JP6950341B2 - A decorative film and a method for manufacturing a decorative molded product using the decorative film. - Google Patents

Description

The present invention relates to a decorative film for attaching to a resin molded body by thermoforming, and a method for producing a decorative molded body using the decorative film. Specifically, it is possible to suppress wrinkles and rupture of the film during thermoforming, to develop sufficient adhesive strength to the resin molded body, to return the grain after thermoforming, and to be contained in the film during thermoforming. The present invention relates to a decorative film for attaching to a resin molded body by thermoforming, which causes less damage to the film such as the additive migrating to the outside of the film, and a method for producing a decorative molded body using the decorative film.

In recent years, there has been an increasing demand for decoration technology that replaces painting due to VOC (volatile organic compound) reduction demands and the like, and various decoration technologies have been proposed.

Among them, a technique has been proposed in which a decorative film instead of a coating film is applied to a molded product by vacuum pressure air molding or vacuum forming to form a decorative molded product in which the decorative film and the molded product are integrated (for example, Patent Document 1). (See), in recent years, it has received particular attention.

Compared to other decorative moldings typified by insert molding, vacuum pressure air forming and decorative molding by vacuum forming have a greater degree of freedom in shape, and the end face of the decorative film is caught up to the back side of the object to be decorated, resulting in a seam. It is excellent in appearance because it does not occur, and it can be thermoformed at a relatively low temperature and low pressure. It has the advantage of being excellent in vacuum forming.

In such vacuum pressure air forming and decorative molding by vacuum forming, when the decorative film and the molded body are attached to each other, the decorative film may be broken or wrinkled, or the decorative film and the molded body may be adhered to each other. There was a problem that sufficient strength could not be obtained. In addition, the use of adhesives, tack fires, etc. has been proposed as a layer for improving the adhesive strength, but it is expensive, the layer structure becomes extremely complicated, and solvent resistance and heat resistance are insufficient. , Etc. have problems.

To solve such a problem, the decorative film and the molded body are heat-sealed by applying a decorative film containing an adhesive layer containing the polypropylene resin to a substrate (molded body) made of a polypropylene resin. (See, for example, Patent Documents 2 and 3). The inventions disclosed in Patent Documents 2 and 3 use a polypropylene resin as an adhesive layer of a decorative film, but substantially further, an acrylic is used as a surface layer, a bonding layer and a bulk layer on the adhesive layer. It is necessary to provide a layer of resin, polyurethane resin, polycarbonate or the like. By combining different kinds of raw materials in this way, thermoformability such as draw-down property is exhibited, and it is possible to ensure thermoformability in a decorative film made of polypropylene resin that does not contain these different kinds of raw materials. This was not possible, and holes, wrinkles, and air entrainment were likely to occur on the surface of the molded product to which the molded product was attached, and further, film rupture occurred, making it impossible to obtain a decorative molded product having an excellent appearance. In particular, when polyurethane resin is contained as a dissimilar raw material, polyurethane resin, which is a thermosetting resin, does not melt when heated, so that it is easy to maintain the form of the film and the thermoformability is greatly improved, but there is a problem that recyclability is extremely low. rice field.

That is, the decorative films described in Patent Documents 2 and 3 contain different raw materials in order to ensure thermoformability such as adhesiveness and appearance, have a complicated layer structure, and require many steps for their production. In addition, there is a problem that it is difficult to recycle a decorative film in which different kinds of raw materials are combined.

Further, there is a problem that a phenomenon of wrinkle return occurs in which wrinkles and the like on the film surface disappear due to heating and melting of the film during thermoforming.

Further, vacuum pressure air molding and decorative thermoforming by vacuum molding have an advantage that a molded product having a high degree of integration between the base molded in a process such as injection molding and the decorative film can be obtained, while the decorative film is the base. There is a problem that the scratches on the surface of the decorative molded product are picked up, and the appearance of the decorative molded product is likely to be poor due to the influence of the scratches on the surface of the substrate.

JP-A-2002-67137 Japanese Unexamined Patent Publication No. 2013-14027 Japanese Unexamined Patent Publication No. 2014-124940

With conventional techniques, a decorative film made of a propylene-based resin that is easy to recycle and has both adhesiveness and appearance has not yet been achieved. In view of the above problems, the subject of the present invention is that sufficient adhesive strength and product appearance can be achieved at the same time, there is little wrinkle return, and by making the scratches on the substrate inconspicuous, it is possible to reduce product defects, and further to recycle. It is an object of the present invention to provide a decorative film used for three-dimensional decorative thermoforming and a method for producing a decorative molded product using the same.

In three-dimensional decorative thermoforming, it is necessary that the surface of the molded body and the film are sufficiently softened or melted in order to attach the decorative film in the solid state to the resin molded body in the solid state. It is important to apply the amount of heat required to soften or melt the surface of the molded product and the film, or to use a molded product and film that are easily softened or melted, but if the film is heated sufficiently, the viscosity of the film will decrease. In the three-dimensional decorative thermoforming process, the film is broken or violent due to the push-up of the molded product or the inflow of air when the vacuum chamber is returned to atmospheric pressure, which leads to poor appearance. Further, if the film is heated too much, the additive contained in the film is transferred to the outside of the film, which causes a problem that the addition function derived from the additive such as heat resistance, weather resistance, and nucleation performance is deteriorated. Further, there arises a problem that grain return is likely to occur. Therefore, the researchers focused on the composition of the decorative film not only to solve these problems but also to make the scratches on the surface of the substrate inconspicuous. As a result, the seal layer (I) made of polypropylene resin (A), which can exhibit good adhesive strength by sufficiently melting and relaxing, and the viscosity of the entire film are suppressed from being lowered to maintain thermoformability and wrinkle. It has been found that the above-mentioned problems can be solved by the combination of the layer (II) made of the polypropylene-based resin (B) that suppresses the return.
Furthermore, surprisingly, such a decorative film has a high effect of making scratches inconspicuous, and it has been found that the above-mentioned problems can be solved, and the present invention has been completed.

That is, the present invention includes the following.
[1] A decorative film for being adhered onto a resin molded body by thermal molding, wherein the decorative film is a seal layer (I) made of a polypropylene-based resin (A) and a polypropylene-based resin or a polypropylene-based resin. Containing layer (II) consisting of composition (B),
The polypropylene-based resin (A) satisfies the following requirements (a1) to (a4), and the polypropylene-based resin or polypropylene-based resin composition (B) satisfies the following requirements (b1) to (b3). Decorative film to be.
(A1) The melt flow rate (230 ° C., 2.16 kg load) (MFR (A)), which is a metallocene-catalyzed propylene-based polymer, exceeds 0.5 g / 10 minutes (a3). Tm (A)) is less than 150 ° C. (a4) The molecular weight distribution (Mw / Mn (A)) obtained by GPC measurement is 1.5 to 3.5 (b1) Melt flow rate (230 ° C.). , 2.16 kg load) (MFR (B)) is 40 g / 10 minutes or less (b2) Strain hardening degree λ is 1.1 or more (b3) Melting peak temperature (Tm (B)) and Tm (A) is Tm (B)> Tm (A) ... Equation (b-3) that satisfies the relational expression (b-3).
[2] The decorative film according to [1], wherein the polypropylene-based resin (A) is a propylene / α-olefin copolymer.
[3] The decorative film according to [1] or [2], wherein Tm (A) is 140 ° C. or lower.
[4] The decorative film according to [1] to [3], wherein the polypropylene-based resin or polypropylene-based resin composition (B) satisfies the following requirements (b1') to (b2').
(B1') MFR (B) is 20 g / 10 minutes or less (b2') Strain hardening degree λ is 1.8 or more [5] The polypropylene-based resin or polypropylene-based resin composition (B) is , The decorative film according to claim 1 and 4, wherein the following requirements (b1 ") to (b2") are satisfied.
(B1 ") MFR (B) is 12 g / 10 minutes or less (b2") Strain hardening degree λ is 2.3 or more [6] The polypropylene-based resin or polypropylene-based resin composition (B) is The decorative film according to any one of [1] to [5], which comprises a polypropylene-based resin (B-1) having a long-chain branched structure.
[7] The decorative film according to [6], wherein the polypropylene-based resin (B-1) is a polypropylene-based resin produced by a method other than a cross-linking method and having a small amount of gel.
[8] The step of preparing the decorative film according to any one of [1] to [7], the step of preparing a resin molded body, and the resin molded body and the decorative film in a decompressable chamber box. A step of setting, a step of depressurizing the inside of the chamber box, a step of heating and softening the decorative film, a step of pressing the decorative film against the resin molded body, a step of returning or applying the pressure inside the decompressed chamber box to atmospheric pressure. A method for producing a decorative molded product, which comprises a step of pressing.
[9] The method for producing a decorative molded product according to [8], wherein the resin molded product uses a propylene-based resin composition as a base material.

According to the decorative film of the present invention, the three-dimensional decorative thermoformability is good, the adhesive force with the molded body is high, and the film can be attached to the molded body in a short heating time, so that the texture return is suppressed. It is possible to obtain a decorative film that is difficult to pick up scratches on the surface of the molded product and has good recyclability.

According to the method for producing a decorative molded product of the present invention, there are no holes or wrinkles on the surface, there is no air entrainment between the decorative film and the resin molded product, and the reproducibility of textures such as wrinkles is good. It is possible to obtain a beautiful decorative molded product in which scratches are inconspicuous. In addition, the decorative film can be neatly attached to the resin molded body, which has been difficult to adhere in the past. Further, in the decorative molded product thus obtained, since the constituent material of the decorative film is polypropylene-based resin (B) and does not contain or does not need to contain the thermosetting resin layer, it is necessary to contain the heat-curable resin layer at the time of recycling. There is little deterioration in appearance and performance, and it is highly suitable for recycling.

It is a figure which shows the example of the layer structure of the decorative film of this invention. It is a schematic cross-sectional view explaining the outline of the apparatus used in the manufacturing method of the decorative molded article of this invention. FIG. 5 is a schematic cross-sectional view illustrating a state in which a resin molded body and a decorative film are set in the apparatus of FIG. It is a schematic cross-sectional view explaining the state of heating and depressurizing the inside of the apparatus of FIG. FIG. 5 is a schematic cross-sectional view illustrating a state in which a decorative film is pressed against a resin molded body in the apparatus of FIG. It is a schematic cross-sectional view explaining how the inside of the apparatus of FIG. 2 returns to atmospheric pressure or pressurizes. It is a schematic cross-sectional view explaining how the edge of an unnecessary decorative film was trimmed in the obtained decorative molded body. It is a figure which shows the example of the layer structure of the obtained decorative molded article.

