JP5948912B2 - Easily tearable embossed film and packaging material using the same - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a packaging material such as a tape piece, a label, a lid, etc., based on a resin film, and more specifically, a frozen / refrigerated food, a pharmaceutical, a building material label using a cyclic polyolefin, and these. Can be used as tapes, lids, outdoor advertising stickers, industrial product names (labels with instructions for use), etc. The present invention relates to an easily tearable embossed film and a packaging material using the same.

  Conventionally, as outdoor advertising stickers, frozen foods, refrigerated foods, pharmaceutical packaging materials, labels and tapes attached to containers, etc., the thermoplastic resin has better water resistance than paper substrates. Films made of these, in particular polyolefin films, have been used. However, such plastic film is tougher and easier to stretch than paper, so it is inferior in cutting properties. When taking out articles that have been collected with tape or labels, it is difficult to take out and cut by hand. It is.

  Various forms are provided as a device for improving cutability and dividing and taking out one by one from an accumulation of individual packages (see, for example, Patent Documents 1 to 3). In Patent Documents 1 and 2, a part to be attached to an article is provided in a part of the film, and a perforation or the like for expressing hand cutting properties is provided in the other part, thereby dividing the individual package and label (tape). ). In order to make such a sticking part a part, it is necessary to design the product in accordance with the final form from the time of manufacture of the label. A machine having a cutting / peeling introduction function by secondary processing such as V-cut and I-cut is required, and the complexity of the manufacturing process is inevitable.

  In the technique provided in Patent Document 3, the adhesive is applied to the entire film by using a pressure-sensitive adhesive. However, the perforation for separating the articles individually is also used. It is necessary to provide a separating means. If this perforation is pasted on the article, its function will not be manifested, so it will not be possible to develop the article in a different shape or size, and a label corresponding to the intended article. It is necessary to design each time and lacks versatility.

  Depending on the food, the whole container may be reheated when cooking or eating, but such heated packaging is difficult to enter due to its hotness, or it becomes slippery due to the wet surface. For this reason, there is a problem that even if a perforation is applied, it cannot be opened well.

  Furthermore, in recent years, universal designs have also been required for various packaging materials, and it is easier for persons with visual disabilities and elderly people to identify, interpret and understand the packaging opening method and contents display. It has become necessary to be designed. For this reason, films for packaging materials that have been smooth in the past have often been embossed with Braille characters, symbols that indicate unsealed parts, and pictures that indicate the contents (for example, patents). Reference 4). In addition, it is also devised to be barrier-free by attaching braille labels to handrails, door openings, elevator floor display, and the like.

  However, general-purpose plastic materials such as PET (polyethylene terephthalate) used in Patent Document 4 have a repulsive force (Young's modulus) to return to the original shape, so that irregularities are simply formed on the surface. However, durability is often insufficient. For this reason, in order to form surface irregularities, the ink to be printed is given foaming properties (see, for example, Patent Document 5), or other materials are embedded on the back side after the irregularities are formed to increase the durability of the irregularities. Although some ideas have been proposed (for example, see Patent Document 6), all of them lack generality due to the use of special materials and the complexity of work processes, and still leave the area as high-grade / special packaging materials. The current situation is that it is not possible.

Japanese Patent Laid-Open No. 11-349039 JP 2001-348055 A Japanese Patent Laid-Open No. 11-245966 JP 2002-162896 A JP 2006-076210 A JP 2006-053247 A

  An object of the present invention is made in view of the above-described problems, and is excellent in easy tearing, and provided with unevenness on the surface, so that it has an anti-slip effect and a person who has difficulty in vision. It is to provide an easily tearable embossed film having good versatility and durability, and a packaging material such as a label, a tape, and a lid material, which can provide information by touch to a person.

  As a result of diligent research to solve the above-mentioned problems, the present inventor applied an adhesive or heat-sealed to a substrate having a resin layer containing a cyclic polyolefin resin and a resin layer containing a polyolefin resin. The laminated film obtained by laminating the layers can be unevenly formed by embossing efficiently on the opposite surface of the adhesive layer and the heat seal layer, and the unevenness is not deformed even by friction or aging, It has been found that it has excellent durability without any special efforts, and the present invention has been completed.

  That is, the present invention includes a resin layer (A) containing a cyclic polyolefin resin (a), a resin layer (B) containing a polyolefin resin (b), an adhesive layer (C1) or a heat seal layer (C2 ), And the thickness of the substrate portion excluding the adhesive layer (C1) or the heat seal layer (C2) of the laminate film is 100 μm or less, and the adhesive layer (C1) or the heat seal layer ( An easily tearable embossed film characterized in that the opposite surface of C2) is uneven by embossing, and a packaging material using the same.

  The laminated film produced in the present invention is a film having good hand cutting properties that can be easily cut and separated by hand without performing special processing such as perforation and V-cut. Furthermore, since the laminated film has almost no change in physical properties due to humidity, curling can be suppressed, and the shape stability and dimensional stability of the unevenness imparted to the surface by embossing are excellent, and blocking is hardly generated. From these things, it is excellent in laminating, printing, and packaging machine suitability, and can suppress the wavy of the film due to absorption of humidity. In addition, it has moderate rigidity and is suitable for labeling, tape, name, etc. that are directly attached to pharmaceuticals, foods, industrial materials, building materials, etc., or packaging materials when packaging these alone or in combination. can do.

  The easily tearable embossed film of the present invention comprises a resin layer (A) containing at least a cyclic polyolefin resin (a), a resin layer (B) containing a polyolefin resin (b), and an adhesive layer (C1) or A laminated film having a heat seal layer (C2). In the present application, “containing” means that the specific resin is contained at 10% by mass or more with respect to the total mass of the resin composition used for forming the resin layer, preferably The content is 40% by mass or more, particularly preferably 70% by mass or more.

