JP2013029583A - Easy-to-tear label - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an easy-to-tear label having an excellent easy-to-tear property with favorable hand-tearable property that allows a user to easily tear it with hands, and cut and separate it without performing any special processing such as perforations and a V-cut, having excellent waterproofness, dimensional stability, and rigidity, and favorably used as a label to be directly stuck to a content such as foods, chemicals, and industrial components or wrappers thereof, and assemblies thereof.SOLUTION: The easy-to-tear label includes a resin layer (A) including a cyclic polyolefin resin (a), and an adhesive layer (B). The label may be superposed with a layer primarily composed of polyolefin resin, a paper base material and the like. From the view point of surface glossiness, a surface opposite of the adhesive layer is preferably a resin layer containing the cyclic polyolefin resin.

Description

  TECHNICAL FIELD The present invention relates to a tape piece or label paper based on a resin film, and more specifically, a cyclic polyolefin-based frozen or refrigerated food, pharmaceutical label, outdoor advertising sticker, and industrial product name (use The method and the label of the precautionary note) are related to an easily tearable label.

  Conventionally, stickers for outdoor advertising stickers, frozen foods, refrigerated foods, pharmaceutical packaging materials and labels attached to containers are films made of thermoplastic resin, especially because they have better water resistance than paper substrates. But polyolefin films have been used. However, such a plastic film is tough and easy to stretch compared to paper, so it is inferior in cutability, and it is difficult to take out and remove by hand when collecting collected articles with tape or label. Have difficulty.

  Various forms are provided as a device for improving such a cut property 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.

Japanese Patent Laid-Open No. 11-349039 JP 2001-348055 A Japanese Patent Laid-Open No. 11-245966

  An object of the present invention has been made in view of the above problems, and is excellent in easy tearability, water resistance, dimensional stability, and rigidity, and is directly applied to contents such as food, medicine, and industrial parts. Or it is providing the easily tearable label which can be used suitably as the label stuck on the package body, those integration bodies, etc.

  As a result of intensive studies to solve the above problems, the present invention has found that a multilayer film having a resin layer containing a cyclic polyolefin resin and an adhesive layer can solve the above problems, and has completed the present invention. It was.

  That is, this invention provides the easily tearable label characterized by having the resin layer (A) containing cyclic polyolefin-type resin (a), and the adhesion layer (B).

  The multilayer film produced by the present invention is a label with good hand cutting properties that can be easily cut and separated by hand without special processing such as perforation and V-cut. Furthermore, since the multilayer film has no change in physical properties due to humidity, curling can be suppressed, dimensional stability is excellent, and blocking is hardly generated. From these things, it is excellent in laminating, printing, and packaging machine suitability, and it is also possible to suppress label waviness due to absorption of humidity. Moreover, it has moderate rigidity and can be suitably applied directly to pharmaceuticals, foods, industrial materials, etc., or a package formed by packaging them.

  The easily tearable label of the present invention is a multilayer film having a resin layer (A) containing at least a cyclic polyolefin resin (a) and an adhesive layer (B). 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 20% by mass or more, particularly preferably 50% by mass or more. Further, “main component” means that the specific resin is contained in an amount of 50% by mass or more with respect to the total mass of the resin component used for forming the resin layer, preferably 70. It means to contain in 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.

  Further, the glass transition point (Tg) of the cyclic polyolefin-based resin (a) is preferably 70 ° C. or higher from the viewpoint of the heat resistance and high rigidity of the easily tearable label to be obtained. When doing, it is preferable that Tg is 200 degrees C or less from the viewpoint of the manufacture by a co-extrusion lamination method and a viewpoint of industrial raw material availability. 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 of the label 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 easy to break and tear easily. In consideration of handleability, 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.

  The easily tearable label of the present invention has a resin layer (A) and an adhesive layer (B) formed into a film using the above-mentioned cyclic polyolefin resin (a), and this adhesive layer (B) Various pressure-sensitive adhesives can be used to form the film, but it is preferable to use 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, and hexane, 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.}

  In the easily tearable label of the present invention, since the resin layer (A) is excellent in tearability, even if the adhesive layer (B) is directly laminated on the resin layer (A), it is also a paper having inherent tearability. A laminate may also be used in combination with a substrate. From the viewpoint of surface glossiness of the obtained label, a combination of a paper base material between the resin layer (A) and the adhesive layer (B), that is, resin layer (A) / paper base material / adhesive layer (B ) Is preferred.

  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.

