 110 enables the overall appearance of the tablet computer to exhibit the visual effect of specular reflection. Although the depth of the concave portion 2012 is only 2 mm, the high-gloss layer 110 can still fit well on the concave portion 2012 without wrinkling, and the overall appearance of the concave portion 2012 can exhibit specular reflection when viewed from different angles effect, thereby enhancing the texture and detail of the overall appearance of the tablet. According to different product requirements, the subject matter 20 may have a plurality of concave portions 2012, and these concave portions 2012 may form a trademark.

Example 1: The transfer film of Example 1 has a base material and a high-gloss layer, wherein the base material is a commercial product, and the arithmetic average roughness of its joint surface is about 0.08 microns, and the material of the base material comprises modified poly Ethylene (MdPE, its degree of polymerization is 2400, the MdPE has repeating units of the above-mentioned formula I and formula II structure) and 10% to 11% of plasticizer, the elongation at break in both longitudinal and transverse directions of the substrate is 400% to 500 %, the thickness of the substrate is 75 microns; the material of the high gloss layer includes poly(methyl methacrylate) (PMMA for short), and the thickness of the high gloss layer is 25 microns to 30 microns.

Comparative Example 1: The transfer film of Comparative Example 1 has a substrate, a mirror-like release layer and a high-gloss layer, wherein the substrate is a commercially available product, and its material is a polyethylene (PE) and polypropylene (PP) polymer. Alkene film (ie PO film).

Comparative Example 2: The transfer film of Comparative Example 2 has a base material and a high-gloss layer, wherein the base material is a commercial product, the material is a polyethylene terephthalate film (ie a PET film), and its elongation at break is 75 %, and the highlight layer is the same as in Example 1.

"Application of Transfer Film"

Examples 2 to 4 are all applications of the transfer film of Example 1, respectively transferring the transfer film of Example 1 to an unprinted metal object (Example 2), to An ink-printed plastic target (Example 3) and transfer to a non-ink-printed plastic target (Example 4).

Comparative Example 3, Comparative Example 5 and Comparative Example 7 are all applications of the transfer film of Comparative Example 1, respectively transferring the transfer film of Comparative Example 1 to an unprinted metal target (Comparative Example 3) , transferred to a plastic target printed with ink (Comparative Example 5) and transferred to a plastic target not printed with ink (Comparative Example 7).

Comparative Example 4, Comparative Example 6 and Comparative Example 8 are all applications of the transfer film of Comparative Example 2, respectively transferring the transfer film of Comparative Example 2 to an unprinted metal target (Comparative Example 4) , transferred to a plastic target printed with ink (Comparative Example 6) and transferred to a plastic target not printed with ink (Comparative Example 8).

"Application Comparison Test of Transfer Film"

As shown in FIG. 3 , the effect of applying the transfer film to the objects (shells) of different materials and different transfer areas of Examples 2 to 4 and Comparative Examples 3 to 8 was observed with the naked eye. The transfer yield of the glossy layer 110 of the transfer film and its visual effects in different transfer areas were evaluated for its transfer efficiency. The target object has a first transfer area 21, a second transfer area 22 and a third transfer area 23, and the first transfer area 21 is the main surface (ie the largest surface) of the target object, with an area size of about 130 cm ² ; The second transfer area 22 is the side surface of the target object, with an area of about 24 cm ² ; the third transfer area 23 is the surface of the bottom of the object, and the third transfer area 23 is parallel to the first transfer area 21, with an area of about 24 cm 2 . The size is about 4.8 cm ² , and the results are shown in Table 1.

O: Indicates that the target object exhibits a specular reflection effect after transfer.

△: Indicates that the transfer yield is 30% to 60% or ripples or orange peel occurs.

X: Indicates that the transfer yield is lower than 30% or cannot be attached.

First of all, it can be seen from Example 2 to Example 4 that regardless of whether the material of the target object is metal or plastic, the transfer effect of the transfer film of Example 1 will not be affected, and the target object of Example 2 to Example 4 will not be affected. The overall appearance can show the visual effect of specular reflection.

Second, it can be seen from Example 3 and Example 4 that no matter whether the surface of the target object is coated with ink or not, the transfer effect of the transfer film of Example 1 will not be affected, but the target object of Example 3 and Example 4 will not be affected. The overall look gives the visual effect of a specular reflection.

