JP4708007B2 - Shrink labels and labeled containers - Google Patents

Description

  The present invention relates to a coating agent, a shrink label using the coating agent, and a container equipped with the label.

  Currently, containers of various shapes are used as containers for beverages such as tea and soft drinks. Examples of such containers include plastic bottles such as PET bottles and metal bottles such as bottle cans. These containers are often equipped with plastic labels for display, decoration, and functionality. Also, in recent years, the ability to follow the containers is good and the display area can be increased. Shrinkable plastic labels (shrink labels) are often used. The shrink label is attached to the container following the container by processing the label into a cylindrical shape and then fitting the shrink label on the container and contracting it with steam or hot air.

  On the other hand, bottles such as the above-mentioned PET bottles and bottle cans are equipped with caps, and are used in the form of opening the bottle by turning the cap and drinking beverages of the contents. However, when the cap is strongly tightened, it is necessary to open the cap with a strong force. At this time, there is a problem that the cap cannot be opened due to empty rotation between the shrink label and the container. For example, a cylindrical container such as a bottle can, particularly a bottle having a small bottle body diameter or a large cap diameter, a bottle having a polyester film laminated on the surface, and the like have a strong tendency as described above.

  As a technique for solving the above-mentioned problem, for example, hot melt or delayed tack type adhesive is applied or printed on the innermost surface, and the label and the bottle are adhered to each other, thereby preventing the label and the bottle from spinning around when the bottle is opened. A method is being tried. However, labels coated with hot melt or delayed tack adhesives are generally wound in rolls and stored and transported as wound bodies, but blocking is likely to occur due to temperature rise and handling is inferior. .

  Japanese Patent Laid-Open No. 2003-335343 proposes a shrink label in which a moisture-sensitive adhesive layer is provided on one side of a heat-shrinkable film, but there is a problem in interlayer adhesion with a printed layer.

JP 2003-335343 A

An object of the present invention is to provide a coating that can quickly exhibit adhesiveness in the presence of water, has excellent interlayer adhesion with a printed layer, and prevents the label from spinning around when the label is opened by bringing the label and container into close contact with each other. An agent, a shrink label using the coating agent, and a container equipped with the label are provided.
Another object of the present invention is to provide a shrink label mounting method capable of efficiently mounting a shrink label having the above characteristics to a container.

  As a result of intensive studies to achieve the above-mentioned object, the present inventors have used a coating agent having a specific configuration, thereby providing a shrink label having high blocking resistance, interlayer adhesion with a printed layer, and excellent adhesive properties. It is found that the label can be closely attached to the container without providing a separate process when the label is attached to the container, and the empty rotation of the label at the time of opening can be effectively prevented. Was completed.

That is, the present invention is a shrink label in which a printing layer and a coating layer are laminated in this order on at least one surface of a heat-shrinkable film, and the coating layer is water-soluble so that it can exhibit adhesiveness in the presence of water. The outermost surface of the label formed of a coating agent containing an adhesive resin and at least one thermoplastic resin selected from an acrylic resin, a urethane resin, a vinyl chloride-vinyl acetate copolymer resin, and a cellulose resin And the printed layer contains a binder resin selected from an acrylic resin, a urethane resin, a vinyl chloride-vinyl acetate copolymer resin, and a cellulose resin, and the thermoplastic layer in the coating layer. The combination of the resin and the binder resin in the printed layer (regardless of the order of right and left) is (1) acrylic resin and polymer (2) Combination of urethane resin and urethane resin, (3) Combination of vinyl chloride-vinyl acetate copolymer resin and vinyl chloride-vinyl acetate copolymer resin, (4) Cellulose system A combination of a resin and a cellulose resin, (5) a combination of a vinyl chloride-vinyl acetate copolymer resin and an acrylic resin, or (6) a combination of a cellulose resin and an acrylic resin, Provide shrink labels .

The present invention also provides a labeled container in which the shrink label is attached to a cylindrical container.