In the present specification, the decorative film means a film for decorating a molded product. Decorative molding refers to molding in which a decorative film and a molded body are attached to each other. The three-dimensional decorative thermoforming is a molding in which a decorative film and a molded body are bonded to each other, and has a step of thermoforming the decorative film along the bonding surface of the molded body and simultaneously bonding the decorative film. In this step, in order to prevent air from being entrained between the decorative film and the molded body, thermoforming is performed under reduced pressure (vacuum), the heated decorative film is attached to the molded body, and pressure is applied. Molding is a process of bringing the product into close contact by releasing (pressurizing) it. Hereinafter, embodiments for carrying out the present invention will be described in detail.

The decorative film in the present invention is a decorative film for being attached onto a resin molded body by thermal molding, and the decorative film is a seal layer (I) made of a polypropylene-based resin (A) and a polypropylene-based one. Containing a layer (II) composed of a resin or a polypropylene-based resin composition (B),
The polypropylene-based resin (A) satisfies the following requirements (a1) to (a4), and the polypropylene-based resin or polypropylene-based resin composition (B) satisfies the following requirements (b1) to (b3). It is a decorative film.
(A1) The melt flow rate (230 ° C., 2.16 kg load) (MFR (A)), which is a metallocene-catalyzed propylene-based polymer, exceeds 0.5 g / 10 minutes (a3). Tm (A)) is less than 150 ° C. (a4) The molecular weight distribution (Mw / Mn (A)) obtained by GPC measurement is 1.5 to 3.5 (b1) Melt flow rate (230 ° C.). , 2.16 kg load) (MFR (B)) is 40 g / 10 minutes or less (b2) Strain hardening degree λ is 1.1 or more (b3) Melting peak temperature (Tm (B)) and Tm (A) is Tm (B)> Tm (A) ... Equation (b-3) that satisfies the relational expression (b-3).

Polypropylene resin (A)
The decorative film of the present invention contains a seal layer (I) made of a polypropylene-based resin (A). The seal layer (I) is a layer that comes into contact with the resin molded body (base) during three-dimensional decorative thermoforming. The polypropylene-based resin (A) is preferably a resin that is easily melted and relaxed. By providing the seal layer (I), the occurrence of holes, wrinkles, air entrainment, etc. on the surface of the decorative molded product can be suppressed, and scratches on the surface of the substrate can be made inconspicuous.

The melt flow rate (230 ° C., 2.16 kg load) MFR (A) of the polypropylene resin (A) needs to exceed 0.5 g / 10 minutes, preferably 1 g / 10 minutes or more, more preferably. 2g / 10 minutes or more. Within the above range, relaxation during three-dimensional decorative thermoforming is sufficiently advanced, and sufficient adhesive strength can be exhibited. The upper limit of MFR (A) is not limited, but is preferably 100 g / 10 minutes or less. Within the above range, deterioration of adhesive strength due to deterioration of physical properties does not occur.

In the present specification, the MFR of the polypropylene-based resin (A) and the polypropylene-based resin composition (A) described later was measured in accordance with ISO 1133: 1997 Connections M under the conditions of 230 ° C. and a 2.16 kg load. .. The unit is g / 10 minutes.

The Mw / Mn of the polypropylene-based resin (A) is 1.5 to 3.5, preferably 2 to 3. Within the above range, there are few components having a relatively long relaxation time, and it is easy to sufficiently relax, which is preferable.
Mn and Mw are described in "Basics of Polymer Chemistry" (edited by the Society of Polymer Chemistry, Tokyo Chemistry, 1978) and are values calculated from the molecular weight distribution curve by GPC.

The melting point (DSC melting peak temperature) of the polypropylene-based resin (A) is less than 150 ° C., preferably 145 ° C. or lower, more preferably 140 ° C. or lower, still more preferably 130 ° C. or lower. Within the above range, sufficient adhesive strength can be exhibited. If Tm (A) is too low, the heat resistance is lowered and problems may occur in the use of the molded product. Therefore, the temperature is preferably 100 ° C. or higher, more preferably 110 ° C. or higher.

The polypropylene-based resin (A) of the present invention is a so-called metallocene-catalyzed propylene-based polymer that is polymerized by a metallocene catalyst. Since the metallocene catalyst has a single active point, the propylene-based polymer polymerized by the metallocene catalyst has a narrow molecular weight distribution and crystallinity distribution, and is easy to melt and relax. Can be fused with.

The polypropylene-based resin (A) in the present invention is various types of propylene-based resins such as a propylene homopolymer (homopolypropylene), a propylene-α-olefin copolymer (random polypropylene), and a propylene block copolymer (block polypropylene). Polymers or combinations thereof can be selected. The propylene-based polymer preferably contains 50 mol% or more of polymerization units derived from the propylene monomer. The propylene-based polymer preferably does not contain a polymerization unit derived from a polar group-containing monomer.

The polypropylene-based resin (A) is preferably a propylene-α-olefin copolymer from the viewpoint of sealing property, and the propylene-α-olefin copolymer usually has a lower melting point than the propylene homopolymer. Since the crystallization temperature is also lowered, the polymer is more easily deformed during thermal molding and has a high effect of making scratches inconspicuous.
As the α-olefin, one or a combination of two or more selected from ethylene and an α-olefin having 3 to 8 carbon atoms can be used.

Further, the polypropylene-based resin (A) may contain additives, fillers, other resin components, and the like. That is, it may be a resin composition (polypropylene resin composition) of a propylene-based polymer and an additive, a filler, other resin components, and the like. The total amount of additives, fillers, other resin components and the like is preferably 50% by weight or less with respect to the polypropylene-based resin composition.

When the polypropylene-based resin (A) is the polypropylene-based resin composition (A), it is preferable that the polypropylene-based resin composition has the characteristics of the polypropylene-based resin (A).

As the additive, it can be used for polypropylene-based resins such as antioxidants, neutralizers, light stabilizers, ultraviolet absorbers, crystal nucleating agents, blocking inhibitors, lubricants, antistatic agents, and metal deactivators. Various known additives can be blended.

Examples of the antioxidant include a phenol-based antioxidant, a phosphite-based antioxidant, and a thio-based antioxidant. Examples of the neutralizing agent include higher fatty acid salts such as calcium stearate and zinc stearate. Examples of the light stabilizer and the ultraviolet absorber include hindered amines, benzotriazoles, benzophenones and the like.

Examples of the crystal nucleating agent include amide-based nucleating agents such as aromatic carboxylic acid metal salts, aromatic phosphoric acid metal salts, sorbitol-based derivatives, and rosin metal salts. Among these crystal nucleating agents, pt-butyl benzoate aluminum, phosphate 2,2'-methylenebis (4,6-di-t-butylphenyl) sodium, phosphate 2,2′-methylenebis (4) , 6-di-t-butylphenyl) aluminum, bis (2,4,8,10-tetra-tert-butyl-6-hydroxy-12H-dibenzo [d, g] [1,2,3] dioxaphospho Syn-6-oxide) complex of aluminum hydroxide salt and organic compound, p-methyl-benzylene sorbitol, p-ethyl-benzylene sorbitol, 1,2,3-trideoxy-4,6: 5,7-bis- [ Examples include (4-propylphenyl) methylene] -nonitol, a sodium salt of rosin, and the like.

Examples of the lubricant include higher fatty acid amides such as stearic acid amide. Examples of the antistatic agent include fatty acid partial esters such as glycerin fatty acid monoester. Examples of the metal deactivator include triazines, phosphons, epoxies, triazoles, hydrazides, oxamides and the like.

As the filler, various known fillers that can be used for polypropylene-based resins, such as inorganic fillers and organic fillers, can be blended. Examples of the inorganic filler include calcium carbonate, silica, hydrotalcite, zeolite, aluminum silicate, magnesium silicate, glass fiber and carbon fiber. Examples of the organic filler include crosslinked rubber fine particles, thermosetting resin fine particles, and thermosetting resin hollow fine particles.

Examples of other resin components include polyethylene-based resins, polyolefins such as ethylene-based elastomers, modified polyolefins, and other thermoplastic resins.

The polypropylene-based resin composition (A) is a method of melt-kneading a propylene-based polymer with additives, fillers, other resin components, etc., and melt-kneading a propylene-based polymer with additives, fillers, etc. with other resins. It can be produced by a method of dry-blending the components, a method of dry-blending a masterbatch in which additives, fillers and the like are dispersed in a carrier resin in addition to the propylene polymer and other resin components at a high concentration.

Polypropylene resin and polypropylene resin composition (B)
By including the polypropylene-based resin or the layer (I) made of the polypropylene-based resin composition (B) in the decorative film, it is possible to suppress the occurrence of appearance defects due to the film breaking or violent during thermoforming. You can. As a result, the thermoformability of the decorative film is improved, so that it is not necessary to include a thermosetting resin layer having excellent thermoformability. The layer (II) may be made of a polypropylene-based resin (B), a polypropylene-based resin composition (B) containing a plurality of polypropylene-based resins, and other than the polypropylene-based resin (B). Polypropylene resin may be present. When the layer (II) is made of the polypropylene-based resin (B), the polypropylene-based resin (B) satisfies the requirements (b1) and (b2) described later. When the layer (II) is made of the polypropylene-based resin composition (B), the polypropylene-based resin composition (B) satisfies the requirements (b1) and (b2) described later. When another polypropylene-based resin is present in addition to the polypropylene-based resin (B), at least the polypropylene-based resin (B) is required to be added to the polypropylene-based resin composition (B) and the requirements (b1) described later. It is preferable to satisfy (b2). The blend of the polypropylene-based resin (B) and the other polypropylene-based resin is not particularly limited, and may be a mixture of pellets and / or powder, a melt blend, or a solution blend, or a combination thereof.

The strain hardening degree of the polypropylene-based resin or the polypropylene-based resin composition (B) satisfies the following requirement (b2), preferably the requirement (b2'), and more preferably the requirement (b2 ″). By setting the degree of strain curing of the resin or polypropylene-based resin composition (B) to a value in the following range, a decorative molded body having a good appearance can be obtained.
(B2) Strain hardening degree λ is 1.1 or more (b2') Strain hardening degree λ is 1.8 or more (b2 ″) Strain hardening degree λ is 2.3 or more

The upper limit of the strain curing degree of the polypropylene-based resin or the polypropylene-based resin composition (B) is not particularly limited, but is preferably 50 or less, more preferably 20 or less. By setting the degree of strain curing to a value in the above range, the appearance of the decorative film can be improved.

