Lump body and container to which label is bonded using the same

Abstract

To provide: a lump body which is superior in bag breaking properties to the prior art even if a low-viscosity hot melt adhesive is contained in a meltable bag, and which is excellent in solubility (compatibility) with the contents, and in stringiness at the time of coating; and a container to which a label is bonded using the same.SOLUTION: A lump body contains a hot melt adhesive in a meltable bag. The meltable bag is formed of a mixed resin film that contains a low-density polyethylene resin (A) which has a density of 923-930 kg / m3 and an ethylene-vinyl acetate copolymer resin (B). The hot melt adhesive contains a wax (C), and has a viscosity of 500-2,500 mPa s at 140°C.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a mass containing a hot melt adhesive in a melting bag, and to a container to which a label is attached using the mass. [Background technology]

[0002] Hot melt adhesives melt and bond objects together, then allow them to cool and their adhesive properties are immediately apparent, so their advantage of not requiring a curing period has been rediscovered, and their use in packaging and industrial applications is expanding.In addition, with the recent social change that places emphasis on reducing the burden on the environment, the advantage of not requiring solvents or drying processes during use has also been rediscovered, and their use is continuing to expand.

[0003] As the range of applications for hot melt adhesives expands, improvements in workability are required. For example, in the summer, blocks of hot melt adhesive tend to stick together (blocking), forming huge blocks when removed from packaged cardboard boxes, significantly reducing workability. Hot melt adhesives that remain adhesive at room temperature are therefore packaged, transported, and stored in release paper or film, which is then peeled off and discarded when the hot melt adhesive is used. However, the disposal of these release materials has also become an environmental burden and is becoming a problem.

[0004] To address this issue, a specification using a so-called melting bag (lump) has been developed, in which the hot melt adhesive is packaged in a hard material and melted while still packaged when in use (Patent Document 1). Because the hot melt adhesive is melted while still packaged in the melting bag, the lump requires basic performance, such as the solubility (compatibility) of the melting bag and the hot melt, and the ability to break the bag when stored at high temperatures. The practical application of the lump avoids the environmental burden of discarding release liner, and also eliminates the need to peel off the release liner every time the lump hot melt adhesive is melted, dramatically improving workability. Furthermore, in recent years, measures have been taken to prevent blocking, such as increasing the strength of the melt bag (Patent Document 2) or making the shape embossed (Patent Document 3).

[0005] Polyethylene terephthalate bottles (hereinafter referred to as PET bottles) used for beverages and the like typically have labels attached to them, and these labels are often wrapped around the bottle. Hot-melt adhesives are generally used as adhesives for wrapping labels around the bottle. A low-viscosity hot-melt adhesive with a viscosity of 2,500 mPa·s or less at 140°C is preferred for hot-melt adhesives used for PET bottle labels to prevent the hot-melt adhesive from scattering and contaminating the labeler in stringy threads when applied to the label (stringiness) (Patent Document 4). With the increasing use of PET bottles for beverages, there has been a growing demand for a mass of such low-viscosity hot-melt adhesives packaged in a melting bag. However, there have been issues with the stringiness of the molten mass.

[0006] However, the inventors have investigated the inventions described in Patent Documents 1 to 3 and have found that when a low-viscosity hot melt is contained in a melting bag, the hot melt dissolves from the melting bag due to cold flow (a phenomenon in which the hot melt gradually deforms and spreads) during storage, and the melting bag breaks during packaging, exposing the hot melt adhesive to the surface, resulting in the problem of blocking of the lumps together. In other words, no lump had been developed that contained a low-viscosity hot melt in a melt bag, which satisfied the solubility of the melt bag and the hot melt, the bag tearing properties to prevent blocking, and the stringiness during coating. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-002581 [Patent Document 2] International Publication No. 2014 / 194087 [Patent Document 3] Japanese Patent Application Publication No. 2019-065164 [Patent Document 4] Patent No. 4278704 Summary of the Invention [Problem to be solved by the invention]

[0008] Therefore, an object of the present invention is to provide a mass that has better bag-breaking properties than conventional masses, and has excellent solubility (compatibility) with the contents and stringiness during application, even when a low-viscosity hot-melt adhesive with a viscosity of 500 to 2500 mPa·s at 140°C is contained in the melt bag, and to provide a container to which a label is attached using the mass. [Means for solving the problem]

[0009] The present disclosure provides the following masses and containers labeled with the masses: [1]: A mass containing a hot melt adhesive in a melting bag, The density of the melting bag is 923-930 kg / m 3 A mixed resin film comprising a low-density polyethylene resin (A) and an ethylene-vinyl acetate copolymer resin (B), A hot melt adhesive mass containing a wax (C) and having a viscosity of 500 to 2500 mPa·s at 140°C.