  When the adhesive layer (B) is laminated directly on the resin layer (A) or on a paper substrate, the polyolefin resin (c) as described below is mainly used on the paper substrate. The method of laminating the resin layer (C) as a component is not particularly limited as the laminating method when the adhesive layer (B) is provided on the resin layer (C). 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 (B) 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 (B) is thin, the initial pressure-sensitive adhesive force is low, and when the pressure-sensitive adhesive layer (B) 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.

  The easily tearable label of the present invention is sufficient if it has at least the resin layer (A) containing the cyclic polyolefin resin (a) and the adhesive layer (B), and is used as described above. Depending on the type of the cyclic polyolefin resin (a), the rigidity is too high, which may cause problems such as dropping or vibration during transportation, and tearing or cutting easily when a label is attached. In such a case, as long as the effects of the present invention are not impaired, the resin layer (A) is formed by using a polyolefin resin that is compatible with the cyclic polyolefin resin (a) and does not contain a cyclic structure. It is preferable to laminate a resin layer (C) containing a polyolefin resin (c) as a main component on the resin layer (A) and use a multilayer film having a multilayer structure as a substrate.

  As said polyolefin resin, the homopolymer or copolymer of a C2-C6 alpha olefin is mentioned. The copolymerization type may be a block copolymer or a random copolymer.

  When the resin layer (A) is used in combination with the above-described cyclic polyolefin resin (a), from the viewpoint of compatibility with the cyclic polyolefin resin (a), a polyethylene resin and / or a polypropylene resin. Is preferably used. Further, the polyolefin resin (c) for forming the resin layer (C) to be laminated on the resin layer (A) does not hinder the easy tear property which is the effect of the present invention, and the resin layer (C) and the resin layer. Similarly, it is preferable to use a polyethylene resin and / or a polypropylene resin from the viewpoint of adhesiveness with (A). Since the polyethylene resin and polypropylene resin used in combination in the resin layer (A) and the polyethylene resin and polypropylene resin that can be preferably used as the main component of the resin layer (C) are the same, hereinafter, Describe without distinction.

As the polyethylene resin, it is preferable to use a polyethylene resin having a density of 0.88 g / cm ² or more and less than 0.950 g / cm ² from the viewpoint of easy tearability.

  Examples of the polyethylene resin include polyethylene resins such as very low density polyethylene (VLDPE), linear very low density polyethylene (VLLDPE), linear low density polyethylene (LLDPE), and low density polyethylene (LDPE), and ethylene-vinyl acetate. Copolymer (EVA), ethylene-methyl methacrylate copolymer (EMMA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methyl acrylate (EMA) copolymer, ethylene-ethyl acrylate-maleic anhydride copolymer Ethylene copolymers such as polymers (E-EA-MAH), ethylene-acrylic acid copolymers (EAA), ethylene-methacrylic acid copolymers (EMAA); and ionomers of ethylene-acrylic acid copolymers , Ethylene-methacrylic acid copolymer ionomer And the like, alone, it may be used by mixing two or more kinds. Among these, VLDPE, VLLDPE, LDPE, and LLDPE are preferable from the viewpoint of easy tearability, workability (film formability), and the like.

  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) when used as a label is good.

As described above, the density of the polyethylene resin is preferably 0.88 to 0.95 g / cm ³ . 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. Moreover, since it can be laminated with the resin layer (A) without using an adhesive resin or the like and 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 obtained label is improved, and the softening temperature can be increased. Therefore, after sticking the 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 label obtained will be favorable, and also the film formability at the time of setting it as a film will also improve.

  In addition to the resin layer (C) containing the polyolefin resin as a main component for the purpose of further improving easy tearability and improving the workability of the label, a cyclic polyolefin resin is used as a main component. It is also possible to laminate a resin layer (D) to be used as a surface layer. At this time, as the main component of the resin layer (D), the cyclic polyolefin resin (a) as the main component of the resin layer (A) in order to secure the heat resistance of the surface and thereby improve the processability of the label. It is preferable that the cyclic polyolefin resin (d) having a higher glass transition point Tg as a main component.

In order to preserve the label of the present invention, it is preferable to laminate a release paper for protecting the adhesiveness of the adhesive layer (B) on the adhesive layer (B). 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.}

  Also, without using release paper, a release layer that prevents sticking to the adhesive layer (B) is provided on the surface opposite to the adhesive layer (B) of the multilayer or single-layer film obtained above. It is also possible to store this in a roll shape.

  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 (B), 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 the roll shape and the adhesiveness as a label is good.

