CN115087546A

CN115087546A - Decorative film and decorative molded body

Info

Publication number: CN115087546A
Application number: CN202180013957.8A
Authority: CN
Inventors: 山本真之; 川浪悠生
Original assignee: Oji Holdings Corp
Current assignee: Oji Holdings Corp
Priority date: 2020-02-12
Filing date: 2021-02-12
Publication date: 2022-09-20
Also published as: WO2021162088A1; JP2021126785A; JP7467962B2

Abstract

The present invention addresses the problem of providing a decorative film that exhibits excellent adhesion to an adherend comprising a polypropylene resin and has excellent blocking resistance to a mold. The present invention relates to a decorative film for decorating an adherend containing a polypropylene resin, which comprises a base material having a decorative layer, an adhesive layer, and a polypropylene layer in this order. The present invention also relates to a decorative molded article obtained by bonding a decorative film to an adherend comprising a polypropylene resin.

Description

Decorative film and decorative molded body

Technical Field

The present invention relates to a decorative film and a decorative molded body.

Background

Conventionally, when the surface of an automobile interior and exterior part, a household electrical appliance part, a building material part, or the like is protected or decorated (decorated), the following operations are performed: after a molded body is processed by injection molding or vacuum molding, a coating material is applied to the surface of the molded body by spray coating or the like, and the molded body is dried and cured by heating. However, such coating has problems that the discharge of the volatile organic solvent deteriorates the working environment, and that the finished product rate of the coating material is poor and the productivity is low because the working process and the production facility are required for each molded part and the coating material is repeatedly applied.

In recent years, resin molded articles have been used as molded articles for the purpose of reducing the weight of automobile interior and exterior parts, household electrical appliances, building material parts, and the like. In many cases, spray coating is not suitable for decorating (decorating) a resin molded product, and various methods have been developed for decorating the surface of the resin molded product. Among them, the method of obtaining a decorative molded article by decorating the outermost surface of the molded article with a decorative film has advantages of high degree of freedom in design and excellent productivity as compared with the method of coating or printing on the surface using a paint or the like. In addition, a decoration method using a decorative film is used for various purposes because a surface of a molded body having three-dimensional irregularities can be decorated.

For example, patent document 1 discloses a decorative molding laminate including a base layer and an adhesive layer, wherein the adhesive layer includes a silicone adhesive layer and an acrylic adhesive layer. Further, patent document 2 discloses a vacuum molding sheet having an adhesive layer on the lower surface of a surface film. The adhesive layer is obtained by mixing 1.5-2.5 equivalents of polyisocyanate into thermoplastic saturated copolyester resin and curing.

Patent document 3 discloses a decorative film used in an injection molding simultaneous transfer decoration method. Here, a three-dimensional molded decorative film for injection molding and simultaneous transfer is disclosed in which a release layer, a protective layer, a colored layer, and an adhesive layer are laminated in this order on a base material, and examples of the resin used for the adhesive layer include resins such as acrylic resins, vinyl chloride resins, vinyl acetate resins, vinyl chloride-vinyl acetate copolymer resins, styrene-acrylic copolymer resins, polyester resins, and polyamide resins.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2017-154410

Patent document 2: japanese patent application laid-open No. 2010-120209

Patent document 3: japanese patent laid-open publication No. 2011-

Disclosure of Invention

Problems to be solved by the invention

In the decorative molded article, it is required that the adherend and the decorative film are sufficiently adhered to each other and not easily peeled off. However, when a material of polypropylene resin is used as an adherend, there is a problem that if a conventional adhesive sheet (decorative film) for decorative molding is used, the adhesiveness to the decorative film of the adherend cannot be sufficiently exhibited.

In addition, in the production of a decorative molded article, a method of bonding a decorative film to an adherend by film insert molding or in-mold molding is sometimes used. In this case, the decorative film may be die-processed to have a desired shape before the molten resin constituting the adherend is injected. However, in such a processing step, if the decorative film is not peeled off from the processing mold, it may be difficult to process the decorative film into a desired shape. Thus, if a defect occurs in the finishing stage of the decorative film, the production efficiency of the decorative molded article may be significantly reduced, and unexpected defects may occur in the decorative film itself, which may cause a problem.

Therefore, the present inventors have made studies to solve the problems of the prior art as described above, with the object of providing a decorative film which exhibits excellent adhesion to an adherend comprising a polypropylene resin and has excellent blocking resistance to a mold.

Means for solving the problems

As a result of intensive studies to solve the above problems, the present inventors have found that a decorative film exhibiting excellent adhesion to an adherend comprising a polypropylene resin and excellent blocking resistance to a mold can be obtained by laminating a base material having a decorative layer, an adhesive layer, and a polypropylene layer in this order in the decorative film.

Specifically, the present invention has the following configuration.

[1] A decorative film comprising a substrate having a decorative layer, an adhesive layer and a polypropylene layer in this order,

which is used for decorating an adherend comprising a polypropylene resin.

[2] The decorative film according to [1], wherein the adhesive layer comprises:

a block copolymer comprising a block made from a structure derived from isopentane and a block made from a styrenic polymer; and

a terpene-based resin.

