WO2021124943A1 - Layered body, molded article, and method for producing molded article - Google Patents

Abstract

A layered body including a first resin layer, a second resin layer, and a third resin layer, in this order, wherein the first resin layer and the second resin layer each contain polypropylene, each polypropylene has a long-chain branching structure and a crystallization speed of 2.5 min-1 or slower at 130°C, the first resin layer and the second resin layer have different compositions, and the third resin layer contains an adhesive having a melting point of 125°C or lower.

Description

Laminated body, molded body and manufacturing method of molded body

The present invention relates to a laminate, a molded product, and a method for producing a molded product, which can suppress drawdown during molding and can produce a molded product having an excellent appearance.

Painting is used as a method for improving the design of appearance in various fields such as automobiles, home appliances, building materials, daily necessities, and information and communication equipment. However, painting has a large environmental load such as discharging a large amount of VOC (volatile organic compounds).
As an alternative technique to painting, a technique has been proposed in which a decorative sheet is integrated with a molded body to form a decorative molded product (Patent Documents 1 and 2). In recent years, there has been increasing interest in environmental issues, and polypropylene-based resins are attracting more attention as materials for decorative sheets than amorphous resins such as polystyrene and ABS (acrylonitrile, butadiene, and styrene copolymers).

Japanese Unexamined Patent Publication No. 2018-24246 Japanese Unexamined Patent Publication No. 2013-14027

Polypropylene resin, which has been conventionally used for decorative sheets for vacuum pressure molding, has low melt tension, so that it cannot be said that the drawdown resistance is sufficient in the process of thermoforming the sheet, and it can be used as a molded body during large-scale molding. Wrinkles and molding unevenness caused by drawdown occurred. In particular, in coating molding, which is a type of decorative molding method, the core material used for coating molding is often large, such as automobile parts, but there is no polypropylene decorative sheet with excellent draw-down resistance. Wrinkles and uneven molding were the main causes of lowering the non-defective rate.

In addition, most of the sheets using polypropylene-based resin smooth the surface of the sheet and increase the surface gloss by pressing the molten resin between the mirror rolls or pressing the resin against the mirror rolls with air pressure. However, when the sheet is heat-molded, there is a problem that the gloss of the sheet surface is lost due to the growth of spherulite or the like, or the transparency is lowered and the appearance is impaired. Further, in order to impart transparency to a sheet using a polypropylene resin, a nucleating agent (also referred to as "crystal nucleating agent") has been conventionally used, but a sheet using a nucleating agent is crystallized. Since the speed is high, the sheet that comes into contact with the mold during molding rapidly crystallizes and the stretchability deteriorates. Therefore, the conventional transparent sheet containing a polypropylene resin has a problem that it is difficult to form a complicated shape and fine irregularities of a mold.

In addition, the coating molding apparatus usually has a smaller amount of heat during molding as compared with other decorative molding methods such as insert molding and in-mold molding. Therefore, for the decorative sheet used for coating molding, an adhesive that can strongly adhere to the core material even at a low temperature is used. However, since the adhesive has tackiness even at room temperature, it has a problem that it has poor handleability and foreign matter easily adheres to it. Further, in addition to the decorative sheet manufacturing process, adhesive laminating and coating processing and adhesive purchasing costs are required separately, which leads to an increase in the cost of the decorative molding process using a coating molding machine.

The technique of Patent Document 1 relates to a thermoforming sheet made of high melt tension polypropylene having a long chain branched structure. However, since polypropylene is a crystalline resin, there is a concern that the sheet in contact with the mold will crystallize rapidly and the stretchability will deteriorate. Further, there is a concern that the sheet crystallizes after heat molding to cause fine irregularities on the surface of the molded product to lose its luster, or to lose its transparency and impair the appearance of the sheet.

The technique of Patent Document 2 is that it is a coating substitute film and includes an adhesive layer having excellent adhesiveness to polypropylene. However, since the melting point of the adhesive layer is 130 ° C. or higher, the adhesive layer does not rise to the above temperature in coating molding or the like, and the adhesive strength may not be exhibited, or the laminated body may be damaged by overheating. is there. Further, since polypropylene which is a base material of the laminated body can be presumed to be polypropylene which does not have a branched structure, the drawdown is large, and there is a concern that the molded product may have an appearance defect due to wrinkles or uneven molding.

An object of the present invention is to provide a laminate capable of suppressing drawdown during molding, having excellent adhesive strength with an adherend, and being able to produce a molded body having an excellent appearance.

According to the present invention, the following laminates and the like are provided.
1. 1. A laminate containing a first resin layer, a second resin layer, and a third resin layer in this order.
The first resin layer and the second resin layer contain polypropylene, each of which has a long-chain branched structure and a crystallization rate at 130 ° C. of 2.5 min ^-1 or less. ,
The composition of the first resin layer and the second resin layer are different.
The third resin layer contains an adhesive having a melting point of 125 ° C. or lower.
Laminated body.
2. The adhesive of the third resin layer is one or more selected from the group consisting of an olefin adhesive, a styrene adhesive, an isocyanate adhesive, a urethane adhesive, and an acrylic adhesive. The laminate described in.
3. 3. The laminate according to 1 or 2, wherein the second resin layer contains a pigment.
4. Polypropylene of one or more resin layers selected from the group consisting of the first resin layer and the second resin layer is 1 J / g or more on the low temperature side of the maximum endothermic peak in the curve obtained by differential scanning calorimetry. The laminate according to any one of 1 to 3, which has an endothermic peak of.
5. The laminate according to any one of 1 to 4, wherein the polypropylene of one or more resin layers selected from the group consisting of the first resin layer and the second resin layer contains smetica crystals.
6. 5. The laminate according to 5, wherein spherulites having a diameter of 1 μm to 10 μm are present in one or more of the resin layers containing the smetika crystals, and the volume fraction of the spherulites in the resin layer is 20% or less.
7. Any of 1 to 6 in which the polypropylene isotactic pentad fraction of one or more resin layers selected from the group consisting of the first resin layer and the second resin layer is 85 to 99 mol%. The laminate described in.
8. The description in any one of 1 to 7, wherein the polypropylene branching index of one or more resin layers selected from the group consisting of the first resin layer and the second resin layer is 0.50 or more and less than 1.00. Laminated body.
9. The laminate according to any one of 1 to 8, wherein the polypropylene of one or more resin layers selected from the group consisting of the first resin layer and the second resin layer has a melt tension of 4.0 g or more.
10. The laminate according to any one of 1 to 9, further comprising an easy-adhesion layer.
11. 10. The laminate according to 10, wherein the easy-adhesion layer contains one or more resins selected from the group consisting of urethane, acrylic, polyolefin and polyester.
12. 10. The laminate according to 10 or 11, further comprising a print layer laminated on the surface of the easy-adhesion layer opposite to the first resin layer.
A molded product produced by using the laminate according to any one of 13.1 to 12.
A method for producing a molded product, which comprises molding the laminate according to any one of 14.1 to 12 to obtain a molded product.
15. The laminated body is shaped so as to match the mold, the shaped laminated body is mounted on the mold, a molding resin is supplied, and the molded laminated body is integrated with the shaped laminated body to perform the molding. The method for producing a molded product according to.
16. The core material is arranged in the chamber box, the laminated body is arranged above the core material, the laminated body is heated and softened, and the inside of the chamber box is depressurized to heat and soften the laminated body. The method for producing a molded body according to 14, wherein the material is pressed and covered.

According to the present invention, it is possible to provide a laminated body capable of suppressing drawdown during molding, having excellent adhesive strength with an adherend, and being able to manufacture a molded body having an excellent appearance.

It is a schematic block diagram of an example of the manufacturing apparatus for manufacturing the laminated body of this invention. It is a figure for demonstrating the measurement method of the drawdown amount.