In this specification, in addition to the above-described invention, (i) at least one heat selected from water-soluble adhesive resins, acrylic resins, urethane resins, vinyl chloride-vinyl acetate copolymer resins, and cellulose resins. (Ii) a shrink label in which a printing layer and a coating layer are laminated in this order on at least one surface of a heat-shrinkable film, and the coating layer is formed of the coating agent. A shrink label provided on the outermost surface of the label, (iii) a method of attaching the shrink label to the container in the presence of water, and (iv) the shrink label A container with a label attached to a cylindrical container will also be described.

  According to the coating agent of the present invention, it is possible to form a coating layer that exhibits adhesiveness with water and is excellent in interlayer adhesion with the printed layer. The shrink label provided with this coating layer on the outermost surface adheres to the surface of the cylindrical container through the coating layer that exhibits adhesiveness in the presence of water, and therefore prevents the label and container from spinning around when the container is opened. Can do.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic sectional view showing an example of the shrink label of the present invention. In the shrink label 1 shown in FIG. 1, a printed layer 3 and a coating layer 4 are laminated in this order on one side of a heat-shrinkable film 2.

  As a raw material of the heat-shrinkable film 2, what is normally used as a material of a heat-shrinkable film can be used, for example, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), etc. Examples thereof include polyester resins; polyolefin resins such as polyethylene and polypropylene; polystyrene resins such as styrene-butadiene copolymers; polyvinyl chloride resins and polyvinylidene chloride resins. These materials can be used alone or in admixture of two or more. Among these, a film made of polystyrene resin, polyester resin, or polyvinyl chloride resin is preferable. These heat-shrinkable films may be composed of either a single layer film or a multilayer film.

  The heat-shrinkable film 2 is stretched in at least one direction (for example, the transverse direction) and exhibits heat-shrinkability in that direction. The stretching treatment is performed using a tenter method, a tube method, or the like, for example, at a temperature of about 70 to 100 ° C., 2.0 to 8.0 times, preferably 3.5 to 6.0 times in the main stretching direction. It is performed by stretching to a certain extent. In a direction orthogonal to the main stretching direction, the film may be stretched about 1.1 to 1.5 times. The heat shrinkage rate in the main stretching direction of the heat-shrinkable film 2 is, for example, about 10 to 80%, preferably about 15 to 70% at 95 ° C. (immersion in warm water for 10 seconds). The heat shrinkage rate can be adjusted by appropriately selecting stretching conditions such as the type of resin constituting the heat shrinkable film and the stretching ratio. For example, when a heat-shrinkable film stretched mainly in one direction is formed into a cylindrical shape with the main stretch direction as the circumferential direction, a shrink label having heat-shrinkability in the circumferential direction can be formed.

  The surface of the heat-shrinkable film 2 may be subjected to conventional surface treatment such as corona discharge treatment or primer treatment (undercoat treatment) as necessary. The thickness of the heat-shrinkable film can be selected from the range of, for example, about 10 to 80 μm, preferably about 20 to 60 μm, from the viewpoint of shrinkage stress and cost. Moreover, the heat-shrinkable film 2 may use a foamed film of the resin, and the thickness in the case of the foamed film is, for example, 80 to 500 μm, preferably 80 to 300 μm.

  The printing layer 3 is a layer displaying a product name, an illustration, handling precautions, and the like, and can be formed by a conventional printing method such as gravure printing or flexographic printing. The printing ink used for forming the printing layer is composed of, for example, a pigment, a binder resin, and a solvent. Examples of the binder resin include acrylic, urethane, polyamide, vinyl chloride-vinyl acetate copolymer, cellulose, and nitrocellulose. A general resin such as a system can be used. The thickness of the printing layer 3 is not particularly limited and is, for example, about 0.1 to 10 μm.

