JP2007030424A - Laminated sheet for package and package formed by the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laminated sheet for a package which is excellent in balance among transparency, rigidity, and impact resistance, and excellent in design when printing is applied, and foldable creasing work property, and the package formed by the laminated sheet for packaging. <P>SOLUTION: In the laminated sheet having an intermediate layer and outer layers laminated on both surfaces, the intermediate layer is a polypropylene film which is A component, and mainly composed of polypropylene resin having a crystal melting heat quantity (ΔHm) of 70 to 120 J/g obtained from a thermogram at a heating speed of 10°C/min by a differential scanning calorimeter (DSC), and the outer layer is a biaxially oriented polypropylene film. A printing layer is provided on the side laminated on the intermediate layer in at least one side of outer layer. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a laminated sheet for a printed package and a package formed from the sheet, and more particularly to a laminated sheet for a package having good printing design and a package formed from the sheet.

  Conventionally stores cosmetics, stationery, medical products, electrical accessories such as audio accessories and parts, sports equipment, toys, toiletries, kitchenware, air fresheners, accessories, textile products, hobby goods, travel goods, hobby goods, etc. The transparent package (transparent case) is printed on one side of a transparent sheet with images and advertising characters, punched into a flat shape suitable for forming the final shape, and at this time, a folding ruled line is formed simultaneously or in a separate process And it is shape | molded by bend | folding with this bending ruled line, and making it the target shape.

  A sheet for forming a transparent package is sometimes abbreviated as rigid polyvinyl chloride (hereinafter referred to as “PVC”) because of its excellent secondary processability, transparency, economy, productivity, and the like. ) Sheets have been used. However, the PVC sheet generates hydrogen chloride gas, which is a harmful substance during combustion, thereby damaging the incinerator and causing problems such as environmental pollution. Therefore, a non-PVC material is demanded, and among them, a sheet using a polypropylene resin is used because it is excellent in low cost, heat resistance and mechanical strength.

  However, with a sheet using a conventional polypropylene resin, it is difficult to obtain a sheet with good transparency, and it is difficult to obtain a clear feeling when printing is performed on the case. In addition, the printed surface may be scratched or the print may be peeled off, which may impair the design. In addition, in order to use as a case, not only transparency but also rigidity and impact resistance are necessary, and it is necessary to have an excellent balance in these properties, and a conventional polypropylene resin composition was used. In the sheet, it was difficult to make these properties excellent in balance.

  For these problems, it is conceivable to laminate a non-stretched polypropylene film (hereinafter sometimes abbreviated as “CPP” film) printed on a polypropylene sheet. This improves the glossiness of the sheet, and by bringing the printing surface to the inner surface of the sheet and the CPP film, it is thought that scratches on the printing surface, peeling of printing, etc. can be suppressed. I can't hope.

  Patent Document 1 describes a packaging polypropylene sheet in which petroleum resins are blended with a polypropylene resin.

  Patent Document 2 describes a method for producing a polypropylene resin sheet in which a resin composition comprising a polypropylene resin, a petroleum resin, and an ethylene-α-olefin copolymer is extruded into a sheet shape.

  Patent Document 3 describes a polypropylene laminated sheet obtained by laminating a biaxially stretched polypropylene film on a polypropylene sheet having a smectic crystal structure.

  Patent Document 4 describes a sheet in which a stretched film made of a crystalline propylene polymer is laminated on at least one side of a polypropylene sheet.

Patent Document 5 describes a transparent polypropylene sheet and a method for producing the same with the object of providing a transparent polypropylene sheet having impact resistance and rigidity while ensuring transparency.
JP 59-143613 A Japanese Patent Publication No. 6-89191 JP-A-3-2888641 JP 10-291284 A JP 2003-170485 A

  However, in the sheet described in Patent Document 1, improvement in transparency and rigidity can be expected, but on the other hand, the sheet becomes brittle, and the sheet is cracked when performing secondary processing such as punching or bending ruled line processing. There was a case.

  Moreover, in the method described in Patent Document 2, although the impact resistance is improved, the rigidity of the sheet is reduced, the rigidity (waist) is insufficient when used as a case for packaging, and the scratch resistance of the sheet is also reduced. However, when it is used as a case for packaging, there may be a practical problem that the surface of the case is damaged and the appearance is impaired. Furthermore, in order to improve the transparency of the sheet, a water-cooled cooling device is used, and there are restrictions on facilities.

  In addition, the laminated sheet described in Patent Document 3 mainly improves the drawdown property during thermoforming, and there is still room for improvement in terms of transparency and rigidity of the laminated sheet. In addition, since it is a two-layer laminated sheet in which a biaxially stretched polypropylene film is bonded only on one side, when the sheet containing petroleum resin is subjected to secondary processing such as bending ruled line processing, cracking or the like occurs in the sheet. There was a case.