[3] The decorative film according to [2], wherein the terpene-based resin is at least 1 selected from the group consisting of terpene resins, aromatic modified terpene resins and terpene phenol resins,

the softening point of the terpene resin is 60 to 130 ℃,

the terpene resin has a number average molecular weight of 300 to 1500.

[4] The decorative film according to [2] or [3], wherein the content of the terpene resin is 40 to 200 parts by mass per 100 parts by mass of the block copolymer.

[5] The decorative film according to any one of [1] to [4], wherein the adhesive layer has a thickness of 0.5 to 20 μm.

[6] The decorative film according to any one of [1] to [5], wherein the polypropylene layer has a thickness of 1 to 30 μm.

[7] The decorative film according to any one of [1] to [6], which is used for decorating an adherend by a film insert molding method or an in-mold molding method.

[8] A decorative molded article obtained by bonding the decorative film according to any one of [1] to [7] to an adherend comprising a polypropylene resin.

[9] The decorative molded article according to [8], which is used for automobile parts, electronic devices or building materials.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, a decorative film can be obtained which exhibits excellent adhesion to an adherend comprising a polypropylene resin and which has excellent blocking resistance to a mold.

Drawings

FIG. 1 is a cross-sectional view showing an example of the structure of the decorative film.

FIG. 2 is a sectional view showing an example of the structure of the decorative molded article.

Detailed Description

The present invention will be described in detail below. The following description of the constituent elements may be based on a representative embodiment and a specific example, but the present invention is not limited to such an embodiment. In the present specification, the numerical range expressed by the term "to" means a range including the numerical values described before and after the term "to" as the lower limit value and the upper limit value.

(decorative film)

The present invention relates to a decorative film comprising a substrate having a decorative layer, an adhesive layer, and a polypropylene layer in this order. The decorative film of the present invention is used for decorating an adherend comprising a polypropylene resin. The decorative film of the present invention has the above-described configuration, and therefore exhibits excellent adhesion to an adherend comprising a polypropylene resin. Therefore, the decorative film of the present invention is preferably used for bonding to an adherend containing a polypropylene resin as a main component. Further, the decorative film of the present invention has the above-described structure, and therefore, has excellent blocking resistance against a mold. That is, the decorative film of the present invention is excellent in releasability from a mold. Therefore, when the decorative film is subjected to the mold processing, the decorative film is easily peeled off from the processing mold, and can be smoothly moved to the subsequent bonding step with the adherend. Further, since the decorative film is easily peeled from the processing mold, the occurrence of defects in the decorative film can be suppressed, and the design of the decorative molded article is not impaired.

Conventionally, polycarbonate resins and ABS resins have been used as adherends for decorating molded articles. Therefore, the specific structure of the decorative film for decorating an adherend containing a polypropylene resin as a main component has not been sufficiently studied. Further, in the case of producing a decorative molded article by decorating an adherend, there are cases where a film insert molding method or an in-mold molding method is used, but there are problems concerning the processability and the processing efficiency of the decorative film in this case. The present inventors have made extensive studies and studies on the layer structure of the decorative film, and as a result, produced a decorative film in which a polypropylene layer is laminated on the outermost layer of the decorative film, and the decorative film includes a substrate having a decorative layer, an adhesive layer, and a polypropylene layer in this order. As a result, a decorative film which exhibits excellent adhesion to an adherend containing a polypropylene resin as a main component and which is easily peeled from a processing mold when the decorative film is subjected to mold processing has been successfully obtained.

FIG. 1 is a sectional view illustrating an example of the structure of the decorative film of the present invention. As shown in fig. 1, the decorative film 30 includes a substrate 10 having a decorative layer, an adhesive layer 12, and a polypropylene layer 14 in this order. In the decorative film 30, another layer may be provided between the layers, but in the present embodiment, it is preferable that the substrate 10 having the decorative layer and the adhesive layer 12 are laminated in direct contact, and the adhesive layer 12 and the polypropylene layer 14 are also laminated in direct contact. It is particularly preferred that the adhesive layer 12 is laminated in direct contact with the polypropylene layer 14. As shown in fig. 1, by disposing the polypropylene layer 14 on the outermost layer of the decorative film 30, the decorative film 30 can exhibit excellent adhesion to an adherend containing a polypropylene resin as a main component. The decorative film 30 has a structure as shown in fig. 1, and therefore has excellent blocking resistance against a mold.

In fig. 1, the substrate 10 having the decorative layer is depicted as a single layer for convenience, but the substrate 10 having the decorative layer may be a single layer composed of the decorative layer or may have a multilayer structure including at least the substrate and the decorative layer. Among them, the substrate 10 having the decorative layer is preferably a multilayer structure including a substrate and a decorative layer. In the case where the substrate 10 having a decorative layer includes a substrate and a decorative layer, the decorative layer in the substrate 10 having a decorative layer may be provided so as to be in contact with the adhesive layer 12. In this case, the substrate of the substrate 10 having the decorative layer is disposed on the outermost layer of the decorative film. Further, a layer such as an easy-adhesion layer for improving adhesion may be provided between the decorative layer and the adhesive layer 12.