  The coating layer 4 in this invention is provided in the outermost surface of a label, and comprises a contact surface with a to-be-adhered body (container etc.). The coating layer 4 is formed of a coating agent containing a water-soluble adhesive resin and at least one thermoplastic resin selected from an acrylic resin, a urethane resin, a vinyl chloride-vinyl acetate copolymer resin, and a cellulose resin. Has been.

  The print layer 3 and the coating layer 4 do not need to be provided on the entire surface of the heat-shrinkable film.

  As the water-soluble adhesive resin, a resin that is soluble in water and an organic solvent and can exhibit adhesiveness in the presence of water is used. As said organic solvent, the solvent etc. which are normally used for printing inks, such as gravure printing and flexographic printing, can be used, for example, acetates, such as ethyl acetate, n-propyl acetate, isobutyl acetate, and n-butyl acetate; Alcohols such as methanol, isopropyl alcohol (IPA), n-propanol (NPA), isobutanol and Sec-butanol; ketones such as methyl ethyl ketone (MEK) and methyl isobutyl ketone (MIBK); aliphatic carbonization such as hexane and octane Hydrogen; Alicyclic hydrocarbons such as cyclohexane; Aromatic hydrocarbons such as toluene and xylene; Glycols such as ethylene glycol and propylene glycol; Propylene glycol monomethyl ether (PGM), Propylene glycol monobutyl ether, etc. Recall ether; and glycol ether esters such as propylene glycol monomethyl ether acetate.

  Specific examples of such water-soluble adhesive resins include polyvinyl alcohol (PVA), ethylene vinyl alcohol (EVA); polyalkylene glycols such as polyethylene glycol; methyl cellulose, ethyl cellulose (EC), hydroxypropyl cellulose (HPC). Water-soluble cellulose resins such as starch, amylose, amylopectin, dextrin, and derivatives thereof, and the like. Of these, HPC, EC, and PVA are preferable because they can exhibit high adhesive strength. In particular, HPC having a hydroxyl value in the range of 50 to 70 (mg-KOH / g) is preferable because it can exhibit high adhesive strength. The weight average molecular weight of water-soluble adhesive resin can be suitably selected from the range which can express adhesiveness, for example, is 50,000-150,000, Preferably it is about 70,000-140,000. These water-soluble adhesive resins may be used alone or in combination.

  The acrylic resin, urethane resin, vinyl chloride-vinyl acetate copolymer resin and cellulose resin are all thermoplastic resins commonly used as a base polymer (binder resin) in printing ink. For this reason, by adding to a coating agent, the interlayer adhesiveness of the adjacent printing layer 3 and the coating layer 4 can be improved, and the binder resin of the printing layer 3 and the thermoplastic resin of the coating layer 4 are all or It is even better if they are the same in some. A thermoplastic resin can also be used individually or in combination. Among them, an acrylic resin is preferable from the viewpoint of compatibility with the water-soluble adhesive resin, and in particular, the glass transition temperature (Tg) is about 20 to 130 ° C. (preferably 30 to 120 ° C.), and the weight average molecular weight. Is preferably an acrylic resin having about 1000 to 120,000 (preferably 5000 to 110000). As an acrylic resin having particularly good compatibility with the water-soluble adhesive resin, a trade name “ARUFON UH-2140” manufactured by Toagosei Co., Ltd. is commercially available.

  The main feature of the coating agent of the present invention is that a water-soluble adhesive resin and a thermoplastic resin are used in combination. The water-soluble adhesive resin is a component that develops adhesiveness in the presence of water and imparts adhesion to the container, and the thermoplastic resin is a component that can improve interlayer adhesion with the printing layer.

  According to the coating agent composed of the water-soluble adhesive resin alone, it is possible to provide adhesion to the container, but the adhesion to the printing layer is poor and the printing layer is dissolved when the coating agent is dissolved in water (water vapor). Therefore, the coating agent partially flows out and the coating layer disappears in a wide range, or the coating layer peels off from the printing layer. As a result, the adhesiveness to the container cannot be exhibited sufficiently, and a gap between the container and the shrink label is generated, causing the label to be idle. Moreover, the adhesiveness with respect to a container is not acquired with the coating agent which consists of a thermoplastic resin alone.