[0010] [2]: The above-mentioned mass, in which the content of the ethylene-vinyl acetate copolymer resin (B) in 100% by mass of the mixed resin film is 10 to 50% by mass.

[0011] [3]: The above-mentioned lump, wherein the vinyl acetate content of the ethylene-vinyl acetate copolymer resin (B) is 5 to 30% by mass.

[0012] [4]: Low-density polyethylene resin (A) at 190°C, 2.16 kgf / cm 2 The above aggregates are characterized in that the melt mass flow rate in this case is 1 to 25 g / 10 min.

[0013] [5]: The above-mentioned mass, characterized in that the melting point of the wax (C) is 70 to 150°C.

[0014] [6]: The above-mentioned mass, characterized in that the wax (C) contains at least one of a polyethylene-based wax (C-1) having a melting point of 90 to 150°C and a polypropylene-based wax (C-2) having a melting point of 90 to 150°C.

[0015] [7]: The above-mentioned mass, characterized in that the thickness of the melting bag is 10 to 500 μm.

[0016] [8]: The above-mentioned block, characterized in that it contains a polypropylene wax (C-2) having a melting point of 90 to 150°C, and the wax (C-2) contains a polypropylene wax graft-polymerized with maleic anhydride.

[0017] [9]: The above-mentioned lump, wherein the hot-melt adhesive is an alkali-dispersible hot-melt adhesive.

[0018]

[10] : A container to which a label is attached using the above mass.

[0019]

[11] : The container as described above, characterized in that the container is made of polyethylene terephthalate or glass. DETAILED DESCRIPTION OF THE INVENTION

[0020] The present disclosure will be described in detail below. It goes without saying that other embodiments are also included in the scope of the present disclosure as long as they conform to the spirit of the present disclosure.

[0021] In this specification, a numerical range specified using "to" includes the numerical values ​​before and after "to" as the lower and upper limit values. Unless otherwise noted, each of the various components appearing in this specification may be used independently, either alone or in combination. Furthermore, "parts" and "%" represent "parts by mass" and "% by mass," respectively, unless otherwise specified.

[0022] In this specification, the "viscosity" was measured according to JIS K6862 (Melt viscosity test method for hot melt adhesives). In this specification, the "melt mass flow rate (hereinafter abbreviated as MFR)" was measured according to JIS K7210 (flow test method for thermoplastic plastics). In this specification, the "melting point of the wax" is a value measured using a differential scanning calorimeter (Shimadzu Automatic Differential Calorimeter DSC-60A Plus). In this specification, the "film thickness" was measured using a PEACOCK DIGITAL THICKNESS GAUGE G2-205 manufactured by Ozaki Seisakusho.

[0023] In this specification, the term "hot melt" refers to a material that is solid or viscous at room temperature and melts and softens to become fluid or liquid when heated.

[0024] <Melting bag> The melting bag is used to package hot melt adhesives. However, this does not apply if it can contribute technically to products other than hot melt adhesives. The melting bag used in the present invention has a density of 923 to 930 kg / m 3 The melt bag is made of a mixed resin film containing a low-density polyethylene resin (A) and an ethylene-vinyl acetate copolymer resin (B). The melt bag can be produced by heating and melting the mixed resin film and forming (manufacturing) it into a film using a known method. It is desirable that the film thickness of the melt bag is as uniform as possible.

[0025] From the viewpoint of meltability and tearability, the mixed resin film preferably contains 50 to 90 mass% of low-density polyethylene resin (A), more preferably 70 to 90 mass%, based on 100% mass of the mixed resin film. From the viewpoint of tearability and solubility, the mixed resin film preferably contains 10 to 50 mass% of ethylene-vinyl acetate copolymer resin (B), more preferably 10 to 30 mass%, based on 100% mass of the mixed resin film.

[0026] The thickness of the melting bag is preferably 10 to 500 μm, more preferably 20 to 200 μm, and even more preferably 30 to 100 μm. When the thickness is within the above range, both solubility and bag tearability are easily achieved.