When the decorative film of the present invention is used for film insert molding, a functional layer such as a hard coat layer or an antireflection layer different from the decorative layer may be provided on the outermost layer (the surface opposite to the surface in contact with the adhesive layer 12) of the substrate 10 having the decorative layer.

On the other hand, when the decorative film of the present invention is used for in-mold molding, it is preferable that the decorative layer of the substrate 10 having the decorative layer is necessarily provided on the surface in contact with the adhesive layer 12, and a substrate having releasability so that the substrate and the decorative layer are easily peeled off after molding is used, or a release layer is provided between the substrate and the decorative layer, whereby the substrate (release layer) and the decorative layer are configured to be in contact with each other.

The decorative film of the present invention is preferably used for decorating an adherend by film insert molding or in-mold molding. In the film insert molding method and the in-mold molding method, a decorative film is processed into a 3-dimensional shape in advance, and then placed in a cavity of a mold, and a molten resin constituting an adherend is injected into the mold, whereby a decorative molded article in which the decorative film and the adherend are integrated is obtained.

(adhesive layer)

The decorative film has an adhesive layer. In the present invention, a base material having a decorative layer and a polypropylene layer are laminated on both surfaces of the adhesive layer, respectively, and the adhesive layer is not exposed in the decorative film.

In the present embodiment, the adhesive layer preferably contains a block copolymer and a terpene resin. Here, the block copolymer comprises a block made of a structure derived from isopentane and a block made of a styrenic polymer. The content of the terpene resin is preferably 40 parts by mass or more, more preferably 45 parts by mass or more, further preferably 50 parts by mass or more, and particularly preferably 55 parts by mass or more, per 100 parts by mass of the block copolymer. The content of the terpene resin is preferably 200 parts by mass or less, more preferably 180 parts by mass or less, still more preferably 160 parts by mass or less, still more preferably 140 parts by mass or less, and particularly preferably 120 parts by mass or less, per 100 parts by mass of the block copolymer. Is preferred. When the content of the terpene resin is in the above range, the interlayer adhesiveness between the adhesive layer and the polypropylene layer can be improved, and further, the interlayer adhesiveness between the adhesive layer and the base material having the decorative layer can be improved. That is, by setting the content of the terpene resin within the above range, the adhesion to the polypropylene layer can be effectively improved within a range not impairing the blocking resistance of the decorative film.

The total content of the block copolymer and the terpene resin is preferably 50 mass% or more, and more preferably 60 mass% or more, based on the total mass of the adhesive layer. The total content of the block copolymer and the terpene resin may be 100% by mass based on the total mass of the adhesive layer. By setting the total content of the block copolymer and the terpene resin to the above range, the adhesive layer can more effectively improve the interlayer strength with the base material having the decorative layer and the polypropylene layer. That is, by setting the terpene resin content within the above range, the adhesion to the polypropylene layer can be effectively improved within a range not impairing the blocking resistance of the decorative film.

The adhesive layer comprises a block copolymer comprising a block made of a structure derived from isopentane and a block made of a styrenic polymer. In the present specification, the structure derived from isopentane is as follows. Further, the block derived from the structure derived from isopentane is a block obtained by polymerizing the structure derived from isopentane of the above-mentioned structure. In addition, the structure derived from isopentane is preferably a propylene/ethylene copolymer.

The block made of a styrenic polymer is preferably a block made of a styrene polymer, an α -methylstyrene polymer.

The adhesive layer may contain a block copolymer containing a block made of another polymer in addition to a block made of an isopentane-derived structure and a block made of a styrene-based polymer. Examples of the block made of another polymer include a block made of a structure derived from ethylene, a block made of a (meth) acrylate-based polymer, and the like.

In the block copolymer included in the adhesive layer, when a block derived from isopentane and a block derived from a styrene-based polymer are represented by a and B, the block copolymer may be a diblock copolymer having an a-B structure, or a triblock copolymer having an a-B-a structure or a B-a-B structure. Further, a block copolymer having a repeating structure of each block, such as a-A-B-A-B-structure, may be used. Further, as described above, the block copolymer may further include a block made of another polymer.

The block copolymer included in the adhesive layer may further have a substituent in its polymer chain, and for example, a block copolymer having a substituent having an unsaturated bond as a substituent may be used.

The block copolymer can be produced by polymerization by a known method, but a commercially available product can be used. Commercially available products include, for example, セプトン 1020, セプトン 2002, セプトン 4033, セプトン HG252 available from クラレ co.

The terpene resin contained in the adhesive layer is preferably at least 1 selected from the group consisting of terpene resins, aromatic modified terpene resins, and terpene phenol resins. More specifically, the terpene resin may be an α -pinene polymer, a β -pinene polymer, a dipentene polymer, or a terpene resin obtained by subjecting these to phenol modification, aromatic modification, hydrogenation modification, or hydrocarbon modification.