  Examples of the cyclic polyolefin resin (a) contained in the resin layer (A) in the present invention include a norbornene polymer, a vinyl alicyclic hydrocarbon polymer, and a cyclic conjugated diene polymer. Among these, norbornene-based polymers are preferable. The norbornene-based polymer includes a ring-opening polymer of a norbornene-based monomer (hereinafter referred to as “COP”), a norbornene-based copolymer obtained by copolymerizing a norbornene-based monomer and an olefin such as ethylene (hereinafter, referred to as “COP”). , “COC”). Furthermore, COP and COC hydrogenates are particularly preferred. Further, the weight average molecular weight of the cyclic polyolefin resin (a) is preferably 5,000 to 500,000, more preferably 7,000 to 300,000.

  The norbornene monomer used as a raw material for the norbornene polymer is an alicyclic monomer having a norbornene ring. Examples of such norbornene-based monomers include norbornene, tetracyclododecene, ethylidene norbornene, vinyl norbornene, ethylidetetracyclododecene, dicyclopentadiene, dimethanotetrahydrofluorene, phenyl norbornene, methoxycarbonyl norbornene, methoxy And carbonyltetracyclododecene. These norbornene monomers may be used alone or in combination of two or more.

  The norbornene-based copolymer is a copolymer of the norbornene-based monomer and an olefin copolymerizable with the norbornene-based monomer, and examples of such olefin include the number of carbon atoms such as ethylene, propylene, and 1-butene. Examples thereof include olefins having 2 to 20; cycloolefins such as cyclobutene, cyclopentene, and cyclohexene; and non-conjugated dienes such as 1,4-hexadiene. These olefins can be used alone or in combination of two or more.

  Moreover, it is preferable that the glass transition point (Tg) of the said cyclic polyolefin resin (a) is 70 degreeC or more from the point of the heat resistance of the easily tearable embossed film obtained, and high rigidity, The polyolefin resin (after-mentioned) In the case of multilayering with the resin layer (B) containing b), Tg is 200 ° C. or less from the viewpoint of possible production by a coextrusion lamination method and industrial raw material availability. Is preferred. The temperature is particularly desirably 80 ° C to 180 ° C. As the cyclic polyolefin resin (a) having such Tg, the content ratio of the norbornene monomer is preferably in the range of 20 to 90% by weight, more preferably 25 to 90% by weight, still more preferably. 30 to 85% by weight. When the content ratio is within this range, the heat resistance, rigidity, hand cutting property, moisture resistance, and processing stability (uneven shape stability) of the resulting embossed film are improved. In addition, the glass transition point (Tg) in this invention is a value obtained by measuring by DSC.

  On the other hand, norbornene copolymers with a high glass transition point (Tg) have low tensile strength, are too rigid, and are extremely susceptible to tearing and tearing. In consideration of suitability, it is also possible to blend a high Tg product and a low Tg product having a glass transition point of less than 100 ° C.

  As a commercial product that can be used as the cyclic polyolefin resin (a), examples of the ring-opening polymer (COP) of the norbornene monomer include “ZEONOR” manufactured by Nippon Zeon Co., Ltd., and norbornene. Examples of the system copolymer (COC) include “Appel” manufactured by Mitsui Chemicals, Inc., “TOPAS” manufactured by Polyplastics Co., Ltd., and the like.

  In addition, depending on the type of cyclic polyolefin resin (a) used, the rigidity is too high as described above, which may cause problems such as dropping or vibration during transportation, and tearing or cutting easily during pasting. is there. In such a case, a polyolefin resin not containing a cyclic structure, particularly a polyethylene resin or a polypropylene resin, which is compatible with the cyclic polyolefin resin (a) and does not impair the effects of the present invention. It is preferable that the resin layer (A) is used alone or in combination of two or more.

  The resin layer (B) in the present invention is a resin layer containing a polyolefin resin (b). Even if the resin layer (A) alone is a case where the resin layer (A) contains a polyolefin-based resin, the tearability when formed into a film is increased, resulting in insufficient processing suitability. A resin layer containing the polyolefin-based resin (b) is laminated from the viewpoint that the tearability by hand can be maintained while compensating for this point.

  As the polyolefin-based resin (b), a polyethylene-based resin or a polypropylene-based resin is used from the viewpoint of excellent interlayer adhesion when laminated with the above-described resin layer (A) and industrial availability. preferable.

  In the resin layer (A), a polyethylene resin preferable as a polyolefin resin (b) for forming the resin layer (B), which is preferable when used in combination with the cyclic polyolefin resin (a). Since the polypropylene resin is the same, it will be described without distinguishing both.

As the polyethylene resin, it is preferable to use a polyethylene resin having a density of 0.880 g / cm ² or more and less than 0.965 g / cm ² from the viewpoint of processing stability and easy tearability.

  Examples of the polyethylene resin include very low density polyethylene (VLDPE), linear very low density polyethylene (VLLDPE), linear low density polyethylene (LLDPE), low density polyethylene (LDPE), medium density polyethylene (MDPE), and high density. Polyethylene resins such as polyethylene (HDPE), ethylene-vinyl acetate copolymer (EVA), ethylene-methyl methacrylate copolymer (EMMA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methyl acrylate (EMA) ) Copolymers, ethylene copolymers such as ethylene-ethyl acrylate-maleic anhydride copolymer (E-EA-MAH), ethylene-acrylic acid copolymer (EAA), ethylene-methacrylic acid copolymer (EMAA), etc. Polymer; further ethylene-acrylic acid copolymer Body ionomers, ethylene - mentioned ionomer methacrylic acid copolymer, and, alone, may be used by mixing two or more kinds. Among these, VLDPE, VLLDPE, LDPE, and LLDPE are preferable from the viewpoints of easy tearability, workability (film formability, embossability), and maintaining the shape of the surface irregularity imparted by embossing.

  The LDPE may be a branched low density polyethylene obtained by a high pressure radical polymerization method, and is preferably a branched low density polyethylene obtained by homopolymerizing ethylene by a high pressure radical polymerization method.

