JP4887000B2 - Label for in-mold molding and resin molded product with label - Google Patents

Description

  The present invention relates to in-mold molding in which a resin-molded article with a label is manufactured by differential pressure molding, hollow molding, injection molding, vacuum molding or pressure molding. Specifically, the label and label for in-mold molding The present invention relates to a resin-molded product.

  Conventionally, in order to integrally form a resin-molded container with a label, a blank or label is inserted in advance into the mold, and then the container is molded in the mold by injection molding, hollow molding, differential pressure molding, foam molding, etc. Then, painting or the like is performed on the container (for example, Patent Document 1). Examples of such in-mold labels include gravure-printed resin films, offset multicolor-printed synthetic paper (for example, Patent Documents 2 and 3), or high-pressure low-density polyethylene or ethylene on the back of an aluminum foil. -Aluminum labels that are laminated with vinyl acetate copolymer and gravure printed on the surface of the foil are known.

  The label for in-mold molding is molded in-mold after the product name, manufacturer, sales company name, character, barcode, usage method, and the like are printed. Various printing methods such as sheet-fed offset printing, rotary offset printing, gravure printing, flexographic printing, letter press printing, and screen printing are used as the printing method. Many are used.

  However, in the method of manufacturing a resin-molded article with a label decorated with a label by in-mold molding using the label for in-mold molding, if the antistatic function of the label is insufficient, There was a drawback in that troubles due to static electricity occurred during label production in a low humidity environment. In the label printing process, when the in-mold forming label is printed by the sheet offset printing method, printing trouble has occurred in the sheet processed into the in-mold forming label due to generation of static electricity.

  Sheet-fed offset printing is composed of three parts: a paper feed unit, a printing unit, and a paper discharge unit. Sheets to be printed are supplied to the printing unit one by one by the paper feeding unit, the ink is transferred by the printing unit, sent to the paper discharge unit, and stacked. In the printing section, after a predetermined amount of ink is supplied from the ink fountain according to the pattern, it is supplied to the printing section of the printing plate on which the pattern is drawn, and transferred to a rubber sheet-fed offset printing blanket. The mechanism when ink is transferred to a sheet is shown in FIG. 1. The sheet (1) is placed on a metal impression cylinder (3) synchronized with a rubber sheet offset printing blanket (2). The ink is transferred to the (1) substrate layer surface of the sheet. When the sheet (1) peels from the sheet offset printing blanket (2), static electricity is generated on the surface of the sheet. As a result, as the antistatic performance of the sheet for in-mold label becomes insufficient, the paper alignment becomes uneven due to electrostatic repulsion. Further, when static electricity is accumulated in the paper discharge unit, it takes time for sheet sheets to repel and stack, and the printing speed cannot be increased, which is inefficient.

  In addition, when supplying labels into the mold using the automatic label supply device, the static electricity between the stacked labels is not removed, but two or more labels are simultaneously supplied into the mold, There has been a problem that a resin molded product (defective product) in which the label is bonded to an irregular position is generated, or the label is dropped and cannot be used effectively.

  In order to solve such problems, in-mold molding labels in which a kneading type low molecular weight antistatic agent is kneaded into an ethylene resin that is a heat sealable resin layer of the label, or a heat sealable ethylene resin An antistatic film has been formed by applying a low molecular weight antistatic agent to the surface of the layer and drying it.

  However, both in-mold molding labels have a drawback that the antistatic function has a short long-term durability. In the former in-mold molding label, the antistatic agent component migrates or concentrates on the surface of the heat-sealable resin layer, so that the fusion-bonding performance of the heat-sealable resin to the container is significantly hindered. However, there is a problem that the label is not fused to the container at all or blisters are generated on the label adhered to the container.

In order to solve the above problems, a method of incorporating a polyetheresteramide having a long-lasting and non-adhesive antistatic function into a heat-sealable resin has been proposed (for example, Patent Document 4).
However, they are kneaded and mixed with a heat-sealable resin, extruded with an extruder and a T-die, and in the process of producing labels, they accumulate in the vicinity of the outlet of the T-die and deteriorate, so-called mayani occurs in large quantities, They accumulate and become dirty on the roll surface of the production line that comes into contact with the sealing resin layer. As a result, the scum and dirt come off, causing defects in the film, and the production line is frequently stopped to clean the die tip and roll surface. There was a problem of being forced.
JP 58-69015 A Japanese Patent Publication No.2-7814 JP-A-2-84319 JP-A-11-352888

  The present invention provides a label for in-mold molding and a resin-molded article with a label that give a resin-molded article with a label that has good printing, cutting, and punching processing even under a low humidity environment and has high adhesive strength to the container of the label. For the purpose.

  As a result of repeated studies on an in-mold molding label having antistatic performance in a low humidity environment, the present inventors have found that the following olefin resin base material layer and a heat sealable resin layer having an antistatic layer on the surface It has been found that the above-mentioned problems can be solved by setting the initial frictional band voltage of the olefin-based resin base material layer to a specific range for the Nule index and the blanket for sheet-fed offset printing.

That is, this invention provides the label for in-mold shaping | molding and the resin molded product with a label which have the following structures.
(1) In an in-mold molding label comprising an olefin-based resin base material layer (A) and a heat-sealable resin layer (B) having an antistatic layer on the surface, the surface index of the base material layer (A) (α) ) Is 34 to 74 mN / m, and the Nule index (β) on the surface of the heat-sealable resin layer (B) is 30 to 54 mN / m, and the substrate layer (A) has a relative humidity of 30 ° C. An in-mold molding label, characterized in that the absolute value of the initial frictional band voltage for a sheet-fed offset printing blanket in% is between 0 kV and 15 kV.
(2) The label for in-mold molding according to (1), wherein the half-life of friction band voltage decay of the base material layer (A) is 10 seconds or less.
(3) The in-mold molding label according to (1) or (2), wherein the base material layer (A) has a multilayer structure and is stretched at least in a uniaxial direction.
(4) The label for in-mold molding according to any one of (1) to (3), wherein the base material layer (A) contains a propylene-based resin as a main component.
(5) The label for in-mold molding according to any one of (1) to (4), wherein the base material layer (A) includes at least one of an inorganic fine powder and an organic filler and contains a void.

(6) Two resin compositions in which the base material layer (A) contains 5 to 30% by weight of inorganic fine powder, 3 to 20% by weight of ethylene resin, and 92 to 50% by weight of propylene resin. A resin composition comprising an axially stretched film as a core layer and containing 35 to 65% by weight of inorganic fine powder, 0 to 10% by weight of ethylene resin and 55 to 35% by weight of propylene resin on both sides thereof The label for in-mold molding according to any one of (1) to (5), having a structure in which a uniaxially stretched film is disposed as a front surface layer and a back surface layer.
(7) The heat-sealable resin layer (B) has a density of 0.900 to 0.935 g / cm ³ , a crystallinity (X-ray method) of 10 to 60%, and a number average molecular weight of 10, The high-pressure polyethylene having a viscosity of 000 to 40,000, or the linear linear polyethylene having a density of 0.880 to 0.940 g / cm ³ is contained in any one of (1) to (6) Label for molding.
(8) The inner layer according to any one of (1) to (7), wherein the thickness of the base material layer (A) is 20 to 500 μm and the thickness of the heat-sealable resin layer (B) is 1 to 100 μm. Label for molding.
(9) The label for in-mold molding according to any one of (1) to (8), which has a coat layer containing a pigment on the surface of the base material layer (A).
(10) The in-mold molding label according to any one of (1) to (9), wherein the surface of the base material layer (A) is activated.