  In addition, the laminated sheet described in Patent Document 4 is also mainly an improved drawdown property at the time of thermoforming, and the area stretch ratio of the stretched film is specified in order to improve the thermoformability. There was still room for improvement because of its limited rigidity.

  Moreover, in the manufacturing method described in Patent Document 5, special devices and processes such as a metal endless belt are required when forming a sheet using polypropylene, and there are restrictions on facilities.

  As described above, with a sheet using a conventional polypropylene-based resin, it is difficult to obtain a sheet having an excellent balance in transparency, rigidity, and impact resistance, and there are restrictions on facilities. In addition, when a conventional sheet is used as a package, it is difficult to obtain a clear feeling when printing is performed on the inner surface, and the inner surface (printed surface) is scratched by rubbing with the stored items, impact, etc. There has been a problem that the designability may be impaired due to printing or peeling of printing.

  Then, this invention makes it a subject to provide the laminated sheet for packaging bodies which was excellent in the balance in transparency, rigidity, and impact resistance, and was excellent in the designability at the time of printing, and the bending ruled line workability.

  The present invention will be described below. In order to facilitate understanding of the present invention, reference numerals in the accompanying drawings are appended in parentheses, but the present invention is not limited to the illustrated embodiment.

  As a result of intensive studies, the present inventors have found that at least one biaxially stretched polypropylene in a laminated sheet in which an outer layer composed of a biaxially stretched polypropylene film is laminated on both surfaces of an intermediate layer composed of a polypropylene resin composition. The present invention has been completed by finding that the above-mentioned problems can be solved by adopting a configuration in which a printing layer is provided on the side laminated with the intermediate layer in the system film.

1st this invention is a laminated sheet which has an intermediate | middle layer (10) and the outer layer (20) laminated | stacked on both surfaces, Comprising: An intermediate | middle layer (10) is a polypropylene film which has the following A component as a main component In the laminated sheet (100) for a packaging body, the outer layer (20) is a biaxially stretched polypropylene film and has a printed layer (30) on the side laminated with the intermediate layer (10) in at least one outer layer (20). is there.
Component A: Polypropylene resin having a crystal melting heat (ΔHm) of 70 to 120 J / g determined from a thermogram obtained by a differential scanning calorimeter (DSC) at a heating rate of 10 ° C./min.

In the laminated sheet for package (100), the intermediate layer (10) further has the following B component, and the mass ratio of the A component to the B component is “95: 5” to “60:40” ( A component: B component) is preferable.
Component B: at least one resin selected from the group consisting of petroleum resins, terpene resins, coumarone-indene resins, rosin resins, and hydrogenated derivatives thereof.

  In said laminated sheet (100) for packaging bodies, an intermediate | middle layer (10) has a crystal nucleating agent as C component further, and the compounding quantity is 0.05-1. It is preferably 00 parts by mass.

  In the laminated sheet for packaging body (100), the ratio of the thickness of the intermediate layer (10) to the entire thickness of the laminated sheet for packaging body (100) is preferably 0.30 to 0.98.

  2nd this invention is a package formed by said laminated sheet (100) for package bodies.

  According to the present invention, by laminating an outer layer made of a biaxially stretched polypropylene film on which printing has been performed on both surfaces of an intermediate layer made of a specific polypropylene resin composition, transparency, rigidity, and impact resistance are improved. It is possible to provide a laminated sheet for a packaging body which is excellent in balance, excellent in design properties when printed, and excellent in folding ruled line workability, and also formed by this laminated sheet for packaging body. A package having performance can be provided.

  Hereinafter, the present invention will be described based on embodiments shown in the drawings.

  As shown in FIG. 1, the laminated sheet 100 for packaging body of this invention has the outer layer 20 on both surfaces of the intermediate | middle layer 10, and has the printing layer 30 in the side laminated | stacked with the intermediate | middle layer 10 in at least one outer layer 20. As shown in FIG. is doing. In FIG. 1, as an embodiment of the layer structure of the laminated sheet 100 for a packaging body of the present invention, the outer layer 20 </ b> A and the outer layer 20 </ b> B are provided, and the printed layer 30 is provided on the outer layer 20 </ b> A on the side laminated with the intermediate layer 10. The provided configuration is shown.

  By adopting such a layer structure, it is possible to provide excellent printing design and impact resistance, and to impart folding ruled line workability. Further, improvement in rigidity, surface smoothness, surface gloss, scratch resistance and the like can be desired.