The softening point of the terpene-based resin is preferably 60 ℃ or higher, more preferably 65 ℃ or higher, still more preferably 70 ℃ or higher, and particularly preferably 75 ℃ or higher. The terpene-based resin may have a softening point of 100 ℃ or higher. The softening point of the terpene-based resin is preferably 130 ℃ or lower, more preferably 125 ℃ or lower. The softening point of the terpene-based resin was measured by an automatic softening point measuring apparatus (EX-719 PD4, manufactured by FLEX SCIENTIFIC) in accordance with the method described in JIS K2207.

The number average molecular weight of the terpene-based resin is preferably 300 or more, more preferably 350 or more, and further preferably 400 or more. The number average molecular weight of the terpene-based resin is preferably 1500 or less, more preferably 1400 or less, and still more preferably 1300 or less. The number average molecular weight of the terpene-based resin is a value obtained by measuring the molecular weight by Gel Permeation Chromatography (GPC) and converting the molecular weight into a standard curve prepared using standard polystyrene having a known molecular weight.

As the terpene-based resin, commercially available products can be used. Commercially available products include, for example, YS レジン PX 1150, YS レジン PX 1250, YS レジン TO 125, YS レジン TO 105, YS ポリスター T125, YS ポリスター T80, and YS ポリスター G125 manufactured by ヤスハラケミカル co.

The adhesive layer may contain an additive in addition to the block copolymer and the resin. Examples of the additives include antioxidants (or antioxidants), silane coupling agents, tackifiers other than terpene resins, oil components, softeners, crosslinking agents, pigments, hydrogen abstraction initiators, and the like.

Examples of the antioxidant include a phenol-based antioxidant, an amine-based antioxidant, a lactone-based antioxidant, a phosphorus-based antioxidant, and a sulfur-based antioxidant. These antioxidants may be used alone in 1 kind, or may be used in combination of 2 or more kinds.

Examples of the silane coupling agent include mercapto silane coupling agents containing mercapto groups, epoxy silane coupling agents having epoxy groups, and vinyl silane coupling agents having vinyl groups. Among them, mercapto silane coupling agents are preferably used in the use of the present invention. Examples of the mercapto silane coupling agent include mercaptotrimethoxysilane, mercaptomethyltrimethoxysilane, mercaptomethyltriethoxysilane, triethoxy (2-mercaptoethyl) silane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 4-mercaptobutyltrimethoxysilane, 10-mercaptodecyltriethoxysilane, 11-mercaptoundecyltrimethoxysilane, and 11-mercaptoundecyltriethoxysilane.

Examples of the tackifier other than the terpene-based resin include petroleum-based resins such as styrene-based resins, rosin-based resins, C5-based resins, C9-based resins, and C5/C9-based resins.

The oil component is preferably a paraffin-based or naphthenic system oil, and a paraffin-based system oil is more preferably used for the reason that deterioration of rubber is not likely to occur.

Examples of the hydrogen abstraction initiator include benzophenone compounds such as methyl benzoylformate and tetramethylbenzophenone.

The thickness of the adhesive layer is preferably 0.5 μm or more, and more preferably 1 μm or more. The thickness of the adhesive layer is preferably 20 μm or less, more preferably 15 μm or less, and still more preferably 10 μm or less. In the present embodiment, the thickness of the adhesive layer can be reduced.

(substrate with decorative layer)

The decorative film comprises a substrate having a decorative layer. Here, the substrate having the decorative layer preferably includes a film-shaped substrate and a decorative layer.

The decorative layer constituting the substrate having the decorative layer may be a layer provided on the outermost surface (the surface opposite to the side in contact with the adhesive layer) of the decorative film, may be a layer provided on the side in contact with the adhesive layer, and is preferably a layer provided on the surface in contact with the adhesive layer. In particular, in the case where the decorative film is used for in-mold molding, the decorative layer needs to be provided on the surface in contact with the adhesive layer. On the other hand, in the case where the decorative film is used for film insert molding, the decorative layer is preferably provided on the outermost surface (the surface opposite to the side in contact with the adhesive layer) of the decorative film, and in this case, a functional layer such as a hard coat layer or an antireflection layer may be further provided on the outermost layer.

The decorative layer is preferably a printed layer. The printed layer is formed by printing on one surface side of the film-shaped substrate using an ink containing a thermosetting resin, an ultraviolet-curable resin, or the like as a main component, for example. The printing may be performed by a known printing method such as inkjet printing or screen printing. Examples of the film-shaped substrate to be printed include ABS resin (a copolymer of acrylonitrile, butadiene, and styrene), AS resin (a copolymer of acrylonitrile and styrene), acrylic resin, polyethylene terephthalate, polybutylene terephthalate, nylon, polyacetal, polyphenylene ether, phenol resin, urea resin, melamine resin, liquid crystal polymer, polytetrafluoroethylene, poly-1, 1-difluoroethylene, polysulfone, polyethersulfone, polyacetal, polyether ether ketone, polyphenylene sulfide, polyetherimide, polyamideimide, polycarbonate, polyolefin resin (polyethylene, polypropylene, etc.), polystyrene, urethane resin, and the like. These base materials are preferably capable of being stretched in a shape following the adherend in the molding step. In addition, although a transparent film is generally used as the film-shaped substrate, a coloring agent such as carbon (graphite) may be mixed and used as a colored layer in order to impart design properties.