  The surface of the easily tearable label of the present invention is made of a cyclic polyolefin resin or a resin layer containing a polyolefin resin as a main component, as described above, so that it has excellent surface gloss. it can. 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, when the glossiness of the surface is surely ensured, it is preferable that the surface of the label [the surface opposite to the adhesive layer (B)] is a layer containing a cyclic polyolefin resin. When it is desired to laminate the resin layer (C), the resin layer (C) is laminated between the resin layer (A) containing the cyclic polyolefin resin (a) and the adhesive layer (B). Is preferred.

  In particular, as the surface glossiness, for example, in the evaluation based on JIS P8138-1976, it is easy to make the value 90% or more. For example, the resin layer (D) containing the cyclic polyolefin as a main component on the surface is provided. If it is provided and release paper is used to protect the adhesive layer, it may be 100% or more.

  The thickness of the base material portion excluding the adhesive layer (B) of the easily tearable label of the present invention is preferably in the range of 15 to 150 μm, particularly 20 from the viewpoint of the balance between tearability and adhesiveness. It is preferable to be in the range of ˜120 μm. If the thickness of the substrate portion is within this range, stable tearability, moisture resistance, transparency when no paper substrate is used, and the like are easily obtained.

  In addition, when the layer configuration other than the adhesive layer (B) is a multilayer, the ratio of the resin layer (C) containing a polyolefin resin as a main component is in the range of 30 to 90% of the base material portion. , Easy tearability is improved.

  For each of the resin layers (A), (C), and (D), an antifogging agent, an antistatic agent, a thermal stabilizer, a nucleating agent, an antioxidant, a lubricant, an antiblocking agent, Components such as 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 give the processing suitability at the time of label molding and the suitability to an automatic sticking machine, the friction coefficient of the outermost resin layer is preferably 1.5 or less, and 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 label of the present invention, the surface of the outermost resin layer is treated so that the surface tension of the outermost surface is 38 dyne / cm or more, preferably 40 dyne / cm 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 post-process such as printing or aluminum vapor deposition is applied to the label, the coating property of the ink and the adhesive is improved, and the adhesion with the ink, the aluminum, or the 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 label of this invention, For example, when making the base-material part except an adhesion layer (B) into a multilayer structure, resin or resin mixture used for each resin layer is each separately. A co-extrusion method in which it is melted by heating in an extruder, laminated in the desired multilayer structure in a molten state by a method such as a co-extrusion multi-layer die method or a feed block method, and then formed into a film by inflation or a T-die / chill roll method Is mentioned. 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) or (d) used in the present invention and a polyethylene resin as the resin layer (C) are used, the difference between the melting point and Tg may increase between the two. For this reason, the film appearance may be deteriorated during coextrusion, 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 label of the present invention is obtained as a substantially unstretched multilayer film by the above production method, it is possible to perform secondary molding such as deep drawing by vacuum molding, embossing and foil pressing after pasting as a label. Become.

  The application range of the easily tearable label of the present invention is not particularly limited, and examples thereof include tapes and labels used for foods, pharmaceuticals, industrial parts, 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.

  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-based monomer [“Apel APL8008T” manufactured by Mitsui Chemicals, MFR: 15 g / 10 min (260 ° C., 21.18 N), glass transition temperature: 70 ° C .; Hereinafter, it is referred to as “COC (3)”. ] 20 parts by mass, 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”. 80 parts by weight of resin mixture was used. These resins are supplied to a resin layer (A) extruder (40 mm in diameter) and melted at 200 to 230 ° C., and the molten resin is a co-extruded multilayer film manufacturing apparatus of T-die / chill roll method having a feed block. (Feed block and T die temperature: 250 ° C.) and melt extrusion was performed to obtain a film having a thickness of 30 μm. The resin layer (A) was subjected to corona treatment, and the surface tension by the wetting reagent was 40 dyne / cm.

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 (A) / (B). Next, release paper having a basis weight of 74 g / m ² coated with a silicone release agent was superposed to prepare an easy tear label.

Example 2
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. Further, as the resin for the resin layer (C), linear medium density polyethylene [density: 0.930 g / cm ³ , melting point 125 ° C., MFR: 5 g / 10 minutes (190 ° C., 21.18 N); " ] 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 (C) (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 having co-extrusion and carrying out co-melt extrusion, and the layer structure of the film is (A) / (C) A two-layered coextruded multilayer film having a thickness of 4 μm / 16 μm (20 μm in total) was obtained. The resin layer (C) was subjected to corona treatment, and the surface tension by the wetting reagent was 40 dyne / cm.