Hereinafter, the laminated body, the molded body, and the manufacturing method of the molded body according to the present invention will be described. In the present specification, "x to y" represents a numerical range of "x or more and y or less".

1. 1. Laminated body The laminated body according to one aspect of the present invention is
A laminate containing a first resin layer, a second resin layer, and a third resin layer in this order.
The first resin layer and the second resin layer contain polypropylene, each of which has a long-chain branched structure and a crystallization rate at 130 ° C. of 2.5 min ^-1 or less. (The polypropylene is also referred to as "polypropylene X" below),
The composition of the first resin layer and the second resin layer are different.
The third resin layer contains an adhesive having a melting point of 125 ° C. or lower.

Since the laminate contains polypropylene X in the first resin layer and the second resin layer, it has a high melt tension, so that it can be drawn during thermoforming (for example, vacuum forming, compressed air forming, or vacuum forming). Down can be suppressed. As a result, it is possible to manufacture a molded product in which wrinkles, unevenness, slack marks and the like caused by the drawdown are prevented or reduced. Further, since the melt tension is large, uneven thickness is unlikely to occur in the molded body even if the draw ratio is increased. Further, the laminate has high moldability because rapid crystallization is unlikely to occur due to the low crystallization rate of polypropylene contained in the first resin layer and the second resin layer. That is, for example, since the laminated body does not cure rapidly at the time of contact with the mold, it is possible to realize a desired shape with a high degree of freedom. Further, according to the above-mentioned laminated body, deterioration of the appearance (gloss and transparency) that tends to occur during thermoforming is suppressed, so that a beautiful molded body can be manufactured while maintaining the appearance. The above effects are suitably exhibited even during large-scale molding (for example, one side is 1 meter or more).

Further, in the above-mentioned laminated body, by containing an adhesive having a melting point of 125 ° C. or less in the third resin layer, the third resin layer can be used as an adhesive layer for adhering the laminated body to the adherend. At this time, since the third resin layer can exhibit adhesiveness at a low temperature of 125 ° C. or lower, excellent adhesion is achieved even when a molding method such as coating molding in which the temperature rise is relatively small (the amount of heat generated is small) is used. Strength is obtained. Further, since the adhesiveness can be exhibited at a low temperature of 125 ° C. or lower, the adhesive can be adhered by gentle heating, and the laminated body can be prevented from being damaged by overheating. It is also possible to obtain the effect of significantly reducing costs by omitting the adhesives and coatings that have been used in the past. Further, by using an adhesive instead of an adhesive that exhibits tackiness at room temperature, the handling property can be improved and the risk of foreign matter adhesion can be reduced.

(First resin layer)
The first resin layer contains polypropylene X. In one embodiment, the first resin layer can be used as a translucent clear layer.

A branching index g'is given as an index that polypropylene X has a long-chain branched structure. The definition of the branch 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, g'<1 If this is the case, it is determined that the long-chain branched structure exists in the polymer X, and it can be said that the smaller the value of g', the more long-chain branched structures are present. Here, the intrinsic viscosity is a value measured at 140 ° C. The divergence index g'is measured by the method described in the examples.

The branching index of polypropylene X contained in the first resin layer is preferably 0.50 or more and less than 1.00.

The melt tension of polypropylene X contained in the first resin layer is preferably 4.0 g or more, and more preferably 5.0 g or more. The upper limit is not particularly limited, for example, 20 g or less.
The melt tension is measured by the method described in the examples.

The melt flow rate (MFR) of polypropylene X is preferably 1.0 to 10.0 g / 10 min (2.16 kg). Within this range, extrusion moldability is excellent, and flow such as drawdown is unlikely to occur during vacuum compressed air molding, which is preferable.
MFR is measured by the method described in the examples.

Propylene X is a propylene homopolymer obtained by homopolymerizing propylene by single-stage polymerization or multi-stage polymerization of two or more stages, and copolymerizing propylene and α-olefin by single-stage polymerization or multi-stage polymerization of two or more stages. The obtained propylene / α-olefin random copolymer, a polymerization step of homopolymerizing propylene by single-stage polymerization or multi-stage polymerization of two or more stages to obtain a propylene homopolymer, and monostage polymerization or two-stage polymerization of propylene and α-olefin. It may be any propylene / α-olefin block copolymer obtained by polymerization including a copolymerization step of copolymerizing by multi-stage polymerization of steps or more to obtain a propylene / α-olefin random copolymer, but propylene. A homopolymer and a propylene / α-olefin random copolymer are preferable.

The α-olefin is preferably ethylene or an α-olefin having 4 to 18 carbon atoms. Specifically, ethylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-heptene, 4-methyl-pentene-1, 4-methyl-hexene-1, 4,4-dimethylpentene- 1st grade can be mentioned. Further, the α-olefin may be one kind or a combination of two or more kinds.

Polypropylene X can be obtained by, for example, a so-called macromer copolymerization method in which a propylene macromer having a terminal double bond is polymerized from a propylene monomer and the propylene macromer and the propylene monomer are copolymerized, but the polypropylene X is not limited thereto.

Polypropylene X contained in the first resin layer has a crystallization rate of 2.5 min ^-1 or less at ^{130 ° C., 2.4 min -1} or less, 2.3 min ^-1 or less, 2.2 min ^-1 or less, It can be 2.1 min ^-1 or less or 2.0 min ^{-1 or less.} The lower limit is not particularly limited and is, for example, 0.05 min ^-1 or more.

Further, it is preferable that the first resin layer contains little or no nucleating agent. The content of the nucleating agent in the first resin layer is preferably 1.0% by mass or less, and more preferably 0.5% by mass or less.
Examples of the nucleating agent include sorbitol-based nucleating agents, and commercially available products include Gelol MD (Nihon Rikagaku Co., Ltd.) and Rikemaster FC-1 (RIKEN Vitamin Co., Ltd.).

As a method of making polypropylene, which is a crystalline resin, transparent, there is a method of forcibly producing fine crystals by adding a nucleating agent. In this method, the crystallization rate is increased ^{to a rate exceeding 2.5 min -1} by a nucleating agent, a large number of crystals are generated to achieve a high filling state, and the space in which each crystal physically grows is limited to obtain crystals. Miniaturize. However, since the nucleating agent has a core substance, transparency can be obtained, but the design is usually low because it is slightly whitish. In addition, since the crystallization rate is high, when the heat-softened laminate is brought into contact with the mold, the portion that first comes into contact with the mold hardens rapidly and the elongation (ductility) deteriorates, and the laminate is forcibly stretched. There is a risk that the part will be whitened and the design will be reduced. Due to the deterioration of ductility, it may be difficult to form a complicated shape or fine irregularities of a mold.

On the other hand, in the first resin layer, even if the content of the nucleating agent is low or not contained ^{, whitening is prevented by setting the crystallization rate to 2.5 min -1} or less, and the design (appearance). ) Can be obtained. In addition, it is easy to attach a complicated shape or a fine uneven shape of a mold to the molded body.

The first resin layer preferably contains Smetica crystals.
Polypropylene is a crystalline resin and can take a crystalline form such as α crystal, β crystal, γ crystal, and Smetica crystal. Of these crystalline forms, smetica crystals can be produced as intermediates between amorphous and crystalline by cooling polypropylene from a molten state at a rate of 80 ° C. or higher per second. Smetica crystals are not stable structures having a regular structure like crystals, but metastable structures in which fine structures are gathered together. Therefore, the interaction between the molecular chains is weak, and it has a property of being easily softened when heated as compared with α crystals and the like having a stable structure.
The crystal structure of the first resin layer is measured by the method described in Examples.