<Outer layer 20>
The outer layer 20 in the laminated sheet 100 for a packaging body of the present invention is a biaxially stretched polypropylene film, and is laminated on both surfaces of the intermediate layer 10 directly or via a printing layer 30.

  The outer layer 20 can be manufactured by using a known method described in, for example, Japanese Patent Publication No. 41-21790, Japanese Patent Publication No. 45-37879, Japanese Patent Publication No. 49-18628.

  A biaxially stretched polypropylene film produced by a general-purpose longitudinal-transverse biaxial stretching method is generally obtained by stretching about 4 to 7 times in the longitudinal direction and about 8 to 12 times in the transverse direction. The area stretch ratio is about 30 to 80 times. In order to improve the rigidity when the biaxially stretched polypropylene film used in the present invention is the laminated sheet 100 for a package, it is preferable to use a biaxially stretched polypropylene film having a high stretch ratio and a rigidity as high as possible. The area stretch ratio is preferably 30 times or more, and more preferably 40 times or more.

  Further, the outer layer 20 may be provided with heat sealability on at least the side of the film laminated with the intermediate layer 10 in order to increase the adhesive strength with the intermediate layer 10. As a method for imparting heat sealability, for example, a low-melting-point propylene / ethylene copolymer is laminated on one side or both sides of the outer layer 20 made of a biaxially stretched polypropylene film (Japanese Patent Publication No. 49-14343). A specific propylene random copolymer layer as a heat seal layer (Japanese Patent Publication No. 8-5174), a specific propylene / 1-butene random copolymer and a crystalline propylene / α-olefin random copolymer, Many known methods such as a composite film obtained by laminating the above composition (Japanese Patent Publication No. 61-42626), a method of laminating a resin having a lower melting point than polypropylene, and the like can be appropriately used.

  Moreover, it is preferable that the thickness of the outer layer 20 is 5-100 micrometers normally, It is more preferable that it is 10-70 micrometers, It is further more preferable that it is 20-60 micrometers. Here, if the thickness of the outer layer 20 is too thin, it may not be possible to provide the desired impact resistance and folding ruled line workability desired in the present invention. On the other hand, if the thickness of the outer layer 20 is too thick, it may be difficult to obtain a film with good thickness accuracy, or it may be difficult to obtain a film with good transparency.

<Print layer 30>
The print layer 30 is provided on at least one of the outer layers 20 on the side laminated with the intermediate layer 10. In FIG. 1, the printed layer 30 is provided on the side of the outer layer 20A that is laminated with the intermediate layer 10, but the printed layer 30 may be provided on the side of the outer layer 20B that is laminated with the intermediate layer 10, or the outer layer 20A and It is also possible to provide a configuration in which the printing layer 30 is provided on both of the outer layer 20 </ b> B and the side to be laminated, and the two printing layers 30 are provided. As described above, a complicated design, which is difficult to apply by conventional single-sided printing, is configured by having two layers of printing layers 30 and printing different characters or colors in the two layers of printing layers 30. Can also be granted.

  The print layer 30 can be formed by printing on a biaxially stretched polypropylene film that is the outer layer 20. As a printing method, for example, a known method such as gravure printing, letterpress printing, flat plate printing, intaglio printing, stencil printing, flexographic printing, or the like is used. Moreover, as a pre-printing process, it is preferable to perform a corona discharge process on the surface of the outer layer 20 on which the printing layer 30 is formed.

<Intermediate layer 10>
The intermediate layer 10 in the laminated sheet 100 for a packaging body of the present invention is a polypropylene film having an A component as a main component, and may further have a B component and / or a C component. Hereinafter, the A component, the B component, and the C component will be described.

(A component)
The component A is preferably a polypropylene resin having a heat of crystal melting (ΔHm) of 70 to 120 J / g determined from a thermogram obtained by a differential scanning calorimeter (DSC) at a heating rate of 10 ° C./min. More preferred is a polypropylene resin having a ΔHm of 80 to 120 J / g, and further preferred is a polypropylene resin having a ΔHm of 90 to 120 J / g. When the amount of heat of crystal fusion (ΔHm) is too small, the crystallinity of the polypropylene resin is lowered, the rigidity of the entire laminated sheet 100 is lowered, and the rigidity (waist) is insufficient when used as a package. Problems may arise. On the other hand, the heat of crystal melting (ΔHm) of generally available polypropylene resins is within the above range, and those having a crystal heat of fusion (ΔHm) that is too large may be difficult to obtain industrially.

  Here, the polypropylene resin is a polypropylene homopolymer, a copolymer of propylene and an α-olefin such as ethylene, butene, hexene, or a mixture thereof.