[0027] [Low-density polyethylene resin (A)] The density of low-density polyethylene (A) is 923 to 930 kg / m 3 The density is 923-930 kg / m 3 From the viewpoint of melting property and bag-breaking property, the MFR of the low-density polyethylene resin (A) is preferably from 1 to 25 g / 10 min, more preferably from 7 to 25 g / 10 min.

[0028] [Ethylene-vinyl acetate copolymer resin (B)] The ethylene-vinyl acetate copolymer resin (B) is not particularly limited as long as it is a copolymer of ethylene and vinyl acetate. From the viewpoints of bag rupture resistance and solubility, the vinyl acetate content of the ethylene-vinyl acetate copolymer resin (B) is preferably 5 to 30 mass %, more preferably 10 to 25 mass %. The vinyl acetate content refers to the content (mass %) of vinyl acetate contained in the ethylene-vinyl acetate copolymer resin.

[0029] (Method of manufacturing mixed resin film) The method for producing the film used in the melt bag is not particularly limited as long as it can produce the hot-melt pressure-sensitive adhesive mass desired by the present invention, and examples thereof include known melt extrusion methods such as melt casting, T-die method, and inflation method. The thermoplastic film according to an embodiment of the present invention may be a single-layer film or a multi-layer film consisting of two or more layers. The surface of the thermoplastic film may be roughened to form irregularities, but is not particularly limited as long as a mass containing the hot melt pressure-sensitive adhesive of the present invention can be obtained.

[0030] <Hot melt adhesive> The hot melt pressure sensitive adhesive contains a wax (C) from the viewpoint of bag breaking properties and stringiness, and has a viscosity at 140°C of 500 to 2000 mPa·s, more preferably 700 to 1300 mPa·s.

[0031] Wax Waxes (C) are broadly classified into natural waxes (animal waxes (beeswax, etc.), plant waxes (japanese wax, rice bran wax, etc.), mineral waxes (ozokerite, etc.), petroleum waxes (paraffin wax, microcrystalline wax, etc.)) and synthetic waxes (Fischer-Tropsch wax, polyethylene wax, polypropylene, and acid-modified waxes, etc.). Waxes (C) are used alone or in combination of two or more types.

[0032] The wax (C) preferably has a melting point of 70 to 150°C, from the viewpoint of improving the breakability of the mass containing the hot-melt adhesive in the melt bag.

[0033] The wax (C) preferably contains a polyethylene wax (C-1) having a melting point of 90 to 150° C. and / or a polypropylene wax (C-2) having a melting point of 90 to 150° C. By containing (C-1) and / or (C-2), the bag-breaking properties of the agglomerates can be improved. It is more preferable that the wax (C-2) contains a polypropylene wax having a melting point of 90 to 150° C.

[0034] The polyethylene wax (C-1) is produced from ethylene and includes modified products such as those modified with maleic acid. Examples include Polywax (manufactured by NuCera) and waxes modified with maleic acid. Examples include Sanwax (manufactured by Sanyo Chemical Industries, Ltd.) and Hiwax (manufactured by Mitsui Chemicals, Inc.). Polypropylene waxes (C-2) are mainly produced from propylene and include modified products such as those modified with maleic acid. Examples include block polypropylenes copolymerized with other monomers in blocks, such as Viscol (manufactured by Sanyo Chemical Industries, Ltd.), Hiwax NP series (manufactured by Mitsui Chemicals, Inc.), and Ricosene PP series (manufactured by Client Chemicals). The polypropylene wax (C-2) is preferably a polypropylene wax graft-polymerized with maleic anhydride from the viewpoint of alkali dispersibility of the block.

[0035] In addition to the wax (C), the hot melt adhesive may contain other ingredients such as a thermoplastic elastomer, a tackifier, an oil, a colorant, an antiblocking agent, an inorganic filler, an antioxidant, a bulking agent, a flame retardant, a plasticizer, an antistatic agent, a light stabilizer, an ultraviolet absorber, a heavy metal deactivator, and a fluorescent brightener.

[0036] (thermoplastic elastomer) Thermoplastic elastomers are elastic materials that have properties similar to vulcanized rubber at room temperature, and at high temperatures, like ordinary thermoplastic resins, they are polymeric materials that can be used in existing molding machines as they are.Thermoplastic elastomers have properties that are intermediate between rubber and plastic because they contain both elastic rubber components (soft segments: soft phase) in the molecules and molecular restraint components (hard segments: hard phase) that prevent plastic deformation. Thermoplastic elastomers generally have a polystyrene block and a rubber mid-block, with the polystyrene portion forming physical crosslinks (domains) and serving as crosslinking points, and the middle rubber block providing the product with rubber elasticity. The middle soft segment includes polybutadiene (B), polyisoprene (I), and polyolefin elastomers (ethylene-propylene (EP), ethylene-butylene (EB), butylene-butadiene (BB)), and depending on the arrangement of the hard segment polystyrene (S), they are divided into linear and branched types.