  On the other hand, when the water-soluble adhesive resin and the thermoplastic resin are used in combination, the above-mentioned adverse effects can be avoided because the adhesion to the printing layer is improved, and the amount of the relatively expensive water-soluble adhesive resin used This is advantageous in terms of cost. In this case, although the adhesive strength is lower than when the water-soluble adhesive resin is used alone, there is no problem because the adhesiveness is exerted with a strength that can prevent the label from spinning when the container is opened. In addition, the label is peeled after use for recycling the container, but if the adhesive strength is too high, the coating layer or printed layer remains on the container surface even after the label is peeled off (adhesive residue occurs). Although there is a problem, the coating agent of the present invention does not cause such a problem.

  The mixing ratio of the water-soluble adhesive resin and the thermoplastic resin can be appropriately selected according to workability (applicability), adhesive strength, cost, ease of peeling, etc., and water-soluble adhesive resin / thermoplastic resin (weight) The ratio is, for example, about 0.1 / 99.9 to 50/50, preferably about 0.1 / 99.9 to 40/60.

  Depending on the purpose, the coating agent improves the adhesion by adding sugar alcohols such as sorbitol and sorbitol acetate and derivatives thereof (hereinafter sometimes referred to as “sugar alcohols”), and more reliably free-running. Can be prevented. The sugar alcohol may be a solid in the form of a powder or the like, but an aqueous solution (for example, an aqueous solution having a concentration of 30 to 90% by weight, preferably 40 to 85% by weight) previously dissolved in water from the viewpoint of handleability. It is suitably used in the form. The amount of sugar alcohols added is, for example, 0.1 to 30 parts by weight, preferably 0.5.5 parts by weight with respect to 100 parts by weight of the resin component (total of water-soluble adhesive resin and thermoplastic resin). ~ 20 parts by weight.

  In addition to the above, the coating agent includes a lubricant (resin, wax, silicone oil, etc.), an anti-settling agent (such as an amide anti-settling agent), an antifoaming agent, a dispersion stabilizer (such as a surfactant), a colorant ( Pigments, dyes, etc.), fillers, antioxidants, ultraviolet absorbers, antistatic agents and the like. In general, the shrink label is printed with white solid on the back side of the display in order to clearly display printed characters and images by preventing show-through. Therefore, when the coating layer 4 is formed using a coating agent containing a white pigment, the white solid printing can be replaced, which is advantageous in the production process. At this time, the blending amount of the white pigment is preferably 20 to 50% by weight.

  The coating agent is prepared by dissolving or dispersing a water-soluble adhesive resin, a thermoplastic resin, and sugar alcohols and other additives as required in a solvent. The solvent is not particularly limited as long as it can dissolve the resin components (water-soluble adhesive resin and thermoplastic resin), and examples thereof include organic solvents and water. As the organic solvent, an organic solvent that can dissolve the above resin component satisfactorily and is compatible with water is used. Preferably, an organic solvent that can be easily volatilized in the drying step after coating is used. Among these, alcohol solvents such as ethanol and isopropyl alcohol, which are organic solvents having low toxicity, and ester solvents such as ethyl acetate and butyl acetate are preferable. In particular, isopropyl alcohol, ethyl acetate, and a mixture thereof are preferably used in terms of volatility. These solvents may be used alone or in combination of two or more.

  The coating agent can be prepared, for example, by adding the above-mentioned components of the coating agent to a single solvent or a mixed solvent in which two or more kinds are combined, and dissolving or dispersing by stirring. When added to the solvent, the component may be in the form of a solid such as powder or granules, or may be in any form such as water or a solution dissolved in an appropriate solvent.