  The intermediate layer 10 is mainly composed of the component A, and preferably contains 60% by mass or more, and 70% by mass or more, based on the mass of the entire intermediate layer (100% by mass). It is more preferable that the content is 80% by mass or more.

  The crystal melting peak temperature (Tm) of the polypropylene resin as the component A is preferably 120 to 175 ° C, more preferably 130 to 175 ° C, and further preferably 140 to 175 ° C. If the crystal melting peak temperature is too low, it may not be satisfactory in terms of rigidity when used as a package. On the other hand, the heat of crystal melting (ΔHm) of generally available polypropylene resins is within the above range, and those too large may be difficult to obtain industrially.

  The melt flow rate (MFR) according to JIS K 7210 (measurement temperature 230 ° C., load 21.18 N) in the polypropylene resin as the component A is preferably 0.50 to 20 g / 10 min, and 1.0 to 10 g. More preferably, it is / 10 min. If the melt flow rate is too small, the discharge amount from the extruder may be reduced during melt molding, and productivity may be lowered. On the other hand, if it is too large, the viscosity may be too low and sheet molding may be difficult.

  The polymerization method for obtaining the polypropylene resin as the component A is not particularly limited, and for example, a known method such as a solvent polymerization method, a bulk polymerization method, or a gas phase polymerization method can be employed. The polymerization catalyst is not particularly limited, and for example, a known catalyst such as a titanium trichloride type catalyst, a magnesium chloride supported catalyst, a metallocene catalyst, etc. can be adopted.

(B component)
In order to improve the transparency and rigidity of the laminated sheet 100 for a package, the intermediate layer 10 includes a petroleum resin, a terpene resin, a coumarone-indene resin, a rosin-based resin, and hydrogen thereof, as a B component together with the A component. It is preferable to contain at least one resin selected from the group consisting of additive derivatives (hereinafter sometimes collectively referred to as “petroleum resins”).

  Examples of the petroleum resin include an alicyclic petroleum resin obtained by polymerizing cyclopentadiene or a dimer thereof, and an aromatic petroleum resin obtained by polymerizing a C9 component. Examples of the terpene resin include a terpene-phenol resin obtained by polymerizing β-pinene. Examples of rosin resins include rosin resins such as gum rosin and wood rosin, and esterified rosin resins modified with glycerin, pentaerythritol, and the like.

  The softening point of petroleum resins as the component B is preferably 70 to 150 ° C, and more preferably 90 to 150 ° C. If the softening point of the petroleum resin is too low, it may not be possible to improve the rigidity desired in the present invention when used as a package, and blocking may occur. On the other hand, if the softening point of the petroleum resins is too high, the compatibility with the component A is deteriorated, and there may be a problem that the transparency of the intermediate layer 10 is lowered.

  In the intermediate layer 10, the petroleum resin as the B component having the preferable softening point exhibits relatively good compatibility when mixed with the polypropylene resin as the A component. Among them, since the color tone, thermal stability, compatibility and the like are particularly good, it is preferable to use petroleum resin or terpene resin as the petroleum resin as the B component.

  In the intermediate layer 10 of the present invention, by mixing petroleum resins as the B component, the glass transition temperature of the polypropylene resin as the A component can be increased, and finally obtained for the packaging body of the present invention. The rigidity (waist) in the normal temperature range of the laminated sheet 100 can be increased. Moreover, by mixing petroleum resins, the crystallization speed of the polypropylene resin that is the component A can be reduced, and the transparency of the package sheet 100 of the present invention can be improved.

  The mass ratio of the A component and the B component in the intermediate layer 10 is preferably “95: 5” to “60:40” (“A component: B component”), and “90:10” to “ 65:35 ”(“ A component: B component ”) is more preferable, and“ 85:15 ”to“ 70:30 ”(“ A component: B component ”) is even more preferable. If the blending amount of petroleum resin as the B component is too large, the rigidity and transparency can be improved, but the impact resistance is deteriorated, so that a problem occurs such that the sheet is cracked during folding and folding. In some cases, since the melt viscosity is low, extrusion molding may not be performed satisfactorily. On the other hand, if the blending amount of petroleum resin as the component B is too small, it may not be possible to improve the rigidity of the manufactured laminated sheet 100 for a package in the normal temperature range.

(C component)
Moreover, in order to further improve the transparency and rigidity of the laminated sheet 100 for packaging bodies, the intermediate layer 10 may contain a crystal nucleating agent as the C component. The crystal nucleating agent is not particularly limited, and a known crystal nucleating agent can be used. For example, 1,3,2,4- (dimethylbenzylidene) sorbitol, sorbitols such as 1,3,2,4-dibenzylidenesorbitol, di- (aluminum para-t-butylbenzoate), bis (4 Metal salts such as (t-butylphenyl) sodium, inorganic crystal nucleating agents such as silica and talc, and the like. Of these, crystal nucleating agents of sorbitols and metal salts are preferable.