[0037] (tackifier) Examples of tackifiers include phenolic resins, modified phenolic resins, terpene phenolic resins, xylene phenolic resins, cyclopentadiene-phenolic resins, xylene resins, aliphatic, alicyclic, and aromatic petroleum resins, hydrogenated aliphatic, alicyclic, and aromatic petroleum resins, phenol-modified petroleum resins, rosin ester resins, hydrogenated rosin, acid-modified rosin, hydrogenated rosin ester resins, low-molecular-weight polystyrene resins, terpene resins, and hydrogenated terpene resins. Tackifiers with an acid value of 100 to 300 mgKOH / g are particularly suitable for alkali-dispersible hot-melt adhesives. Examples include hydrogenated rosin and acid-modified rosin.

[0038] (oil) The oils are generally used as plasticizers for rubber, thermoplastic elastomers, etc., i.e., process oils produced in petroleum refineries, etc., and are broadly classified into paraffinic process oils, naphthenic process oils, and aromatic process oils. Process oil is a mixture of aromatic rings, naphthenic rings, and paraffin chains, and naphthenic process oil in this application refers to process oil in which naphthenic ring carbons account for 35 to 46% by mass of the total carbon of the process oil. In addition, process oils in which aromatic carbons account for 30% by mass or more of the total carbon are classified as aromatic process oils, and process oils in which paraffin chain carbons account for 50% by mass or more of the total carbon are classified as paraffinic process oils.

[0039] (coloring agent) The colorant can be a commonly known colorant such as red, blue, green, yellow, etc. The colorant may be any of pigments, dyes, and coloring matters, and examples thereof include monoazo-based, dizazo-based, azo-lake-based, benzimidazolone-based, perylene-based, diketopyrrolopyrrole-based, condensed azo-based, anthraquinone-based, quinacridone-based, phthalocyanine-based, and anthraquinone-based colorants, and examples of pigment-based colorants include pigments, perylene-based, monoazo-based, condensed azo-based, isoindolinone-based, titanium oxide, and carbon.

[0040] (Anti-blocking agent) Examples of the anti-blocking agent include silicone, unsaturated fatty acid amides such as stearic acid amide, oleic acid amide, erucic acid amide, oleic acid amide and behenic acid amide.

[0041] (inorganic filler) Examples of inorganic fillers include particles and fibers of metals, metal oxides, metal hydroxides, etc. Specific examples include glass fibers, carbon fibers, calcium silicate, calcium titanate, aluminum borate fibers, flaked glass, talc, kaolin, mica, hydrotalcite, calcium carbonate, zinc carbonate, zinc oxide, calcium hydrogen phosphate, wollastonite, silica, zeolite, alumina, boehmite, aluminum hydroxide, titanium oxide, silicon oxide, magnesium oxide, calcium silicate, alumina sodium silicate, magnesium silicate, carbon nanotube, graphite, copper, silver, aluminum, nickel, iron, calcium fluoride, mica, montmorillonite, and apatite.

[0042] (antioxidant) Examples of antioxidants include pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, diethyl[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]phosphonate, 4,6-bis(octylthiomethyl)-o-cresol, ethylene bis(oxyethylene) bis[3-(5-t-butyl-4-hydroxy-m-tolyl]propionate, tris(2,4-di-t-butylphenyl)phosphite, bis(2,4-di-t-butylphenyl)pentaerythritol diphosphite, etc. These antioxidants may be used alone or in combination of two or more types.

[0043] (filler) Examples of the filler include wet silica, aluminum hydroxide, aluminum oxide, magnesium oxide, montmorillonite, mica, smectite, organically modified montmorillonite, organically modified mica, and organically modified smectite.

[0044] (Flame retardant) Examples of the flame retardant include phosphorus-containing compound flame retardants, halogen-containing compound flame retardants, sulfonic acid metal salt flame retardants, and silicon-containing compound flame retardants.