The substrate having the decorative layer may further have a surface protective layer or a print protective layer for protecting the print layer. The surface protection layer is preferably a layer that is disposed on the exposed outermost surface side of the substrate having the decorative layer and that functions to improve abrasion resistance and weather resistance. Therefore, the surface protective layer is preferably a layer including a curable resin layer, and more preferably a hard coat layer. Among them, the curable resin is preferably a photocurable resin, and more preferably an ultraviolet curable resin. In this case, the resin composition for forming the surface protective layer preferably contains a photopolymerization initiator in addition to the ultraviolet curable resin, for example. In addition, in the case where the decorative layer is formed by printing, since the decorative layer is easily scratched by the ink used, a print protection layer such as a hard coat layer may be provided on the ink layer in order to prevent scratching.

The surface protective layer may further comprise particles. The fine particles include, for example, inorganic fine particles, and preferably, metal oxides can be exemplified. Further, pigments and dyes may be contained as required. The surface protective layer may contain additives such as a pigment dispersant, a defoaming agent, an ultraviolet absorber, a HALS (hindered amine light stabilizer), an antioxidant, an antistatic agent, an anti-abrasion agent, and an anti-blocking agent, as required.

The substrate having the decorative layer may further include a protective film, and in the case where the outermost layer has an adhesive layer, may further include a release layer. The protective film and the spacer are provided to temporarily protect the surface protective layer. For example, the protective layer may be provided to prevent scratches on the surface protective layer, the printed layer, or the like before use. The protective film is preferably a self-adhesive film made of an ethylene-vinyl acetate copolymer, or a micro-adhesive film in which a urethane-based and/or acrylic-based removable adhesive layer is laminated on a PET film or the like. The separation layer is preferably configured by providing a separation layer such as silicone on the surface of the base layer as described above. Such a barrier layer is peeled off in the production process and in use, and is removed from the decorative film or the decorative molded body.

Examples of the structure of the substrate having the decorative layer include the following layer structures. In addition, in order to bond the layers, an adhesive layer or an easily adhesive material layer may be provided between the layers as necessary.

(1) A substrate layer, a printing layer and a printing protective layer

(2) A surface protective layer, a printing layer and a base material layer

(3) A substrate layer and a printing layer are sequentially arranged

(4) A functional layer, a substrate layer and a printing layer

(generally the constitution is used for film insert molding and not for in-mold molding)

(5) A substrate layer, a release layer, a printing protective layer, and a printing layer

(generally the constitution is used for in-mold molding and not for film insert molding)

(6) A structure in which a protective film is further provided on the outermost surface of the structures (1) to (5)

(7) A structure in which an adhesive layer and a separator are further provided on the outermost surface of the structures (1) to (5)

When an adhesive layer is provided to bond the layers, a known adhesive can be used as the adhesive constituting the adhesive layer. Examples of the adhesive include natural rubber-based adhesives, synthetic rubber-based adhesives, acrylic adhesives, urethane-based adhesives, and silicone-based adhesives. The adhesive may be any of a solvent-based adhesive, a solventless adhesive, an emulsion-based adhesive, and an aqueous adhesive.

(Polypropylene layer)

The decorative film has a polypropylene layer. The thickness of the polypropylene layer is preferably 1 μm or more, more preferably 2 μm or more, and further preferably 3 μm or more. The thickness of the polypropylene layer is preferably 30 μm or less, more preferably 25 μm or less, still more preferably 20 μm or less, still more preferably 15 μm or less, and particularly preferably 10 μm or less.

(method for producing decorative film)

The method for producing a decorative film of the present invention comprises the steps of: a step of forming an adhesive layer by applying an adhesive composition to a substrate having a decorative layer and drying or curing the adhesive composition; and forming a polypropylene layer or attaching a polypropylene film on the adhesive layer. Alternatively, the method for producing a decorative film of the present invention may comprise the steps of: a step of forming an adhesive layer by applying an adhesive composition to the polypropylene layer and drying or curing the adhesive composition; and a step of bonding a base material having a decorative layer to the adhesive layer.

The adhesive composition may be applied by a conventional method. In the case of using an adhesive composition produced by dissolving in a solvent, the adhesive composition may be coated with a knife coater or the like, and then dried in a drying oven to be formed into a sheet. On the other hand, when an adhesive produced by a kneading method using heating is used, the adhesive can be formed into a sheet by using a hot melt coater capable of softening the adhesive composition by heating in advance.

When the polypropylene layer is formed on the adhesive layer formed on the substrate having the decorative layer, a method of bonding a polypropylene film to the adhesive layer and pressure-bonding the same can be employed. As the bonding method, a conventional bonding machine can be used. For example, the adhesive layer and the polypropylene layer may be bonded in combination of roll-to-roll, sheet-to-roll, roll-to-sheet, sheet-to-sheet, and the like, and in this case, it is preferable to bond them while applying pressure with a roll, a roller, and the like. In addition, when the adhesive layer is formed on the polypropylene layer, a substrate having a decorative layer can be attached by the same method.