The degree of strain curability of the polypropylene-based resin or the polypropylene-based resin composition (B) is determined based on the measurement of strain curability in the extensional viscosity measurement. Regarding strain curability (non-linearity) of extensional viscosity, "Lecture / Rheology", edited by Society of Rheology, Japan, Polymer Publishing Association, 1992, pp. It is described in 221-222, and in the present invention, the strain hardening degree is calculated by a method according to the method shown in FIG. 7-20 of the same document, and the value of shear viscosity is η ^* (0.01). ) Is adopted as the value of the extensional viscosity, and the strain hardening degree λ is defined by the following equation (b-2).
λ = ηe (3.5) / {3 × η ^* (0.01)} Equation (b-2)
In the above formula (b-2), η ^* (0.01) is a complex viscosity coefficient [unit: Pa] at a measurement temperature of 180 ° C. and an angular frequency of ω = 0.01 rad / s, which is measured by a dynamic frequency sweep experiment. · S], and the complex viscosity η ^* is calculated from the complex elastic modulus G ^* [unit: Pa] and the angular frequency ω by η ^* = G ^* / ω. Further, ηe (3.5) is the extensional viscosity measured by measuring the extensional viscosity at a measurement temperature of 180 ° C., a strain rate of 1.0 s- ¹ , and a strain amount of 3.5.

Usually, the data obtained by these viscoelasticity measurements is a collection of numerical values such as elastic modulus and viscosity at each discrete frequency or measurement time interval. Therefore, when the measurement is carried out under a device or condition different from that used in the present invention, the complex viscosity η ^* (0.01) and the strain amount 3.5 at an angular frequency ω = 0.01 rad / s are not necessarily required. There may be cases where the data of the extensional viscosity ηe (3.5) does not exist, but in that case, the corresponding value is estimated by performing interpolation such as linear interpolation and spline interpolation using the data before and after that. Is allowed to do. When performing interpolation, it is common practice to use a logarithmic scale for the stress and time scales.

At this time, if the sample does not have strain curability (non-linearity) in extensional viscosity, the strain curability λ shows a value of about 1 (for example, 0.9 or more and less than 1.1) or smaller, and the strain curability (for example, strain curability (non-linearity)). The stronger the non-linearity), the larger the value of strain hardening degree λ.

On the other hand, even if it has strain curability, if the viscosity is too low, sufficient molding stability cannot be obtained. Therefore, the polypropylene-based resin or the polypropylene-based resin composition (B) needs to have a constant viscosity. Yes, in the present invention, MFR (230 ° C., 2.16 kg load) is defined as an index of this viscosity.

In the present invention, the MFR (230 ° C., 2.16 kg load) of the polypropylene-based resin or the polypropylene-based resin composition (B) is referred to as MFR (B). The MFR (B) satisfies the following requirement (b1), preferably the requirement (b1'), and more preferably the requirement (b1 ″). The MFR of the polypropylene resin or the polypropylene resin composition (B). By setting (B) to the following value or less, a decorative molded product having a good appearance can be obtained.
(B1) MFR (B) is 40 g / 10 minutes or less (b1') MFR (B) is 20 g / 10 minutes or less (b1 ″) MFR (B) is 12 g / 10 minutes or less

The lower limit of the MFR (B) of the polypropylene-based resin or the polypropylene-based resin composition (B) is not particularly limited, but is preferably 0.1 g / 10 minutes or more, and more preferably 0.3 g / 10 minutes or more. By setting the MFR (B) to the above value or more, the moldability at the time of manufacturing the decorative film is improved, and it is possible to suppress the occurrence of appearance defects called sharkskin and interface roughness on the film surface.

In the present invention, the MFR of the polypropylene-based resin and the polypropylene-based resin composition (B) described later was measured in accordance with ISO 1133: 1997 Connections M under the conditions of 230 ° C. and a 2.16 kg load. The unit is g / 10 minutes.

General crystalline polypropylene is a linear polymer and usually does not have strain curability. On the other hand, the polypropylene-based resin (B) used in the present invention is preferably a polypropylene-based resin (B-1) having a long-chain branched structure, and the polypropylene-based resin or the polypropylene-based resin composition (B) is used. It can exhibit strain curability.

The long-chain branched structure in the present invention refers to a branched structure consisting of a molecular chain having a carbon skeleton (main chain of branching) constituting a branch having several tens of carbon atoms and a molecular weight of several hundreds or more. This long-chain branched structure is distinguished from the short-chain branched formed by copolymerizing with an α-olefin such as 1-butene.

As a method for introducing a long-chain branched structure into a polypropylene resin, a method using high-energy ionized radiation (Japanese Patent Laid-Open No. 62-121704) and a method using an organic peroxide (Japanese Patent Laid-Open No. 2001-524565). , A method of producing a macromonomer having a terminal unsaturated bond and copolymerizing it with propylene to form a long-chain branched structure (Japanese Patent Laid-Open No. 2001-525460) can be mentioned, and any method is used. Even when it is manufactured in the above manner, the strain hardening degree of the polypropylene resin can be increased.

The polypropylene-based resin (B-1) having a long-chain branched structure is not particularly limited as long as it has a long-chain branched structure, but may be a polypropylene-based resin produced by a method other than the cross-linking method. Preferably, the one obtained by a method using a macromer copolymerization method having a comb-shaped chain structure and forming a long-chain branched structure at the time of polymerization is preferable. Examples of such a method include, for example, Japanese Patent Application Laid-Open No. 2001-525460, Japanese Patent Application Laid-Open No. 10-338717, Japanese Patent Application Laid-Open No. 2002-523575, Japanese Patent Application Laid-Open No. 2009-57542, Japanese Patent Application Laid-Open No. 05027353, Japanese Patent Application Laid-Open No. Examples thereof include the methods disclosed in Kaihei 10-338717. In particular, the macromer copolymerization method of JP-A-2009-57542 is suitable for the present invention because it can obtain a long-chain branch-containing polypropylene-based resin (B-1) without generating gel.

Having a long-chain branched structure in polypropylene is defined by a method based on the rheological properties of the resin, a method of calculating the branching index g'using the relationship between the molecular weight and the viscosity, a method ^{using 13} C-NMR, and the like. In the present invention, the long-chain branched structure is defined by the ^{branching index g'and / or 13 C-NMR as shown below.}

The branching index g'is known as a direct indicator of the long-chain branching structure. Although detailed explanation is given in "Developments in Polymer Charactization-4" (JV Dawkins ed. Applied Science Publics, 1983), the definition of the branching index g'is as follows.
Branch index g'= [η] br / [η] lin
[Η] br: Intrinsic viscosity of polymer (br) having a long-chain branched structure [η] lin: Intrinsic viscosity of linear polymer having the same molecular weight as polymer (br) As is clear from the above definition, the branching index g'is If a value smaller than 1 is taken, it is determined that a long-chain branched structure exists, and the value of the branching index g'becomes smaller as the number of long-chain branched structures increases.

The branching index g'can be obtained as a function of the absolute molecular weight Mabs by using a GPC equipped with a light scatterometer and a viscometer as a detector. Details of the method for measuring the branching index g'in the present invention are described in Japanese Patent Application Laid-Open No. 2015-40213, and are as follows.
[Measuring method]
GPC: Alliance GPCV2000 (manufactured by Waters)
Detector: Listed in connection order Multi-angle laser light scattering detector (MALLS): DAWN-E (manufactured by Waitt Technology)
Differential Refractometer (RI): Attached to GPC Viscometer: Attached to GPC Mobile phase solvent: 1,2,4-trichlorobenzene (Irganox 1076 added at a concentration of 0.5 mg / mL)
Mobile phase flow rate: 1 mL / min Column: Two GMHHR-H (S) HTs manufactured by Tosoh Co., Ltd. are connected. Sample injection part temperature: 140 ° C.
Column temperature: 140 ° C
Detector temperature: All 140 ° C
Sample concentration: 1 mg / mL
Injection volume (sample loop volume): 0.2175 mL

[analysis method]
Data processing attached to MALLS in determining the absolute molecular weight (Mabs) obtained from the multi-angle laser light scattering detector (MALLS), the squared average inertia radius (Rg), and the limit viscosity ([η]) obtained from the Viscometer. The calculation is performed using the software ASTRA (version 4.73.04) with reference to the following documents.
References:
1. 1. "Developments in Polymer Charactization-4" (JV Dawkins ed. Applied Science Publics, 1983. Chapter 1.)
2. Polymer, 45, 6495-6505 (2004)
3. 3. Macromolecules, 33, 2424-2436 (2000)
4. Macromolecules, 33, 6945-6952 (2000)

In the decorative film of the present invention, if the polypropylene-based resin or the polypropylene-based resin composition (B) contains a gel, the appearance of the film deteriorates. Therefore, the polypropylene-based resin or the polypropylene-based resin does not contain the gel. It is preferable to use the composition (B). In particular, as the polypropylene-based resin (B-1) having the above-mentioned long-chain branched structure, a macromonomer having a terminal unsaturated bond is produced using a metallocene catalyst having a specific structure, and the macromonomer is copolymerized with propylene. Those produced by using a method for forming a long-chain branched structure are preferable. In particular, it is preferable that the branching index g'at an absolute molecular weight Mabs of 1,000,000, which is described below, satisfies 0.3 or more and less than 1.0, more preferably 0.55 or more and 0.98 or less, and further preferably 0. It is 75 or more and 0.96 or less, most preferably 0.78 or more and 0.95 or less. When the branching index g'is in this range, highly crosslinked components are not formed, gel is not formed, or very little, so that the layer (I) containing the polypropylene resin (B-1) is particularly present. Does not deteriorate the appearance when forming the surface of the product.

[ ¹³ C-NMR]
¹³ C-NMR can distinguish between a short-chain branched structure and a long-chain branched structure. Macromol. Chem. Phys. 2003, vol. Detailed explanations are given in 204 and 1738, and the outline is as follows.

The propylene-based polymer having a long-chain branched structure has a specific branched structure as shown in the following structural formula (1). In the structural formula (1), C _a , C _b , and C _c indicate methylene carbon adjacent to the branched carbon, C _br indicates the methine carbon at the root of the branched chain, and P ¹ , P ² , and P ³ are. , Propylene polymer residues are shown.

The propylene-based polymer residues P ¹ , P ² , and P ³ may contain a branched carbon (C _{br ) different from the C br} described in the structural formula (1) in themselves. obtain.