[0045] (plasticizer) Examples of the plasticizer include phthalate ester-based plasticizers, polyester-based plasticizers, aliphatic dibasic acid ester-based plasticizers, aliphatic monobasic acid ester-based plasticizers, phosphate ester-based plasticizers, citrate ester-based plasticizers, epoxy-based plasticizers, trimellitate ester-based plasticizers, tetrahydrophthalate ester-based plasticizers, glycol-based plasticizers, and bisphenol A alkylene oxide derivatives.

[0046] (light stabilizer) Examples of the light stabilizer include hindered amine compounds and benzoate compounds.

[0047] (ultraviolet absorber) Examples of the ultraviolet absorber include benzophenone-based ultraviolet absorbers, triazine-based ultraviolet absorbers, and benzotriazole-based ultraviolet absorbers.

[0048] (Heavy metal deactivator) Heavy metal deactivators include salicylic acid derivatives, hydrazide derivatives, and oxalic acid amide derivatives.

[0049] (fluorescent whitening agent) Examples of fluorescent brightening agents include stilbene-based, coumarin-based, oxazole-based, and naphthalimide-based agents.

[0050] <Method for manufacturing hot melt adhesive> The manufacturing method of the hot melt pressure sensitive adhesive is not particularly limited as long as it can produce a hot melt pressure sensitive adhesive. An example of the manufacturing method is as follows: A melting pot equipped with a stirrer is heated to about 150°C, and a thermoplastic elastomer is mixed and dispersed into the heated and melted wax (C), oil, etc., and a tackifier is added, followed by further mixing. The hot melt pressure sensitive adhesive can be manufactured by the following steps.

[0051] <Lump> The mass of the present invention is the melting bag containing the hot-melt adhesive. The mass preferably has a weight of 10 g to 5,000 g. A mass within the above range is preferable because it is easy to handle and has excellent workability in terms of the number of times it can be filled. The thickness of the melting bag can be appropriately adjusted depending on the weight.

[0052] The hot-melt adhesive to be contained in the melting bag may be an alkali-dispersible hot-melt adhesive. PET bottles filled with soft drinks, seasonings, etc., and bottles filled with beer, sake, etc., are recycled or reused. The recycling or reuse process usually involves a step of removing the labels attached to the PET bottles or bottles, which are generally removed with a 1.5 to 4 mass % sodium hydroxide aqueous solution at approximately 85 to 95°C. Therefore, alkali-dispersible hot-melt adhesives are used for label applications. The present invention is suitable for a packaged mass of such an alkali-dispersible hot-melt adhesive. The tackifier used in the alkali-dispersible hot-melt pressure-sensitive adhesive preferably contains a tackifier having an acid value of 100 to 300 mgKOH / g, from the viewpoint of alkali dispersibility of the hot-melt pressure-sensitive adhesive. One example is a rosin-based tackifier. The acid value is the number of milligrams of potassium hydroxide (KOH) required to neutralize 1 g of sample, and is a value measured in accordance with JIS K5601-2-1 Acid Value (Titration Method).

[0053] (Method for manufacturing lumps) In the present invention, the method for producing an agglomerate containing a hot-melt pressure-sensitive adhesive is not particularly limited as long as it can produce an agglomerate containing a hot-melt pressure-sensitive adhesive as intended by the present invention. For example, the following method can be exemplified. The hot melt adhesive in a molten state is left at room temperature to solidify, producing a block of hot melt adhesive. The block of hot melt adhesive is then packaged in a mixed resin film (melt bag) to produce a mass. On the other hand, a block of hot melt adhesive may be produced by pouring heat-melted hot melt adhesive onto a mixed resin film and solidifying it, and at the same time, the block of hot melt adhesive may be packaged in a mixed resin film (melt bag).

[0054] ≪Container≫ The container in the present invention refers to a container to which a label is attached using a mass. The material of the container may be glass, plastic, paper, etc., but is not particularly limited. The shape of the container may be round or non-round, such as rectangular. The material of the container is preferably PET or glass, and more preferably PET.

[0055] In the case of PET bottles, labels are applied to a portion of the body of the PET bottle, and also used as roll labels wound around the body of the bottle. OPP film is often used for such roll labels. The labels of the present invention can be well adhered to both those with and without printing on the back side. In the present invention, the agglomerates are coated on a portion of the back side of the label. Coating methods include the open wheel method, the closed gun method, and the direct coat method. The open wheel method and the direct coat method are preferred as methods that do not leave glue on the PET bottle or the like when peeled off.