When the first resin layer has spherulite crystals, spherulites having a diameter of 1 μm to 10 μm are present in the first resin layer, and the volume fraction of the spherulites in the first sheet is 20%. It is preferable that it is as follows. The volume fraction of the spherulite may be 15% or less or 10% or less.
The volume fraction of spherulite is measured by the method described in Examples.
In one embodiment, polypropylene spherulites may be composed of α-crystals.
The description of spherulite and spherulite is also appropriately incorporated into the second resin layer.

By satisfying the above crystal conditions, the appearance and moldability of the molded product can be further improved. Further, when the laminate is heated with an infrared heater or the like to form an attachment, the laminate is transferred to α crystals while maintaining the fine structure derived from Smetica crystals. This transition prevents a decrease in gloss and a decrease in transparency due to molding, and thermoforming can be performed while maintaining a beautiful appearance. In addition, this transition further improves the surface hardness and transparency as compared with the case where the above-mentioned nucleating agent is used.

Further, by calculating the scattering intensity distribution and the long period by the small-angle X-ray scattering analysis method, it is determined whether the laminated body (decorative sheet) is obtained by cooling at 80 ° C./sec or more, or not. be able to. That is, it is possible to determine whether or not the laminated body (decorative sheet) has a fine structure derived from Smetica crystals by the above analysis.
The measurement is performed under the following conditions.
An ultraX 18HF (manufactured by Rigaku Co., Ltd.) is used as an X-ray generator, and an imaging plate is used to detect scattering.
-Light source wavelength: 0.154 nm
・ Voltage / current: 50kV / 250mA
・ Irradiation time: 60 minutes ・ Camera length: 1.085m
-Stack the laminates so that the sample thickness is 1.5 to 2.0 mm. In addition, the laminated bodies are stacked so that the film forming (MD) directions are aligned.

The first resin layer has an exothermic peak of 1 J / g or more, preferably 1.5 J / g or more on the low temperature side of the maximum endothermic peak in the curve (DSC curve) obtained by differential scanning calorimetry (DSC) measurement (“low temperature side”). It is preferable to have an exothermic peak (also referred to as).
The calorific value of the low temperature side exothermic peak is measured by the method described in Examples.

In the first resin layer, the isotactic pentad fraction of polypropylene X is preferably 85-99 mol%. When the isotactic pentad fraction is 85 mol% or more, the surface hardness is excellent, and the appearance is easily maintained by preventing surface damage.
The isotactic pentad fraction is an isotactic fraction in a pentad unit (five consecutive isotactic bonds of five propylene monomers) in the molecular chain of the resin composition. A method for measuring this fraction is described in, for example, Macromolecules, Volume 8 (1975), p. 687, and can be measured by ^{13 C-NMR.}
The isotactic pentad fraction of polypropylene X is preferably 90 mol% or more.
The isotactic pentad fraction is measured by the method described in Examples.

The first resin layer may contain other components in addition to polypropylene X, and examples of the other components include one or more types of polypropylene having no long-chain branched structure, other resin components, and additives. And so on.
In the first resin layer, the content of components other than polypropylene X is, for example, 50 parts by mass or less, 40 parts by mass or less, 30 parts by mass or less, and 20 parts by mass or less with respect to 100 parts by weight of polypropylene X. Or it can be 10 parts by mass or less.

The polypropylene having no long-chain branched structure (polypropylene having a branching index of 1) is not particularly limited, and is a polymer containing at least a structural unit derived from propylene. Specific examples thereof include copolymers of homopolypropylene and propylene with other olefins (ethylene, butylene, cycloolefin, etc.). It may be a mixture in which a polyolefin such as polyethylene (for example, linear low-density polyethylene) or a copolymer is mixed with polypropylene. These may be used individually by 1 type or in combination of 2 or more type.
The content of polypropylene having no long-chain branched structure in the first resin layer is, for example, 1 part by mass or more and, for example, 40 parts by mass or less with respect to 100 parts by mass of polypropylene.

Examples of other resin components include elastomers and the like. Examples of the elastomer include thermoplastic elastomers such as olefin-based elastomers, styrene-based elastomers, polyvinyl chloride-based elastomers, urethane-based elastomers, polyester-based elastomers, and polyamide-based elastomers. In one embodiment, the thermoplastic elastomer is an olefin-based elastomer. As the olefin-based elastomer, a commercially available product such as "Engage 8200" manufactured by Dow Chemical Co., Ltd. may be used.
The content of the other resin component in the first resin layer is, for example, 1 part by mass or more and, for example, 10 parts by mass or less with respect to 100 parts by mass of polypropylene X.

Examples of the additive include an antistatic agent and the like.
The content of the other additive in the first resin layer is, for example, 0.1 part by mass or more and, for example, 10 parts by mass or less with respect to 100 parts by mass of polypropylene X.

The first resin layer may be made of polypropylene X only, or may be substantially made of polypropylene X only. In the latter case, the first resin layer may contain unavoidable impurities.
The first resin layer is 50% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more, 90% by mass or more, 95% by mass or more, 99% by mass or more, 99.5% by mass or more, 99. .9% by mass or more, or 100% by mass,
It may be polypropylene X, polypropylene X, and one or more components selected from each of the above optional components.

The thickness of the first resin layer is usually 30 μm to 180 μm.

(Second resin layer)
The second resin layer contains polypropylene X having a long-chain branched structure and having a crystallization rate at 130 ° C. of 2.5 min- ^{1 or less.} Regarding polypropylene X contained in the second resin layer, the description of polypropylene X contained in the first resin layer, including its crystal structure and the like, is incorporated. The polypropylene X contained in the second resin layer may be the same as or different from the polypropylene X contained in the first resin layer, including its crystal structure and the like.

The composition of the second resin layer is different from that of the first resin layer. Here, "different composition" may mean that the components contained in the resin layer are different (for example, one or more components are contained in one layer but not in the other component). , The amount of one or more components contained in the resin layer may be different.

Like the first resin layer, the second resin layer preferably has a low temperature side heat generation peak of 1 J / g or more, preferably 1.5 J / g or more.

The second resin layer can be a colored layer. In this case, the second resin layer can contain a colorant. In one embodiment, the second resin layer contains the same components as the first resin layer, except that it contains a colorant. In one embodiment, the first resin layer usually does not contain a colorant, but when the first resin layer contains a colorant, the second resin layer has a higher content than the first resin layer. May contain colorants. In one embodiment, the content of polypropylene X in the second resin layer is lower than the content of polypropylene X in the first resin layer.
Colorants are not particularly limited, and examples thereof include general colorants such as organic pigments, inorganic pigments, and dyes, but are not limited thereto.
The content of the colorant in the second resin layer is, for example, 0.1 part by mass or more and, for example, 10 parts by mass or less with respect to 100 parts by mass of polypropylene X.

Further, the second resin layer may contain a metal foil powder and a pearl-like pigment. Examples of the metal leaf powder include crushed atypical flat pieces obtained by crushing a sheet in which both sides of the metal thin film layer are coated with the transparent thin film layer. Examples of the pearl pigment include atypical flat pieces containing mica (mica) as a main component.

The content of the metal leaf powder or the pearl pigment in the second resin layer is, for example, 0.1 part by mass or more and, for example, 10 parts by mass or less with respect to 100 parts by mass of polypropylene X.

Further, the second resin layer can contain other components described for the first resin layer, for example, within the range of the content described for the first resin layer. The first resin layer may contain the colorant, the metal leaf powder, and the pearl pigment described for the second resin layer, for example, within the range of the content described for the second resin layer.

The second resin layer may be made of polypropylene X only, or may be substantially made of polypropylene X only. In the latter case, the second resin layer may contain unavoidable impurities.
The second resin layer is 50% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more, 90% by mass or more, 95% by mass or more, 99% by mass or more, 99.5% by mass or more, 99. .9% by mass or more, or 100% by mass,
It may be polypropylene X, polypropylene X, and one or more components selected from each of the above optional components.