  Generally, a water-soluble adhesive resin dissolves well in water or an alcohol solvent. On the other hand, depending on the type of thermoplastic resin, when a solid such as powder is added to an aqueous solvent such as water or an alcohol solvent, the solution is gelled and the dispersibility and coating workability are significantly impaired. When using a thermoplastic resin having the above characteristics, prepare a solution (thermoplastic resin solution) in which a solid thermoplastic resin is previously dissolved in a non-aqueous solvent such as an ester solvent, and then water or an alcohol solvent. It is preferable to mix with. Specifically, for example, a method of mixing an ethyl acetate solution of a thermoplastic resin prepared in advance with an isopropyl alcohol solution of a water-soluble adhesive resin can be mentioned. In addition, sugar alcohols such as sorbitol are often used in the form of an aqueous solution. However, when the aqueous solution is added to a thermoplastic resin having the above characteristics or the resin solution, the mixed solution gels. It is preferable to add to water or an alcohol solution containing an adhesive resin.

  When a thermoplastic resin having no properties as described above is used, mixing is also possible when a powdered thermoplastic resin is added to an alcohol solvent together with a water-soluble adhesive resin or an aqueous solution of a sugar alcohol. A coating agent that is uniform and excellent in coating workability can be prepared without causing the solution to gel or separate. As such a thermoplastic resin, for example, a trade name “ARUFON UH-2140” manufactured by Toagosei Co., Ltd. is commercially available for acrylic resins.

  The coating layer 4 can be formed by printing the coating agent having the above-described structure by a conventional method such as gravure printing or flexographic printing. The coating layer 4 thus formed does not exhibit adhesiveness until it comes into contact with water, and has excellent handling properties because it has blocking resistance.

  The thickness of the coating layer 4 can be appropriately selected within a range in which the above characteristics can be exhibited, and is, for example, 0.5 to 5 μm, preferably 1 to 3 μm.

  In addition, the shrink label of this invention should just have the printing layer and the coating layer formed in one side of the heat-shrinkable film, and may have another layer. As other layers, for example, a resin layer, an anchor coat layer, a primer coat layer, an adhesive layer, an adhesive resin layer, and the like can be provided, and layers such as a nonwoven fabric, paper, and plastic can be laminated. These layers may be provided on the other surface of the heat-shrinkable film, between the heat-shrinkable film and the printed layer.

  In the labeled container of the present invention, the shrink label of the present invention is mounted on a cylindrical container. Examples of the cylindrical container include a bottle-shaped container whose container body has a circular cross section (including an ellipse and a polygon close to a circle). Such cylindrical containers include various bottles such as plastic bottles, glass bottles, and metal bottle cans. In the present invention, the outermost surface of the cylindrical container may be subjected to easy-slip treatment. For example, a bottle can in which a polyester film including a lubricant is laminated on the outermost surface can be used.

  The shrink label of the present invention is attached to the container by a method of attaching to the container in the presence of water. For example, a shrink label having at least a heat-shrinkable film and a printed layer is cut into a long strip having a desired width, and is rounded into a cylindrical shape with the coating layer facing inward so that the main stretching direction is the circumferential direction. The sides are overlapped and bonded with a solvent, an adhesive, heat, or the like, and then cut into a desired length as necessary to form a cylindrical shrink label. As an example of a method for attaching a label to a container in the presence of water, a cylindrical shrink label formed by the above method is supplied to an automatic label attaching device, cut to a desired length as necessary, and then attached to the container body. Fits continuously, passes through a steam tunnel (heater) at a predetermined temperature (for example, 70 to 95 ° C.), and exhibits adhesiveness to the coating layer 4 with water (water vapor), and at the same time the heat-shrinkable film 2 is heat-shrinked. By doing so, a method of attaching the label in a state of being in close contact with the container can be mentioned.

  As another example of the method of attaching the label to the container in the presence of water, the cylindrical shrink label is fitted on the container body, and then immersed in a water bath at a predetermined temperature (for example, 70 to 95 ° C.). There is a method in which the label is in close contact with the container by causing the coating layer 4 to exhibit adhesiveness and simultaneously heat shrinking the heat shrinkable film 2. In addition, the filling time of the contents in the container may be any before and after the shrink wrapping.