[0056] The mass of the present invention can be used in the manufacture of hygiene materials, disposable medical drapes, paper, tapes and labels, furniture, textiles, footwear, wood processing or the building industry, for example, roofing membranes or other architectural type laminates. [Example]

[0057] The present invention will be described in more detail below with reference to examples and comparative examples. The present invention is not limited to the following examples. In the examples, unless otherwise specified, "parts" means "parts by mass" and "%" means "% by mass".

[0058] [Method for measuring the acid value of adhesives] The acid value was measured in accordance with JIS K5601-2-1 Acid Value (Titration Method). Specifically, 1 g of sample was precisely weighed and placed in a 250 ml flask. 50 ml of ethanol or a volumetric mixture of ethanol and ether was added, heated to dissolve, and titrated with 0.1 N potassium hydroxide solution (indicator: phenolphthalein) while occasionally shaking. The titration endpoint was determined as the point at which the pale pink color of the solution remained for 30 seconds. A blank test was then performed in the same manner to correct for the acid value, and the acid value was calculated using the following formula: Acid value = [0.1N potassium hydroxide solution consumption (ml) x 5.611] / [sample amount (g)]

[0059] [Method for measuring the melting point of wax (C)] The melting point of wax (C) was measured using a differential scanning calorimeter (Shimadzu Automatic Differential Calorimeter DSC-60A Plus). Approximately 5 mg of sample was taken, cooled to 0°C, heated to 170°C at a heating rate of 10°C / min, and then cooled to 0°C at a cooling rate of -20°C / min. After holding at 0°C for 1 minute, the sample was heated again at a heating rate of 10°C / min, and the exothermic and endothermic heat amounts when heated to 170°C were measured. The melting peak when the wax melted was taken as the melting point.

[0060] [Low-density polyethylene resin (A)] Petrothene 205: Tosoh Corporation, density: 924 kg / m 3 , MFR:3g / 10min Petrothene 230: Tosoh Corporation, density: 925 kg / m 3 , MFR:8g / 10min Petrothene 208: Tosoh Corporation, density: 924 kg / m3 , MFR:23g / 10min Petrothene 1384R: Tosoh Corporation, density: 928 kg / m 3 , MFR: 7.6g / 10min Petrothene 173: Tosoh Corporation, density: 924 kg / m 3 , MFR:0.3g / 10min Petrothene 209: Tosoh Corporation, density: 924 kg / m 3 , MFR:45g / 10min

[0061] [Other low-density polyethylene resins] Novatec LD LC720: Made by Japan Polyethylene Co., Ltd., density: 922 kg / m 3 , MFR: 9.4g / 10min

[0062] [Ethylene-vinyl acetate copolymer resin (B)] Ultrathene 526: Tosoh Corporation, vinyl acetate content: 25% by mass Ultrathene 633: Tosoh Corporation, vinyl acetate content: 20% by mass Ultrathene 710: Tosoh Corporation, vinyl acetate content: 28% by mass Ultrathene 750: Tosoh Corporation, vinyl acetate content: 32% by mass Ultrathene 625: manufactured by Tosoh Corporation, vinyl acetate content: 15% by mass

[0063] Wax Wax (C-1) PW655: Polyethylene wax manufactured by NuCera, melting point: 99°C PW2000: Polyethylene wax manufactured by NuCera, melting point 126°C Wax (C-2) PPMA6252: Ricosene PPMA6252, acid-modified polypropylene wax manufactured by Client Chemicals, melting point: 127°C Viscol 660P: Polypropylene wax manufactured by Sanyo Chemical Industries, melting point: 136°C ·others HNP-9: Paraffin wax manufactured by Nippon Seiro Co., Ltd., melting point: 75°C HNP-11: Paraffin wax manufactured by Nippon Seiro Co., Ltd., melting point: 68°C

[0064] [Antioxidants] IRG1010: Irganox 1010, manufactured by BASF, pentaerythritol tetrakis[3-(3',5'-di-tert-butyl-4'-hydroxyphenyl)propionate]

[0065] [Thermoplastic elastomer] G1650: Kraton G1650, manufactured by Kraton Polymers, SEBS G1643: Kraton G1643, manufactured by Kraton Polymers, SEBS G1652: Kraton G1652, manufactured by Kraton Polymers, SEBS G1726: Kraton G1726, manufactured by Kraton Polymers, SEBS D1118: Kraton D1118, manufactured by Kraton Polymers, SBS