  An easily tearable label was prepared by forming an adhesive layer on the surface of the resin layer (C) subjected to the corona treatment and overlaying a release paper in the same manner as in the example.

Example 3
As a resin for the resin layer (D) on the surface, 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 referred to as “COC (1)”. ] Was used. As resin for the resin layer (A), 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., 21.18 N), Hereinafter referred to as “VLLDPE”. 40 parts by weight of resin mixture was used. Moreover, LMDPE was used as resin for the resin layer (C). These resins were supplied to the respective extruders, and in the same manner as in Example 2, the film layer structure was a three-layer structure (D) / (C) / (A), and the thickness of each layer was 2 μm / 16 μm. A coextruded multilayer film having a thickness of / 2 μm (total 20 μm) was obtained. The resin layer (A) was subjected to corona treatment, and the surface tension by the wetting reagent was 45 dyne / cm.

  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. Furthermore, the adhesive layer (B) was formed on the paper base material in the same manner as in Example 1, and the release paper was overlaid to prepare an easy tear label including the paper base material.

Example 5
COC (1) was used as the resin for the resin layers (A) and (D). Moreover, LMDPE was used as resin for the resin layer (C). Coextruded multilayer in the same manner as in Example 3 so that the layer structure of the film is (D) / (C) / (A), and the thickness of each layer is 5 μm / 40 μm / 5 μm (total 50 μm). A film was obtained. The resin layer (A) was subjected to corona treatment, and the surface tension by the wetting reagent was 45 dyne / cm. 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 label.

Example 6
As a resin for the resin layer (C), linear low density polyethylene [density: 0.900 g / cm ³ , melting point 85 ° C., MFR: 5 g / 10 min (190 ° C., 21.18 N); hereinafter, “LLDPE” That's it. ] Was used. A coextruded multilayer film was obtained in the same manner as in Example 3 so that the thickness of each layer of the film was 15 μm / 40 μm / 15 μm (total 20 μm). The resin layer (A) was subjected to corona treatment, and the surface tension by the wetting reagent was 45 dyne / cm. 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 label.

Example 7
As the resin for the resin layers (A) and (D), 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 3 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 dyne / cm. 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 label.

Example 8
Propylene 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 (D) on the surface and a metallocene catalyst as the resin for the resin layer (C) of the inner layer -Α-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 3 so that the thickness of each layer of the film was 10 μm / 80 μm / 10 μm (total 100 μm). The resin layer (A) was subjected to corona treatment, and the surface tension by the wetting reagent was 43 dyne / cm. 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 label.

Example 9
COC (1) was used as the resin for the surface resin layer (D), and COC (3) was used as the resin for the inner resin layer (A). LLDPE was used as the resin for the resin layer (C). A coextruded multilayer film was obtained in the same manner as in Example 3 so that the thickness of each layer of the film was 5 μm / 40 μm / 5 μm (total 50 μm). The resin layer (A) was subjected to corona treatment, and the surface tension by the wetting reagent was 45 dyne / cm. 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 label.

Example 10
As the resin for the resin layers (A) and (D), 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. Further, LLDPE was used as the resin for the resin layer (C). A coextruded multilayer film was obtained in the same manner as in Example 3 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 dyne / cm. 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 label.

Example 11
As resin for the resin layer (D) 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 min (190 ° C., 21.18 N) Hereinafter referred to as “HDPE”. 30 parts by mass of a resin mixture was used. Further, LLDPE was used as the resin for the resin layer (C). 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 3 so that the thickness of each layer of the film was 18 μm / 24 μm / 18 μm (total 60 μm). The resin layer (A) was subjected to corona treatment, and the surface tension by the wetting reagent was 43 dyne / cm. 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 label.

Example 12
COC (1) was used as the resin for the surface resin layer (D), and COC (3) was used as the resin for the inner resin layer (A). LMDPE was used as the resin for the intermediate resin layer (C). Furthermore, VLLDPE was used as the resin for the resin layer (C) to be laminated on the inner resin layer (A). A coextruded multilayer film was obtained in the same manner as in Example 3 so that the thickness of each layer of the film was 18 μm / 40 μm / 18 μm / 14 μm (total 90 μm). The resin layer (C) on the surface was subjected to corona treatment, and the surface tension with the wetting reagent was 40 dyne / cm. The surface of the resin layer (C) subjected to corona treatment was processed in the same manner as in Example 1 to obtain an easy tear label.