The thickness of the second resin layer is usually 100 μm to 250 μm.

(Third resin layer)
The third resin layer contains an adhesive having a melting point of 125 ° C. or lower.
Adhesives having a melting point of 125 ° C. or lower are not particularly limited, and examples thereof include olefin-based adhesives, styrene-based adhesives, isocyanate-based adhesives, urethane-based adhesives, and acrylic-based adhesives. Examples of the olefin adhesive include a low melting point polypropylene resin having a melting point of 125 ° C. or lower.

The third resin layer can be an adhesive layer. In this case, the third resin layer contains the above-mentioned adhesive having a melting point of 125 ° C. or lower (also referred to as “adhesive component”), so that the third resin layer has an arbitrary coating at a temperature of 125 ° C. or lower (and a temperature of the melting point or higher). It can exhibit adhesiveness to the body.

In one embodiment, the third resin layer is used to bond the laminate to the adherend. In this case, the material of the adherend is not particularly limited, and examples thereof include resin and the like. Examples of the resin include polypropylene and ABS (acrylonitrile-butadiene-styrene copolymer). In particular, when the adherend is made of a polypropylene-based resin, it is preferable that the third resin layer contains an olefin-based adhesive having a melting point of 125 ° C. or lower because the adhesion strength is increased.

When the laminate is adhered to the adherend by the third resin layer, peeling between the third resin layer and the adherend and peeling between the third resin layer and the second resin layer occur practically. It is preferable not to do so. Specifically, it is preferable that the peel strength of the laminate and the adherend in the 180 ° peel test or the breaking strength at which the laminate breaks in the 180 ° peel test is 18 N / 15 mm or more. The 180 ° peeling test of the laminate and the adherend is performed by the method described in the examples.

The melting point of the adhesive contained in the third resin layer is 125 ° C. or lower, for example, 120 ° C. or lower, 118 ° C. or lower, 115 ° C. or lower, 112 ° C. or lower, 110 ° C. or lower, 105 ° C. or lower, 103 ° C. or lower, or It can be below 100 ° C. The lower limit is not particularly limited and may be, for example, 60 ° C. or higher.

In one embodiment, the adhesive contained in the third resin layer is a thermoplastic resin.
In one embodiment, the adhesive contained in the third resin layer is a hot melt adhesive.
In one embodiment, the adhesive contained in the third resin layer is not a pressure-sensitive adhesive having tackiness (adhesiveness) at room temperature (25 ° C.). The adhesive is one that adheres to the adherend by applying pressure by utilizing the tackiness of the surface, and is distinguished from the adhesive that exhibits peeling resistance by solidification.
In one embodiment, the melt flow rate (MFR) of the adhesive contained in the third resin layer is 1.0 to 10.0 g / 10 min (2.16 kg).
MFR is measured by the method described in the examples.

The melting enthalpy (ΔH) of the adhesive having a melting point of 125 ° C. or lower contained in the third resin layer is preferably 80 j / g or less. When ΔH is 80 j / g or less, the amount of heat required to melt the adhesive raw material is small, so that excellent adhesion strength is exhibited even in a molding method such as coating molding in which the temperature rise is relatively small (the amount of heat generated is small). It is preferable. The melt enthalpy (ΔH) of the adhesive can be, for example, 70 j / g or less, 60 j / g or less, 50 j / g or less, 40 j / g or less, 30 j / g or less. The lower limit is not particularly limited and may be, for example, 5 j / g or more.
The melt enthalpy (ΔH) of the adhesive is measured by the method described in Examples.

The adhesive layer may contain components other than the adhesive having a melting point of 125 ° C. or lower. Examples of other components include a tackifier such as petroleum resin and a plasticizer.

The third resin layer may consist only of an adhesive having a melting point of 125 ° C. or lower, or may consist of only an adhesive having a melting point of 125 ° C. or lower. In the latter case, the third resin layer may contain unavoidable impurities.
The third resin layer is 50% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more, 90% by mass or more, 95% by mass or more, 99% by mass or more, 99.5% by mass or more, 99. .9% by mass or more, or 100% by mass,
An adhesive having a melting point of 125 ° C. or lower, an adhesive having a melting point of 125 ° C. or lower, and one or more components selected from each of the above optional components may be used.

The thickness of the third resin layer is usually 10 μm to 100 μm.

(Easy adhesive layer)
In one embodiment, the laminate further includes an easy-adhesion layer in addition to the first to third resin layers described above. The easy-adhesion layer is provided for the purpose of laminating another layer (for example, a hard coat layer, a printing layer, a metal layer, etc.) on the first resin layer via the easy-adhesion layer. be able to. The easy-adhesion layer can be provided, for example, on the surface of the first resin layer opposite to the second resin layer.

The easy-adhesion layer preferably contains one or more resins selected from the group consisting of urethane, acrylic, polyolefin and polyester.
The resin of the easy-adhesion layer is preferably a urethane resin in view of adhesion to a laminate (main body) including the first to third layers and a printing layer described later and moldability. As a result, a laminate having excellent ink adhesion can be obtained.
The urethane resin is preferably a reaction product of diisocyanate, high molecular weight polyol and chain extender. Examples of the high molecular weight polyol include a polyether polyol and a polycarbonate polyol. As a result, even when the laminated body is formed into a complicated non-planar shape, the easy-adhesive layer follows the laminated body and good molding is realized. Further, even when the print layer described later is formed, cracks and peeling of the print layer can be prevented.

The thickness of the easy-adhesion layer is preferably 0.01 μm or more and 3 μm or less, and more preferably 0.03 μm or more and 0.5 μm or less. If the thickness of the easy-adhesion layer is thinner than 0.01 μm, sufficient ink adhesion may not be obtained. On the other hand, if it is thicker than 3 μm, stickiness may occur and cause blocking.

The tensile elongation at break of the easy-adhesion layer is preferably 150% or more and 900% or less, more preferably 200% or more and 850% or less, and particularly preferably 300% 750% or less.
If the tensile elongation at break of the easy-adhesive layer is less than 150%, the easy-adhesive layer cannot follow the elongation of the laminate during thermoforming, and cracks occur, causing cracks in the printed layer and metal layer. There is a risk of peeling. On the other hand, if the tensile elongation at break exceeds 900%, the water resistance may deteriorate.
The tensile elongation at break can be measured with a sample having a thickness of 150 μm, for example, by a method according to JIS K7311.

The softening temperature of the easy-adhesion layer is preferably 50 ° C. or higher and 180 ° C. or lower, more preferably 90 ° C. or higher and 170 ° C. or lower, and particularly preferably 100 ° C. or higher and 165 ° C. or lower.
When the softening temperature of the easy-adhesion layer is 50 ° C. or higher, the strength of the easy-adhesion layer at room temperature is excellent, and cracks or peeling of the printing layer or the metal layer are prevented. On the other hand, when the temperature is 180 ° C. or lower, the temperature is sufficiently softened during thermoforming, the easy-adhesion layer is less likely to crack, and the printing layer and the metal layer, which will be described later, are prevented from cracking or peeling. The softening temperature can be determined, for example, by measuring the flow start temperature with an enhanced flow tester.

(Easy adhesive layer, printing layer)
In one embodiment, the laminate further includes a printed layer (also referred to as a printed matter) laminated on the surface of the easy-adhesive layer opposite to the first resin layer. The shape of the print layer is not particularly limited, and various shapes such as solid, carbon, and wood grain can be mentioned.
The thickness of the print layer is usually 1 to 50 μm.