(11) The in-mold molding label according to any one of (1) to (10), wherein an antistatic layer is provided on the surface of the coat layer or the base material layer (A).
(12) The antistatic layer provided on the surface of the coat layer or the base material layer (A) contains 0.001 to 10 g of an antistatic agent per unit area (m ² ), and the surface of the heat-sealable resin layer (B) The in-mold molding label according to (11), wherein the antistatic layer comprises 0.001-1 g of an antistatic agent per unit area (m ² ).
(13) The label for in-mold molding according to (12), wherein the antistatic agent includes a polymer type antistatic agent.
(14) The antistatic layer is provided by one or more coating methods selected from the group consisting of a die, a bar, a roll, a gravure, a spray, a blade, an air knife, and a size press (1) to (13) The label for in-mold formation as described in any one.

(15) A resin-molded article with a label in which the label for in-mold molding described in any one of (1) to (14) is adhered to a thermoplastic resin container.
(16) The resin-molded article with a label according to (15), wherein the adhesive strength between the in-mold molding label and the thermoplastic resin container is 200 gf / 15 mm or more.

  The label for in-mold molding of the present invention can be favorably printed, cut and punched even in a low humidity environment. Moreover, the resin-molded article with a label of this invention has high adhesive strength with respect to the container of a label.

BEST MODE FOR CARRYING OUT THE INVENTION

  Hereinafter, the label for in-mold molding and the resin molded product with a label of the present invention will be described in detail. In the present specification, a numerical range represented by using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.

  The in-mold molding label of the present invention comprises an olefin-based resin substrate layer (A) and a heat-sealable resin layer (B) having an antistatic layer on the surface. The wet index (α) on the surface of the base material layer (A) is 34 to 74 mN / m, and the wet index (β) on the surface of the heat-sealable resin layer (B) is 30 to 54 mN / m. Moreover, the absolute value of the initial frictional voltage measured on the surface of the base material layer (A) according to the triboelectric charge decay measurement method described in JIS L 1094 using a sheet offset printing blanket is 0 kV to 15 kV. Is in range.

  Since the base material layer (A) needs ink acceptability in various printing methods such as sheet-fed offset printing, rotary offset printing, gravure printing, flexographic printing, letter press printing, and screen printing, the surface of the base material layer (A) The Nule index is 34 to 74 mN / m, preferably 42 to 72 mN / m. If the surface layer base (A) has a Nure index of less than 34 mN / m, the ink acceptability is insufficient and the printing ink drops off during hollow molding, and if it exceeds 74 mN / m, Sticking together at the ends, it becomes difficult to insert one by one when inserting labels during hollow molding.

  Moreover, the heat-sealable resin layer (B) needs to sufficiently satisfy the adhesive performance between the label and the resin molded product. For this purpose, the Nule index on the surface of the heat-sealable resin layer (B) is 30 to 54 mN / m, and preferably 34 to 52 mN / m. If it is 30 mN / m or more, the affinity between the label and the resin molded product is high and the adhesive strength is practically useful, but if it exceeds 54 mN / m, the polarity of the surface becomes too high, and the label and the resin Adhesive performance with the molded product becomes insufficient and the label is easy to peel off. The Nule index in this specification is a value measured according to “JIS K 6768 (1999): Plastic-film and sheet-wetting tension test method”.

  As an antistatic agent constituting the antistatic layer of the heat-sealable resin layer (B), an antistatic agent such as a low molecular antistatic agent, a high molecular antistatic agent, an electronic conductive antistatic agent, or a conductive filler is used. Can be used. Examples of the low molecular type antistatic agent include glycerin fatty acid ester, alkyl sulfonate, tetraalkylammonium salt, and alkylbetaine. Examples of the high molecular type antistatic agent include quaternary nitrogen-containing acrylic polymer, polyethylene oxide. Polyethylene sulfonate, carbobetaine graft copolymer, and the like. Examples of the electron conductive antistatic agent include polypyrrole and polyaniline. Examples of the conductive filler include tin oxide and zinc oxide. Among these, those containing a polymer type antistatic agent are preferable. The antistatic performance of the heat-sealable resin layer (B) is to prevent problems such as unevenness of the sheet at the paper discharge section in sheet-fed offset printing and sticking between labels in the punching process. is necessary.

  The antistatic ability of the in-mold label can be evaluated by measuring the initial frictional voltage and the half-life of triboelectric charge decay. At the time of sheet-fed offset printing, as shown in FIG. 1, a sheet-fed sheet (1) is sandwiched and printed between a metal impression cylinder (3) synchronized with a rubber sheet-fed offset printing blanket (2). In order to reproduce the static electricity generated in the sheet at this time, the present invention measures and evaluates the initial frictional voltage and the half-life of the frictional charge decay by the following method.

The measurement of the initial frictional voltage in the present invention is based on the triboelectric charge decay measurement method described in 5.4 of “JIS L 1094 (1997): Textile and knitted fabric chargeability test method”. Measure as a label for use. In the measurement, first, the friction surface (4) as shown in FIG. 2 is covered with a blanket offset printing blanket (2) (trade name: R10) made of rubber SRI Hybrid. Fix it. Next, as shown in FIG. 3, the olefin-based resin substrate layer (5) is in contact with the friction element (4), and the heat-sealable resin layer (6) is in contact with the metal friction table (8). The mold forming label (7) is attached to the test piece holder (10) provided on the test piece table (9), fixed on the friction table (8), and the in-mold forming label (7) using a static eliminator. The initial charge of the blanket (2) for sheet-fed offset printing is neutralized. The in-mold molding label (7) is rubbed 5 times at a rate of 2 times per second so that the friction direction becomes one direction, and the in-mold molding label (7) is received simultaneously with the end of the 5 times of friction. Move quickly to the bottom of the part, record the charging voltage and its decay curve, and measure the initial friction charging voltage and the half-life of the triboelectric charge decay from the curve. Incidentally, the power receiving unit is set so that the distance between the power receiving unit and the in-mold molding label (7) is 50 mm when the in-mold molding label (7) is moved. The measurement is performed in an environment of 23 ° C. and 30% relative humidity.
Regardless of whether the value of the frictional voltage is positive or negative, the higher the value, the more likely it is to be charged with static electricity. If the value is too large, it will eventually cause problems during printing and processing. It becomes. Also, the longer the half-life of frictional charge decay, the more difficult the static electricity escapes. If the half-life is too long, it can cause troubles during printing and processing as well.