In addition, when the polypropylene layer is formed on the adhesive layer formed on the substrate having the decorative layer, the polypropylene layer can be formed on the adhesive layer by melt extrusion using a T-die by an extrusion lamination method.

(decorative molding)

The present invention also relates to a decorative molded article obtained by bonding a decorative film to an adherend comprising a polypropylene resin. In addition, in the decorative molded article, the adherend and at least the decorative film (or the decorative layer in the case of in-mold molding) are integrated via the polypropylene layer, and at least a part of the surface of the adherend is covered with the decorative film (or the decorative layer).

FIG. 2 is a sectional view illustrating an example of the structure of the decorative molded article. As shown in fig. 2, the decorative molded article 100 has a structure in which a decorative film 30 is laminated on an adherend 50. As shown in fig. 2, the decorative film 30 includes a substrate (or a decorative layer in the case of in-mold molding) 10 having a decorative layer, an adhesive layer 12, and a polypropylene layer 14, and the polypropylene layer 14 is directly bonded to an adherend 50. In fig. 2, the polypropylene layer 14 is drawn as a layer for easy understanding of the structure of the decorative molded article 100, but in the decorative molded article obtained in practice, the polypropylene layer 14 may be integrated with the adherend 50 and the boundary thereof may not be known.

The adherend comprises a polypropylene resin. Here, the adherend contains a polypropylene resin as a main component. Specifically, the content of the polypropylene resin in the adherend is preferably 50 mass% or more, more preferably 60 mass% or more, and still more preferably 70 mass% or more. In addition, the content of the polypropylene resin in the adherend may be 100 mass%, and the adherend may also be made of a polypropylene resin.

The shape of the adherend comprising the polypropylene resin is not particularly limited, and may be a plate shape and may have a 3-dimensional three-dimensional shape. Further, the adherend may have a concavo-convex structure in a part of the surface thereof.

The decorative molded article is preferably used for automobile parts, electronic devices, or building materials. The present invention may relate to an automobile member, an electronic device or a building material including the decorative molded article. Examples of the automobile member include parts such as a vehicle body, a bumper, a spoiler, a mirror, a wheel, a emblem, and an interior material. Examples of the electronic devices include electronic devices such as home electric appliances and liquid crystal display devices such as personal computers. Examples of the building material include furniture and building materials. Further, the adherend may be a material for roads (e.g., traffic signs, sound-proof walls, etc.), a material for tunnels (e.g., side wall boards, etc.), musical instruments, containers, office supplies, sporting goods, toys, and the like.

(method of producing decorative Molding)

The method for producing a decorative molded article preferably includes a step of bonding a decorative film to an adherend. Examples of the method for producing the decorative molded article include hot press molding, in-mold molding, film insert molding, molding under vacuum or reduced pressure, and the like. Among these, the method for producing the decorative molded article is preferably a film insert molding method or an in-mold molding method, and the decorative film is a decorative film suitable for decorative molding in the film insert molding method or the in-mold molding method.

In the case of in-mold molding, a decorative film is fixed in a mold of an injection molding machine, a resin composition containing a polypropylene resin as a main component constituting an adherend is injected into the mold, and after the resin composition is cured, only the base material of the base material having the decorative layer is removed to obtain a decorative molded article. In addition, as a method for producing a decorative molded article, in the case of using a film insert molding method, a decorative film is fixed in a molding die of an injection molding machine, a resin composition containing a polypropylene resin as a main component is injected into the molding die, and the resin composition is cured to obtain a decorative molded article.

Examples

The features of the present invention will be described in more detail below with reference to examples and comparative examples. The materials, amounts used, ratios, contents of treatment, treatment steps and the like shown in the following examples may be appropriately modified without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited to the specific examples shown below.

< production of adhesive composition >

Adhesive composition (A-1)

100 parts by mass of a block copolymer (セプトン 1020, manufactured by クラレ) having a structure represented by the following structural formula, 60 parts by mass of a terpene resin (manufactured by ヤスハラケミカル, YS レジン PX 1150, having a softening point of 115 ℃, a number average molecular weight of 1000), and 0.6 part by mass of an antioxidant (IRGANOX 1010, manufactured by BASF) were dissolved in toluene so that the solid content concentration became 30 mass%, thereby obtaining an adhesive composition (a-1).

Adhesive composition (A-2)

An adhesive composition (A-2) having a solid content of 30 mass% was obtained in the same manner as in the preparation of the adhesive composition (A-1) except that a resin having a structure represented by the following structural formula (manufactured by クラレ, セプトン 2002) was used as the block copolymer.

Adhesive composition (A-3)

An adhesive composition (A-3) having a solid content concentration of 30 mass% was obtained in the same manner as in the preparation method of the adhesive composition (A-1), except that a resin having a structure represented by the following structural formula (manufactured by クラレ, セプトン 4033) was used as the block copolymer.