Such a branched structure is ^{identified by 13} C-NMR analysis. The attribution of each peak is described in Macromolecules, Vol. 35, No. 10. The description on pages 3839-3842, 2002 can be referred to. _{That is, a total of three methylene carbons (C a} , C _b , C _c ) were observed at 43.9 to 44.1 ppm, 44.5 to 44.7 ppm, and 44.7 to 44.9 ppm, respectively. Methine carbon (C _br ) is observed at 31.5 to 31.7 ppm. The methine carbon observed at 31.5 to 31.7 ppm may be abbreviated as _{branched methine carbon (C br) below.}

It is characterized in that three methylene carbons adjacent to the branched methine carbon C _{br are observed in three non-equivalent diastereotopics.}

¹³ Such a branched chain assigned by C-NMR shows a propylene-based polymer residue having 5 or more carbon atoms branched from the main chain of the propylene-based polymer, and the branch having 4 or less carbon atoms is branched. Since it can be distinguished by the difference in the peak position of carbon, in the present invention, the presence or absence of the long-chain branched structure can be determined by confirming the peak of this branched methine carbon.
^{The 13} C-NMR measurement method in the present invention is as follows.

[ ¹³ C-NMR measurement method]
An NMR sample having an inner diameter of 10 mmφ with 200 mg of a sample together with o-dichlorobenzene / benzene deuterated bromide (C ₆ D ₅ Br) = 4/1 (volume ratio) 2.4 ml and hexamethyldisiloxane, which is a reference substance for chemical shift. It was placed in a tube and dissolved, and ¹³ C-NMR measurement was performed.
¹³ C-NMR measurement was performed using an AV400M type NMR apparatus of Bruker Biospin Co., Ltd. equipped with a cryoprobe having a diameter of 10 mm.
The measurement was carried out at a sample temperature of 120 ° C. by the proton complete decoupling method. Other conditions are as follows.
Pulse angle: 90 °
Pulse interval: 4 seconds Accumulation number: 20000 times The chemical shift was set with the methyl carbon peak of hexamethyldisiloxane set to 1.98 ppm, and the chemical shift of peaks with other carbons was based on this.
The amount of long chain branching can be calculated using the peak around 44 ppm.

^{In the 13} C-NMR spectrum of the polypropylene resin (B-1) having a long-chain branched structure, the amount of long-chain branched quantified from the peak near 44 ppm is preferably 0.01 / 1000 total propylene or more. It is more preferably 0.03 pieces / 1000 total propylene or more, and further preferably 0.05 pieces / 1000 total propylene or more. If this value is too large, it may cause poor appearance of gels, fish eyes, etc. Therefore, it is preferably 1.00 pieces / 1000 total propylene or less, more preferably 0.50 pieces / 1000 total propylene, and further preferably 0. 30 pieces / 1000 total propylene or less.

The polypropylene-based resin (B-1) having such a long-chain branched structure may be contained in the polypropylene-based resin composition (B) in an amount sufficient to impart strain curability. The polypropylene-based resin (B-1) is preferably contained in an amount of 1 to 100% by weight, more preferably 5% by weight or more, based on 100% by weight of the polypropylene-based resin composition (B).

The polypropylene-based resin (B-1) in the present invention is of various types such as a propylene homopolymer (homopolypropylene), a propylene-α-olefin copolymer (random polypropylene), and a propylene block copolymer (block polypropylene). A propylene-based polymer or a combination thereof can be selected. The propylene-based polymer preferably contains 50 mol% or more of the propylene monomer.

The melting peak temperature (Tm (B)) in the DSC measurement of the polypropylene-based resin or the polypropylene-based resin composition (B) needs to be higher than Tm (A), and Tm (B)> Tm (A). .. Within the above range, the thermoformability becomes good.
The melting point (DSC melting peak temperature) of the polypropylene-based resin or the polypropylene-based resin composition (B) is preferably 140 ° C. or higher, more preferably 145 to 170 ° C., and even more preferably 150 to 168 ° C. The polypropylene-based resin (B) is preferably a propylene homopolymer or a propylene-α-olefin copolymer having such a melting point. Further, even if the melting point is high, if a low crystallinity component is contained, the scratch resistance and the solvent resistance are lowered. Therefore, the polypropylene-based resin or the polypropylene-based resin composition (B) has an ethylene content of 50 to 70% by weight. It is preferable that the ethylene-α-olefin copolymer of the above is not contained.

The polypropylene-based resin composition (B) contains a plurality of polypropylene-based resins other than the polypropylene-based resin (B-1) having a long-chain branched structure, additives, fillers, colorants, and other resin components. May be. At this time, the total amount of additives, fillers, colorants, other resin components and the like is preferably 50% by weight or less with respect to the polypropylene-based resin composition containing them.

When the decorative molded product of the present invention is molded as a colored molded product, a colorant needs to be used only on the decorative film, so that an expensive colorant is used as compared with the case where the entire resin molded product is colored. It is possible to suppress. In addition, changes in physical properties associated with the addition of a colorant can be suppressed.

As the additive, it can be used for polypropylene-based resins such as antioxidants, neutralizers, light stabilizers, ultraviolet absorbers, crystal nucleating agents, blocking inhibitors, lubricants, antistatic agents, and metal deactivators. Various known additives can be blended.

Examples of the antioxidant include a phenol-based antioxidant, a phosphite-based antioxidant, and a thio-based antioxidant. Examples of the neutralizing agent include higher fatty acid salts such as calcium stearate and zinc stearate. Examples of the light stabilizer and the ultraviolet absorber include hindered amines, benzotriazoles, benzophenones and the like.

Examples of the crystal nucleating agent include amide-based nucleating agents such as aromatic carboxylic acid metal salts, aromatic phosphoric acid metal salts, sorbitol-based derivatives, and rosin metal salts. Among these crystal nucleating agents, pt-butyl benzoate aluminum, phosphate 2,2'-methylenebis (4,6-di-t-butylphenyl) sodium, phosphate 2,2′-methylenebis (4) , 6-di-t-butylphenyl) aluminum, bis (2,4,8,10-tetra-tert-butyl-6-hydroxy-12H-dibenzo [d, g] [1,2,3] dioxaphospho Syn-6-oxide) complex of aluminum hydroxide salt and organic compound, p-methyl-benzylene sorbitol, p-ethyl-benzylene sorbitol, 1,2,3-trideoxy-4,6: 5,7-bis- [ Examples include (4-propylphenyl) methylene] -nonitol, a sodium salt of rosin, and the like.

Examples of the lubricant include higher fatty acid amides such as stearic acid amide. Examples of the antistatic agent include fatty acid partial esters such as glycerin fatty acid monoester. Examples of the metal deactivator include triazines, phosphons, epoxies, triazoles, hydrazides, oxamides and the like.

As the filler, various known fillers that can be used for polypropylene-based resins, such as inorganic fillers and organic fillers, can be blended. Examples of the inorganic filler include calcium carbonate, silica, hydrotalcite, zeolite, aluminum silicate, magnesium silicate, glass fiber, carbon fiber and the like. Further, examples of the organic filler include crosslinked rubber fine particles, thermosetting resin fine particles, and thermosetting resin hollow fine particles.

Examples of other resin components include polyethylene-based resins, polyolefins such as ethylene-based elastomers, modified polyolefins, and other thermoplastic resins.

It is also possible to color the product in order to impart designability, and various colorants such as inorganic pigments, organic pigments, and dyes can be used for coloring. It is also possible to use bright materials such as aluminum flakes, titanium oxide flakes, and (synthetic) mica.

The polypropylene-based resin composition is prepared by a method of melt-kneading a propylene-based polymer with additives, fillers, other resin components, etc., and a method of melt-kneading a propylene-based polymer with additives, fillers, etc., and drying the other resin components. It can be produced by a method of blending, a method of dry blending a masterbatch in which additives, fillers and the like are dispersed in a carrier resin in addition to a propylene polymer and other resin components at a high concentration.

Decorative film The decorative film in the present invention includes a seal layer (I) made of a polypropylene resin (A) and a layer (II) made of a polypropylene resin or a polypropylene resin composition (B). The decorative film can have various configurations in addition to the seal layer (I) and the layer (II). That is, the decorative film is a two-layer film composed of the seal layer (I) and the layer (II), but is a multilayer film having three or more layers composed of the seal layer (I) and the layer (II) and another layer. There may be. The seal layer (I) is attached along the resin molded body (base). Further, the surface of the decorative film may be textured, embossed, printed, sandplasted, scratched or the like.

The decorative film has a large degree of freedom in shape, and the end face of the decorative film is caught up to the back side of the object to be decorated, so that no seam is formed, so that the appearance is excellent. You can express various textures with. For example, when giving a texture such as embossing to a resin molded body, three-dimensional decorative thermoforming may be performed using an embossed decorative film. For this reason, there are problems in molding with a molded body mold to be embossed, that is, a molded body mold is required for each embossing pattern, and it is very difficult and expensive to apply complicated embossing to a curved mold. It is possible to solve the problem of being, and to obtain a decorative molded body easily embossed with various patterns.

In addition to the seal layer (I) and the layer (II), the multilayer film can be provided with a surface layer, a surface decoration layer, a printing layer, a light-shielding layer, a coloring layer, a base material layer, a barrier layer, and layers thereof. A tie layer layer and the like can be included. The layer (II) made of the polypropylene-based resin (B) may be any layer other than the seal layer among the layers constituting the multilayer film.

In the multilayer film, the layers other than the seal layer (I) and the layer (II) are preferably a layer made of a thermoplastic resin, and more preferably a layer made of a polypropylene resin. As long as the layers other than the seal layer (I) and the layer (II) can be distinguished from the seal layer (I) and the layer (II), the constituent polypropylene resin MFR (230 ° C., 2.16 kg load) There are no particular restrictions. Each layer is preferably a layer that does not contain a thermosetting resin. By using the thermoplastic resin, the recyclability is improved, and by using the polypropylene-based resin, the complexity of the layer structure can be suppressed, and the recyclability is further improved.

When the decorative film is a two-layer film, the sealing layer (I) made of the polypropylene-based resin (A) constitutes the sealing layer of the surface to be attached to the resin molded body, and the polypropylene-based resin or the polypropylene-based resin composition. The layer (II) made of (B) constitutes a surface layer opposite to the surface to be attached to the resin molded body.

When the decorative film is a multilayer film having three or more layers, it is between the seal layer (I) made of the polypropylene resin (A) and the layer (II) made of the polypropylene resin or the polypropylene resin composition (B). If other layers are present, the effect of suppressing the appearance of scratches on the surface of the substrate may be reduced. Therefore, the multilayer film is a seal layer (I) made of polypropylene-based resin (A) / a layer (II) made of polypropylene-based resin or polypropylene-based resin composition (B) from the sticking surface side of the resin molded product / and others. Layer (including a plurality of layers) is preferable.