  As VLLDPE and LLDPE, an ethylene monomer as a main component and a comonomer such as butene-1, hexene-1, octene-1, and 4-methylpentene by a low-pressure radical polymerization method using a single site catalyst. -Copolymerized olefin. As a comonomer content rate, it is preferable that it is the range of 0.5-20 mol%, and it is more preferable that it is the range of 1-18 mol%.

  Examples of the single-site catalyst include various single-site catalysts such as metallocene catalyst systems such as combinations of metallocene compounds of Group IV or V transition metals and organoaluminum compounds and / or ionic compounds. In addition, the single-site catalyst has a uniform active site, so the molecular weight distribution of the resulting resin is sharper than a multi-site catalyst with a non-uniform active site. The storage stability (physical property stability) is improved.

Density of the polyethylene resin as mentioned above is preferably less than 0.880 g / cm ² or more 0.965 g / cm ^2. If the density is within this range, it has appropriate rigidity, excellent mechanical strength such as pinhole resistance, and film film formability and extrusion suitability are improved. Moreover, it is preferable that melting | fusing point is generally the range of 60-130 degreeC, and 70-120 degreeC is more preferable. If melting | fusing point is this range, processing stability and coextrusion workability with cyclic polyolefin resin will improve. Moreover, it is preferable that it is 2-20 g / 10min, and, as for MFR (190 degreeC, 21.18N) of the said polyethylene-type resin, it is more preferable that it is 3-10 g / 10min. When the MFR is within this range, the extrusion moldability is improved.

  Since such a polyethylene resin has good compatibility with the cyclic polyolefin resin (a), it is possible to maintain transparency when laminated or mixed. Further, it can be laminated with the resin layer (A) without using an adhesive resin or the like, and since it has flexibility, the pinhole resistance is also improved. Furthermore, when improving pinhole resistance, it is preferable to use VLDPE or LLDPE.

  Examples of the polypropylene resin include propylene homopolymer, propylene / α-olefin random copolymer, such as propylene-ethylene copolymer, propylene-butene-1 copolymer, propylene-ethylene-butene-1 copolymer. Examples include coalesced metallocene catalyst polypropylene. These may be used alone or in combination. A propylene-α-olefin random copolymer is desirable, and a propylene / α-olefin random copolymer polymerized using a metallocene catalyst is particularly preferable. When these propylene-based resins are used, the heat resistance of the resulting film can be improved and the softening temperature can be increased. Therefore, after sticking as a label, boil at 100 ° C. or lower, or hot filling, or It can also be suitably used when steam / high pressure heat sterilization such as retort sterilization at 100 ° C. or higher.

  These polypropylene resins preferably have an MFR (230 ° C.) of 0.5 to 30.0 g / 10 min and a melting point of 110 to 165 ° C., more preferably an MFR (230 ° C.) of 2 0.0-15.0 g / 10 min, melting point is 115-162 ° C. If MFR and melting | fusing point are this range, the dimensional stability of the film obtained will be favorable and the film-forming property at the time of setting it as a film will also improve.

  The easily tearable embossed film of the present invention is based on a film in which the resin layer (A) and the resin layer (B) are laminated, and is preferably used as a packaging material for labels, tapes, lids, etc. It is essential to provide an adhesive layer (C1) or a heat seal layer (C2) on one side of the substrate.

  When the adhesive layer (C1) and the heat seal layer (C2) are provided, since the resin layer (A) has a high degree of maintaining power when the surface treatment such as corona treatment is performed, the resin layer (A ) Side is preferably provided with an adhesive layer (C1) and a heat seal layer (C2). Therefore, the resin layer (B) / the resin layer (A) / the adhesive layer (C1) or the heat seal layer (C2) It is preferable to laminate in order.

  Further, from the viewpoint of further preventing deterioration due to embossing on the surface due to aging, friction, etc., it is preferable to apply the embossing to the resin layer (A), and in particular, the (A) surface is convex. Thus, it is more preferable to emboss and laminate in the order of the resin layer (A) / the resin layer (B) / the resin layer (A) / the adhesive layer (C1) or the heat seal layer (C2). At this time, the cyclic polyolefin resin (a) used for the outermost resin layer (A), the adhesive layer (C1), and the cyclic polyolefin resin (A) used for the inner resin layer (A) on which the heat seal layer (C2) is laminated ( With a), the same composition may be used, or different ones may be used. By adopting such a multilayer structure, printability on the surface is improved and curling of the film itself can be further prevented.

  In order to form the pressure-sensitive adhesive layer (C1), various pressure-sensitive adhesives can be used, but it is preferably formed using a pressure-sensitive pressure-sensitive adhesive. Examples of the pressure-sensitive adhesive include, for example, a polyisobutylene rubber, a butyl rubber, a rubber adhesive in which a mixture thereof is dissolved in an organic solvent such as benzene, toluene, xylene, hexane, or a bisethylene acid rosin in the rubber adhesive. A blend of tackifiers such as ester, terpene / phenol copolymer, terpene / indene copolymer, or 2-ethylhexyl acrylate / n-butyl acrylate copolymer, 2-ethylhexyl acrylate / ethyl acrylate / Examples thereof include an acrylic pressure-sensitive adhesive prepared by dissolving an acrylic copolymer having a glass transition point of −20 ° C. or less such as a methyl methacrylate copolymer in an organic solvent.

Moreover, it is preferable to apply an anchor coating agent before applying the pressure-sensitive adhesive. As the anchor coating agent, polyurethane, polyisocyanate / polyether polyol, polyisocyanate / polyethyleneimine, alkyl titanate, etc. can be used, and these are generally dissolved in organic solvents such as methanol, water, ethyl acetate, toluene, hexane and the like. Used. The coating amount of the anchor coating agent, 0.01-5 g / ^{m 2} by solid content after coating and drying is preferably 0.05 to 2 g / ^{m 2.}

Moreover, when laminating | stacking a heat seal layer (C2), it is possible to manufacture by the coextrusion laminating method using the same polyolefin-type resin as the said resin layer (B), and the resin layer (A) This is preferable from the viewpoint of good interlayer adhesion. Furthermore, it is preferable to use a polyolefin-based resin having a melting point lower than that of the resin used for the surface resin layer from the viewpoint of preventing the surface layer from being “resined” on the seal bar. For example, 0.88 to 0.93 g It is preferable to use a low density, medium density polyethylene resin or the like of less than / cm ³ . The heat seal layer (C2) may be composed of a single layer or may be composed of multiple layers. By forming a multilayer structure, for example, the easily tearable embossed film of the present invention is used as a container lid. When used, it becomes possible to impart easy-openability.