  When the absolute value of the initial frictional band voltage measured by the above method exceeds 15 kV, the paper discharge section is not aligned in the sheet-fed offset printing, or the label is placed in the mold using the automatic label feeder. When the sheet is supplied, static electricity between the stacked labels is not removed, but two or more labels are simultaneously supplied into the mold, and a defective resin molded product is generated. Therefore, the absolute value of the initial frictional band voltage needs to be in the range of 0 kV to 15 kV, preferably 0 kV to 13 kV, and more preferably 0 kV to 10 kV.

On the other hand, if the half-life of the frictional charge decay is too long, it takes time to align the paper in the paper discharge section in sheet-fed offset printing, which is inefficient because the printing speed cannot be increased. Accordingly, the half-life of triboelectric decay is preferably 10 seconds or less, more preferably 8 seconds or less, and even more preferably 6 seconds or less.
That is, in the present invention, the static electricity generated by friction with the offset printing blanket, which has been a problem in the in-mold molding label, is applied to the heat-sealable resin layer (B ) Surface is effectively improved by providing an antistatic layer, the knowledge that the initial friction band voltage and the decay time of the friction band voltage can be further reduced, and the printability as a label at that time The adhesive strength was completed based on the knowledge that it can be improved by defining the Nure index on the front and back surfaces.

  The base material layer (A) constituting the in-mold molding label of the present invention is a layer containing an olefin resin as a main component. Examples of the olefin resin used for the base material layer (A) include propylene resin, high density polyethylene, medium density polyethylene, polymethyl-1-pentene, ethylene-cyclic olefin copolymer, and the like. May be used as a mixture of two or more. In addition, the olefin-based resin substrate layer (A) of the present invention may have a multilayer structure, or may have a two-layer structure of the core layer (C) and the surface layer (D), or the surface of the core layer (C). It may be a three-layer structure in which a surface layer (D) and a back layer (E) are present on the back side, or a multilayer structure in which another resin film layer is present between the core layer (C) and the front and back layers. .

  The film constituting the base material layer (A) is preferably stretched at least in the uniaxial direction. When the substrate layer (A) is composed of a plurality of layers, it is preferable that at least one layer thereof is stretched. When extending | stretching a several layer, you may extend | stretch separately before laminating | stacking each layer, and you may extend | stretch after laminating | stacking. Further, the stretched layer may be stretched again after being laminated. Furthermore, you may extend | stretch the whole, after shape | molding a heat-sealable resin layer (B) in a base material layer (A).

  Various known methods can be used for stretching, but it is preferable to perform by stretching between rolls utilizing the peripheral speed difference of the roll group. According to this method, the draw ratio can be arbitrarily adjusted. In addition, since the resin is oriented in the flow direction of the film, it is possible to obtain a label having a higher tensile strength and a smaller dimensional change due to the tension during printing than an unstretched film. In the case of an amorphous resin, the stretching temperature can be set to be equal to or higher than the glass transition point of the olefin resin to be used, and in the case of a crystalline resin, can be set to be equal to or higher than the glass transition point of the amorphous portion and below the melting point of the crystalline portion. .

  The heat-sealable resin layer (B) preferably has an adhesive strength of 200 gf / 15 mm or more, more preferably 350 gf / 15 mm or more, and still more preferably 450 to in-mold molded product comprising the label of the present invention and a thermoplastic resin container. It is configured to be 1000 gf / 15 mm. If the adhesive strength is too low, the label may be peeled off due to an impact applied during transportation after the contents of the thermoplastic resin container are filled or during product display.

  Further, the base material layer (A) used in the present invention preferably has a melting point 15 ° C. higher than the melting point of the polyolefin resin constituting the heat-sealable resin layer (B). This is preferable from the standpoint of performance and cost. Examples of such propylene-based resins include propylene homopolymers that exhibit isotactic or syndiotactic stereoregularity, or propylene as a main component, and ethylene, butene-1, hexene-1, and heptene-1,4. -Copolymers with α-olefins such as methylpentene-1 are used. These copolymers may be binary, ternary, or quaternary, and may be random copolymers or block copolymers.

  The base material layer (A) preferably contains at least one of an inorganic fine powder and an organic filler in addition to the olefin resin, and contains a void. As the inorganic fine powder, those having an average particle size of usually 0.01 to 15 μm, preferably 0.01 to 8 μm, more preferably 0.03 to 4 μm can be used. Specifically, calcium carbonate, calcined clay, silica, diatomaceous earth, talc, titanium oxide, barium sulfate, alumina, or the like can be used.

  As the organic filler, those having an average particle diameter after dispersion of usually 0.01 to 15 μm, preferably 0.01 to 8 μm, more preferably 0.03 to 4 μm can be used. As the organic filler, it is preferable to select a different type of resin from the main component olefin resin. For example, polyethylene terephthalate, polybutylene terephthalate, polycarbonate, nylon-6, nylon-6,6, cyclic olefin homopolymer or copolymer of cyclic olefin and ethylene, etc., melting point 120 ° C. to 300 ° C. or glass transition The thing whose temperature is 120 to 280 degreeC can be used. If necessary, the base material layer (A) may further contain a stabilizer, a light stabilizer, a dispersant, a lubricant, a fluorescent whitening agent, a colorant and the like.

  Among these, from the viewpoints of dimensional stability at the time of printing, supply ability of the label into the mold, prevention of heat shrinkage, etc., the substrate layer (A) is composed of 5 to 30% by weight of inorganic fine powder, ethylene. On one side of a biaxially stretched film core layer (C) of a resin composition containing 3 to 20% by weight of a resin and 92 to 50% by weight of a propylene resin, 35 to 65% by weight of an inorganic fine powder; A surface layer (D) made of a uniaxially stretched film of a resin composition containing 0 to 10% by weight of an ethylene resin and 55 to 35% by weight of a propylene resin is bonded. What is this surface layer (D)? Uniaxially stretched film of resin composition containing 35 to 65% by weight of inorganic fine powder, 0 to 10% by weight of ethylene-based resin and 55 to 35% by weight of propylene-based resin on one side of the opposite core layer (C) The back layer (E) made of is bonded Microporous stretched resin films are preferable.

In this stretched resin film, printing is provided on the surface layer (D) side, and the heat-sealable resin layer (B) is provided on the back layer (E) side. The density of the microporous resin stretched film is preferably in the range of 0.65 to 1.02 g / cm ³ .

The resin constituting the heat-sealable resin layer (B) is not particularly limited as long as it has a function of sticking to a resin material constituting a container for sticking a label by heating during in-mold molding. . Preferred examples of the resin include low density or medium density high-pressure polyethylene of a density of 0.900~0.935g / cm ^3, straight-chain linear polyethylene of density 0.880~0.940g / cm ^3, ethylene Vinyl acetate copolymer, ethylene / acrylic acid copolymer, ethylene / acrylic acid alkyl ester copolymer, ethylene / methacrylic acid alkyl ester copolymer (alkyl group having 1 to 8 carbon atoms), ethylene / methacrylic acid copolymer Examples thereof include polyethylene resins having a melting point of 80 to 130 ° C. such as polymer metal salts (Zn, Al, Li, K, Na, etc.).