(Easy adhesive layer, metal layer)
In one embodiment, the laminate further comprises a metal layer laminated on the surface of the easy-adhesive layer opposite to the first resin layer.
The metal layer is a layer containing a metal or a metal oxide. The metal of the metal or the metal oxide is not particularly limited as long as it is a metal that can give a metallic design to the laminate, and for example, tin, indium, chromium, aluminum, nickel, copper, silver, gold, platinum, and zinc. , And alloys containing at least one of these. These may be used alone or in combination of two or more.
Among these, tin, indium and aluminum are preferably mentioned from the viewpoint of extensibility. As a result, cracks are less likely to occur when the laminated body is three-dimensionally molded.

(Manufacturing method of laminated body)
The method for producing the laminate is not particularly limited, but it can be preferably obtained by, for example, quenching the resin composition for forming each layer co-extruded from the T-die into layers at a cooling rate of 80 ° C./sec or more. It will be described in detail below with reference to FIG.

FIG. 1 is a schematic configuration diagram of an example of a manufacturing apparatus for manufacturing the laminate of the present invention. The manufacturing apparatus shown in FIG. 1 includes a T-die 12 of an extruder, a first cooling roll 13, a second cooling roll 14, a third cooling roll 15, a fourth cooling roll 16, and a metal endless belt 17.
An embodiment of a method for manufacturing the laminated body 11 by quenching using the manufacturing apparatus configured as described above will be described below.
The resin composition for forming each layer (first to third resin layers) extruded in layers from the T-die 12 of the extruder is placed on the first cooling roll 13 with the metal endless belt 17 and the fourth cooling roll. It is sandwiched between 16 and 16. In this state, the molten resin is pressure-welded and cooled by the first and fourth cooling rolls 13 and 16.

The temperature of the molten resin extruded from the T-die 12 is, for example, 200 ° C. or higher, and 350 ° C. or lower, for example.
On the other hand, the surface temperatures of the metal endless belt 17 and the fourth cooling roll 16 that come into direct contact with the extruded molten resin and cool the extruded molten resin are controlled to maintain a predetermined temperature. The predetermined temperature is usually above the dew point, for example, 10 ° C. or higher, and for example, 40 ° C. or lower. The temperature of the other cooling rolls 13, 14 and 15 can be appropriately controlled.
Thereby, the cooling rate of the molten resin can be set to, for example, 80 ° C./sec or more, 90 ° C./sec or more, or 150 to 300 ° C./sec or more, whereby the extruded molten resin is rapidly cooled. By performing such quenching, the crystal structure can be made into the above-mentioned Smetika crystal.

During the rapid cooling, the elastic material 22 is compressed and elastically deformed by the pressing force between the first cooling roll 13 and the fourth cooling roll 16. The rapidly cooled laminate 11 is planarly pressure-welded by the cooling rolls 13 and 16 at the portion where the elastic material 22 is elastically deformed, that is, the arc portion corresponding to the central angle θ1 of the first cooling roll 13. .. The surface pressure at this time is usually 0.1 MPa or more and 20 MPa or less.

The laminate 11 which is pressure-welded as described above and sandwiched between the fourth cooling roll 16 and the metal endless belt 17 is subsequently subjected to the metal endless belt at an arc portion corresponding to substantially the lower half circumference of the fourth cooling roll 16. It is sandwiched between the 17 and the 4th cooling roll 16 and subjected to planar pressure contact. The surface pressure at this time is usually 0.01 MPa or more and 0.5 MPa or less.

After surface pressure welding and cooling with the fourth cooling roll 16 in this way, the laminate in close contact with the metal endless belt 17 is moved onto the second cooling roll 14 with the rotation of the metal endless belt 17. Here, the laminated body 11 guided by the peeling roll 21 and pressed toward the second cooling roll 14 has a surface formed by a metal endless belt 17 at an arc portion corresponding to substantially the upper half circumference of the second cooling roll 14, as described above. It is pressure-welded and cooled again at a temperature of 30 ° C. or lower. The surface pressure at this time is usually 0.01 MPa or more and 0.5 MPa or less.

The laminate 11 cooled on the second cooling roll 14 is wound at a predetermined speed by a winding roll (not shown).

In the above description, the case where the first to third resin layers are formed by coextrusion film formation is shown, but the present invention is not limited to this. For example, a separately formed third resin layer may be formed on the second resin layer by a known laminating method such as dry laminating or thermal laminating. Further, the third resin layer may be formed on the second resin layer by a printing method such as gravure printing or screen printing, or may be formed by coating such as roll coating. The method for producing the laminate including the easy-adhesion layer is not particularly limited, and for example, the first to third resin layers and the easy-adhesion layer may be formed by coextrusion, or the first to third resin layers may be formed. An easy-adhesive layer may be formed on the laminated body (main body) containing the resin layer by an arbitrary film forming method such as a coating method, or separately formed on the laminated body (main body) including the first to third resin layers. The easy-adhesion layer may be laminated.

(Molded body and manufacturing method of molded body)
The molded product of the present invention is manufactured by using the laminated body according to the present invention. The molding method for obtaining a molded product is not particularly limited, and examples thereof include in-mold molding, insert molding, coating molding, and vacuum compressed air molding. The laminate according to the present invention is preferably used as a coating material in insert molding and coating molding, and more preferably as a coating material in coating molding, from the viewpoint of better exerting the effects of the present invention.

(In-mold molding)
In-mold molding is a method in which a laminate is placed in a mold and molded into a desired shape by the pressure of a molding resin supplied into the mold to obtain a molded product.
The method for producing a molded product by in-mold molding includes mounting the laminate on a mold and supplying a molding resin to the mold to integrate the laminate and the molding resin. preferable.

(Insert molding)
The manufacturing method of the molded body by insert molding is to attach the laminated body to match the mold (preliminary molding), to attach the attached laminated body to the mold, and to mold the laminated body into the mold. It is preferable to supply the resin for molding and to integrate the laminate and the resin for molding. By insert molding, a more complicated shape can be given to the molded body.
The preliminary forming is preferably performed by, for example, vacuum forming, compressed air forming, vacuum forming, press forming, plug assist forming or the like.

The molding resin used for in-mold molding, insert molding and the like is preferably a moldable thermoplastic resin. Specific examples of such a thermoplastic resin include, but are not limited to, polypropylene, polyethylene, polycarbonate, acrylonitrile-styrene-butadiene copolymer, acrylic polymer and the like. Inorganic fillers such as fiber and talc may be added to the thermoplastic resin.
The molding resin is preferably supplied by injection, preferably at a pressure of 5 MPa or more and 120 MPa or less.
The mold temperature is preferably 20 ° C. or higher and 90 ° C. or lower.

(Coating molding)
The method of manufacturing the molded body by coating molding is to dispose the core material in the chamber box, arrange the laminate above the core material in the chamber box, reduce the pressure in the chamber box, and heat the laminate. It is preferable to include softening and pressing the heat-softened laminate against the core material to cover the core material with the laminate.
At this time, it is preferable to bring the laminate into contact with the upper surface of the core material after heat softening.
For pressing, it is preferable to pressurize the opposite side of the core material of the laminate while reducing the pressure on the side of the laminate in contact with the core material in the chamber box.
The core material may be convex or concave, and examples thereof include resins, metals, and ceramics having a three-dimensional curved surface. Examples of the resin include those similar to those described as the molding resin.