  In the case where the easy-opening property is imparted by cohesive failure of the heat seal layer (C2), for example, it can be easily imparted by using a mixture of a polyethylene resin and a polypropylene resin. In addition, when an acid-modified polyethylene resin is used, when it is used as a lid for a plastic, particularly PET container, it can be peeled between the container and the container. Furthermore, for example, a heat seal layer is formed by laminating a layer mainly composed of an ethylene / α-olefin random copolymer and a resin layer mainly composed of a polypropylene-based resin, thereby forming a heat seal layer. Peeling between layers can be made possible.

  In the easily tearable embossed film of the present invention, it is essential that the thickness of the substrate part excluding the above-mentioned adhesive layer (C1) or heat seal layer (C2) is 100 μm or less. When the thickness of the substrate exceeds 100 μm, the thickness of the resulting embossed film increases, resulting in insufficient shape following to the adherend when used as a label, tape, etc., during long-term storage and transportation It may cause peeling of the surface, or unevenness due to embossing may become unclear, and the effects of the present invention may not be achieved. More preferably, the thickness of the substrate portion is in the range of 20 to 80 μm.

  In the easily tearable embossed label of the present invention, since the resin layer (A) is excellent in tearability, the resin layer (B), the adhesive layer (C1), and the heat seal layer (C2) may be laminated by hand. Although it is possible to maintain the tearability, it is also possible to use a paper base material that originally has tearability to form a laminate. From the viewpoint of surface gloss of the resulting film, a combination of a paper base material between the resin layer (A) and the adhesive layer (C1), that is, resin layer (A) / paper base material / adhesive layer (C1 It is preferable to have a laminated portion.

  As the paper base material that can be used at this time, any kind of paper substrate may be used as long as the effects of the present invention are not impaired. For example, cast coated paper, art paper, coated paper, high quality paper and the like can be mentioned. Also, vapor-deposited paper, synthetic paper, cloth, non-woven fabric, metal foil and the like can be used. These may be used in a single layer or may be laminated. Of these, high-quality paper is preferable.

  The method for adhering the resin layer (A) and the paper substrate is not particularly limited, and examples thereof include dry lamination, wet lamination, non-solvent lamination, and the like that are performed by applying an adhesive. . Moreover, it is also possible to form various layers of the resin layer (A) / paper substrate by applying various laminating methods such as thermal lamination and extrusion lamination which are bonded by thermocompression bonding of a heating roll.

  Examples of the adhesive used in the dry lamination include a polyether-polyurethane adhesive and a polyester-polyurethane adhesive.

  In the case where the adhesive layer (C1) is laminated directly on the resin layer (A) or the resin layer (B) or on the paper substrate, the method of laminating the paper layer on the paper substrate is particularly limited. For example, a method using a coating machine such as an air knife coater, blade coater, roll coater, gravure coater, comma coater or gate roll coater is simple. A similar coating machine can also be used when using the anchor coating agent described above.

  The method of volatilizing the anchor coating agent and the medium contained in the adhesive after coating the anchor coating agent and the adhesive used in combination is not particularly limited. A method of drying using is generally used. The drying temperature may be a temperature that can volatilize the medium and does not adversely affect the substrate.

Although the coating amount at the time of apply | coating an adhesive is not specifically limited, As an application amount of an adhesive, it is 3-40 g / m < ² > by solid content amount, Preferably it is 10-30 g / m < ² >. The thickness of the pressure-sensitive adhesive layer (C1) after coating and drying is generally 10 to 50 μm in the case of an acrylic pressure-sensitive adhesive and 80 to 150 μm in the case of a rubber-based pressure-sensitive adhesive. When the pressure-sensitive adhesive layer (C1) is thin, the initial pressure-sensitive adhesive strength is low, and when the pressure-sensitive adhesive layer (C1) is thick, the initial pressure-sensitive adhesive force tends to be high. It is preferable to select and determine appropriately depending on the method of use and the like.

In order to preserve the embossed film of the present invention, it is preferable to laminate a release paper for protecting the adhesiveness of the adhesive layer (C1) on the adhesive layer (C1). The release paper is not particularly limited, and examples thereof include high-grade base paper such as glassine paper, clay-coated paper, kraft paper, and high-quality paper, such as casein, dextrin, starch, carboxymethylcellulose, methylcellulose, and ethylcellulose. , Hydroxyethyl cellulose, polyvinyl alcohol, styrene-butadiene copolymer, ethylene-vinyl chloride copolymer, methyl methacrylate-butadiene copolymer, ethylene-vinyl acetate copolymer, (meth) acrylic acid ester copolymer natural or Synthetic resin alone or base material provided with a sealing layer used in combination with inorganic pigments such as kaolin, clay, calcium carbonate, calcined clay (calcined kaolin), titanium oxide, silica or organic pigments such as plastic pigment, kraft paper or Polyethylene on fine paper After applying a solvent-type or solvent-free type silicone resin or fluorine resin, etc. to a laminated paper laminated with a synthetic resin, etc., etc., where a release agent layer is formed by heat curing, electron beam or ultraviolet curing, etc. Can be used. The apparatus for applying the release agent is not particularly limited. For example, a bar coater, a direct gravure coater, an offset gravure coater, a flexo coater, an air knife coater, a multi-stage roll coater, etc. are appropriately used. . The coating amount of the release agent layer, 0.5 to 10 g / ^{m 2} by solid content after coating and drying, preferably 1-8 g / ^{m 2.}

  Further, without using a release paper, by providing a release layer that prevents sticking to the adhesive layer (C1) on the surface opposite to the adhesive layer (C1) of the multilayer film obtained above, It is also possible to store in a roll.