[0066] [Tackifier] RHR-301 (manufactured by China Wuzhou Sun Shine Forestry & Chemicals Co., LTD of Guangxi) Hydrogenated rosin, acid value: 170mgKOH / g KE-604B: Pine Crystal KE-604B (Arakawa Chemical Co., Ltd.) Acrylic modified rosin, acid value: 230 mg KOH / g Alcon M-90 (Arakawa Chemical Co., Ltd.) Hydrogenated petroleum resin, acid value: None

[0067] [oil] N90: N-90 (Idemitsu Kosan), naphthenic process oil PW-90: Diana Process Oil PW-90 (Idemitsu Kosan), paraffin-based process oil PW-380: Diana Process Oil PW-380 (Idemitsu Kosan), paraffin-based process oil

[0068] <Manufacturing mixed resin for melt bags> (Manufacturing example F-1) A pre-blend of 80 parts of LDPE, Petrothene 205, and 20 parts of Ultrathene 710 was placed in the hopper of an IKG co-rotating twin-screw extruder (PMT32-40.5) and fed into the extruder using a screw feeder. The extrusion process was carried out under conditions of a screw rotation speed of 50 rpm and a feed rate of 5 kg / hr, yielding a mixed resin of low-density polyethylene resin and ethylene-vinyl acetate copolymer resin.

[0069] (Manufacturing examples F-2~F-14) Using the compounding ratios shown in Table 1, mixed resins of Production Examples F-2 to F-14 were produced in the same manner as Production Example F-1.

[0070] [Table 1]

[0071] <Manufacturing of hot melt adhesives> (Manufacturing example: HM-1) The hot-melt adhesive was produced as follows: 8 parts of wax (PPMA6252), 17 parts by weight of oil (PW-90), 17 parts by weight of oil (PW-380), and 0.5 parts of antioxidant (IRG1010) were placed in a stainless steel beaker equipped with a stirrer and carefully heated to 130-150°C. After melting, the mixture was stirred to form a homogeneous molten solution. While maintaining the temperature at 130-150°C and continuing to stir, 10 parts of thermoplastic elastomer (G1643) and 10 parts of thermoplastic elastomer (G1652) were gradually added to the molten mixture. After the addition was complete, the mixture was heated and stirred at 130-150°C until 38 parts of tackifier (RHR-301) was completely melted, forming a homogeneous mixture, which was then cooled to produce the hot-melt adhesive.

[0072] (Manufacturing example: HM-2~HM-10) Using the blending ratios shown in Table 2, Production Examples HM-2 to HM-10 were produced in the same manner as Production Example HM-1.

[0073] (Manufacturing example: HM'-1) 20 parts of oil (PW-90), 20 parts of oil (PW-380), and 0.5 parts of antioxidant (IRG1010) were placed in a stainless steel beaker equipped with a stirrer and carefully heated to 130-150°C. After melting, the mixture was stirred to form a homogeneous molten solution. While maintaining the temperature at 130-150°C and continuing to stir, 10 parts of thermoplastic elastomer (G1643) and 10 parts of thermoplastic elastomer (G1652) were gradually added to the molten mixture. After the addition was complete, the mixture was heated and stirred at 130-150°C until 40 parts of tackifier (RHR-301) were completely melted, forming a homogeneous mixture, which was then cooled to produce a hot melt adhesive.

[0074] [Table 2]

[0075] [Example 1] The mixed resin (F-1) was formed into a film on the release-treated layer of a PET / silicone-treated layer using a T-die to obtain a mixed resin film with a thickness of 50 μm. The obtained mixed resin film was cut into a size of 15 cm × 30 cm, folded to enclose 500 g of hot-melt adhesive (HM-1), and the three open sides were heat-sealed to obtain the mass (X) of Example 1.

[0076] [Examples 2 to 19 and Comparative Examples 1 to 5] The aggregates (X) of Examples 2 to 19 and Comparative Examples 1 to 5 were obtained in the same manner as in Example 1, except that the type of mixed resin, the thickness of the mixed resin film, and the type of hot-melt adhesive were changed to those shown in Table 3.

[0077] (Bag breakability) Forty pieces of the lump (X) were placed in a cardboard box measuring 50 cm long x 38 cm wide x 30 cm high, and left in an oven at 40°C for 24 hours, after which the state of the melted bag was visually inspected and evaluated. ◎, ◯, and △ were evaluated as pass, and × was evaluated as fail. [Evaluation criteria] ◎: No breakage of melted bag. Excellent. Good: The melted bag was broken, but the lumps were not adhered to each other. △: The melting bag was broken and the lumps were stuck together, but they could be easily peeled off. No practical problems. ×: The melting bag was broken, and the lumps were stuck together and could not be peeled off. Not practical.