The chamber box used for coating molding is preferably provided with, for example, two upper and lower molding chambers (upper molding chamber and lower molding chamber) that can be separated from each other. An example of coating molding using such a chamber box will be described below.
First, the core material is placed on the table in the lower molding chamber and set. The laminate, which is the object to be molded, is fixed to the upper surface of the lower molding chamber with a clamp. At this time, the pressure inside the upper and lower molding chambers is atmospheric pressure.
Next, the upper molding chamber is lowered, the upper and lower molding chambers are joined, and the inside of the chamber box is closed. Both the upper and lower molding chambers are changed from the atmospheric pressure state to the vacuum suction state by the vacuum tank.
After the upper and lower molding chambers are in a vacuum suction state, the heater is turned on to heat the laminate.
Next, the table in the lower molding chamber is raised while keeping the vacuum state in the upper and lower molding chambers.
Next, by releasing the vacuum in the upper molding chamber and applying atmospheric pressure, the laminate to be molded is pressed against the core material and overlaid (molded).
By supplying compressed air to the upper molding chamber, it is possible to bring the laminate into close contact with the core material with a larger force. After the overlay is completed, the heater can be turned off, the vacuum in the lower molding chamber can be released to return to the atmospheric pressure state, the upper molding chamber can be raised, and the core material (product) covered with the laminate can be taken out.

(Vacuum compressed air molding)
The method for producing a molded product by vacuum pressure air molding preferably includes heating and softening the laminate and shaping the heat-softened laminate into a predetermined mold shape by air pressure.

In the above description, the case where the first resin layer is a clear layer, the second resin layer is a colored layer, and the third resin layer is an adhesive layer has been described, but the present invention is not limited to this. The first to third resin layers may each have an arbitrary function depending on the purpose and application of the laminate.

Examples of the present invention will be described below, but the present invention is not limited to these examples.

Example 1
(1) Material used in Examples and Comparative Examples (Polypropylene resin)
PP-1: "FTX0983" manufactured by Japan Polypropylene Corporation (homopolypropylene having a long-chain branched structure, MFR: 6 g / 10 minutes, branching index 0.96, melt tension 5.4 g)
-PP-2: Polypropylene Polypropylene with a lower isotactic pentad fraction than PP-1, MFR: 7.3 g / 10 minutes, branching index 0.96, melt tension 5.0 g)
-PP-3: "Prime Polypro F133A" manufactured by Prime Polymer Co., Ltd. (Homopolypropylene without long-chain branched structure, MFR: 2.8 g / 10 minutes)
(Nucleating agent)
-Nucleating agent-1: "Rikemaster FC-1" manufactured by RIKEN Vitamin Co., Ltd. (sorbitol-based nucleating agent)
(Colorant)
-Black masterbatch (MB): "PPM 91291 BLACK AL # 315" manufactured by Tokyo Ink Co., Ltd. (MFR: 4.0 g / 10 minutes, base resin: homopolypropylene, pigment: carbon black)
(adhesive)
-Hot melt-1: Low melting point olefin adhesive manufactured by Japan Polypropylene Corporation (MFR: 6 g / 10 minutes, melting point (Tm): 118 ° C)
-Hot melt-2: "Toyomelt ER-6009D" manufactured by Toyo Adre Co., Ltd. (olefin adhesive resin, MFR: 6 g / 10 minutes, melting point (Tm): 98 ° C)
-Hot melt-3: Low melting point olefin adhesive manufactured by Japan Polypropylene Corporation (MFR: 6 g / 10 minutes, melting point (Tm): 127 ° C)

(2) MFR
The MFR of the resin shown in (1) above is a value measured at 230 ° C. and a load of 2.16 kg in accordance with JIS K7210.

(3) Branch index g'
The branching index g'was measured as a function of absolute molecular weight Mabs by using a GPC (gel permeation chromatography measuring device) equipped with a light scatterometer and a viscometer. Specifically, it was measured by the following measuring method and conditions.
(Measurement condition)
-GPC: Alliance GPCV2000 (manufactured by Waters)
-Detector: Described in the order of connection Multi-angle laser light scattering detector (MALS): DAWN-E (manufactured by Waitt Technology)
Differential refractometer (RI): Attached to GPC Viscometer (Viscometer): Attached to GPC-Mobile phase solvent: 1,2,4-trichlorobenzene (BASF Japan Co., Ltd. "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 Corporation are connected. ・ Sample injection part temperature: 140 ° C.
-Column temperature: 140 ° C
・ Detector temperature: All 140 ℃
-Sample concentration: 1 mg / mL
-Injection volume (sample loop volume): 0.2175 mL
(Measuring method)
As the GPC, a GPC device equipped with a differential refractometer and a viscosity detector is used. Further, as the light scattering detector, a multi-angle laser light scattering detector (MALS) is used. The detectors are connected in the order of MALS, RI, and Viscometer. 1,2,4-trichlorobenzene is used as the mobile phase solvent.
The flow rate of the mobile phase solvent is 1 mL / min. The temperature of the column, the sample injection part and each detector is maintained at 140 ° C. The sample concentration is 1 mg / mL, and the injection amount (sample loop volume) is 0.2175 mL. The data processing software ASTRA (version 4.73.04) attached to MALS is used to obtain the absolute molecular weight (Mabs) obtained from MALS, the root mean square radius (Rg), and the limit viscosity ([η]) obtained from Viscometer. ..
The branching index g'is the ultimate viscosity ([η] br) of the long-chain branched polymer (measurement target polymer) obtained by measuring the sample with the above Viscometer and the limit viscosity ([η] br) separately obtained by measuring the linear polymer. It is calculated as a ratio to [η] lin) ([η] br / [η] lin).
Here, as the linear polymer for obtaining [η] lin, commercially available homopolypropylene (Novatec (registered trademark) PP grade name: FY6 manufactured by Japan Polypropylene Corporation) is used. Since it is known as the Mark-Houwink-Sakurada formula that the logarithm of [η] lin of a linear polymer has a linear relationship with the logarithm of molecular weight, [η] lin is appropriately set on the low molecular weight side or the high molecular weight side. The numerical value can be obtained by extrapolation. The branching index g'is a value when the absolute molecular weight (Mabs) is 1,000,000.

(4) Melt tension The melt tension was measured as follows. That is, using a capillograph, polypropylene used in the first resin layer was placed in a cylinder having a diameter of 9.6 mm heated to a temperature of 230 ° C. The molten resin was extruded from an orifice having a diameter of 2.0 mm and a length of 40 mm at a pushing speed of 20 mm / min. The tension detected by the pulley when the extruded resin was taken up at a speed of 4.0 m / min was measured and used as the melt tension.

(5) Method for measuring isotactic pentad fraction The isotactic pentad fraction was measured by evaluating the ^{13 C-NMR spectrum of the polypropylene used.} Specifically, it was carried out under the following conditions according to the peak attribution proposed in "Macromopolymers, 8, 687 (1975)" by A. Zambali et al.
(Measurement method / conditions)
Equipment: JNM-EX400 type ¹³ C-NMR equipment manufactured by JEOL Ltd. Method: Proton complete decoupling method Concentration: 220 mg / ml
Solvent: 90:10 (volume ratio) mixture of 1,2,4-trichlorobenzene and heavy benzene Solvent temperature: 130 ° C
Pulse width: 45 °
Pulse repetition time: 4 seconds integration: 10000 times (calculation formula)
Isotactic pentad fraction [mmmm] = m / S x 100
Racemic pentad fraction [rrrr] = γ / S × 100
Racemic racemic racemic mesopentad fraction [rmrm] = Pββ + Pαβ + Pαγ
S: Signal intensity of side chain methyl carbon atom of all propylene units Pββ: 19.8 to 22.5 ppm
Pαβ: 18.0 to 17.5 ppm
Pαγ: 17.5 to 17.1 ppm
γ: Racemic pentad chain: 20.7 to 20.3 ppm
m: Mesopentad chain: 21.7 to 22.5 ppm

(6) Film forming conditions Using the same manufacturing equipment as that shown in FIG. 1, the first resin layer (clear layer) / second resin layer (colored layer) / third resin layer (adhesive layer) A laminate consisting of three layers was produced by a coextrusion method.
The manufacturing conditions of the laminate are as follows.
-Laminating method: Coextrusion lamination (distributor method)
-Thickness of each layer of the laminate: as shown in Table 1.-Components and composition of each layer of the laminate: as shown in Table 1.-Diameter of the extruder of the first resin layer: 65 mm.
-Diameter of the extruder of the second resin layer: 75 mm
-Diameter of the extruder of the third resin layer: 50 mm
・ T-die width: 900 mm
・ Take-up speed of laminated body: 5 m / min ・ Surface temperature of cooling roll and metal endless belt: 20 ℃
-Cooling rate: 10,800 ° C / min (180 ° C / sec)

(7) Crystal structure (crystal form)
T. The measurement was carried out with reference to the method used by Konishi et al. (Macropolymers, 38, 8749, 2005).
In the analysis, the peaks of the amorphous phase, the intermediate phase, and the crystalline phase were separated from each other for the X-ray diffraction profile, and the abundance ratio was determined from the peak area assigned to each phase. The "Smetica crystal" and "α crystal" shown in Table 1 are crystal forms showing the largest peak area.