  According to the said method, since the coating layer of a shrink label expresses adhesiveness with water, the heat-shrinkable label can contact | adhere to the container surface. It should be noted that the label and the container need only be in close contact with each other with a strength that can prevent idle rotation. Further, after use, the label can be easily peeled off without leaving glue on the surface of the container, and the container can be recycled.

  In the labeled container of the present invention, since the label and the container are in close contact with each other, it is possible to prevent the label from spinning around when the cap of the container is opened. For example, a bottle with a large torque required for opening and a bottle with a relatively small diameter of the bottle body, such as a bottle can with a cap diameter of 38 mm and a body diameter of 52 mm, and a laminate processing with a polyester film on the surface. It is possible to effectively prevent the shrink label from coming into close contact with the bottle that has been subjected to the slippery process.

  The labeled container of the present invention includes, for example, beverages such as beer, sake, wine, etc., juices, carbonated beverages, water, tea, etc .; seasonings such as soy sauce, mirin, mentsuyu, oil; liquid detergents, etc. Available as a container.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples.

Example 1
Acrylic resin as a thermoplastic resin [trade name “ARUFON UH-2140”, manufactured by Toagosei Co., Ltd .; glass transition temperature (Tg) 50 ° C., weight average molecular weight 14000, solid content 100%] 20 parts by weight, isopropyl After dissolving in a mixed solvent consisting of 30 parts by weight of alcohol and 40 parts by weight of ethyl acetate, hydroxypropylcellulose (HPC) as a water-soluble adhesive resin [trade name “HPC H”, manufactured by Nippon Soda Co., Ltd .; A coating agent was prepared by adding 10 parts by weight and stirring. The obtained coating agent had no abnormality in liquid state and was a uniform mixed solution.
A heat-shrinkable polystyrene film provided with a printing layer formed using acrylic ink (trade name “PS-985”, manufactured by Sakata Inks) on one side [thickness 60 μm: manufactured by Gunze, product name “GMNS”] The obtained coating agent was applied to the surface of the printing layer side by gravure printing so that the thickness was 2 μm to form a shrink label having a coating layer.

Example 2
In Example 1, the same operation as in Example 1 was performed except that the product name “HPC L” (powder) manufactured by Nippon Soda Co., Ltd. was used instead of “HPC H” manufactured by Nippon Soda Co., Ltd. Was prepared. The obtained coating agent had no abnormality in liquid state and was a uniform mixed solution.
A shrink label was formed by the same operation as in Example 1 using the obtained coating agent.

Example 3
In Example 1, the same operation as in Example 1 was performed except that the product name “HPC SSL” (powder) manufactured by Nippon Soda Co., Ltd. was used instead of “HPC H” manufactured by Nippon Soda Co., Ltd. Was prepared. The obtained coating agent had no abnormality in liquid state and was a uniform mixed solution.
A shrink label was formed by the same operation as in Example 1 using the obtained coating agent.

Example 4
In Example 1, as the water-soluble adhesive resin, the same operation as in Example 1 was performed except that ethyl cellulose (EC) [trade name “N-50”, manufactured by NN Chemical Co .; powdered] was used instead of HPC. A coating agent was prepared. The obtained coating agent had no abnormality in liquid state and was a uniform mixed solution.
A shrink label was formed by the same operation as in Example 1 using the obtained coating agent.

Example 5
In Example 1, the same operation as in Example 1 was performed except that PVA [trade name “JP-33”, manufactured by Nippon Vinegar Poval Co .; powder] was used instead of HPC as the water-soluble adhesive resin. A coating agent was prepared. The obtained coating agent had no abnormality in liquid state and was a uniform mixed solution.
A shrink label was formed by the same operation as in Example 1 using the obtained coating agent.