  Among these, high pressure polyethylene having a density of 10 to 60% and a number average molecular weight of 10,000 to 40,000, or linear linear polyethylene is preferable at the above density. Among these, from the viewpoint of adhesiveness to a resin molded product, 40 to 98% by weight of ethylene and 60 to 2% by weight of α-olefin having 3 to 30 carbon atoms are converted into a metallocene catalyst (especially a metallocene / alumoxane catalyst or, for example, International Publication WO92 / A linear linear polyethylene obtained by copolymerization using a metallocene compound as disclosed in Japanese Patent No. 01723 and a catalyst comprising a compound that reacts with a metallocene compound to form a stable anion. Is optimal. These polyolefin resin may be used individually by 1 type, and may mix and use 2 or more types.

  The heat-sealable resin layer (B) can be embossed as necessary. Embossing causes unevenness on the surface of the heat-sealable resin layer (B), thus preventing blistering during in-mold molding.

  Furthermore, the other well-known additive for resin can be arbitrarily added to the heat-sealable resin layer (B) of this invention in the range which does not inhibit the performance requested | required of a heat-sealable resin layer. Examples of such additives include dyes, nucleating agents, plasticizers, mold release agents, antioxidants, antiblocking agents, flame retardants, and ultraviolet absorbers.

  The heat-sealable resin layer (B) is a method of laminating the heat-sealable resin as a film on the base material layer (A) to form a heat-sealable resin layer, an emulsion of the heat-sealable resin or a heat-sealable resin There is a method of forming a heat-sealable resin layer by applying a resin solution prepared by dissolving a solvent in a solvent such as toluene or ethyl cellosolve to the base material layer (A) and then drying it.

  The thickness of the base material layer (A) is in the range of 20 to 500 μm, preferably 40 to 200 μm. If the wall thickness is too thin, there is a tendency that the insertion of the label into the mold by the label inserter is not fixed at a proper position or the label is wrinkled. On the other hand, if the wall thickness is too thick, the strength of the boundary portion between the in-mold molded resin molded product and the label is lowered, and the drop strength of the resin molded product is inferior. The thickness of each of the above layers is preferably 19 to 170 μm (more preferably 38 to 130 μm) for the (C) layer, preferably 1 to 40 μm (more preferably 2 to 35 μm) for the (D) layer, Preferably it is 1-40 micrometers (more preferably 1-35 micrometers).

  The thickness of the heat-sealable resin layer (B) is preferably 1 to 100 μm, and more preferably 2 to 20 μm. The heat-sealable resin layer (B) needs to be melted by the heat of molten polyethylene or propylene-based resin that can be used as a parison at the time of molding, and the resin molded product and the label must be fused, but sufficient adhesive strength is obtained. Therefore, the thickness of the heat-sealable resin layer (B) is preferably 1 μm or more. On the other hand, if it exceeds 100 μm, the label curls, and sheet-fed offset printing becomes difficult, and it tends to be difficult to fix the label to the mold.

  In order to improve printability on the surface of the base material layer (A), a coating layer containing a pigment can be provided. The pigment coat layer can be formed by performing pigment coating according to a general coated paper coating method. Pigment coating agents used for pigment coating include 30 to 80% by weight of pigments such as clay, talc, calcium carbonate, magnesium carbonate, aluminum hydroxide, silica, calcium silicate, plastic pigment and the like used for ordinary coated paper. And those composed of latex containing 20 to 70% by weight of an adhesive.

  In addition, as an adhesive used in this case, latex such as SBR (styrene / butadiene copolymer rubber), MBR (methacrylate / butadiene copolymer rubber), acrylic emulsion, starch, PVA (polyvinyl alcohol), CMC (carboxymethylcellulose), methylcellulose, etc. can be mentioned. Furthermore, a dispersing agent such as special sodium polycarboxylate such as acrylic acid / sodium acrylate copolymer and a crosslinking agent such as polyamide urea resin can be blended with these compounding agents. These pigment coating agents are generally used as a water-soluble coating agent having a solid content of 15 to 70% by weight, preferably 35 to 65% by weight.

The surface of the base material layer (A) or the coating layer can be activated. The activation treatment is at least one treatment method selected from corona discharge treatment, flame treatment, plasma treatment, glow discharge treatment and ozone treatment, preferably corona treatment and flame treatment. In the case of corona treatment, the treatment amount is 600 to 12,000 J / m ² (10 to 200 W · min / m ² ), preferably 1200 to 9000 J / m ² (20 to 150 W · min / m ² ). If it is less than 600 J / m ² (10 W · min / m ² ), the effect of the corona discharge treatment is insufficient, and when an aqueous solution containing the subsequent antistatic agent is provided by coating, repelling occurs, and 12,000 J / m ^If it exceeds ² (200 W · min / m ² ), the effect of the treatment will reach its peak, and 12,000 J / m ² (200 W · min / m ² ) or less is sufficient. For flame treatment, 8,000~200,000J / m ^2, preferably 20,000~100,000J / m ² is used. If it is less than 8,000 J / m ² , the effect of the flame treatment is insufficient, and repellency occurs when the aqueous solution containing the antistatic agent is applied thereafter, and if it exceeds 200,000 J / m ² , the effect of the treatment reaches a peak. Therefore, 200,000 J / m ² or less is sufficient. If necessary, the activation treatment may be performed on the surface of the heat-sealable resin layer (B).

  The surface of the coat layer or the base material layer (A) is preferably subjected to the activation treatment, and then the antistatic layer is preferably provided. By providing the antistatic layer, feeding and discharging properties on a printing press are possible. Is further improved.

In the present invention, when an antistatic layer is provided on the surface of the coat layer or the base material layer (A), the antistatic layer has a solid content of 0.001 to 10 g, preferably 0.002 to a solid content per unit area (m ² ). It contains 8 g, more preferably 0.002 to 5 g, particularly preferably 0.005 to 0.1 g of an antistatic agent. When the antistatic agent is less than 0.001 g, the antistatic effect does not sufficiently appear, and when it exceeds 10 g, the ink acceptability is insufficient, and the printing ink falls off during the hollow molding process. Similarly, in the antistatic layer on the heat-sealable resin layer (B), the solid content per unit area (m ² ) is 0.001 to 1 g, preferably 0.002 to 0.8 g, more preferably 0.005. Contains ˜0.5 g of antistatic agent. When the antistatic agent is less than 0.001 g, the antistatic effect is not sufficiently exhibited as described above, and when it exceeds 1 g, the adhesive strength between the heat-sealable resin layer (B) and the resin molded product is lowered.