(8) Volume Fraction of Spherulite When it is confirmed by the measurement of (7) that the resin layer contains spherulite, the volume fraction of spherulite having a diameter of 1 μm to 10 μm in the resin layer is as follows. Calculated by the method.
That is, after cutting only the resin layer (here, the first resin layer) to be measured on the sheet with "SAICAS (registered trademark) DN-20S" manufactured by Daipla Wintes Co., Ltd. by about 120 μm, this resin piece is cut into small angles. The average radius of spherulites in the first resin layer was calculated by measuring by a light scattering method. Further, the average volume of spherulite and the volume of the non-spherulite portion were calculated by measuring the number of spherulite in the cross section of the resin layer with a polarizing microscope, and the volume fraction of spherulite was calculated from these values.
In the small-angle light scattering method, a He-Ne gas laser (wavelength 632.8 nm, output 5 mW, manufactured by NEC Corporation) was used as irradiation light, and a sample (deposited resin layer) was irradiated through a polarizer. The sample transmitted light was applied to an imaging plate (Neopan Preso400, manufactured by FUJIFILM Corporation) via an analyzer. Based on the following formula, the average radius R of spherulites inside the sheet was calculated from the irradiation image.
R = 4.09 / Q _max (R: average radius of spherulites, Q _max : scattering vector that maximizes scattering intensity)
Q = 4πn / λ (Q: scattering vector, n: refractive index, λ: incident light wavelength)
Next, the cross section of the resin layer was prepared with a microtome (manufactured by Thermo Fisher Scientific Co., Ltd., HM340E) and sliced to a thickness of 10 μm to obtain a resin layer piece. A resin layer piece was placed on the slide glass and covered with a cover glass. Then, the cross section of the resin layer was observed with a polarizing microscope (ECLIPSE LV100N manufactured by Nikon Corporation). Martese cloth is observed at the site where spherulites are formed. The number of spherulites having a diameter of 1 μm to 10 μm is measured from a cross-sectional observation image (a square region defined by the thickness of the first resin layer (μm) at the time of film formation × the thickness of the first resin layer (μm) at the time of film formation). did. The spherulites that are not exposed on the outermost surface can be observed by adjusting the focal position of the polarizing microscope in the thickness direction from the outermost surface of the resin layer.
And spherulites average volume (= 4πR ^3/3) calculated from spherulite mean radius R, the product of the number of spherulites having a diameter of 1 [mu] m ~ 10 [mu] m, and the average volume of spherulite diameter 1 [mu] m ~ 10 [mu] m.
After calculating the average volume of spherulite having a diameter of 1 μm to 10 μm and the volume of the non-spherulite portion, the volume fraction of the spherulite having a diameter of 1 μm to 10 μm in the first resin layer is obtained from these volume ratios. It was.

(9) Crystallization rate The crystallization rate was measured using a differential scanning calorimetry device (DSC) (manufactured by PerkinElmer, product name "Diamond DSC"). Specifically, first, 5 mg of a sample was prepared using polypropylene used in each of the first resin layer and the second resin layer, and the sample was changed from 50 ° C. to 230 ° C. at 10 ° C./min. The temperature was raised, held at 230 ° C. for 5 minutes, cooled from 230 ° C. to 130 ° C. at 80 ° C./min, and then held at 130 ° C. for crystallization. The measurement of the change in calorific value was started from the time when the temperature reached 130 ° C., and the DSC curve was obtained.
From the obtained DSC curve, the crystallization rate was determined by the following procedures (i) to (iv).
(I) The baseline was the linear approximation of the change in calorific value from the time point 10 times the time from the start of measurement to the peak top to the time point 20 times.
(Ii) The intersection of the tangent line having a slope at the inflection point of the peak and the baseline was obtained, and the crystallization start and end times were obtained.
(Iii) The time from the obtained crystallization start time to the peak top was measured as the crystallization time.
(Iv) The crystallization rate was determined from the reciprocal of the obtained crystallization time.

(10) Low temperature side exothermic peak In the DSC curve of the above "(9) Crystallization rate", the presence or absence of an exothermic peak (also referred to as "low temperature side exothermic peak") on the low temperature side of the maximum endothermic peak is observed, and the exothermic peak is When observed, the calorific value (J / g) was calculated according to the transition heat calculation method described in JIS K7122: 2012 (transition heat measurement method).

(11) Measurement of melting point and melting enthalpy of adhesive raw material The melting point of the resin (adhesive raw material) used for the third resin layer was determined in accordance with JIS K7121: 2012 (transition temperature measurement method). The melting enthalpy of the adhesive raw material used for the third resin layer was determined according to the method described in JIS K7122 (method for measuring transition heat).

(12) Drawdown amount The measurement was carried out by the following method using a coating molding machine "NGF-0611-S" manufactured by Fuse Vacuum Co., Ltd.
The sheet was cut into 1150 mm × 650 mm to obtain a test sheet. The test sheet was clamped to a 1100 mm × 600 mm molding frame. The molding frame is provided with a scale for reading the amount of sagging during drawdown.
The molding frame to which the test sheet was fixed was set in the chamber box (including the upper molding chamber and the lower molding chamber) of the coating molding machine. In the set state, the test sheet is oriented so that the main surface of the test sheet is horizontal. Further, the scale is oriented so that the scale direction of the scale is the vertical direction.
Next, the inside of the chamber box was evacuated by a vacuum pump. When the pressure in the chamber box reached 20 kPa, the test sheet was heated by a heater (manufactured by HERAEUS, a medium wavelength band infrared heater (200 W, 115 V)) arranged in the upper molding chamber. The heater was arranged so that the heater surface that radiates infrared rays in the middle wavelength band was parallel to the main surface of the test sheet. The output (output%) of the heater was set to be the value shown in FIG. 2 for each of the 13 categories of the test sheet. For example, in the category shown as "80%" in FIG. 2, the output of the heater is set to 200 W x 80% = 160 W.
The depressurization by the vacuum pump and the heating by the heater were further continued, and the state until the sheet was drawn down and re-tensioned by the heating was recorded by a video camera installed outside the window of the upper molding chamber. At this time, the vacuum pump was driven so that the maximum degree of vacuum in the chamber box reached less than 0.1 kPa. In addition, the scale installed on the molding frame was photographed by the video camera.
The drawdown image of the sheet was compared with the scale shot image, and the amount of sagging at the maximum drawdown of the sheet was read and used as the drawdown amount (maximum drawdown amount).