[0078] (Solubility) White hot-melt adhesives were prepared for HM-1 to HM-10 and HM'-1, each containing 1% by weight of titanium oxide based on the total weight of the hot-melt adhesive. The resulting mixed resin film was cut into a 15 cm x 30 cm piece, folded to encase 500 g of the white hot-melt adhesive, and the three open edges were heat-sealed to obtain a mass (Y) containing the white hot-melt adhesive. The mass (Y) was placed in a beaker, heated to 150°C, and stirred at 500 rpm for 1 minute using a stirring blade (IKA Japan, stirring blade R1381). The molten material was then dropped onto black paper and visually evaluated for color unevenness. ◎, ◯, and △ were graded as pass, while × was graded as fail. [Evaluation criteria] ◎: No color unevenness, excellent. 〇: Good, with some color unevenness in some areas. △: Although color unevenness was observed overall, there was no remaining melted part in the melting bag, and there was no problem in practical use. ×: Color unevenness is observed overall, and melted bags remain, making it unsuitable for practical use.

[0079] (Stringiness) The lump was placed in the melting tank of a hot melt gun, heated to 150°C, and intermittently applied 600 times directly across an adherend 30 cm from the tip of the hot melt gun. The weight of the material that fell between the hot melt gun and the adherend was measured to evaluate stringiness. The test conditions were as follows: Discharge temperature: 140℃ Discharge amount: 0.2g / time Discharge time: 0.2 seconds Discharge interval: 0.2 seconds ◎, ◯, and △ were considered to be pass marks, and × was considered to be fail marks. [Evaluation criteria] ◎: Less than 200mg, excellent. 〇: More than 200mg, less than 500mg, good. △: More than 500 mg, less than 1 g, no practical problem. ×: More than 1 g or dissolved lumps clogged the nozzle, making application impossible. Not practical.

[0080] [Table 3]

[0081] [Table 4]

[0082] [Table 5]

[0083] As can be seen from Tables 3 and 4, the aggregates containing a hot-melt adhesive in a melting bag made of a mixed resin film have excellent solubility and bag-breaking properties, and good stringiness during labeling. On the other hand, the comparative examples in Table 5 did not provide aggregates that were excellent in solubility and bag-breaking properties, and good stringiness during labeling.

Claims

1. A mass containing a hot melt adhesive in a melting bag, The density of the melting bag is 923 to 930 kg / m ３ and a mixed resin film containing a low-density polyethylene resin (A) and an ethylene-vinyl acetate copolymer resin (B), A mass in which the hot melt pressure sensitive adhesive contains a wax (C) and has a viscosity of 500 to 2500 mPa·s at 140°C.

2. 2. The lump according to claim 1, wherein the content of the ethylene-vinyl acetate copolymer resin (B) in 100% by mass of the mixed resin film is 10 to 50% by mass.

3. 2. The lump according to claim 1, wherein the ethylene-vinyl acetate copolymer resin (B) has a vinyl acetate content of 5 to 30% by mass.

4. Low density polyethylene resin (A) 190°C, 2.16 kgf / cm ２ 2. The agglomerate according to claim 1, wherein the melt mass flow rate is 1 to 25 g / 10 min.

5. 2. The mass according to claim 1, wherein the melting point of the wax (C) is 70 to 150°C.

6. 2. The lump according to claim 1, wherein the wax (C) contains at least one of a polyethylene wax (C-1) having a melting point of 90 to 150°C and a polypropylene wax (C-2) having a melting point of 90 to 150°C.

7. 2. The mass according to claim 1, wherein the thickness of the melting bag is 10 to 500 μm.

8. 7. The mass according to claim 6, characterized in that it contains a polypropylene wax (C-2) having a melting point of 90 to 150°C, and the wax (C-2) contains a polypropylene wax graft-polymerized with maleic anhydride.

9. 2. The mass according to claim 1, wherein the hot-melt adhesive is an alkali-dispersible hot-melt adhesive.

10. A container to which a label is adhered using the mass according to any one of claims 1 to 9.

11. 11. The container according to claim 10, wherein the material of the container is polyethylene terephthalate or glass.

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