  The compounding amount of the crystal nucleating agent is preferably 0.05 to 1.00 parts by mass and more preferably 0.05 to 0.50 parts by mass with respect to 100 parts by mass of the component A. If the blending amount of the crystal nucleating agent is too small, the effect of improving the transparency of the intermediate layer 10 may not be sufficient. On the other hand, if the amount of the crystal nucleating agent is too large, it is not only economically disadvantageous, but conversely, the transparency of the intermediate layer 10 may deteriorate.

<The manufacturing method of the laminated sheet 100 for packaging bodies>
Next, the manufacturing method of the laminated sheet 100 for packaging bodies of this invention is demonstrated. The laminated sheet 100 for a packaging body of the present invention is formed of a biaxially stretched polypropylene film by extruding in a molten state the component A to be the intermediate layer 10 or a mixture of the component A and component B and / or component C. Extrusion in which the outer layer 20 (the outer layer 20 has a printing layer 30 on the side laminated with the intermediate layer 10 in at least one outer layer 20. The same applies hereinafter) is laminated on both sides of the extruded intermediate layer 10 simultaneously with casting. It can be manufactured by a laminating method. When the print layer 30 is formed on the outer layer 20, the outer layer 20 and the intermediate layer 10 are laminated such that the print layer 30 side becomes the intermediate layer 10 side. Further, after the intermediate layer 10 is formed into a sheet by a known method, the outer layer 20 made of a biaxially stretched polypropylene film is thermally laminated on both surfaces of the sheet of the intermediate layer 10, a dry lamination method for dry lamination, etc. It can manufacture by the method of.

  The above resin mixture to be the intermediate layer 10 may be pre-compounded in advance using a same-direction twin-screw extruder, a kneader, a Henschel mixer, etc., or each raw material is dry blended and directly into a melt kneading extruder. You may throw it in. The viscosity of the resin mixture is adjusted by the mixing ratio of the component A polypropylene resin and the component B petroleum resin.

  A specific example of the sheet forming method for forming the intermediate layer 10 is a T-die method. Since transparency can be improved by suppressing crystallization during sheet molding as much as possible, it is preferable to select a casting temperature and a sheet molding speed as appropriate in consideration of transparency, and the casting temperature is in a temperature range of 0 to 40 ° C. Preferably there is. If the casting temperature is too high, the cooling efficiency at the time of sheet forming is lowered, and transparency may be impaired. After casting and forming a sheet, it is preferable to heat-treat the sheet forming the intermediate layer 10 in order to improve the rigidity.

  The laminated sheet 100 for a packaging body in the present invention is preferably subjected to heat treatment in order to improve rigidity. The heat treatment applied as desired is preferably performed in a temperature range of 60 ° C. or higher and a crystal melting peak temperature (Tm) of the A component or lower. The heat treatment can be performed using a heating roll, heated air, an inert liquid, and the like, and among these, it is preferable that a continuous treatment with a heating roll is performed.

  The heat treatment was performed on the package sheet 100 after the heat treatment, from a thermogram obtained by heating from −40 ° C. to 200 ° C. at a heating rate of 10 ° C./min by a differential scanning calorimeter (DSC). It is preferable to carry out until the amount of heat (ΔHc) is not detected.

<Laminated sheet 100 for packaging>
The tensile elastic modulus obtained in accordance with JIS K 6732 of the laminated sheet 100 for a packaging body of the present invention is preferably 1200 to 4000 MPa, more preferably 1500 to 4000 MPa, and 1800 to 4000 MPa. Further preferred. If this tensile elastic modulus is too small, there may be practical problems such as insufficient rigidity (waist) when used as a package. On the other hand, if this tensile modulus is too large, it may be difficult to produce industrially.

  It is preferable that the total haze value calculated | required based on JISK7105 of the laminated sheet 100 for packaging bodies of this invention is less than 5.0%. A small total haze value indicates a high transparency. If the total haze value is too large, the package formed from the laminated sheet for package 100 of the present invention lacks transparency and aesthetics, and the stored product may not be clearly visible from the outside.

  In order to reduce the total haze value, the growth of resin crystals constituting the intermediate layer 10 is prevented by quenching the intermediate layer 10 or the intermediate layer 10 is formed using a crystal nucleating agent which is a C component. Techniques such as making resin crystals fine or blending petroleum resin as the B component in the intermediate layer 10 can be taken. In order to improve the transparency and make the package more suitable, the total haze value is preferably less than 4.0%, and more preferably less than 3.0%.