(13) Wrinkle prevention property A half bumper injection molded product (length 95 cm x width 26 cm x height) after the surface temperature of the sheet reaches 140 ° C. using the same coating molding machine as in "(12) Drawdown amount" above. A sheet (thickness 0.3 mm) was coated and molded on (13 cm) to obtain a molded product. The surface texture of the sheet coated and molded on the half bumper was visually observed, and the wrinkle prevention property was evaluated according to the following evaluation criteria.
[Evaluation criteria]
◯: There are no wrinkles on the sheet covered with the half bumper.
Δ: The sheet coated on the half bumper has no unevenness, but has a streaky appearance change.
X: Wrinkles are generated on the sheet coated on the half bumper, and convex portions are formed in a streak pattern.

(14) Deep drawing property With respect to the molded product obtained in the above "(13) Wrinkle prevention property", the presence or absence of holes and the sheet thickness at the maximum depth (13 cm) of the half bumper where the sheet is most stretched were observed. The deep drawing property was evaluated according to the following evaluation criteria.
[Evaluation criteria]
◯: There are no holes in the sheet, and the sheet thickness is 80 μm or more.
Δ: There are no holes in the sheet, but the sheet thickness is less than 80 μm.
X: There is a hole in the sheet.

(15) Anti-whitening property With respect to the molded product obtained in the above "(13) Anti-wrinkle property", the surface texture of the sheet coated and molded on the half bumper is visually observed, and the anti-whitening property is evaluated according to the following evaluation criteria. did.
[Evaluation criteria]
◯: No whitening due to stretching is observed on the sheet.
X: Whitening due to stretching is observed on the sheet.

(16) Change in surface gloss Using a coating molding machine similar to the above "(12) Drawdown amount", the laminate was coated and molded into a 4-fold stretched mold. The surface gloss of the laminate before and after molding was measured using a gloss meter (“VG-2000” manufactured by Nippon Denka Kogyo Co., Ltd.) by a method based on “Method 3” in JIS-Z-8741: 1997. .. The change in surface gloss was determined by reducing the surface gloss after molding from the surface gloss before molding.

(17) Color difference measurement Using the same coating molding machine as in the above "(12) Drawdown amount", the sheet was coated and molded into a 4-fold stretch mold. For the sheets before and after molding, using a colorimeter (“CM-2600d” manufactured by Konica Minolta Co., Ltd.), the color difference ΔE (L ^* a ^* b ^{*) is based on the spectrophotometric method of JIS-Z-8730: 2009.} Color system) was measured.

(18) Adhesion strength measurement Using a coating molding machine similar to the above "(12) Drawdown amount", the laminate was made of homopolypropylene (Prime Polymer J106G) injection molded flat plate (length 150 mm x width 70 mm x thickness). 3 mm) was coated and molded. The coating molding conditions are as follows.
-Molding frame size: 1100 mm x 600 mm
-Laminate cut size: 1150 mm x 650 mm
-Laminate body surface temperature during molding: 140 ° C
・ Chamber box vacuum during molding: less than 0.1 kPa ・ Upper molding chamber compressed air pressure during molding: 210 kPa
・ Compressed air time: 15s
Then, a notch was made in the laminate with a 15 mm wide cutter, and a grip margin was manually made in the 15 mm notch. After fixing the grip margin to a jig of a push-pull gauge (manufactured by IMADA), the laminate was peeled 50 mm from the injection molded product in the 180 ° direction with respect to the contact surface. The adhesion strength (N / 15 mm) was determined from the value displayed on the push-pull gauge.

Examples 2 and 3
A laminate was prepared and evaluated in the same manner as in Example 1 except that the components and compositions of each layer of the laminate were as shown in Table 1.

Comparative Examples 1 to 3
The components and compositions of each layer of the laminate are as shown in Table 1, and the surface temperature of the cooling roll and the metal endless belt is 80 ° C., and the cooling rate is 1,154 ° C./min. A laminate was prepared and evaluated in the same manner.

Comparative Example 4
A laminate was prepared and evaluated in the same manner as in Example 1 except that the components and compositions of each layer of the laminate were as shown in Table 1.

The above results are shown in Table 1.

The molded product obtained from the laminate of the present invention can be used for a wide variety of applications, for example, a housing in a wide range of fields such as transportation equipment (automobiles, motorcycles, etc.), housing equipment, building materials, home appliances, and the like. It can be used as a decorative sheet to replace painting on the body.

Although some embodiments and / or embodiments of the present invention have been described above in detail, those skilled in the art will be able to demonstrate these embodiments and / or embodiments without substantial departure from the novel teachings and effects of the present invention. It is easy to make many changes to the examples. Therefore, many of these modifications are within the scope of the invention.
All the documents described in this specification and the contents of the application on which the priority under the Paris Convention of the present application is based are incorporated.

Claims (16)

1. A laminate containing a first resin layer, a second resin layer, and a third resin layer in this order.
   The first resin layer and the second resin layer contain polypropylene, each of which has a long-chain branched structure and a crystallization rate at 130 ° C. of 2.5 min ^-1 or less. ,
   The composition of the first resin layer and the second resin layer are different.
   The third resin layer contains an adhesive having a melting point of 125 ° C. or lower.
   Laminated body.
2. The adhesive of the third resin layer is one or more selected from the group consisting of an olefin-based adhesive, a styrene-based adhesive, an isocyanate-based adhesive, a urethane-based adhesive, and an acrylic-based adhesive. Item 1. The laminated body according to Item 1.
3. The laminate according to claim 1 or 2, wherein the second resin layer contains a pigment.
4. Polypropylene of one or more resin layers selected from the group consisting of the first resin layer and the second resin layer is 1 J / g or more on the low temperature side of the maximum endothermic peak in the curve obtained by differential scanning calorimetry. The laminate according to any one of claims 1 to 3, which has an endothermic peak.
5. The laminate according to any one of claims 1 to 4, wherein the polypropylene of one or more resin layers selected from the group consisting of the first resin layer and the second resin layer contains smetica crystals.
6. The laminate according to claim 5, wherein spherulites having a diameter of 1 μm to 10 μm are present in one or more of the resin layers containing the smetika crystals, and the volume fraction of the spherulites in the resin layer is 20% or less. body.
7. Claims 1 to 6, wherein the polypropylene isotactic pentad fraction of one or more resin layers selected from the group consisting of the first resin layer and the second resin layer is 85 to 99 mol%. The laminate according to any one.
8. Any of claims 1 to 7, wherein the polypropylene branching index of one or more resin layers selected from the group consisting of the first resin layer and the second resin layer is 0.50 or more and less than 1.00. The laminate described in.
9. The laminate according to any one of claims 1 to 8, wherein the polypropylene melt tension of one or more resin layers selected from the group consisting of the first resin layer and the second resin layer is 4.0 g or more. body.
10. The laminate according to any one of claims 1 to 9, further comprising an easy-adhesion layer.
11. The laminate according to claim 10, wherein the easy-adhesion layer contains one or more resins selected from the group consisting of urethane, acrylic, polyolefin, and polyester.
12. The laminate according to claim 10 or 11, further comprising a print layer laminated on the surface of the easy-adhesion layer opposite to the first resin layer.
13. A molded product manufactured by using the laminate according to any one of claims 1 to 12.
14. A method for producing a molded body, which comprises molding the laminate according to any one of claims 1 to 12 to obtain a molded body.
15. A claim that the laminated body is shaped so as to match a mold, the shaped laminated body is mounted on a mold, a molding resin is supplied, and the molded laminated body is integrated with the shaped laminated body to perform the molding. Item 14. The method for producing a molded product according to Item 14.
16. The core material is arranged in the chamber box, the laminated body is arranged above the core material, the laminated body is heated and softened, and the inside of the chamber box is depressurized to heat and soften the laminated body. The method for producing a molded body according to claim 14, wherein the material is pressed and covered.

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