  As a method for providing such a release layer, a solvent-type or solvent-free type silicone resin or fluororesin is applied to the surface opposite to the adhesive layer (C1), and then formed by heat curing, electron beam or ultraviolet curing, etc. can do.

The thickness of the release layer is not particularly limited, but the coating amount is 0.5 to 10 g / m ² in terms of the solid content after coating and drying, and the thickness of the layer after drying is 0.5 μm. It is preferable that it is in the range of ˜20 μm from the viewpoint that the balance between the peelability when rewinding from a roll shape and the adhesiveness as a film becomes good.

  The surface of the easily tearable embossed film of the present invention is excellent in surface gloss by being composed of a cyclic polyolefin resin or a resin layer containing a polyolefin resin as a main component as described above. Can do. In particular, when a paper substrate is not used in combination, the transparency is excellent and the visibility of the contents can be improved. In particular, in order to ensure the gloss of the surface reliably, it is preferable that the surface of the film [the surface opposite to the adhesive layer (C1) or the heat seal layer (C2)] be a layer containing a cyclic polyolefin resin.

  In particular, as the surface glossiness, for example, in the evaluation based on JIS P8138-1976, it is easy to set the value to 90% or more. For example, the resin layer (A) mainly composed of the cyclic polyolefin is formed on the surface. If it is provided and release paper is used to protect the adhesive layer (C1), it may be 100% or more.

  For each of the resin layers (A), (B), (C1), (C2), an antifogging agent, an antistatic agent, a thermal stabilizer, a nucleating agent, an antioxidant, a lubricant, Components such as an anti-blocking agent, a release agent, an ultraviolet absorber, and a colorant can be added within a range that does not impair the object of the present invention. In particular, it is possible to make the content opaque or white due to the concealability of the contents and the print appearance characteristics. Furthermore, in order to impart suitability to film forming and suitability for an automatic sticking machine, the friction coefficient of the outermost resin layer is preferably 1.5 or less, more preferably 1.0 or less. It is preferable to appropriately add a lubricant, an antiblocking agent, or an antistatic agent to the corresponding resin layer.

  In the film of the present invention, the surface of the outermost resin layer is treated so that the surface tension of the outermost surface is 38 mN / m or more, preferably 40 mN / m or more. Examples of such treatment methods include corona treatment, plasma treatment, chromic acid treatment, flame treatment, hot air treatment, surface oxidation treatment such as ozone / ultraviolet treatment, and surface unevenness treatment such as sandblasting. Corona treatment is preferable. By performing such a surface treatment, when the film is subjected to a post-process such as printing or aluminum deposition, the coating property of the ink or adhesive is improved, and the adhesion with the ink, aluminum, or adhesive is improved. It is easy to avoid problems such as ink and vapor deposition aluminum dropping off and delamination. In addition, an anchor coating agent or an easy-adhesion coating agent can be applied to further improve adhesion such as vapor deposition and ink.

  Although it does not specifically limit as a manufacturing method of the film of this invention, For example, when providing the base material part except a adhesion layer (C1), and a heat seal layer (C2), each resin layer which comprises all the laminated | multilayer films. The resin or resin mixture used in the above is heated and melted in separate extruders and laminated in the desired multilayer structure in a molten state by a method such as a coextrusion multi-layer die method or a feed block method, followed by inflation or T-die chill roll Examples thereof include a coextrusion method in which a film is formed by a method or the like. This coextrusion method is preferable because the thickness ratio of each layer can be adjusted relatively freely, and a multilayer film excellent in hygiene and cost performance can be obtained. In addition, when a cyclic polyolefin resin (a) used in the present invention and a polyethylene resin are used as the resin layer (B), the difference between the melting point and Tg may increase between the two. The film appearance may deteriorate during processing, or formation of a uniform layer structure may be difficult. In order to suppress such deterioration, a T-die / chill roll method that can perform melt extrusion at a relatively high temperature is preferable.

  Since the film of the present invention is obtained as a substantially unstretched multilayer film by the above production method, it is easy to emboss on the surface, and deep drawing by vacuum forming after pasting as a label or the like. Secondary molding is also possible.

  The embossing forming method on the surface of the laminated film obtained above is not particularly limited, and when the laminated film is formed by T-die extrusion or the like, a metal having a surface uneven pattern on the cooling roll. Various methods including a molding method using a roll (embossing roll) and combinations thereof can be adopted. For example, a roller with diamond particles, mechanical unevenness processing using a cutting blade, laser, electron beam irradiation, plasma irradiation, high pressure discharge punching method, etc. can be adopted, film and packaging material, wall thickness, passing speed, punch diameter It can be appropriately selected depending on the situation.

  Also, when slitting and punching films etc., braille and anti-slip unevenness projecting outward using an embossing device consisting of a male mold with a cylindrical projection and a female mold with a cylindrical hole It is also possible to form

  In addition, by engraving braille, concavo-convex characters, symbols, marks, etc. on the heat-sealing roller or heat-sealing board of the packaging machine, when packaging the contents, the heat-sealing part is placed at the same time as the heat-sealing. Information such as opening position of package, contents, cooking method, and handling method is also formed. The range of the height of the convex shape and the depth of the concave portion that can be reliably recognized by the finger depends on the type of character, symbol, mark, and anti-slip effect, but is usually in the range of 100 to 500 μm.

  The application range of the easily tearable embossed label of the present invention is not particularly limited, and examples thereof include tapes and labels used for foods, pharmaceuticals, industrial parts, building materials, sundries, magazines and the like. In particular, a packaging body that can be easily opened by tearing by hand, can be divided and has a good hand cutting property, and can be suitably used as a tape or a namer used for collecting and integrating individually packaged packaging bodies. . In addition, the temperature, humidity during freezing and refrigeration storage, humidity, condensation due to condensation, little change in physical properties due to shrinkage and elongation, curling can be suppressed, dimensional stability is excellent, and blocking is not likely to occur. In addition, since it is excellent in suitability for printing, packaging, and packaging machinery, it can be suitably used for packaging bodies containing foods and pharmaceuticals.