1 (a) to 1 (c) are explanatory views schematically illustrating a cross section of an embodiment of a decorative film, and FIGS. 8 (a) to 8 (c) are decorations attached to a resin molded body. It is explanatory drawing which schematically exemplifies the cross section of the embodiment of a film. An embodiment of the decorative film will be described with reference to FIG. In FIGS. 8 (a) to 8 (c), the arrangement of the seal layer (I) and the layer (II) will be specified and described for ease of understanding, but the layer structure of the decorative film is limited to these examples. It is not interpreted as. In the present specification, reference numeral 1 in the drawing is a decorative film, reference numeral 2 is a layer (II), reference numeral 3 is a seal layer (I), reference numeral 4 is a surface decoration layer (III), and reference numeral 5 is a resin molded body. .. FIG. 8A shows an example in which the decorative film is made of a two-layer film, and the seal layer (I) made of polypropylene-based resin (A) is attached to the resin molded body 5 and is placed on the seal layer (I). A layer (II) made of a polypropylene-based resin or a polypropylene-based resin composition (B) is laminated on the surface. The decorative film of FIG. 8B is composed of a seal layer (I), a layer (II) and a surface layer, and the seal layer (I) is attached to the surface of the resin molded body 5 and is placed on the seal layer (I). The layer (II) and the surface layer are laminated in this order. The decorative film of FIG. 8C is composed of a surface decorative layer (III) composed of a sealing layer (I), a layer (II) and a polypropylene-based resin (C), and a sealing layer (I) is formed on the surface of the resin molded body 5. ) Is attached, and the layer (II) and the surface decoration layer (III) are laminated in this order on the seal layer (I).

Another preferred embodiment of the decorative film is a multilayer film containing a surface decorative layer (III) made of a surface decorative layer resin on the outermost surface opposite to the surface to be attached to the resin molded body. The surface decorative layer resin is preferably a thermoplastic resin, more preferably a polypropylene-based resin (C).

The melt flow rate (230 ° C., 2.16 kg load) (MFR (C)) of the polypropylene-based resin (C) in the present invention preferably satisfies MFR (C)> MFR (B). By setting the value in the above range, a more beautiful surface texture can be expressed.

The polypropylene-based resin (C) in the present invention is various types of propylene-based resins such as a propylene homopolymer (homopolypropylene), a propylene-α-olefin copolymer (random polypropylene), and a propylene block copolymer (block polypropylene). Polymers or combinations thereof can be selected. The propylene-based polymer preferably contains 50 mol% or more of polymerization units derived from the propylene monomer. The propylene-based polymer preferably does not contain a polymerization unit derived from a polar group-containing monomer. The polypropylene-based resin (C) is preferably homopolypropylene from the viewpoint of oil resistance, solvent resistance, scratch resistance and the like. Further, from the viewpoint of gloss and transparency (color development), a propylene-α-olefin copolymer is preferable. In the present invention, the polypropylene-based resin (C) constituting the surface decorative layer (III) may be the same as or different from the polypropylene-based resin (A) constituting the seal layer (I).

The polypropylene-based resin (C) may contain additives, fillers, other resin components, and the like. That is, it may be a resin composition (polypropylene resin composition) of a propylene-based polymer and an additive, a filler, other resin components, and the like. The total amount of additives, fillers, other resin components and the like is preferably 50% by weight or less with respect to the polypropylene-based resin composition.

As the additive, an additive or the like that may be contained in the polypropylene-based resin (A) can be used.

The polypropylene-based resin composition is prepared by a method of melt-kneading a propylene-based polymer with additives, fillers, other resin components, etc., and a method of melt-kneading a propylene-based polymer with additives, fillers, etc., and drying the other resin components. It can be produced by a method of blending, a method of dry blending a masterbatch in which additives, fillers and the like are dispersed in a carrier resin in addition to a propylene polymer and other resin components at a high concentration.

When the propylene-based resin (C) constituting the surface decorative layer (III) is a polypropylene-based resin composition, this polypropylene-based resin composition comprises the propylene-based resin (A) constituting the seal layer (I). It may be the same as or different from the polypropylene-based resin composition to be used.

The decorative film of the present invention has a thickness of preferably about 20 μm or more, more preferably about 50 μm or more, still more preferably about 80 μm or more. By increasing the thickness of the decorative film to such a value or more, the effect of imparting designability is improved, the stability during molding is also improved, and a better decorative molded body can be obtained. On the other hand, the thickness of the decorative film is preferably about 2 mm or less, more preferably about 1.2 mm or less, still more preferably about 0.8 mm or less. By reducing the thickness of the decorative film to such a value or less, the time required for heating during thermoforming is shortened, the productivity is improved, and it becomes easy to trim unnecessary parts.

In the decorative film of the present invention, the ratio of the thickness of the seal layer (I) to the total thickness of the decorative film is preferably 1 to 70%, and the ratio of the thickness of the layer (II) is preferably 30 to 30 to 70%. It is 99%. If the ratio of the thickness of the seal layer (I) to the entire decorative film is within the above value range, sufficient adhesive strength can be exhibited and scratches on the resin molded body (base) are exposed on the surface. Can be suppressed. Further, if the ratio of the thickness of the layer (II) to the entire decorative film is within the above value range, it is possible to avoid insufficient thermoformability of the decorative film.

Further, in the multilayer film in which the surface decorative layer (III) made of polypropylene resin (C) is provided on the outermost surface of the decorative film, the decorative film having the thickness of the surface decorative layer (III) in the decorative film. The ratio to the total thickness is preferably 30% or less.

Production of Decorative Film The decorative film of the present invention can be produced by various known molding methods. For example, a method of coextruding a seal layer (I) made of a polypropylene resin (A) and a layer (II) made of a polypropylene resin or a polypropylene resin composition (B), a seal layer (I) and a layer (II). ) And another layer are co-extruded, a thermal lamination method in which the other layer is laminated by applying heat and pressure on one surface of one pre-extruded layer, via an adhesive. Examples thereof include a dry lamination method and a wet lamination method for laminating, an extrusion lamination method and a sand lamination method in which a polypropylene-based resin is melt-extruded onto one surface of one layer extruded in advance. As an apparatus for forming the decorative film, a known coextrusion T-die molding machine or a known laminating molding machine can be used. Among these, a coextrusion T-die molding machine is preferably used from the viewpoint of productivity.

As a method of cooling the molten decorative film extruded from the die, a method of bringing the molten decorative film into contact with one cooling roll through the air discharged from the air knife unit or the air chamber unit, or Examples thereof include a method of crimping with a plurality of cooling rolls to cool the film.

In order to impart gloss to the decorative film of the present invention, a method of surface-transferring a mirror-shaped cooling roll to the design surface of the product to perform mirror surface processing is used.

Further, the surface of the decorative film of the present invention may have a textured shape. Such a decorative film is a method in which a molten resin extruded from a die is directly pressure-bonded between a roll having an uneven shape and a smooth roll to transfer the uneven shape to a surface. It can be produced by a method of surface transfer by pressure contacting a heated roll and a smooth cooling roll. Examples of the grain shape include satin finish, animal skin tone, hairline tone, carbon tone and the like.

The decorative film of the present invention may be heat-treated after the film is formed. Examples of the heat treatment method include a method of heating with a heat roll, a method of heating with a heating furnace or a far-infrared heater, a method of blowing hot air, and the like.

Decorative molded article As the molded article (object to be decorated) to be decorated in the present invention, various molded articles (hereinafter, may be referred to as "base") preferably made of polypropylene-based resin or polypropylene-based resin composition. Can be used. The molding method of the molded body is not particularly limited, and examples thereof include injection molding, blow molding, press molding, extrusion molding and the like.

Since the polypropylene-based resin is non-polar, it is a poorly adhesive polymer. However, the decorative film in the present invention has a seal layer (I) made of the polypropylene-based resin (A) and a polypropylene-based resin or a polypropylene-based resin. By including the layer (II) made of the composition (B), a decorative object made of a polypropylene resin and a decorative film are adhered to each other to exhibit extremely high adhesive strength, and on the surface of the decorative object. It is possible to make the scratches on the surface less noticeable.

As the base resin of the polypropylene-based resin and the polypropylene-based resin composition, various known propylene monomers such as a propylene homopolymer (homopolypropylene), a propylene-α-olefin copolymer, or a propylene block copolymer are mainly used. Various types of raw materials can be selected. Further, as long as the effect of the present invention is not impaired, a filler such as talc may be contained for imparting rigidity, and an elastomer or the like may be contained for imparting impact resistance. Further, the additive component and other resin components may be contained in the same manner as the polypropylene-based resin composition that can form the decorative film described above.

In the decorative molded body in which the decorative film of the present invention is attached to various molded bodies formed of polypropylene-based resin in a three-dimensional shape, VOC contained in coating or adhesive is greatly reduced. It can be suitably used as home appliances, vehicles (railroads, etc.), building materials, daily necessities, etc.

In the method for producing a decorative molded body of the present invention, the resin molded body and the decorative film are set in a step of preparing the above-mentioned decorative film, a step of preparing a resin molded body, and a chamber box capable of reducing pressure. A step, a step of depressurizing the inside of the chamber box, a step of heating and softening the decorative film, a step of pressing the decorative film against the resin molded body, and a step of returning or pressurizing the inside of the depressurized chamber box to atmospheric pressure. It is characterized by including.

In three-dimensional decorative thermoforming, a decorative object and a decorative film are set in a chamber box that can be depressurized, the film is heated and softened while the inside of the chamber box is depressurized, and the film is pressed against the decorative object. It has a basic process of attaching the decorative film to the surface of the object to be decorated by returning the inside of the chamber box to atmospheric pressure or pressurizing the inside of the chamber box, and the film is attached under reduced pressure. As a result, it is possible to obtain a clean decorative molded product that does not generate air pools. In the production method of the present invention, any known technique can be used as long as the apparatus and conditions are suitable for three-dimensional decorative thermoforming.

That is, the chamber box may contain all of the decoration object, the decoration film, the mechanism for pressing the decoration film, the device for heating the decoration film, and the like, or depending on the decoration film. It may be a plurality of divided ones.

Further, the mechanism for pressing the decoration target and the decoration film may be any type of a mechanism for moving the decoration target, a mechanism for moving the decoration film, and a mechanism for moving both of them.
More specifically, a typical molding method is illustrated below.

Hereinafter, a method of attaching a decorative film to a decorative object by using a three-dimensional decorative thermoforming machine will be exemplified with reference to the drawings.

As shown in FIG. 2, the three-dimensional decorative thermoforming machine of this embodiment includes chamber boxes 11 and 12 at the top and bottom, and thermoforms the decorative film 1 in the two chamber boxes 11 and 12. I am trying to do it. A vacuum circuit (not shown) and an air circuit (not shown) are piped to the upper and lower chamber boxes 11 and 12, respectively.