Example 13
As the resin for the resin layers (A) and (D), 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). VLLDPE was used as the resin for the outermost resin layer (C). A coextruded multilayer film was obtained in the same manner as in Example 3 so that the thickness of each layer of the film was 20 μm / 50 μm / 20 μm / 10 μm (total 100 μm). The resin layer (C) on the surface was subjected to corona treatment, and the surface tension with the wetting reagent was 40 dyne / cm. The surface of the resin layer (C) subjected to corona treatment was processed in the same manner as in Example 1 to obtain an easy tear label.

Example 14
The resin layer (D) of the coextruded multilayer 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. Then, coating was performed with a bar coater so that the coating amount after drying was 10 μm, and a release layer was formed. An adhesive layer was formed on the surface of the resin layer (A) subjected to corona treatment in the same manner as in Example 1 to prepare an easy tear label 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 surface resin layer was subjected to corona treatment, and the surface tension by the wetting reagent was 40 dyne / cm. The corona-treated surface was processed in the same manner as in Example 1 to obtain a comparative label.

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 by the wetting reagent was 40 dyne / cm. A comparative label was obtained by processing the surface of the LDPE subjected to 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 comparative label was obtained by processing the surface of the LDPE subjected to corona treatment in the same manner as in Example 1.

Comparative Example 4
Paper having a weight of 70 g / m ² was used as the surface substrate, and the paper was subjected to corona treatment, and the surface tension by the wetting reagent was 40 dyne / cm. The corona-treated surface was processed in the same manner as in Example 1 to obtain a comparative label.

Comparative Example 5
White synthetic paper (PP-based synthetic tack base paper YUPO manufactured by Oji Tac Co., Ltd., 80 μm) was used as the surface substrate, and the corona-treated surface was processed in the same manner as in Example 1 to obtain a comparative label.

  Using the labels obtained in Examples 1 to 14 and Comparative Examples 1 to 5, the following tests and evaluations were performed.

Hand tearability The tearability was evaluated according to the following criteria as to whether or not the label obtained above was torn easily by hand without being subjected to easy tearing such as cutting. 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 label obtained above was cut out 10 cm in length and width and stored for 24 hours at 40 ° C. and 90% humidity. The humidity was adjusted to 40 ° C. and 90% humidity for 5 hours, and the shrinkage, twist, wave state and curl state of the label were observed.
○: Shrinkage, twist, no wave ×: Shrinkage, twist, wave

Curling property The label obtained above was cut out 10 cm in length and breadth and stored for 24 hours at 40 ° C. and 90% humidity. The label was spread on a flat surface and the height at which both end surfaces were raised 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

Glossiness The label obtained above was measured and evaluated according to a plastic optical property test method (JIS K7105), with the measurement surface being a resin layer (A) or a resin layer (D), and a 60-degree specular glossiness. .
○: 90% or more ×: less than 90

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

Claims (11)

An easily tearable label comprising a resin layer (A) containing a cyclic polyolefin resin (a) and an adhesive layer (B). The easily tearable label according to claim 1, further comprising a layer made of a paper base material between the resin layer (A) and the adhesive layer (B). The easily tearable label according to claim 1 or 2, wherein the cyclic olefin resin (a) is a norbornene polymer. The easily tearable label according to any one of claims 1 to 3, wherein the resin layer (A) further contains a polyethylene resin and / or a polypropylene resin. Furthermore, the easily tearable label of any one of Claims 1-4 in which the resin layer (C) which has polyolefin resin (c) as a main component is laminated | stacked. The easily tearable label according to claim 5, wherein the polyolefin resin (c) is a polyethylene resin or a polypropylene resin. Furthermore, a resin layer (D) mainly composed of a cyclic polyolefin resin (d) having a glass transition point Tg higher than that of the cyclic polyolefin resin (a) is laminated, and the resin layer (D) is bonded to the adhesive layer ( The easily tearable label according to claim 5 or 6, which is a surface layer opposite to B). The easily tearable label according to any one of claims 1 to 7, wherein a release paper for protecting the adhesive layer (B) is laminated on the adhesive layer (B). The easily tearable label according to any one of claims 1 to 7, wherein a release layer formed by coating silicone is provided on the opposite surface of the adhesive layer (B), and is wound and stored in a roll shape. The easily tearable label according to any one of claims 1 to 9, wherein the glossiness of the surface based on JIS P8138-1976 is 90% or more. The easily tearable label according to any one of claims 1 to 10, which is used for collecting and integrating individually packaged packages.