  The pencil hardness obtained in accordance with JIS K 5600 of the laminated sheet 100 for a packaging body of the present invention is preferably HB or more, and more preferably F or more. The pencil hardness indicates the surface hardness of the laminated sheet 100 for a packaging body. The higher the pencil hardness, the harder the surface is to be damaged when used as a packaging body. It is preferable because it can be easily visually recognized.

  Although the thickness of the laminated sheet 100 for a package of the present invention is not particularly limited, it is preferably 100 to 1000 μm, and more preferably 200 to 500 μm. If this thickness is too small, there may be practical problems such as lack of rigidity (waist) when used as a package. On the other hand, if the thickness is too large, there may be a problem when the ruled line is processed to form a case, or the transparency may be lowered and the stored item may not be easily visible.

  In the laminated sheet 100 for a packaging body of the present invention, the ratio of the thickness of the intermediate layer 10 to the thickness of the entire laminated sheet 100 for a packaging body is preferably 0.30 to 0.98. Here, if this ratio is too small, it is necessary to use a relatively thick outer layer 10, and it may be difficult to industrially obtain an outer layer having such a thickness. On the other hand, if this ratio is too large, it may not be possible to provide the desired impact resistance and folding ruled line workability desired in the present invention.

  In the intermediate layer 10 and / or the outer layer 20 in the laminated sheet 100 for a packaging body of the present invention, a heat stabilizer, an ultraviolet absorber, a lubricant, a weather stabilizer, a slip agent, an antistatic agent, an antifogging agent, a pigment, Various additives such as dyes usually used in polyolefins may be added within a range not impairing the effects of the present invention.

<Packaging body>
The laminated sheet 100 for a packaging body of the present invention is used as a transparent packaging body (transparent case) excellent in folding ruled line workability and scratch resistance and suitable for storing cosmetics, clothing, foodstuffs, stationery, etc. can do.

  The laminated sheet 100 for a packaging body of the present invention can be punched into a predetermined shape and simultaneously subjected to bending ruled line processing to form a case, thereby forming the packaging body of the present invention. The folded ruled line can be formed by pressing a ruled line blade against the surface located on the inner side when the sheet is folded, as described in, for example, Japanese Patent Laid-Open No. 2003-292023. The folding ruled line is preferably one having a structure that is easy to bend when bent and is not easily damaged when bent. By providing the laminated sheet 100 for packaging of the present invention with a ruled line having a suitable structure, a packaging body having a desired shape formed by bending the laminated sheet 100 for packaging can be obtained.

  Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited thereto.

Example 1
Polypropylene resin (manufactured by Nippon Polypro Co., Ltd., FY6H, Tm: 165 ° C., ΔHm: 96.1 J / g, MFR: 1.9 g / 10 min) (hereinafter referred to as “PP-1”) As a petroleum resin that is a B component, a hydrogenated petroleum resin (Arakawa Chemical Co., Ltd., Alcon P125, softening point: 125 ° C.) is used, and the mass ratio of the A component to the B component is The resin composition in which “component A: component B” = “75:25” was dry blended.

  This dry blended resin composition is melt kneaded at a set temperature of 240 ° C. using a 40 mm co-directional twin screw extruder (L / D = 36) equipped with a T die, and extruded at a casting temperature of 20 ° C. Formed. A biaxially stretched polypropylene film (Toray Industries, Inc., 2500S, 40 μm) (hereinafter abbreviated as “OPP-1”) is used as the outer layer A, and the printed layer is formed. The outer layer A is used as the outer layer B, and the outer layer A is bonded to the intermediate layer from the cast roll side and the nip roll side so that the side on which the printed layer is formed is bonded to the intermediate layer. As a result, a 300 μm laminated sheet for packaging (configuration: outer layer A (OPP-1) / intermediate layer / outer layer B (OPP-1) = 40 μm / 220 μm / 40 μm) was obtained.

(Example 2)
In Example 1, not only the outer layer A but also the outer layer B was used in the same manner as in Example 1 except that a biaxially stretched polypropylene film in which a printing layer was previously formed was used. : Outer layer A (OPP-1) / intermediate layer / outer layer B (OPP-1) = 30 μm / 240 μm / 30 μm).

(Example 3)
In Example 1, a biaxially stretched polypropylene-based film (manufactured by Tosero Co., Ltd., HC-OPS, 30 μm) (hereinafter abbreviated as “OPP-2”) having the printing layer formed in advance as the outer layer A was printed. A 300 μm laminated sheet for packaging (configuration: outer layer A (OPP-2) / intermediate layer / outer layer B (OPP), except that OPP-2 in which no layer is formed was changed to outer layer B. -2) = 30 μm / 240 μm / 30 μm).