Further, a jig 13 for fixing the decorative film 1 is provided between the upper and lower chamber boxes 11 and 12. Further, a table 14 capable of ascending / descending is installed in the lower chamber box 12, and the resin molded body (decoration target) 5 is set on the table 14 (via a jig or the like or directly). NS. A heater 15 is incorporated in the upper chamber box 11, and the decorative film 1 is heated by the heater 15. The decoration target 5 can use a propylene-based resin composition as a substrate.

As such a three-dimensional decorative thermoforming machine, a commercially available molding machine (for example, NGF series manufactured by Fuse Vacuum Co., Ltd.) can be used.

As shown in FIG. 3, first, with the upper and lower chamber boxes 11 and 12 open, the decoration target 5 is placed on the table 14 in the lower chamber box 12, and the table 14 is lowered. Subsequently, the decorative film 1 is set on the film fixing jig 13 between the upper and lower chamber boxes 11 and 12 so that the seal layer (I) faces the substrate.

As shown in FIG. 4, the upper chamber box 11 is lowered, the upper and lower chamber boxes 11 and 12 are joined to close the inside of the box, and then the insides of the respective chamber boxes 11 and 12 are put into a vacuum suction state, and the heater 15 is used. The decorative film 1 is heated by the above method.

After the decorative film 1 is heated and softened, as shown in FIG. 5, the table 14 in the lower chamber box 12 is raised while the upper and lower chamber boxes 11 and 12 are in a vacuum suction state. The decorative film 1 is pressed against the decorative object 5 to cover the decorative object 5. Further, as shown in FIG. 6, by opening the upper chamber box 11 under atmospheric pressure or supplying compressed air from the air pressure tank, the decorative film 1 is brought into close contact with the decorative object 5 with a larger force.

Subsequently, the insides of the upper and lower chamber boxes 11 and 12 are opened under atmospheric pressure, and the decorative molded body 6 is taken out from the lower chamber box 12. Finally, as illustrated in FIG. 7, the edges of the unnecessary decorative film 1 around the decorative molded body 6 are trimmed.

Molding conditions The depressurization in the chamber boxes 11 and 12 may be such that no air pool is generated, and the pressure in the chamber box is 10 KPa or less, preferably 3 KPa, more preferably 1 KPa or less.

Further, in the two chamber boxes 11 and 12 divided into upper and lower parts by the decorative film 1, the pressure inside the chamber box on the side where the decorative object 5 and the decorative film 1 are attached may be within this range, and the upper and lower chamber boxes may be up and down. The drawdown of the decorative film 1 can be suppressed by changing the pressures of the chamber boxes 11 and 12 of the above.

At this time, a film made of a general polypropylene resin may be significantly deformed and ruptured by a slight pressure fluctuation due to a decrease in viscosity during heating.

The decorative film 1 of the present invention is not only difficult to draw down, but also resistant to film deformation due to pressure fluctuations.

The heating of the decorative film 1 is controlled by the heater temperature (output) and the heating time. It is also possible to measure the surface temperature of the film with a thermometer such as a radiation thermometer and use it as a guideline for appropriate conditions.

In the present invention, in order to attach the polypropylene-based decorative film 1 to the decorative object 5 made of polypropylene-based resin, it is necessary that the surface of the resin molded body 5 and the decorative film 1 are sufficiently softened or melted.

Therefore, the heater temperature needs to be higher than the melting temperature of the polypropylene-based resin constituting the decoration target 5 and the polypropylene-based resin constituting the decoration film 1. The heater temperature is preferably 160 ° C. or higher, more preferably 180 ° C. or higher, and most preferably 200 ° C. or higher.

The higher the heater temperature, the shorter the time required for heating, but the heater side is sufficiently heated until the inside of the decorative film 1 (or the surface opposite to the heater when the heater is installed on only one side) is sufficiently heated. The heater temperature is preferably 500 ° C. or lower, more preferably 450 ° C. or lower, and most preferably 400 ° C. It is as follows.

The appropriate heating time varies depending on the heater temperature, but it is preferably 2 seconds or more after the polypropylene-based decorative film is heated and the tensioning back called springback is completed.

That is, the decorative film heated by the heater expands thermally when heated from the solid state and sags once as the crystal melts, and when the crystal melt progresses, the molecules relax and the springback temporarily rebounds. Is observed, and then it hangs down due to its own weight, but after springback, the crystals of the film are completely melted and the molecules are sufficiently relaxed, so that sufficient adhesive strength can be obtained.

On the other hand, if the heating time is too long, the film may hang down due to its own weight or may be deformed due to the pressure difference between the upper and lower chamber boxes. Therefore, the heating time is preferably less than 120 seconds after the end of springback.

When decorating a molded product having an uneven shape or achieving higher adhesive strength, it is preferable to supply compressed air when the decorative film is brought into close contact with the substrate. The pressure in the upper chamber box when compressed air is introduced is 150 kPa or more, preferably 200 kPa or more, and more preferably 250 kPa or more. The upper limit is not particularly limited, but if the pressure is too high, the equipment may be damaged. Therefore, 450 kPa or less, preferably 400 kPa or less is preferable.

Hereinafter, the present invention will be described in more detail as examples, but the present invention is not limited to this example.

1. 1. Measurement method of various physical properties (i) MFR
Measured at 230 ° C. with a 2.16 kg load according to ISO 1133: 1997 Connections M. The unit is g / 10 minutes.

(Ii) Melting point:
Using a differential scanning calorimeter (DSC), once the temperature was raised to 200 ° C. and held for 10 minutes, the temperature was lowered to 40 ° C. at a temperature lowering rate of 10 ° C./min, and then again at a heating rate of 10 ° C./min. The temperature at the top of the endothermic peak at the time of measurement was taken as the melting point. The unit is ° C.

(Iii) GPC measurement GPC measurement was performed under the following equipment and conditions, and Mw / Mn was calculated.
-Device: Waters GPC (ALC / GPC 150C)
-Detector: MIRAN 1A IR detector manufactured by FOXBORO (measurement wavelength: 3.42 μm)
-Column: Showa Denko AD806M / S (3)
-Mobile phase solvent: orthodichlorobenzene (ODCB)
-Measurement temperature: 140 ° C
-Flow velocity: 1.0 ml / min
・ Injection amount: 0.2 ml
-Sample preparation: For the sample, prepare a 1 mg / mL solution using ODCB (containing 0.5 mg / mL BHT) and dissolve it at 140 ° C. for about 1 hour.

The conversion from the retention capacity obtained by GPC measurement to the molecular weight is performed using a calibration curve prepared in advance using standard polystyrene (PS). The standard polystyrenes used are all the following brands manufactured by Tosoh Corporation.
F380, F288, F128, F80, F40, F20, F10, F4, F1, A5000, A2500, A1000
A calibration curve is created by injecting 0.2 mL of solution dissolved in ODCB (containing 0.5 mg / mL BHT) so that each is 0.5 mg / mL. The calibration curve uses a cubic equation obtained by approximating with the least squares method.
The following numerical values are used for the viscosity formula [η] = K × Mα used for conversion to the molecular weight.
PS: K = 1.38 × 10 ^-4 , α = 0.7
PP: K = 1.03 × 10 ^-4 , α = 0.78

2. Materials used (1) Polypropylene resin The following polypropylene resin was used.
(A-1): Metallocene-catalyzed propylene-α-olefin copolymer (MFR = 7 g / 10 minutes, Tm = 125 ° C., Mw / Mn = 2.5), manufactured by Japan Polypropylene Corporation, trade name " Wintech (registered trademark) WFX4M "
(A-2): Metallocene-catalyzed propylene-α-olefin copolymer (MFR = 25 g / 10 minutes, Tm = 125 ° C., Mw / Mn = 2.4), manufactured by Japan Polypropylene Corporation, trade name " Wintech (registered trademark) WSX03 "
(A-3): Metallocene-catalyzed propylene-α-olefin copolymer (MFR = 7 g / 10 minutes, Tm = 135 ° C., Mw / Mn = 2.3), manufactured by Japan Polypropylene Corporation, trade name " Wintech (registered trademark) WFW4M "
(A-4): Metallocene-catalyzed propylene-α-olefin copolymer (MFR = 3.5 g / 10 minutes, Tm = 143 ° C., Mw / Mn = 2.8), manufactured by Japan Polypropylene Corporation, commercial product Name "Wintech (registered trademark) WFW5T"
(A-5): Ziegler-Natta-catalyzed propylene-α-olefin copolymer (MFR = 7 g / 10 minutes, Tm = 145 ° C., Mw / Mn = 4.0), manufactured by Japan Polypropylene Corporation, product Name "Novatec (registered trademark) FW3GT"
(B-1-1): A propylene homopolymer having a long chain branch produced by the macromer copolymerization method (MFR = 1 g / 10 minutes, Tm = 154 ° C.), manufactured by Japan Polypropylene Corporation, trade name "WAYMAX". (Registered trademark) MFX8 "
(B-1-2): A propylene homopolymer having a long chain branch produced by the macromer copolymerization method (MFR = 8.8 g / 10 minutes, Tm = 154 ° C.), manufactured by Japan Polypropylene Corporation, trade name. "WAYMAX (registered trademark) MFX3"
(B-1-3): A polypropylene resin composition obtained by blending 96% by weight of a polypropylene resin (B-1-1) with 4% by weight of a black pigment MB (EPP-K-12601 manufactured by Polycol Kogyo Co., Ltd.). MFR = 1.0 g / 10 minutes, strain hardening degree λ = 9.3, Tm = 154 ° C)
(B-2-1): Normal (without long-chain branching) propylene homopolymer (MFR = 10 g / 10 minutes, Tm = 161 ° C), manufactured by Japan Polypropylene Corporation, trade name "Novatec (registered) Trademark) FA3KM "
(B-2-2): Normal (without long-chain branching) propylene homopolymer (MFR = 2.4 g / 10 minutes, Tm = 161 ° C), manufactured by Japan Polypropylene Corporation, trade name "Novatec" (Registered trademark) FY6 "
(C-1): A polypropylene resin blended with 100 parts by weight of a polypropylene resin (B-2-1) by 0.4 parts by weight of a nucleating agent (manufactured by Milliken Japan Co., Ltd., trade name "Milllad NX8000J"). Composition (MFR = 10 g / 10 minutes, Tm = 164 ° C)
(C-2): Polypropylene resin composition blended with 100 parts by weight of polypropylene resin (A-1) by 0.4 parts by weight of a nucleating agent (manufactured by Milliken Japan Co., Ltd., trade name "Milllad NX8000J"). (MFR = 7 g / 10 minutes, Tm = 127 ° C)
(C-3): Polypropylene resin (B-2-1) 96% by weight, MFR = 11 g / 10 minutes white pigment MB (EPP-W-59578 manufactured by Polycol Kogyo Co., Ltd., titanium oxide content 80% by weight) ) Is blended in an amount of 4% by weight (MFR = 10 g / 10 minutes, Tm = 161 ° C.).
(C-4): Polypropylene resin composition (MFR = 10 g) in which 96% by weight of polypropylene resin (B-2-1) is blended with 4% by weight of silver pigment MB (PPCM913Y-42 SILVER21X manufactured by Toyo Color Co., Ltd.). / 10 minutes, Tm = 161 ° C)