The antistatic layer used in the present invention is, for example, a polymer type antistatic agent having the following constitution (a) alone or mixed with components having ink adhesive properties such as (b) and (c). Can be formed by coating and drying.
(A) Component: Tertiary or quaternary nitrogen-containing acrylic polymer: 100% by weight
(B) Component: Polyimine compound: 0 to 300% by weight
(C) Component: Epichlorohydrin adduct of polyamine polyamide: 0 to 300% by weight

  The tertiary or quaternary nitrogen-containing acrylic polymer as the component (a) is a monomer (i) a component of 4 to 94% by weight, (ii) a component of 6 to 80% by weight, and (iii) ) It is obtained by copolymerizing 0 to 20% by weight of components.

(I) Component: at least one monomer selected from the compounds represented by the following chemical formulas (I) to (VII):

In the above formulas (I) to (VII), R ¹ is hydrogen or a methyl group, R ² and R ³ are each a lower alkyl group (preferably having 1 to 4 carbon atoms, particularly preferably having 1 to 2 carbon atoms). R ⁴ represents a saturated or unsaturated alkyl group or cycloalkyl group having 1 to 22 carbon atoms, X ⁻ represents a quaternized N ⁺ counter anion (eg, a halide, particularly chloride), and M represents an alkali. A metal ion (for example, sodium, potassium), A represents an alkylene group having 2 to 6 carbon atoms.
Among these monomers, it is preferable to use a compound of the chemical formula (VI).

(Ii) Component: (Meth) acrylic acid ester:

上式中、Ｒ¹ は水素またはメチル基を、Ｒ⁵ は炭素数１〜２４のアルキル基、アルキレン基、シクロアルキル基を表わす。具体的には、ブチルアクリレート、カプリルアクリレート、ステアリルメタアクリレート等を挙げることができる。

In the above formula, R ¹ represents hydrogen or a methyl group, and R ⁵ represents an alkyl group, alkylene group, or cycloalkyl group having 1 to 24 carbon atoms. Specific examples include butyl acrylate, capryl acrylate, stearyl methacrylate and the like.

(Iii) Component: Other hydrophobic vinyl monomer:
Specific examples of the hydrophobic vinyl monomer include styrene and vinyl chloride.

Among water-soluble polymers exhibiting particularly preferable antistatic properties among the tertiary nitrogen or quaternary nitrogen-containing acrylic polymer of the component (a), the monomer of the component (i) is represented by the chemical formula (VI). Among these monomers, X ⁻ is Cl ⁻ , which are “Saftmer ST-1000”, “Saftmer ST-1100”, “Saftmer ST-1300”, “Saftmer ST” from Mitsubishi Chemical Corporation. -3200 "as a trade name.

(B) Component: Polyimine compound: 0 to 300% by weight
The polyimine compound as the component (b) is a primer that reinforces the adhesive force. For example, polyethyleneimine having a polymerization degree of 200 to 3,000 represented by the following formula (IX), and an ethyleneimine adduct of polyamine polyamide Or an alkyl-modified product, an alkenyl-modified product, a benzyl-modified product using a halide having a carbon number of 1 to 24, such as an alkyl halide, alkenyl halide, cycloalkyl halide, or benzyl halide as a modifier, or And polyimine compounds selected from the group consisting of modified aliphatic cyclic hydrocarbons and poly (ethyleneimine-urea). These are described in detail in JP-B-2-2910 and JP-A-1-141737.

（式中、Ｚは−ＮＨ−Ｒ⁹またはポリアミンポリアミド残基を表わし、Ｒ⁶ 〜Ｒ⁹ はそれぞれ独立に、水素、炭素数が１〜２４のアルキル基若しくはアルケニル基、シクロアルキル基またはベンジル基であるが、少なくとも一つは水素以外の基を表わし、ｍは０〜３００、ｎ，ｐおよびｑはそれぞれ１〜３００の数値を表わす。）

(In the formula, Z represents —NH—R ⁹ or a polyamine polyamide residue, and R ^{6 to} R ⁹ each independently represents hydrogen, an alkyl or alkenyl group having 1 to 24 carbon atoms, a cycloalkyl group, or a benzyl group. Wherein at least one represents a group other than hydrogen, m represents 0 to 300, and n, p and q each represent a numerical value of 1 to 300.)

(C) Component: Epichlorohydrin adduct of polyamine polyamide: 0 to 300% by weight
The (c) component polyamine polyamide / epichlorohydrin adduct is also a primer that strengthens the adhesive force. For example, a polyamide is reacted with epichlorohydrin from a saturated dibasic carboxylic acid having 3 to 10 carbon atoms and a polyalkylene polyamine. Water-soluble and cationic thermosetting resins obtained in this manner can be mentioned, and details of such thermosetting resins are described in Japanese Patent Publication No. 35-3547. Specific examples of the saturated dibasic carboxylic acid having 3 to 10 carbon atoms include dicarboxylic acids having 4 to 8 carbon atoms, particularly adipic acid.
Specific examples of the polyalkylene polyamine include polyethylene polyamines, particularly ethylenediamine, diethylenetriamine, and triethylenetetramine, and particularly diethylenetriamine.

  In addition to these components, for example, sodium carbonate, sodium sulfate, sodium sulfite, sodium thiosulfate, barium hydroxide, sodium metasilicate, sodium pyrophosphate, sodium tripolyphosphate, sodium monophosphate, potassium alum, ammonium alum, ammonia, etc. Water-soluble inorganic compounds, water-soluble organic solvents such as ethyl alcohol and isopropyl alcohol, surfactants, water-soluble polymerization agents such as ethylene glycol and polyvinyl alcohol, and other auxiliary materials may be blended as necessary. .

  The blending ratio of these components (a), (b) and (c) is such that the polyimine compound (b) is 0 to 300% by weight, preferably 100% by weight of the nitrogen-containing acrylic resin (a), 0 to 200 wt%, and (c) the epichlorohydrin adduct of polyamine polyamide is 0 to 300 wt%, preferably 0 to 200 wt%. By maintaining these compositions, the surface of the olefin-based resin substrate layer and / or the surface of the heat-sealable resin layer is less likely to be charged with static electricity, and the paper supply / discharge performance is improved. These components (a), (b) and (c) are generally used as an aqueous solution having a total solid content of 0.1 to 10% by weight, preferably 0.1 to 5% by weight.