Example 4
In Example 1, as a polypropylene resin as component A, a polypropylene resin (EG7F, Tm: 145 ° C., ΔHm: 76.0 J / g, MFR: 1.3 g / 10 min, manufactured by Nippon Polypro Co., Ltd.) (hereinafter, “ PP-2 "is used, and 0.2 parts by mass of C-crystal nucleating agent (manufactured by Nippon Chemical Co., Ltd., Gelol MD-LM30) is added to 100 parts by mass of PP-2. In the same manner as in Example 1, except that the resin composition was used as a resin composition, a 300 μm laminated sheet for packaging (configuration: outer layer A (OPP-1) / intermediate layer / outer layer B (OPP-1) = 40 μm / 220 μm / 40 μm) was obtained.

(Example 5)
In Example 1, a hydrogenated petroleum resin (Arakawa Chemical Co., Ltd., Alcon P140, softening point: 140 ° C.) was used as the petroleum resin as the B component, and the mass ratio between the A component and the B component was “A In addition to adding 0.2 parts by mass of a crystal nucleating agent (manufactured by Shin Nippon Rika Co., Ltd., Gelall MD-LM30) to 100 parts by mass of the resin composition in which “component: B component” = “80:20”. Obtained a 300 μm laminated sheet for packaging (configuration: outer layer A (OPP-1) / intermediate layer / outer layer B (OPP-1) = 40 μm / 220 μm / 40 μm) in the same manner as in Example 1.

(Comparative Example 1)
In Example 1, an intermediate layer is formed in the same manner as in Example 1 with the mass ratio of the A component and the B component being “A component: B component” = “70:30”, and this intermediate layer is an outer layer. A single-layer sheet (configuration: intermediate layer = 300 μm) consisting of only a 300 μm intermediate layer was obtained in the same manner as in Example 1 except that the axially stretched polypropylene film was not laminated.

(Comparative Example 2)
In Example 1, a 300 μm laminated sheet for packaging (configuration) except that the mass ratio of the A component and the B component was changed to “A component: B component” = “50:50”. : Outer layer A (OPP-1) / intermediate layer / outer layer B (OPP-1) = 40 μm / 220 μm / 40 μm).

(Comparative Example 3)
In Example 1, only the 300 μm intermediate layer was used in the same manner as in Example 1, except that the petroleum resin as the component B was not blended and the both sides of the intermediate layer were not laminated with the biaxially stretched polypropylene film as the outer layer. A single layer sheet (configuration: intermediate layer = 300 μm) was obtained. The printing layer was provided in the inner surface side (inner surface side at the time of forming in a case shape) of the obtained single layer sheet.

(Comparative Example 4)
In Example 4, a single layer sheet (configuration: intermediate layer = 300 μm) consisting of only a 300 μm intermediate layer was obtained in the same manner as in Example 4 except that the outer layer was not laminated with a biaxially stretched polypropylene film. The printing layer was provided in the inner surface side (inner surface side at the time of forming in a case shape) of the obtained single layer sheet.

  About the sheet | seat obtained by said Example and comparative example, it evaluated by the following evaluation methods. The evaluation results are shown in Table 1.

<Evaluation method>
(Crystal melting peak temperature (Tm), crystal melting heat (ΔHm))
For the crystal melting peak temperature (Tm) and the crystal melting calorie (ΔHm), a differential scanning calorimeter “DSC-7” manufactured by PerkinElmer Co., Ltd. was used, and 10 mg of a sample was heated at a heating rate of 10 ° C. according to JIS K 7121 and JIS K 7122. The temperature was raised from −40 ° C. to 200 ° C./min, held at 200 ° C. for 1 minute, then cooled to −40 ° C. at a cooling rate of 10 ° C./min, held for 1 minute, and then heated at 10 ° C./min. It calculated | required from the thermogram when it heated up again by min.

(Rule line workability)
Using the ruled line blade described in Japanese Patent Application Laid-Open No. 2003-292020, 10 sheets were subjected to folding ruled line processing (in the laminated sheet, folding ruled line processing was applied to the outer layer A side), and cracks during the ruled line processing were performed. The presence or absence of this was visually checked, and the case where no cracks occurred was evaluated as “◯”, and the case where even one crack occurred was evaluated as “x”.
In addition, the following evaluation was implemented about the thing in which no crack generate | occur | produced.