Adhesive composition (A-4)

An adhesive composition (a-4) having a solid content of 30 mass% was obtained in the same manner as in the preparation method of the adhesive composition (a-3) except that the terpene resin (manufactured by ヤスハラケミカル, YS レジン PX 1150, having a softening point of 115 ℃ and a number average molecular weight of 1000) was changed to the terpene resin (manufactured by ヤスハラケミカル, YS レジン PX 800, having a softening point of 80 ℃ and a number average molecular weight of 700), and the amount of the terpene resin added was changed to 100 parts by mass.

Adhesive composition (A-5)

An adhesive composition (A-5) having a solid content of 30 mass% was obtained in the same manner as in the preparation method of the adhesive composition (A-3) except that the terpene resin (YS レジン PX 1150, manufactured by ヤスハラケミカル, having a softening point of 115 ℃ and a number average molecular weight of 1000) was changed TO an aromatic modified terpene resin (YS レジン TO 125, manufactured by ヤスハラケミカル, having a softening point of 125 ℃ and a number average molecular weight of 800).

Adhesive composition (A-6)

An adhesive composition (A-6) having a solid content of 30 mass% was obtained in the same manner as in the preparation of the adhesive composition (A-3) except that the terpene-phenol resin (manufactured by ヤスハラケミカル, YS ポリスター T80, having a softening point of 80 ℃ and a number average molecular weight of 500) was used.

Adhesive composition (B-1)

An adhesive composition (B-1) having a solid content of 30 mass% was obtained in the same manner as in the preparation of the adhesive composition (A-1), except that a hydrogenated polybutadiene resin (セプトン 8004, manufactured by クラレ Co.) having no structure derived from isopentane was used instead of the block copolymer having a structure derived from isopentane.

Adhesive composition (B-2)

An adhesive composition (B-2) having a solid content of 30 mass% was obtained in the same manner as in the preparation of the adhesive composition (A-3), except that a styrene resin (FTR 8100, number average molecular weight 800, available from Mitsui chemical) was used instead of the terpene resin.

Adhesive composition (C-1)

In a reaction vessel equipped with a stirrer, a nitrogen gas inlet tube, a thermometer, and a reflux condenser, n-Butyl Acrylate (BA) and 2-hydroxyethyl acrylate (2HEA) were mixed in a mass ratio of 80: 20, 2' -azobis (2, 4-dimethylvaleronitrile) was dissolved in a solution as a radical polymerization initiator. The copolymer solution was obtained by heating the solution to 60 ℃ to thereby randomly copolymerize the monomer components. To 100 parts by mass of the solid content of the copolymer obtained above, 0.11 part by mass of a xylylene diisocyanate compound (タケネート D-110N, manufactured by Mitsui chemical Co., Ltd.) was added as a crosslinking agent, and ethyl acetate was added so that the solid content concentration became 30% by mass, to obtain an adhesive composition (C-1).

Adhesive composition (C-2)

As the acid component, terephthalic acid: isophthalic acid: the mass ratio of adipic acid is 30: 30: 40, 1, 4-butanediol and 1, 6-hexanediol were mixed as diol components in a mass ratio of 25: 75, and heating in the presence of a catalyst (tetrabutyl titanate), thereby obtaining a thermoplastic saturated copolyester resin. The thermoplastic saturated copolyester resin obtained above was dissolved in a solvent (methyl ethyl ketone), diluted and stirred so that the solid content concentration became a solution of 30 mass%. Then, 2 parts by mass of polyisocyanate ("コロネート HX" (1, 6-hexamethylene diisocyanate) manufactured by japan ポリウレタン, with a solid content concentration of 100% by mass) was added to the solution relative to 100 parts by mass of the thermoplastic saturated copolyester resin, thereby obtaining an adhesive composition (C-2).

< manufacture of decorative film >

(example 1)

The adhesive composition (A-1) thus prepared was applied to an acrylic film (manufactured by クラレ, パラピュア HI grade 75 μm) so that the thickness of the dried adhesive layer became 5 μm using a knife coater, and then dried at 100 ℃ for 3 minutes to evaporate toluene as a solvent and dry it. Subsequently, a polypropylene film (EM-5015 μm, product of Wangzi エフテックス Co., Ltd.) was laminated on the adhesive layer side by a hand pressure roller to obtain an ornamental film.

(example 2)

A decorative film was obtained in the same manner as in example 1, except that the adhesive composition (a-1) was changed to the adhesive composition (a-2).

(example 3)

A decorative film was obtained in the same manner as in example 1, except that the adhesive composition (a-1) was changed to the adhesive composition (a-3).

(example 4)

A decorative film was obtained in the same manner as in example 1, except that the adhesive composition (a-1) was changed to the adhesive composition (a-4).

(example 5)

A decorative film was obtained in the same manner as in example 1, except that the adhesive composition (a-1) was changed to the adhesive composition (a-5).

(example 6)

A decorative film was obtained in the same manner as in example 1, except that the adhesive composition (a-1) was changed to the adhesive composition (a-6).

(example 7)

A decorative film was obtained in the same manner as in example 3 except that the thickness of the adhesive layer after drying was changed to 1 μm and the thickness of the polypropylene film was changed to 20 μm (manufactured by Wangzi エフテックス, SS-12120 μm).