Third, from the data of Comparative Example 3, Comparative Example 5 and Comparative Example 7, it can be seen that the transfer yield in the third transfer area is only 30% to 60% or there is ripple or orange peel, indicating that when the substrate is When using PO film, because of the extra mirror-like release layer, the overall shape variable is insufficient, and it is not easy to adhere to the surface of the target object.

Finally, from the data of Comparative Example 4, Comparative Example 6 and Comparative Example 8, it can be seen that although only the high-gloss layer is attached to the target, when the base material is PET film, its ductility is poor, and wrinkles are easily generated, resulting in turning The printing film cannot be attached to the second and third transfer areas, so it is still difficult to be used in the market.

"Testing of the bonding effect of transfer film"

As shown in FIG. 4, the subject object is an ornament, and the ornament is provided with a convex part 2011, an extension platform 2014 and a curved surface 2015, and the convex part 2011, the extension platform 2014 and the curved surface 2015 are integrally formed; After the printing film is applied to the ornament, the high-gloss layer 110 can be attached to the convex portion 2011, the extension platform 2014 and the curved surface 2015, so that the overall appearance of the ornament can show the visual effect of mirror reflection; wherein, Although the flat width of the extension platform 2014 is less than 1 mm, and the circumferential length of the extension platform 2014 can be more than 3 cm, the high-gloss layer 110 can still fit well on the extension platform 2014 and its intersection with the convex portion 2011 and the curved surface 2015. On the top, without wrinkles, so this creation has an excellent fit effect.

To sum up, the present invention provides a technical means that is different from the previous technical means that need to use water electroplating, vacuum electroplating, water transfer printing and spraying to obtain the mirror reflection effect. On the subject of the effect, the surface of the subject can be modified through the high-gloss layer of the transfer film as scheduled, and the subject can be given the visual effect of specular reflection, regardless of the material of the subject, whether the surface is pre-formed with ink or whether it is provided with a detailed structure. All of the transfer films can give the target object the visual effect of mirror reflection and have a good transfer rate, thereby enhancing the texture, detail and value of the overall appearance of the target object.

The above embodiments are only examples for the convenience of description, but the embodiments are not used to limit the scope of the patent application of the present invention; any other changes, modifications and other changes that have been completed without departing from the disclosure of the present invention shall be included in the present invention. This invention covers the scope of the patent.

10: Transfer film

100: Substrate

101: Joint surface

110: Highlight layer

111: Mirror

112: Fitting surface

Claims (9)

A transfer film, comprising: a base material and a high-gloss layer arranged on the base material, the base material has a bonding surface, the high-gloss layer has an opposite mirror surface and a bonding surface, and the mirror surface of the high-gloss layer is In direct contact with the joint surface of the substrate, the arithmetic mean roughness of the joint surface of the substrate is less than 1.5 microns, the longitudinal elongation at break of the substrate is 300% to 600%, and the transverse elongation at break of the substrate is 300% to 600%, and the material of the base material includes a polyethylene-based composition, and the polyethylene-based composition has a hydroxyl group (-OH), and the material of the high-gloss layer includes polymethyl methacrylate. The transfer film as claimed in claim 1, wherein the polyethylene-based composition comprises the following repeating units of formula I and formula II:

Among them, n1 is a natural number greater than or equal to 0 and less than 5000, and n2 is a natural number greater than 0 and less than 5000. The transfer film according to claim 2, wherein the n1 is 0, and the repeating unit of the polyethylene-based composition is composed of formula II. The transfer film according to claim 1, wherein the degree of polymerization of the polyethylene-based composition is 2000 to 3000. A use of a transfer film, comprising applying the transfer film as described in any one of claims 1 to 4 on a target. The use according to claim 5, wherein the object has a surface, and the surface is a flat surface or a curved surface. The use according to claim 5, wherein the bonding surface of the high-gloss layer of the transfer film is directly bonded to the surface of the object. The use according to claim 5, wherein the subject matter has a convex portion or a concave portion, any one of the length, width and height of the convex portion or the concave portion is less than 500 mm, and the highlight layer of the transfer film has a The bonding surface is directly bonded to the convex or concave portion. The use according to any one of claims 5 to 8, wherein the material of the subject matter is selected from the group consisting of plastic, metal and glass.

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