The coating method for providing the antistatic agent aqueous solution (coating agent) on the surface of the heat-sealable resin layer (B), the base material layer (A) or the surface of the coating layer includes a die, a bar, a roll, and a gravure. Coating methods such as spraying, blades, air knives, and size presses, and a combination of these coating methods can be employed. Depending on the viscosity, coating amount, and coating speed of the coating agent, a specified amount of coating agent can be measured using a die, roll, gravure, spray, etc. and transferred to a roll or size press for coating. After transferring a specified amount of coating agent with a die or roll, scrape off the excess coating agent with a bar, blade, air knife, etc., and apply a specified amount of coating agent, die, spray, etc. It is possible to apply a prescribed amount of coating agent directly using As a more specific example, the coating agent is applied at a viscosity of 10 to 1000 cP (0.01 to 1 Ns / m ² ), a coating amount of 1 to 20 g / m ² and a coating speed of 300 m / min or less. As the coating method, an offset gravure method, a spray system, or rotor dampening can be used. The offset gravure method is a combination of gravure and roll. The coating agent is transferred from the gravure plate to the roll, and when the liquid is transferred between the rolls, the gravure plate is removed and the coating agent is smoothed. After being broken, it is transferred to the surface of each layer. In addition, in the spray system that combines spray and size press, the coating agent forms a uniform coating agent film on the size press from the supply device through the spray coating device, and is transferred from the size press to the heat-sealable resin layer. This is preferable as a method for applying a small amount of a coating agent. Rotor dampening is a type of spray coating, in which the coating agent is atomized by a rotor that rotates at high speed by driving a belt and sprayed directly onto the surface of each layer.
The antistatic layer can be obtained by further smoothing, if necessary, after applying the coating agent, or by removing excess water or a hydrophilic solvent through a drying step.

  This in-mold molding label is placed on the inner wall of the lower female die of the differential pressure molding die so that the printing surface of the label is in contact, and then fixed to the inner wall of the die by suction, and then the container molding material resin The melt of the sheet is guided to the upper part of the lower female mold, is subjected to differential pressure molding by a conventional method, and a resin molded product with a label in which the label is integrally fused to the outer wall of the container is molded. As the differential pressure forming, either vacuum forming or pressure forming can be adopted, but in general, differential pressure forming using both of them and utilizing plug assist is preferable. This label can be particularly suitably used as an in-mold label for hollow molding in which a molten resin parison is pressure-bonded to the inner wall of the mold by compressed air. In the resin molded product with a label manufactured in this way, since the label and the resin molded product are integrally formed after the label is fixed in the mold, there is no deformation of the label and the resin molded product main body and the label The adhesive strength of the resin is strong, there is no blister, and the resin-decorated product with a good appearance decorated with a label is obtained.

  The material of the thermoplastic resin container is not particularly limited. For example, high-density polyethylene, medium-density polyethylene, linear low-density polyethylene, ethylene homopolymers such as ultra-low-density polyethylene polymerized by a single-site catalyst, or ethylene / α-olefin copolymers, and branched low-density. Polyolefin resins such as polyethylene, ethylene-vinyl acetate copolymer, and polypropylene, as well as polyethylene terephthalate resin, polyethylene naphthalate resin, polyamide resin, polyvinyl chloride resin, polystyrene resin, and polycarbonate resin can be used. . In addition, a blend of a plurality of types of resins including those other than the above resins can be used, and further, those containing inorganic fillers, other modifiers, and coloring pigments can be used. In addition, the layer structure may be either a single layer or a multilayer, for example, a laminate of a barrier resin such as a saponified ethylene-vinyl acetate copolymer or a polyamide resin, and an adhesive resin with a main layer material associated therewith. It may be.

  The features of the present invention will be described more specifically with reference to examples and comparative examples. The materials, amounts used, ratios, processing details, processing procedures, and the like shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the specific examples shown below.

Example 1
<Manufacture of base material layer>
Propylene homopolymer (trade name “NOVATEC PP MA-8”, melting point 164 ° C., manufactured by Nippon Polypro Co., Ltd.) 67% by weight, high density polyethylene (trade name “NOVATEC HD HJ580”, melting point 134 ° C., Nippon Polyethylene Co., Ltd. )) A resin composition (C) comprising 10% by weight and 23% by weight of calcium carbonate powder having an average particle size of 1.5 μm was melt-kneaded at 250 ° C. using an extruder, and then extruded into a film form from a die. The film was cooled to a temperature of about 50 ° C. This film was heated again to about 150 ° C. and then stretched 4 times in the longitudinal direction using the peripheral speed of the roll group to obtain a uniaxially stretched film serving as a core layer.

  On the other hand, propylene homopolymer (trade name “Novatech PP MA-3”, manufactured by Nippon Polypro Co., Ltd.) 51.5% by weight, high density polyethylene (trade name “Novatech HD HJ580”, manufactured by Nippon Polyethylene Co., Ltd.) 3 A resin composition (D) comprising 42% by weight of calcium carbonate powder having an average particle diameter of 1.5 μm and 3% by weight of titanium oxide powder having an average particle diameter of 0.8 μm is obtained at 240 ° C. using another extruder. The mixture was melt kneaded and extruded onto the surface of the uniaxially stretched film in a film form from a die and laminated to obtain a surface layer / core layer (D / C) laminate.

Furthermore, using different extruders, propylene homopolymer (trade name “Novatech PP MA-3”, manufactured by Nippon Polypro Co., Ltd.) 51.5% by weight, high density polyethylene (trade name “Novatech HD HJ580”, Nippon Polyethylene Co., Ltd.) composition (E) consisting of 3.5% by weight, 42% by weight of calcium carbonate powder having an average particle size of 1.5 μm and 3% by weight of titanium oxide powder having an average particle size of 0.8 μm, and heat An ethylene / 1-hexene copolymer (1) having an MFR of 18 g / 10 min and a density of 0.898 g / cm ³ obtained by copolymerizing ethylene and 1-hexene using a metallocene catalyst as a sealing resin layer. - hexene content 22 wt%, crystallinity 30, the number-average molecular weight 23,000) 75 parts by weight, MFR is 4g / 10 min, density of 0.92 g / cm ^3, crystallinity (X A mixture (B) of 25 parts by weight of a high-pressure method low-density polyethylene having a number average molecular weight of 18,000 is melt-kneaded at 200 ° C. and fed to one coextrusion die and laminated in the die. Then, each film is extruded from the die into a film, and laminated so that the heat-sealable resin layer becomes the outermost layer on the core layer side of the laminate (D / C), and the surface layer / core layer / back layer / heat seal A laminate (D / C / E / B) having a four-layer structure of the conductive resin layer was obtained. The layer B side of the obtained laminate is passed through an embossing roll (150 wires per inch, reverse gravure type) composed of a metal roll and a rubber roll, and a pattern with an interval of 0.17 mm is embossed on the heat-sealable resin layer (B) side. processed.

This four-layered laminate is guided to a tenter oven, heated to 155 ° C., stretched 7 times in the transverse direction using a tenter, then heat-set at 164 ° C., further cooled to 55 ° C. After slitting, a corona discharge treatment was applied to the surface layer (D) side with an intensity of 50 W / m ² / min. Thereafter, an aqueous solution containing 0.5% by weight of the following (a), 0.4% by weight of (b) and 0.5% by weight of (c) on the surface layer side is dried per unit area (m ² ). Coating was carried out by a size press method so that 0.01 g of the antistatic agent contained. Furthermore, on the heat-sealable resin layer (B) side, an aqueous solution containing the following (a) is applied by a spray method so that 0.01 g of an antistatic agent is contained after drying per unit area (m ² ), After drying, antistatic layers were provided on both the front and back sides.