(Tensile modulus)
In accordance with JIS K 6732, the tensile elastic modulus was determined under conditions of a temperature of 23 ° C. and a test speed of 5 mm / min. The flow direction from the extruder in the obtained sheet was measured as the longitudinal direction, and the direction perpendicular to the longitudinal direction was measured as the transverse direction. The results of evaluation based on the following criteria are also shown.
(◎): Tensile modulus is 1500 MPa or more (O): Tensile modulus is 1200 MPa or more and less than 1500 MPa (x): Tensile modulus is less than 1200 MPa

(Total haze value)
Based on JIS K 7105, the total haze value (%) of the obtained sheet was determined. The total haze value indicates that the smaller the value, the higher the transparency. The results of evaluation based on the following criteria are also shown.
(◎): Total haze is less than 3.0% (◯): Total haze is 3.0% or more and less than 5.0% (x): Total haze is 5.0% or more

(Pencil hardness)
In accordance with JIS K 5600, the pencil hardness of the obtained sheet was measured (in the laminated sheet, the pencil hardness of the surface on the outer layer A side was measured). The results of evaluation based on the following criteria are also shown.
(◎): Pencil hardness is F or more (○): Pencil hardness is HB
(×): Pencil hardness is B or less

(Abrasion resistance of printing)
The obtained sheet was rubbed 10 times with # 2000 sandpaper, and then the degree of scratching on the printed surface was observed. In addition, in the lamination sheet, the surface by the side of the outer layer B was rubbed with sandpaper, and about the single layer sheet which does not laminate | stack a biaxially stretched polypropylene film, the printing surface side was rubbed and evaluated.
(○): Not scratched (×): Scratched

(Aesthetics)
The obtained sheet | seat was formed in case shape and the aesthetics were confirmed visually. In addition, in the lamination sheet, the outer layer A side was made into the outer side, and it shape | molded in the case shape.
(○): Clear feeling and excellent aesthetics (×): Inferior clear feeling and poor aesthetics

(Evaluation results)
Table 1 shows the following. In Examples 1, 2, 3, 4, and 5, by laminating a biaxially stretched polypropylene film as both outer layers, it is possible to improve the ruled line workability, improve the rigidity, and ensure transparency. Moreover, the laminated sheet for packaging bodies which can be used as the packaging body which has high pencil hardness, excellent scratch resistance, excellent printing abrasion resistance, and excellent aesthetics could be produced.

  The laminated sheets for packaging bodies obtained in Comparative Examples 1 and 2 were inferior in ruled line workability. The sheet obtained in Comparative Example 3 had low pencil hardness and inferior scratch resistance, and inferior printing abrasion resistance. Moreover, since transparency was inferior, the aesthetics of the obtained package were inferior. In addition, the sheet obtained in Comparative Example 4 was inferior in rigidity, inferior in pencil hardness, inferior in scratch resistance, and inferior in printing abrasion resistance.

  While the present invention has been described in connection with embodiments that are presently the most practical and preferred, the present invention is not limited to the embodiments disclosed herein. However, it can be appropriately changed without departing from the gist or the idea of the invention that can be read from the claims and the entire specification, and is formed from the laminated sheet for a packaging body and such a laminated sheet for the packaging body with such a modification. Packaging must also be understood as being within the scope of the present invention.

It is explanatory drawing which shows one Embodiment of the laminated constitution of the laminated sheet for package bodies of this invention.

Explanation of symbols

100 Laminated sheet for packaging 10 Intermediate layer 20A, 20B Outer layer 30 Print layer

Claims (5)

A laminated sheet having an intermediate layer and an outer layer laminated on both sides thereof,
The intermediate layer is a polypropylene film mainly composed of the following component A,
The outer layer is a biaxially stretched polypropylene film,
A laminated sheet for a packaging body having a printed layer on a side laminated with an intermediate layer in at least one of the outer layers.
Component A: Polypropylene resin having a crystal melting heat (ΔHm) of 70 to 120 J / g determined from a thermogram obtained by a differential scanning calorimeter (DSC) at a heating rate of 10 ° C./min. The intermediate layer further has the following B component, and the mass ratio of the A component and the following B component is "95: 5" to "60:40" (A component: B component). A laminated sheet for packaging as described in 1.
Component B: at least one resin selected from the group consisting of petroleum resins, terpene resins, coumarone-indene resins, rosin resins, and hydrogenated derivatives thereof.   The said intermediate | middle layer has a crystal nucleating agent as C component further, and the compounding quantity is 0.05-1.00 mass part with respect to 100 mass parts of said A component. Laminated sheet for packaging.   The laminated sheet for packaging bodies according to any one of claims 1 to 3, wherein a ratio of the thickness of the intermediate layer to the thickness of the entire laminated sheet for packaging bodies is 0.30 to 0.98. The package formed with the laminated sheet for package bodies in any one of Claims 1-4.

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