3. 3. Production of Resin Molded Body (Base) An injection molded product was obtained by the following method using the following polypropylene-based resins (X-1) to (X-3).
(X-1): Propylene homopolymer (MFR = 40 g / 10 minutes, Tm = 165 ° C.), manufactured by Japan Polypropylene Corporation, trade name "Novatec (registered trademark) MA04H"
(X-2): Propylene ethylene block copolymer (MFR = 30 g / 10 minutes, Tm = 164 ° C.), manufactured by Japan Polypropylene Corporation, trade name "Novatec (registered trademark) NBC03HR"
(X-3): 60% by weight of polypropylene resin (X-2), 20% by weight of EBR (Toughmer (registered trademark) A0550S manufactured by Mitsui Chemicals, Inc.) with MFR = 1.0, inorganic filler (Nippon Tarku) Talk P-6 manufactured by TARC Co., Ltd., average particle size 4.0 μm) 20% by weight blended polypropylene resin composition Injection molding machine: "IS100GN" manufactured by Toshiba Machine Co., Ltd., mold clamping pressure 100 tons Cylinder temperature: 200 ° C.
Mold temperature: 40 ° C
Injection mold: Width x Height x Thickness = 120 mm x 120 mm x 3 mm Flat plate Condition adjustment: Hold for 5 days in a constant temperature and humidity chamber with a temperature of 23 ° C and a humidity of 50% RH

Further, the obtained injection molded product was scratched by the following method to obtain a resin molded product (base).
Scratch evaluation processing: Using a scratch tester (ROCKWOOD SYSTEMS AND EQUIPMENT "SCRATCH & MAR TESTER") in a constant temperature and humidity chamber with a temperature of 23 ° C and a humidity of 50% RH, the shape (radius of curvature 0. The injection molded body was scratched by scratching at a scratching speed of 100 mm / min with a scratched tip that had been processed (5 mm, ball-shaped).

When the scratches on the surface of the resin molded body (base) were measured with a shape measuring instrument laser microscope (“VX-X200” manufactured by KEYENCE), the depth of the scratches was 13 μm. In addition, the scratch was a whitening scratch.

(Example 1)
-Manufacture of decorative film Two types of two layers with a lip opening of 0.8 mm and a die width of 400 mm, to which an extruder-1 for a seal layer with a diameter of 30 mm (diameter) and an extruder-2 with a diameter of 40 mm (diameter) are connected. A T-die was used. A polypropylene resin (A-1) is charged into the seal layer extruder-1, and a polypropylene resin (B-1-1) is charged into the extruder-2. The resin temperature is 240 ° C., and the seal layer extruder-1 is used. The melt extrusion was performed under the conditions that the discharge rate of the extruder was 4 kg / h and the discharge rate of the extruder-2 was 12 kg / h. The melt-extruded film was cooled and solidified while being pressed with an air knife against a first roll rotated at 3 m / min at 80 ° C. so that the seal layer was on the outside, and the seal layer (I) having a thickness of 50 μm and a thickness of 150 μm were obtained. A two-layer unstretched film in which the layer (II) of No. 1 was laminated was obtained.

-As the three-dimensional decorative thermoformed resin molded body (base) 5, an injection molded body made of the polypropylene-based resin (X-1) obtained above was used.
As a three-dimensional decorative thermoforming apparatus, "NGF-0406-SW" manufactured by Fuse Vacuum Co., Ltd. was used. As shown in FIGS. 2 to 7, the decorative film 1 is cut out with a width of 250 mm and a length of 350 mm so that the seal layer faces the substrate and the longitudinal direction is the MD direction of the film, and the size of the opening is 210 mm. It was set on a film fixing jig 13 of × 300 mm. The resin molded body (base) 5 is placed on a sample setting table having a height of 20 mm, which is installed on a table 14 located below the film fixing jig 13, and is manufactured by Nichiban Co., Ltd. “Nystack NW-K15”. I pasted it through. The film fixing jig 13 and the table 14 were installed in the chambers 11 and 12, and the chamber was closed to seal the chamber boxes 11 and 12. The chamber box is divided into upper and lower parts via a decorative film 1. With the upper and lower boxes vacuum sucked and the pressure reduced from atmospheric pressure (101.3 kPa) to 1.0 kPa, the far-infrared heater 15 installed on the upper chamber box 11 is started at an output of 80% to form the decorative film 1. It was heated. Vacuum suction was continued during heating, and the pressure was finally reduced to 0.1 kPa. Five seconds after the decorative film 1 is heated and temporarily sags, and then the springback phenomenon of tensioning back is completed, the table 14 installed in the lower chamber box 12 is moved upward to form a resin molded body. The (base) 5 was pressed against the decorative film 1, and immediately after that, compressed air was sent so that the pressure in the upper chamber box 11 became 270 kPa to bring the resin molded body (base) 5 and the decorative film 1 into close contact with each other. In this way, a three-dimensional decorative thermoformed product 6 in which the decorative film 1 was attached to the upper surface and the side surface of the resin molded body (base) 5 was obtained.

-Evaluation of physical properties (1) Evaluation of thermoformability The draw-down state of the decorative film during three-dimensional decorative thermoforming, and the attached state of the decorative film of the decorative molded body with the decorative film attached to the substrate. It was visually observed and evaluated according to the criteria shown below.
◯: During three-dimensional decorative thermoforming, the decorative film did not draw down and the substrate and the decorative film were in contact with each other at the same time on the entire contact surface, so that contact unevenness did not occur and the film was evenly attached. ing.
X: During three-dimensional decorative thermoforming, the decorative film drew down significantly, causing uneven contact on the entire surface of the substrate.

(2) Adhesive strength between the resin molded body (base) and the decorative film "Craft Adhesive Tape No. 712N" manufactured by Nitoms Co., Ltd. was cut out to a width of 75 mm and a length of 120 mm, and from the end of the resin molded body (base). It was attached to a resin molded body (base) in a range of 75 mm × 120 mm and subjected to masking treatment (the exposed portion of the surface of the base has a width of 45 mm and a length of 120 mm). It was installed in the three-dimensional decorative thermoforming apparatus NGF-0406-SW so that the masking surface of the resin molded body (base) was in contact with the decorative film, and three-dimensional decorative thermoforming was performed.

The decorative film surface of the obtained decorative molded product was cut to the surface of the substrate with a width of 10 mm using a cutter in the direction perpendicular to the longitudinal direction of the adhesive tape to prepare a test piece. In the obtained test piece, the adhesive surface between the substrate and the decorative film has a width of 10 mm and a length of 45 mm. Attached to a tensile tester so that the base part of the test piece and the decorative film part are 180 °, 180 ° peel strength of the adhesive surface is measured at a tensile speed of 200 mm / min, and the maximum strength at the time of peeling or breaking is measured. (N / 10 mm) was measured 5 times, and the average strength was taken as the adhesive strength.

(3) Evaluation of the effect of making scratches inconspicuous Shape measurement of the scratch depth of the scratched part of the three-dimensional decorative thermoformed product of the molded body (base) damaged by a load of 15 N Laser microscope (Measured by KEYENCE "VX-X200"). The number of measurements was n = 5, and the average value was defined as the scratch depth (μm).
Further, as the whitening appearance, it was visually determined and evaluated based on the following criteria whether or not the whitening scratches on the molded body (base) damaged by the load of 15 N were not conspicuous by the decorative film.
◯: Traces of whitening scratches are inconspicuous, and the appearance is excellent.
X: Whitening scratches remain as a whole, and the appearance is poor.

(4) Gloss The gloss near the center of the decorative molded product to which the decorative film is attached was measured at an incident angle of 60 ° using a GLOSS meter Gloss Meter VG2000 manufactured by Nippon Denshoku Kogyo Co., Ltd. .. The measuring method was based on JIS K7105-1981.

(5) Evaluation of Recyclability The obtained decorative molded product was crushed to obtain a recycled molded product by injection molding in the same manner as in the production of the resin molded product (base), and the appearance was visually evaluated.

Table 1 shows the results of evaluation of the physical properties of the obtained decorative molded product and the like.
Since the polypropylene-based resin (A) and the polypropylene-based resin or the polypropylene-based resin composition (B) satisfy all the requirements of the present invention, the obtained decorative molded product has excellent appearance and adhesive strength, and scratches are conspicuous. It was gone. In addition, the recycled molded product had an excellent appearance (evaluation: ◯).

(Examples 2 to 5)
In the production of the decorative film of Example 1, the polypropylene-based resin used for the layer (II) was blended with (B-1-1) and (B-2-1) at the ratios shown in Table 1, and used as raw materials. Molding and evaluation were carried out in the same manner as in Example 1 except that it was used in. The results are shown in Table 1.
(Example 6)
In the production of the decorative film of Example 1, molding and evaluation were carried out in the same manner as in Example 1 except that the polypropylene-based resin used for the layer (II) was (B-1-2). The results are shown in Table 1.
(Examples 7 to 10)
In the production of the decorative film of Example 6, the polypropylene-based resin used for the layer (II) was blended with (B-1-2) and (B-2-1) at the ratios shown in Table 1, and the raw materials used were Molding and evaluation were carried out in the same manner as in Example 6 except that it was used in. The results of Examples 7 to 9 are shown in Table 1, and the results of Example 10 are shown in Table 2.