（ｂ） ブチル化変性ポリエチレンイミン
（三菱化学（株）製、ＡＣ−７２（商品名））
（ｃ） 水溶性ポリアミンポリアミドのエピクロルヒドリン付加物
（星光ＰＭＣ（株）製「ＷＳ−４００２」（商品名）） (A) A quaternary nitrogen-containing acrylic terpolymer comprising the following units:

(B) Butylated modified polyethyleneimine (Mitsubishi Chemical Corporation, AC-72 (trade name))
(C) Epichlorohydrin adduct of water-soluble polyamine polyamide (“WS-4002” (trade name) manufactured by Seiko PMC Co., Ltd.)

When the wet index of each surface of the olefin resin base material layer (A or D / C / E) and the heat-sealable resin layer (B) was measured, they were 70 mN / m and 34 mN / m, respectively.
As a result, a six-layer structure having a thickness of about 100 μm (antistatic layer / D / C / E / B / antistatic layer = ultra thin / 30/40/25/5 / ultra thin μm, from cross-sectional observation with an electron microscope) A laminated stretched resin film was obtained.
This laminated stretched resin film having a six-layer structure was cut into a half-size chrysanthemum (636 mm × 470 mm) with a sheet cutter to obtain a sheet for in-mold label.

<Print>
On the surface of the sheet for in-mold label thus obtained, an offset printing machine “Rislon” manufactured by Komori Corporation in an environment of 23 ° C. and 30% relative humidity, and T & K TOKA Co., Ltd. Using UV offset ink “Best Cure” manufactured by the company, UV offset 4-color printing such as product name, manufacturer, sales company name, character, barcode, usage, etc. was performed at a speed of 6,000 sheets / hr. However, the paper alignment at the paper discharge unit was good, and the acceptability of each color ink was also good.

<Punching>
Next, the label portion of the printed in-mold label sheet was punched into a label having a length of 11 cm and a width of 9 cm to obtain an in-mold forming label. When the blocking state of the cut end of the label was confirmed, it was not blocked at all.

<Attachment>
After fixing this in-mold molding label to one of the blow molds using a vacuum so that the surface layer side is in contact with the mold, high-density polyethylene (trade name “NOVATEC HD HB330”, melting point 134 ° C., Japan Polyethylene Co., Ltd.) is melt extruded at 220 ° C. to form a parison, the split mold is clamped, 4.2 kg / cm ² of compressed air is supplied into the parison, and the parison is expanded and shaped into a container. It was heat-sealed with a molding label. After molding, the mold was cooled, the mold was opened, and a resin container with a label having an internal volume of 1000 ml was obtained. There was no fading in the printing of the label attached to the resin container, and no shrinkage of the label or generation of blisters was observed.

(Example 2)
In Example 1, 0.1 g after drying an aqueous solution containing the quaternary nitrogen-containing acrylic terpolymer of (a) as an antistatic layer on the heat sealable resin layer (B) side per unit area (m ² ). A resin container with an in-mold molding label and a label attached thereto was obtained in the same manner as in Example 1, except that the antistatic agent was coated so as to contain. The wet index of each surface of the olefin resin substrate layer (A) and the heat sealable resin layer (B) was 70 mN / m and 50 mN / m, respectively.

(Example 3)
In Example 1, as an antistatic layer on the heat-sealable resin layer (B) side, (a) 1.0% by weight of a quaternary nitrogen-containing acrylic terpolymer and (c) epichlorohydrin addition of a water-soluble polyamine polyamide Product ("WS-4002" (trade name) manufactured by Seiko PMC Co., Ltd.) 0.5% by weight of aqueous solution is coated per unit area (m ² ) so as to contain 0.01 g of antistatic agent. A resin container with an in-mold molding label and a label attached thereto was obtained in the same manner as in Example 1 except that the processing was performed. The wet index of each surface of the olefin resin substrate layer (A) and the heat-sealable resin layer (B) was 70 mN / m and 38 mN / m, respectively.

Example 4
In Example 1, as the antistatic layer on the olefin-based resin layer (A) side, (a) 0.5% by weight of a quaternary nitrogen-containing acrylic terpolymer and (b) butylated modified polyethyleneimine is 0%. An aqueous solution containing 0.5% by weight of 4% by weight and (c) an epichlorohydrin adduct of water-soluble polyamine polyamide was applied so that 0.002 g of antistatic agent was contained after drying per unit area (1 m ² ). Except for the above, a resin container having an in-mold molding label and a label attached thereto was obtained in the same manner as in Example 1. The wet index of each surface of the olefin resin substrate layer (A) and the heat-sealable resin layer (B) was 48 mN / m and 34 mN / m, respectively.

(Comparative Example 1)
In Example 1, except that the antistatic layer on the heat-sealable resin layer (B) side was not applied, the in-mold molding label and the resin container with the label adhered thereto were obtained in the same manner as in Example 1. It was. The wet index of each surface of the olefin resin substrate layer (A) and the heat-sealable resin layer (B) was 70 mN / m and 32 mN / m, respectively.

(Comparative Example 2)
In Example 1, an aqueous solution containing the quaternary nitrogen-containing acrylic terpolymer of (a) as an antistatic layer on the heat-sealable resin layer (B) side was dried per unit area (m ² ) after charging 3 g. A resin container having an in-mold molding label and a label attached thereto was obtained in the same manner as in Example 1 except that the coating was carried out so that the inhibitor contained. The Nule index of each surface of the olefin resin substrate layer (A) and the heat sealable resin layer (B) was 70 mN / m and 62 mN / m, respectively.

(Test example)
About the resin container which stuck the label for in-mold shaping | molding manufactured in Examples 1-4 and Comparative Examples 1-2, and the label, the physical property was measured and evaluated in the following procedures.

(1) Measurement of physical properties (a) Nule index:
In an environment of 23 ° C. and 50% relative humidity, using the “ACCU DYNE TEST” manufactured by Diversified Enterprises, the Nule index (α) on the surface of the base layer (A) of each in-mold molding label and the heat-sealable resin The Nule index (β) of the layer (B) was measured.
(B) Half-life of initial friction band voltage and friction band voltage decay:
It measured using the method mentioned above using Kanebo Engineering Co., Ltd. friction band voltage measuring apparatus EST-8.

(2) Sheet-fed offset printing (c) Ink acceptability:
Using an offset printing machine “Lithrone” manufactured by Komori Corporation, in an environment with a relative humidity of 23 ° C. and a relative humidity of 30%, the paper size of Kikuhan half plate (636 mm × 470 mm) is 1000 at a speed of 6000 sheets / hour. Sheets were printed continuously. Then, the degree of adhesion of the ink after drying with a UV irradiator was evaluated by the following criteria by observing the state when “cello tape (registered trademark)” made by Nichiban was applied and peeled off. did.
○: Ink does not peel off, and the base layer may cause material destruction.
Δ: There is resistance when peeling, but most of the ink is peeled off, causing a problem in practical use.
X: The ink is peeled off completely and there is almost no resistance to peeling.
(D) Paper running performance:
Printing was performed under the above conditions, and the state of paper feed and the degree of paper alignment in the sheet discharge device after UV irradiation were judged according to the following criteria.
○: The paper is smoothly fed and run on the printing press, and the paper is well aligned in the paper discharge unit.
×: Trouble frequently occurs during paper feeding, or paper alignment at the paper output section is poor.