(example 8)

A decorative film was obtained in the same manner as in example 3 except that the thickness of the adhesive layer after drying was changed to 20 μm and the polypropylene film was changed to 12 μm (MAM-41112 μm, manufactured by Wangzi エフテックス Co., Ltd.).

Comparative example 1

A decorative film having no polypropylene layer was obtained in the same manner as in example 1, except that the polypropylene film was not laminated.

Comparative example 2

A decorative film was obtained in the same manner as in example 1, except that the adhesive composition (A-1) was changed to the adhesive composition (B-1).

Comparative example 3

A decorative film was obtained in the same manner as in example 1, except that the adhesive composition (a-1) was changed to the adhesive composition (B-2).

Comparative example 4

A decorative film was obtained in the same manner as in example 1, except that the adhesive composition (A-1) was changed to the adhesive composition (C-1).

Comparative example 5

A decorative film was obtained in the same manner as in comparative example 1, except that the adhesive composition (A-1) was changed to the adhesive composition (C-2).

(evaluation of adhesion)

< production of decorative molded article >

Using the decorative films obtained in the examples and comparative examples, a decorative molded article was produced by a film insert molding method. First, a decorative film was placed on the inside of a plate-shaped mold having a molded article size of 100mm × 100mm × 2mm so that the polypropylene layer was on the side of the injected resin. Then, the mold having the decorative film placed thereon was heated to 60 ℃ and then heated to 200 ℃ to melt polypropylene (manufactured by Mitsubishi ケミカル, ノバテック) ^TM PP) was injected into the mold, and after cooling to room temperature, the decorative molded body was taken out of the mold, thereby obtaining a decorative molded body.

< evaluation >

The molded decorative article thus produced was cured at 23 ℃ under an atmosphere of 50% relative humidity for 24 hours, and then the adhesion of the decorative film to a polypropylene resin adherend was evaluated in accordance with JIS K5600-5-6. Specifically, an adhesion test was performed by a cross-hatch method in the following manner.

First, the cut was introduced from the decorative film side in a 100-grid pattern of 1mm × 1mm using a razor, and then a cellophane tape (CT 28, manufactured by ニチバン) was pressed from above with a finger to be closely attached to the decorative film, followed by peeling. In 100 cells, the case where the decorative film was not peeled off was represented by 100/100, the case where all the cells were peeled off was represented by 0/100, the cells where the decorative film was not peeled off were counted, and the adhesion of the decorative film was evaluated by the following evaluation criteria.

A：80/100～100/100

B：50/100～79/100

C：0/100～49/100

(evaluation of blocking resistance to mold)

Using the decorative films obtained in the respective examples and comparative examples, blocking resistance to a mold (adhesion to a mold) was evaluated. First, a material obtained by cutting a decorative film into a size of 25mm × 300mm was produced. The decorative film was press-bonded to an SUS304 steel plate (surface finishing BA) heated to 50 ℃ by a method according to JIS Z0237 using a 2kg roller. The adhesion was measured at a peel speed of 300 mm/min and a peel angle of 180 ° after 5 minutes from the crimping, and evaluated according to the following criteria.

A: the adhesive force is less than 0.05N/25mm

B: the adhesive force is more than 0.05N/25mm

The decorative films obtained in the examples showed good adhesion to polypropylene resin adherends. In addition, the decorative film obtained in the examples was good in blocking resistance to a mold. On the other hand, the decorative film obtained in the comparative example cannot combine good adhesion to a polypropylene resin adherend and blocking resistance to a mold.

Description of the symbols

10 substrate with decorative layer

12 adhesive layer

14 Polypropylene layer

30 decorative film

50 adherend

100 decorating the molded body.

Claims

1. A decorative film for decorating an adherend comprising a polypropylene resin, which comprises a base material having a decorative layer, an adhesive layer and a polypropylene layer in this order.

2. The decorative film according to claim 1, the adhesive layer comprising:

a terpene-based resin.

3. The decorative film according to claim 2, the terpene-based resin is at least 1 selected from the group consisting of terpene resins, aromatic modified terpene resins and terpene phenol resins,

the softening point of the terpene resin is 60 to 130 ℃,

the terpene resin has a number average molecular weight of 300 to 1500.

4. The decorative film according to claim 2 or 3, wherein the terpene-based resin is contained in an amount of 40 to 200 parts by mass based on 100 parts by mass of the block copolymer.

5. The decoration film according to any one of claims 1 to 4, wherein the thickness of the adhesive layer is 0.5 to 20 μm.

6. An ornamental film according to any one of claims 1 to 5, wherein said polypropylene layer has a thickness of 1 to 30 μm.

7. The decorative film according to any one of claims 1 to 6, which is used for decorating an adherend by film insert molding or in-mold molding.

8. A decorative molded article obtained by bonding the decorative film according to any one of claims 1 to 7 to an adherend comprising a polypropylene resin.

9. The molded decoration according to claim 8, which is used for automobile parts, electronic devices or building materials.