  In general, embossed shape (concave / convex) retainability is superior for paper and metal, but plastic, which is a polymer material, has a self-healing property, resilience, and a return effect. However, it is known that there will be no sense of resistance over time and it will be difficult to read as Braille. However, the cyclic polyolefin-based resin used in the present invention has a characteristic that it is excellent in bending and processing suitability like metal, and the embossed shape retention performance is far superior among plastic materials. For this reason, after forming the surface unevenness, it can be used as various packaging materials as it is without special post-treatment, and the uneven shape is maintained even if it is not used immediately after embossing. Therefore, it is excellent in versatility and can be provided as daily necessities.

  Next, the present invention will be described in more detail with reference to examples and comparative examples.

Example 1
As a resin for the resin layer (A), a ring-opening polymer of a norbornene monomer [“Apel APL6015T” manufactured by Mitsui Chemicals, MFR: 10 g / 10 min (260 ° C., 21.18 N), glass transition temperature: 145 ° C .; Hereinafter, it is referred to as “COC (1)”. ] Was used. As resin for resin layer (B), linear medium density polyethylene [density: 0.930 g / cm ³ , melting point 125 ° C., MFR: 5 g / 10 min (190 ° C., 21.18 N); hereinafter referred to as “LMDPE” . ] Was used. These resins are respectively supplied to an extruder for a resin layer (A) (caliber 40 mm) and an extruder for a resin layer (B) (caliber 50 mm) and melted at 200 to 230 ° C., and the melted resin is fed into a block. Co-extrusion multilayer film production apparatus (feed block and T-die temperature: 250 ° C.) of T-die / chill roll method each having co-extrusion is performed, and the layer structure of the film is (A) / (B) A two-layered coextruded multilayer film was obtained in which the thickness of each layer was 15 μm / 15 μm (total 30 μm). The resin layer (A) was subjected to corona treatment, and the surface tension by the wetting reagent was 40 mN / m.

On the surface of the resin layer (A) that has been subjected to corona treatment, a solvent-based acrylic pressure-sensitive adhesive (trade name: Olivevine BPS1109, manufactured by Toyo Ink Chemical Co., Ltd.) is placed on the bar so that the coating amount after drying is 20 μm. It was coated with a coater and dried to form a laminate (B) / (A) / (C1). Next, release paper coated with a silicone release agent was superimposed on processed paper obtained by laminating about 20 μm of polyethylene resin on paper having a basis weight of 74 g / m ² to prepare an easy tear film.

Example 2
COC (1) was used as the resin for the resin layer (A) on the surface. As a resin for the resin layer (A) on the adhesive layer side, a ring-opening polymer of a norbornene-based monomer [“Apel APL8008T” manufactured by Mitsui Chemicals, MFR: 15 g / 10 min (260 ° C., 21.18 N), glass transition temperature : 70 ° C .; hereinafter referred to as “COC (3)”. ] 60 parts by mass and linear low density polyethylene [density: 0.910 g / cm ³ , melting point 95 ° C., MFR: 5 g / 10 min (190 ° C., 21.18 N); hereinafter referred to as “LLDPE”. 40 parts by weight of resin mixture was used. Furthermore, LMDPE was used as the resin for the resin layer (B). These resins or resin mixtures are supplied to three extruders and melt extrusion is performed. The film has a three-layer structure (A) / (B) / (A), and each layer has a thickness of 2 μm. A coextruded multilayer film of / 16 μm / 2 μm (total thickness 20 μm) was obtained. The inner resin layer (A) was subjected to corona treatment, and the surface tension by the wetting reagent was 40 mN / m. An adhesive layer was provided on the surface of the resin layer (A) subjected to corona treatment in the same manner as in Example 1 to obtain an easily tearable film.

Example 3
As resin for the inner resin layer (A) in Example 2, 60 parts by mass of COC (3) and ultra-low density polyethylene [density: 0.880 g / cm ³ , melting point 85 ° C., MFR: 5 g / 10 min (190 ° C. 21.18N); hereinafter referred to as “VLLDPE”. A co-extruded multilayer film was obtained in the same manner as in Example 2 except that 40 parts by mass of the resin mixture was used, and each layer had a thickness of 2 μm / 16 μm / 2 μm (total 20 μm). The resin layer (A) was subjected to corona treatment, and the surface tension by the wetting reagent was 45 mN / m.

  On the surface of the resin layer (A) subjected to the corona treatment, an adhesive layer was applied in the same manner as in Example 1, and release paper was further overlapped to prepare an easy tear label.

Example 4
After applying the urethane adhesive to 2 g / m ² on the surface of the resin layer (A) subjected to the corona treatment of the coextruded multilayer film obtained in Example 3, the basis weight is 74 g / m as a paper substrate. ^Two coated papers were overlaid. Further, an adhesive layer (C1) was formed on the paper base material in the same manner as in Example 1, and release papers were superposed to prepare an easy tear film containing the paper base material.

Example 5
Resin layer (COC (1) was used as the resin for A. Also, LMDPE was used as the resin for the resin layer (B). The layer structure of the film was (A) / (B) / (A) 3 A co-extruded multilayer film was obtained in the same manner as in Example 2 so that the thickness of each layer was 5 μm / 40 μm / 5 μm (total 50 μm), and the resin layer (A) was subjected to corona treatment to give a wetting reagent. The surface tension by was 45 mN / m The surface of the resin layer (A) subjected to corona treatment was processed in the same manner as in Example 1 to obtain an easy tear film.

Example 6
COC (1) was used as the resin for the resin layer (A). Further, LLDPE was used as the resin for the resin layer (B). A coextruded multilayer film was obtained in the same manner as in Example 2 so that the thickness of each layer of the film was 15 μm / 40 μm / 15 μm (total 70 μm). The resin layer (A) was subjected to corona treatment, and the surface tension by the wetting reagent was 45 mN / m. The surface of the resin layer (A) subjected to corona treatment was processed in the same manner as in Example 1 to obtain an easy tear film.