(3) Punching (e) Punching suitability:
100 sheet-printed sheets were stacked, punched with a rectangular blade shape having a length of 11 cm and a width of 9 cm, and the blocking state of the cut surface was observed.
○: Blocking does not occur and there is no problem in practical use. ×: Blocking occurs and is a problem in practical use.

(4) In-mold molding (f) Label / bottle adhesive strength:
A label attached to a container by hollow molding is cut to a width of 15 mm, and the adhesive strength between the label and the container is set to 300 mm / min using a tensile tester “Autograph AGS-D type” manufactured by Shimadzu Corporation. It was determined by peeling T-shaped at a tensile rate of. The criteria for label usage are as follows.
Over 350 (g / 15 mm): No problem in practical use 200 to 350 (g / 15 mm): Slightly weak adhesion, but no problem in practical use Less than 200 (g / 15 mm): Problem in practical use ( g) Generation of blister:
The frequency of blister occurrence of labels pasted on containers by hollow molding was compared.
○: No problem in practical use ×: Problem in practical use

  The label for in-mold molding of the present invention can be favorably printed, cut and punched even in a low humidity environment. For this reason, the label for in-mold molding of the present invention has an advantage that it is easy to manufacture and is actually easy to use. Moreover, the resin-molded article with a label of this invention has high adhesive strength with respect to the container of a label. For this reason, there is no worry that the label peels off during use. Therefore, the present invention has a possibility of being widely used in modern society.

It is a figure which shows the mechanism of sheet-fed offset printing. It is a figure which shows the friction element of a frictional voltage measuring device. It is a figure which shows the measuring mechanism of a frictional voltage measuring device.

Explanation of symbols

1 sheet-fed sheet 2 sheet-fed offset printing blanket 3 impression cylinder 4 friction element 5 olefin resin substrate layer 6 heat-sealable resin layer 7 label for in-mold molding 8 friction table 9 test piece table 10 test piece holder

Claims (19)

In the in-mold molding label in which the olefin-based resin substrate layer (A) , the heat-sealable resin layer (B) , and the antistatic layer are laminated in this order, the surface index (α) of the substrate layer (A) is 34. -74 mN / m, and the Nule index (β) of the surface of the heat-sealable resin layer (B) is 34-52 mN / m, and the base material layer (A) at 23 ° C. and a relative humidity of 30% An in-mold molding label characterized in that an absolute value of an initial frictional voltage with respect to a blanket offset printing blanket is 0 kV to 15 kV.   The label for in-mold molding according to claim 1, wherein the half-life of the frictional voltage decay of the base material layer (A) is 10 seconds or less.   The label for in-mold molding according to claim 1 or 2, wherein the base material layer (A) has a multilayer structure and is stretched in at least a uniaxial direction.   The label for in-mold molding according to any one of claims 1 to 3, wherein the base material layer (A) contains a propylene-based resin as a main component.   The label for in-mold molding according to any one of claims 1 to 4, wherein the base material layer (A) contains at least one of an inorganic fine powder and an organic filler and contains a void.   Biaxially stretched film of resin composition in which base material layer (A) contains inorganic fine powder in a proportion of 5 to 30% by weight, ethylene resin in a proportion of 3 to 20% by weight and propylene resin in a proportion of 92 to 50% by weight Is a uniaxially stretched resin composition containing 35 to 65% by weight of inorganic fine powder, 0 to 10% by weight of ethylene-based resin, and 55 to 35% by weight of propylene-based resin on both sides thereof The label for in-mold molding according to any one of claims 1 to 5, having a structure in which a film is disposed as a front surface layer and a back surface layer. The heat-sealable resin layer (B) has a density of 0.900 to 0.935 g / cm ³ , a crystallinity (X-ray method) of 10 to 60%, and a number average molecular weight of 10,000 to 40. The in-mold molding label according to any one of claims 1 to 6, comprising a high-pressure polyethylene having a density of 1,000,000 or a linear linear polyethylene having a density of 0.880 to 0.940 g / cm ³ .   The thickness of a base material layer (A) is 20-500 micrometers, and the thickness of a heat-sealable resin layer (B) is 1-100 micrometers, For in-mold shaping | molding as described in any one of Claims 1-7 label.   The label for in-mold molding as described in any one of Claims 1-8 which has a coat layer containing a pigment on the surface of a base material layer (A).   The label for in-mold molding according to any one of claims 1 to 9, wherein the surface of the base material layer (A) is subjected to an activation treatment.   The label for in-mold molding according to any one of claims 1 to 10, wherein an antistatic layer is provided on the surface of the base material layer (A) or the coating layer formed on the surface of the base material layer (A). The antistatic layer provided on the surface of the coat layer or the base material layer (A) contains 0.001 to 10 g of an antistatic agent per unit area (m ² ), and is antistatic on the surface of the heat-sealable resin layer (B). The label for in-mold molding according to claim 11, wherein the layer contains 0.001 to 1 g of an antistatic agent per unit area (m ² ).   The in-mold molding label according to any one of claims 1 to 12, wherein an antistatic layer is formed after the surface of the heat-sealable resin layer (B) is embossed.   The label for in-mold molding according to any one of claims 1 to 13, wherein the antistatic agent contains a polymer type antistatic agent.   The label for in-mold molding according to claim 14, wherein the antistatic agent contains a tertiary or quaternary nitrogen-containing acrylic polymer. The antistatic agent is 4 to 94% by weight of at least one monomer selected from the compounds represented by the following formulas (I) to (VII), 6 to 80% by weight of (meth) acrylate monomer, The label for in-mold molding according to claim 15, further comprising a polymer obtained by copolymerizing 0 to 20% by weight of another monomer.

(R ¹ in each of formulas (I) to (VII) represents hydrogen or a methyl group, R ² and R ³ each independently represents an alkyl group having 1 to ⁴ carbon atoms, and R ⁴ represents 1 to 1 carbon atoms. 22 represents a saturated or unsaturated alkyl group or a cycloalkyl group, X ⁻ represents a quaternized N ⁺ counter anion, M represents an alkali metal, and A represents an alkylene group having 2 to 6 carbon atoms. )   The antistatic layer is provided by any one or more coating methods selected from the group consisting of a die, a bar, a roll, a gravure, a spray, a blade, an air knife, and a size press. The label for in-mold molding as described.   A resin-molded article with a label, wherein the label for in-mold molding according to any one of claims 1 to 17 is attached to a thermoplastic resin container.   The resin-molded article with a label according to claim 18, wherein the adhesive strength between the in-mold molding label and the thermoplastic resin container is 200 gf / 15 mm or more.

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