(Example 11)
In the production of the decorative film of Example 1, molding and evaluation were carried out in the same manner as in Example 1 except that the polypropylene-based resin used for the seal layer (I) was (A-2). The results are shown in Table 2.
(Example 12)
In the production of the decorative film of Example 1, molding and evaluation were carried out in the same manner as in Example 1 except that the polypropylene-based resin used for the seal layer (I) was (A-3). The results are shown in Table 2.
(Example 13)
In the production of the decorative film of Example 1, molding and evaluation were carried out in the same manner as in Example 1 except that the polypropylene-based resin used for the seal layer (I) was (A-4). The results are shown in Table 2.
(Example 14)
For the production of decorative films, a die with a lip opening of 0.8 mm and a seal layer extruder-1 having a diameter of 30 mmφ, an extruder-2 having a diameter of 40 mmφ, and a surface layer extruder-3 having a diameter of 30 mmφ are connected. A three-kind three-layer T-die with a width of 400 mm was used. A polypropylene-based resin (A-1) is used for the seal layer extruder-1, a polypropylene-based resin (B-1-1) is used for the extruder-2, and a polypropylene-based resin (B-2) is used for the surface layer extruder-3. -1) is charged, the resin temperature is 240 ° C., the discharge amount of the seal layer extruder-1 is 4 kg / h, the discharge amount of the surface layer extruder-1 is 8 kg / h, and the discharge amount of the surface layer extruder-1. The melt extrusion was performed under the condition that the discharge amount of the above was 4 kg / h.
The melt-extruded film was cooled and solidified while being pressed with an air knife against a first roll rotated at 3 m / min at 80 ° C. so that the surface decorative layer was in contact with the seal layer having a thickness of 50 μm and an intermediate layer having a thickness of 100 μm. To obtain a three-layer unstretched film in which a surface decorative layer having a thickness of 50 μm was laminated.
Other than that, the evaluation was performed in the same manner as in Example 1. The results obtained are shown in Table 2.
Compared with Example 1 in which the surface decoration layer was not laminated, the polypropylene-based resin (B-2-1) was laminated as the surface decoration layer (III), resulting in excellent gloss.

(Example 15)
In the three-dimensional decorative thermoforming, the heating time of the decorative film is extended, and 20 seconds after the springback phenomenon of tensioning is completed, molding and evaluation are performed in the same manner as in Example 1 except that the molding is performed. rice field. The results are shown in Table 2.
Even if the heating time of the decorative film was extended, the drawdown of the decorative film did not occur, and the decorative molded product had an excellent appearance.

(Comparative Example 1)
In the production of the decorative film of Example 1, molding and evaluation were carried out in the same manner as in Example 1 except that the polypropylene-based resin used for the seal layer (I) was (A-5). The results are shown in Table 2.
Since the polypropylene-based resin (A-5) has a high Mw / Mn of 4.0, the adhesive strength is small, and the appearance of scratches cannot be sufficiently suppressed, resulting in poor appearance.

(Comparative Example 2)
In the production of the decorative film of Example 1, the polypropylene-based resin used for the seal layer (I) was designated as (A-5), and the polypropylene-based resin used for the layer (II) was designated as (B-2-2). .. Further, in the three-dimensional decorative thermoforming, the heating time of the decorative film is extended, and 20 seconds after the springback phenomenon of tensioning is completed, the molding is performed in the same manner as in Example 1, except that the molding is performed. Was done. The results are shown in Table 2.
By extending the heating time of the decorative film, the adhesive strength was excellent, but the drawdown of the decorative film caused uneven contact, and the appearance was significantly inferior. Scratches and surface gloss were not evaluated due to their significantly inferior appearance.

(Example 16)
In the three-dimensional decorative thermoforming of Example 1, the evaluation was carried out in the same manner as in Example 1 except that the substrate was changed to an injection molded product using a resin (X-2). The results obtained are shown in Table 3.
Since the polypropylene-based resin (A) and the polypropylene-based resin composition (B) satisfy all the requirements of the present invention, the obtained decorative molded product has excellent appearance and adhesive strength, and scratches are not noticeable. Met. In addition, the recycled molded product had an excellent appearance.

(Example 17)
In the three-dimensional decorative thermoforming of Example 1, the evaluation was carried out in the same manner as in Example 1 except that the substrate was changed to an injection molded product using a resin (X-3). The results obtained are shown in Table 3.

(Example 18)
In the production of the decorative film of Example 14, the polypropylene-based resin (B-2-1) charged into the surface layer extruder-3 was changed to the polypropylene-based resin (C-1), except that the polypropylene-based resin (B-2-1) was changed to the polypropylene-based resin (C-1). The evaluation was performed in the same manner. The results obtained are shown in Table 3.
The polypropylene resin (C-1) to which the nucleating agent was added was laminated on the outermost surface side as the surface decorative layer (III), resulting in excellent gloss.

(Example 19)
In the production of the decorative film of Example 14, the polypropylene-based resin (B-2-1) charged into the surface layer extruder-3 was changed to the polypropylene-based resin (A-1), except that the polypropylene-based resin (B-2-1) was changed to the polypropylene-based resin (A-1). The evaluation was performed in the same manner. The results obtained are shown in Table 3.
The polypropylene-based resin (A-1) was laminated on the outermost surface side as the surface decorative layer (III), resulting in excellent gloss.

(Example 20)
In the production of the decorative film of Example 14, the polypropylene-based resin (B-2-1) charged into the surface layer extruder-3 was changed to the polypropylene-based resin (C-2), except that the polypropylene-based resin (B-2-1) was changed to the polypropylene-based resin (C-2). The evaluation was performed in the same manner. The results obtained are shown in Table 3.
The polypropylene-based resin (C-2) to which the nucleating agent was added was laminated on the outermost surface side as the surface decorative layer (III), resulting in excellent gloss.

(Example 21)
In the production of the decorative film of Example 14, the polypropylene-based resin (B-2-1) charged into the surface layer extruder-3 was changed to the polypropylene-based resin (C-3), except that the polypropylene-based resin (B-2-1) was changed to the polypropylene-based resin (C-3). The evaluation was performed in the same manner. The results obtained are shown in Table 3.
Coupled with the fact that the decorative film colored in white was attached, the scratches were sufficiently concealed so that the damaged part could not be identified. Therefore, the wound depth was not measured. Further, since the surface decorative layer (III) having excellent gloss was colored white, the appearance was excellent.

(Example 22)
In the production of the decorative film of Example 14, the evaluation was carried out in the same manner as in Example 14 except that the polypropylene-based resin (B-1-1) was changed to the polypropylene-based resin (B-1--3). The results obtained are shown in Table 3.
Since the polypropylene-based resin (A) and the polypropylene-based resin composition (B) all satisfy the requirements of the present invention, the obtained decorative molded product was excellent in appearance and adhesive strength. In addition, the black-colored decorative film was attached, and the scratches were sufficiently concealed so that the damaged part could not be identified. Therefore, the wound depth was not measured. Further, since the layer (II) was colored black, the appearance was excellent. Further, since the polypropylene-based resin (B-2-1) is laminated on the outermost surface side as the surface decorative layer (III), the result is excellent in gloss.

(Example 23)
In the production of the decorative film of Example 22, the polypropylene-based resin (B-2-1) charged into the surface layer extruder-3 was changed to the polypropylene-based resin (C-4), except that the polypropylene-based resin (B-2-1) was changed to the polypropylene-based resin (C-4). The evaluation was performed in the same manner. The results obtained are shown in Table 3.
Coupled with the fact that the colored decorative film was attached, the scratches were sufficiently concealed so that the damaged part could not be identified. Therefore, the wound depth was not measured. Further, since the polypropylene-based resin (C-4) was laminated on the outermost surface side as the surface decorative layer (III), the result was excellent in gloss. Further, since the layer (II) is colored black and the surface decorative layer (III) is colored silver, the film is metallic and has an excellent appearance.

According to the present invention, sufficient adhesive strength and product appearance can be achieved at the same time, there is little wrinkle return, product defects can be reduced by making scratches on the substrate inconspicuous, and three-dimensional addition that facilitates recycling. A decorative film used for decorative thermoforming and a method for producing a decorative molded product using the same are provided.

1 Decorative film 2 layers (II)
3 Seal layer (I)
5 Resin molded body (decoration target, substrate)
6 Decorative molding 11 Upper chamber box 12 Lower chamber box 13 Jig 14 Table 15 Heater

Claims (9)

A decorative film for being adhered onto a resin molded body by thermal molding, wherein the decorative film is a seal layer (I) made of a polypropylene-based resin (A) and a polypropylene-based resin or a polypropylene-based resin composition ( Includes layer (II) consisting of B)
The polypropylene-based resin (A) satisfies the following requirements (a1) to (a4), and the polypropylene-based resin or polypropylene-based resin composition (B) satisfies the following requirements (b1) to (b3). Decorative film to be.
(A1) The melt flow rate (230 ° C., 2.16 kg load) (MFR (A)), which is a metallocene-catalyzed propylene-based polymer, exceeds 0.5 g / 10 minutes (a3). Tm (A)) is less than 150 ° C. (a4) The molecular weight distribution (Mw / Mn (A)) obtained by GPC measurement is 1.5 to 3.5 (b1) Melt flow rate (230 ° C.). , 2.16 kg load) (MFR (B)) is 40 g / 10 minutes or less (b2) Strain hardening degree λ is 1.1 or more (b3) Melting peak temperature (Tm (B)) and Tm (A) is Tm (B)> Tm (A) ... Equation (b-3) that satisfies the relational expression (b-3).
However, the polypropylene resin (A) is not MFR (A): 2.0 g / 10 minutes, Tm (A): 125-126 ° C., and Mw / Mn (A): 2.8. The decorative film according to claim 1, wherein the polypropylene-based resin (A) is a propylene / α-olefin copolymer. The decorative film according to claim 1 or 2, wherein Tm (A) is 140 ° C. or lower. The decorative film according to any one of claims 1 to 3, wherein the polypropylene-based resin or polypropylene-based resin composition (B) satisfies the following requirements (b1') to (b2').
(B1') MFR (B) is 20 g / 10 minutes or less (b2') Strain hardening degree λ is 1.8 or more. The decorative film according to claim 1 or 4, wherein the polypropylene-based resin or polypropylene-based resin composition (B) satisfies the following requirements (b1 ") to (b2").
(B1 ") MFR (B) is 12 g / 10 minutes or less (b2") Strain hardening degree λ is 2.3 or more. The decorative film according to any one of claims 1 to 5, wherein the polypropylene-based resin or polypropylene-based resin composition (B) contains a polypropylene-based resin (B-1) having a long-chain branched structure. .. The decorative film according to claim 6, wherein the polypropylene-based resin (B-1) is a polypropylene-based resin produced by a method other than a cross-linking method and having a small amount of gel. The step of preparing the decorative film according to any one of claims 1 to 7, the step of preparing a resin molded body, the step of setting the resin molded body and the decorative film in a decompressable chamber box, the step. Includes a step of depressurizing the inside of the chamber box, a step of heating and softening the decorative film, a step of pressing the decorative film against the resin molded body, and a step of returning or pressurizing the inside of the depressurized chamber box to atmospheric pressure. A method for manufacturing a decorative molded product. The method for producing a decorative molded product according to claim 8, wherein the resin molded product uses a propylene-based resin composition as a base material.

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