Example 7
As the resin for the resin layer (A), a resin mixture of 50 parts by mass of COC (1) and 50 parts by mass of COC (3) was used. Moreover, LMDPE was used as resin for resin layers (B). A coextruded multilayer film was obtained in the same manner as in Example 2 so that the thickness of each layer of the film was 25 μm / 50 μm / 25 μm (total 100 μm). The resin layer (A) was subjected to corona treatment, and the surface tension by the wetting reagent was 43 mN / m. The surface of the resin layer (A) subjected to corona treatment was processed in the same manner as in Example 1 to obtain an easy tear film.

Example 8
Propylene-α polymerized using a resin mixture of 70 parts by mass of COC (1) and 30 parts by mass of COC (3) as the resin for the resin layer (A) on the surface and a metallocene catalyst as the resin for the resin layer (B) -Olefin random copolymer [Density: 0.900 g / cm ³ , Melting point 135 ° C., MFR: 4 g / 10 min (230 ° C., 21.18 N)]; hereinafter referred to as “MRCP”. ) Was used. COC (3) was used for the inner resin layer (A). A coextruded multilayer film was obtained in the same manner as in Example 2 so that the thickness of each layer of the film was 10 μm / 80 μm / 10 μm (total 100 μm). The resin layer (A) for the inner layer was subjected to corona treatment, and the surface tension with the wetting reagent was 43 mN / m. The surface of the resin layer (A) subjected to corona treatment was processed in the same manner as in Example 1 to obtain an easy tear film.

Example 9
COC (1) was used as the resin for the surface resin layer (A), and COC (3) was used as the resin for the inner resin layer (A). LLDPE was used as the resin for the resin layer (B). A coextruded multilayer film was obtained in the same manner as in Example 2 so that the thickness of each layer of the film was 5 μm / 40 μm / 5 μm (total 50 μm). The resin layer (A) for the inner layer was subjected to corona treatment, and the surface tension with the wetting reagent was 45 mN / m. The surface of the resin layer (A) subjected to corona treatment was processed in the same manner as in Example 1 to obtain an easy tear film.

Example 10
As a resin for the resin layer (A), a ring-opening polymer of 20 parts by mass of COC (1) and 40 parts by mass of COC (3) and a norbornene monomer [“APEL AP6013T” manufactured by Mitsui Chemicals, MFR: 15 g / 10 min. (260 ° C., 21.18 N), glass transition temperature: 125 ° C .; hereinafter referred to as “COC (2)”. 40 parts by weight of resin mixture was used. Moreover, LMDPE was used as resin for the resin layer (B). A coextruded multilayer film was obtained in the same manner as in Example 2 so that the thickness of each layer of the film was 16 μm / 18 μm / 16 μm (total 50 μm). The resin layer (A) was subjected to corona treatment, and the surface tension by the wetting reagent was 43 mN / m. The surface of the resin layer (A) subjected to corona treatment was processed in the same manner as in Example 1 to obtain an easy tear film.

Example 11
As resin for the resin layer (A) on the surface, 70 parts by mass of COC (2) and high-density polyethylene [density: 0.960 g / cm ³ , melting point 128 ° C., MFR: 10 g / 10 minutes (190 ° C., 21.18 N) Hereinafter referred to as “HDPE”. 30 parts by mass of a resin mixture was used. Further, LMDPE was used as the resin for the resin layer (B). As the resin for the inner resin layer (A), a resin mixture of 50 parts by mass of COC (1) and 50 parts by mass of COC (3) was used. A coextruded multilayer film was obtained in the same manner as in Example 2 so that the thickness of each layer of the film was 18 μm / 24 μm / 18 μm (total 60 μm). The resin layer (A) for the inner layer was subjected to corona treatment, and the surface tension with the wetting reagent was 43 mN / m. The surface of the resin layer (A) subjected to corona treatment was processed in the same manner as in Example 1 to obtain an easy tear film.

Example 12
COC (1) was used as the resin for the resin layer (A) on the surface, and COC (3) was used as the resin for the resin layer (A) on the inner layer. LMDPE was used as the resin for the intermediate resin layer (B). Furthermore, VLLDPE was used as the resin for the heat seal layer (C2) to be laminated on the inner resin layer (A). An easily tearable film was obtained in the same manner as in Example 2 so that the thickness of each layer of the film was 10 μm / 10 μm / 10 μm / 10 μm (total 40 μm, base material portion 30 μm).

Example 13
As the resin for the resin layer (A), a resin mixture of 50 parts by mass of COC (1) and 50 parts by mass of COC (3) was used. LMDPE was used as the resin for the intermediate resin layer (C). Furthermore, VLLDPE was used as the resin for the heat seal layer (C2) to be laminated on the inner resin layer (A). An easily tearable film was obtained in the same manner as in Example 2 so that the thickness of each layer of the film was 5 μm / 15 μm / 5 μm / 5 μm (total 30 μm, base material portion 25 μm).

Example 14
The resin layer (A) surface of the easy tear film obtained in Example 13 was subjected to corona treatment, and a solvent-based silicone release agent (trade name: KS725 solvent-type silicone, manufactured by Shin-Etsu Silicone Co., Ltd.) was applied to this surface. Was coated with a bar coater so that the coating amount after drying was 10 μm to form a release layer. The surface of the resin layer made of VLLDPE on the opposite side of the release layer was subjected to corona treatment, and an adhesive layer was formed in the same manner as in Example 1 to prepare an easy tear film having no release paper.

Comparative Example 1
MRCP was used as the resin for the surface resin layer. LMDPE was used as the intermediate layer resin. A coextruded multilayer film was obtained in the same manner as in Example 2 so that the thickness of each layer of the film was 30 μm / 30 μm (total 60 μm). The LMDPE resin layer surface was subjected to corona treatment, and the surface tension by the wetting reagent was 40 mN / m. The surface subjected to the corona treatment was processed in the same manner as in Example 1 to obtain a comparative film.

Comparative Example 2
Paper having a weight of 70 g / m ² was used as the surface material. As the resin for the intermediate layer, low density polyethylene [density: 0.910 g / cm ³ , melting point 115 ° C., MFR: 8 g / 10 min (190 ° C., 21.18 N)]; hereinafter referred to as “LDPE”. ] Was used. Melt extrusion lamination was carried out so that the thickness of the intermediate resin layer was 20 μm to produce a multilayer film. The intermediate resin layer was subjected to corona treatment, and the surface tension with the wetting reagent was 40 mN / m. A film for comparison was obtained by processing the surface of the LDPE subjected to the corona treatment in the same manner as in Example 1.

Comparative Example 3
On the cellophane (# 300) manufactured by Futamura Chemical Co., as a resin for the intermediate layer, melt extrusion lamination was applied in the same manner as in Comparative Example 2 to prepare a multilayer film. A film for comparison was obtained by processing the surface of the LDPE subjected to the corona treatment in the same manner as in Example 1.

Comparative Example 4
A white synthetic paper (PP-based synthetic tack base paper, YUPO, Oji Tac Co., Ltd., 80 μm) was used as a surface base material, and a corona-treated surface was processed in the same manner as in Example 1 to obtain a comparative film.

  Using the films obtained in Examples 1 to 14 and Comparative Examples 1 to 4, the following tests and evaluations were performed.

Hand tearability The tearability was evaluated according to the following criteria to determine whether the film obtained above was torn smoothly by hand without being easily teared. Evaluation was implemented with respect to the longitudinal direction (MD) and the width direction (TD), respectively.
○: Can be easily torn by hand.
X: What cannot be easily torn by hand.

Water resistance The film obtained above was cut into 10 cm squares in length and width, and stored for 24 hours at 40 ° C. and 90% humidity. The film was conditioned at 40 ° C. and 90% humidity for 5 hours, and the film was observed for shrinkage, twist, wave and curl.
○: Shrinkage, twist, no wave ×: Shrinkage, twist, wave

Curling property The film obtained above was cut out 10 cm in length and width and stored for 24 hours at 40 ° C. and 90% humidity. The film was spread on a flat surface and the height at which both end surfaces were rolled up was measured and evaluated according to the following criteria.
○: Less than 3 cm in height Δ: 3 cm or more in height ×: Both ends of the film overlap and become completely rounded

Embossing property Embossing (concavo-convex processing using a metal mold | die) was implemented so that the adhesion layer (C1) or heat seal layer (C2) side of the film obtained above might become concave.
Mold size: 6 points, 3 points in length and 2 points in width, 1 space, 3 spaces. Mold having an inner diameter of 1350 mm and a height (depth) of 0.35 m Evaluation method: 1 month, stored at 25 ° C. and humidity of 50%. The inner diameter was measured and reproducibility / durability was evaluated.
○: Inner diameter change of circular emboss after 1 month is less than 3% compared to immediately after embossing. △: Inner diameter change of circular embossing after 1 month is 3% or more and less than 5% compared to immediately after embossing. The inner diameter change of the emboss is 5% or more compared to immediately after the emboss.

Sharpness For 1 month, the embossed surface (convex surface) of the film, which was stored at 25 ° C. and a constant humidity of 50%, was traced with a finger to evaluate the sharpness of rising.
○: Embossed surface is sharp and convex part is easy to read.
X: The embossed surface is not sharp and the convex portion is difficult to read.

  The results obtained above are shown in Tables 1-2.

Claims (13)

Laminated film having a resin layer (A) containing a cyclic polyolefin resin (a), a resin layer (B) containing a polyolefin resin (b), and an adhesive layer (C1) or a heat seal layer (C2) And the thickness of the base material part except the adhesion layer (C1) or heat seal layer (C2) of the said laminated | multilayer film is 100 micrometers or less, and is on the opposite surface of an adhesion layer (C1) or a heat seal layer (C2). An easily tearable embossed film characterized by having an unevenness by embossing with a convex height or a concave depth of 100 to 500 μm . The easily tearable embossed film of Claim 1 whose surface layer on the opposite surface of the said adhesion layer (C1) or a heat seal layer (C2) is the resin layer (A) containing cyclic polyolefin resin (a).   The easily tearable embossed film according to claim 1, wherein the resin layer (B) / the resin layer (A) / the adhesive layer (C1) or the heat seal layer (C2) are laminated in this order. The easy tear according to claim 1 or 2, wherein the resin layer (A) / the resin layer (B) / the resin layer (A) / the adhesive layer (C1) or the heat seal layer (C2) are laminated in this order. Sex embossed film. The easily tearable embossed film according to claim 3 or 4 , further comprising a layer made of a paper base material between the resin layer (A) and the adhesive layer (C1). The embossed film according to any one of claims 1 to 5 , wherein the cyclic olefin resin (a) is a norbornene polymer. The easily tearable embossed film according to any one of claims 1 to 6 , wherein the resin layer (A) further contains a polyethylene resin and / or a polypropylene resin. The easily tearable embossed film according to any one of claims 1 to 7 , wherein the polyolefin resin (b) is a polyethylene resin or a polypropylene resin. The easily tearable embossed film according to any one of claims 1 to 8 , wherein the thickness of the base material portion excluding the adhesive layer (C1) or the heat seal layer (C2) of the laminated film is in the range of 20 to 80 µm. The easily tearable embossed film according to any one of claims 1 to 9 , wherein a release paper for protecting the adhesive layer (C1) is laminated on the adhesive layer (C1). The easily tearable embossed film according to any one of claims 1 to 10 , wherein a release layer formed by coating silicone is provided on the opposite surface of the adhesive layer (C1), and is wound and stored in a roll shape.   A packaging material comprising the easily tearable embossed film according to any one of claims 1 to 11.   The packaging material according to claim 12, which is a label or a tape.