Comparative Example 1
Hydroxypropylcellulose (HPC) as a water-soluble adhesive resin [trade name “HPC SSL”, manufactured by Nippon Soda Co., Ltd .; powder] 20 parts by weight is added to a solvent composed of 80 parts by weight of isopropyl alcohol and 80 parts by weight of ethyl acetate. The coating agent was prepared by stirring and dissolving. The obtained coating agent had no abnormality in liquid state and was a uniform mixed solution.
A shrink label was formed by the same operation as in Example 1 using the obtained coating agent.

Example 6
Acrylic resin as a thermoplastic resin [trade name “ARUFON UH-2140”, manufactured by Toagosei Co., Ltd .; Tg 50 ° C., weight average molecular weight 14000, solid content 100%] 20 parts by weight, 30 parts by weight of isopropyl alcohol and acetic acid To a solution dissolved in a solvent consisting of 40 parts by weight of ethyl, 10 parts by weight of HPC [trade name “HPC L”, manufactured by Nippon Soda Co., Ltd .; powdered] as a water-soluble adhesive resin and 1 part by weight of a 70% strength by weight sorbitol aqueous solution. The coating agent was prepared by adding and stirring. The obtained coating agent had no abnormality in liquid state and was a uniform mixed solution.
A shrink label was formed by the same operation as in Example 1 using the obtained coating agent.

Example 7
In Example 6, the same operation as in Example 6 was performed except that ethyl cellulose (EC) [trade name “N-50”, manufactured by NN Chemical Co .; powdered] was used as the water-soluble adhesive resin instead of HPC. A coating agent was prepared. The obtained coating agent had no abnormality in liquid state and was a uniform mixed solution.
A shrink label was formed by the same operation as in Example 1 using the obtained coating agent.

Example 8
In Example 6, the same operation as in Example 6 was performed except that PVA [trade name “JP-33”, manufactured by Nippon Vinegar Poval Co .; powdered] was used instead of HPC as the water-soluble adhesive resin. A coating agent was prepared. The obtained coating agent had no abnormality in liquid state and was a uniform mixed solution.
A shrink label was formed by the same operation as in Example 1 using the obtained coating agent.

Comparative Example 2
Acrylic resin as a thermoplastic resin [trade name “ARUFON UH-2140” manufactured by Toagosei Co., Ltd .; Tg 50 ° C., weight average molecular weight 14000, solid content 100%] 30 parts by weight, 30 parts by weight of isopropyl alcohol and acetic acid A coating agent was prepared by adding to a solvent consisting of 40 parts by weight of ethyl and stirring to dissolve. The obtained coating agent had no abnormality in liquid state and was a uniform mixed solution.
A shrink label was formed by the same operation as in Example 1 using the obtained coating agent.

Example 9
Acrylic resin as a thermoplastic resin [trade name “LR-1941”, manufactured by Mitsubishi Rayon Co., Ltd .; Tg 110 ° C., weight average molecular weight 70000, solid content 30%] 50 parts by weight, 30 parts by weight of isopropyl alcohol and ethyl acetate A coating agent was prepared by adding 5 parts by weight of HPC [trade name “HPC L”, manufactured by Nippon Soda Co., Ltd .; powder] as a water-soluble adhesive resin to a solution dissolved in a solvent consisting of 15 parts by weight. . The obtained coating agent had no abnormality in liquid state and was a uniform mixed solution.
A shrink label was formed by the same operation as in Example 1 using the obtained coating agent.

Example 10
Urethane resin as a thermoplastic resin [trade name “Samprene IB 422”, manufactured by Sanyo Chemical Industries, Ltd .; Tg-40 ° C., weight average molecular weight 40000-50000, solid content 30%] 50 parts by weight of isopropyl alcohol 30 By adding and stirring 5 parts by weight of HPC [trade name “HPC L”, manufactured by Nippon Soda Co., Ltd .; powdered] as a water-soluble adhesive resin to a solution dissolved in a solvent consisting of 15 parts by weight of ethyl acetate and 15 parts by weight of ethyl acetate A coating agent was prepared. The obtained coating agent had no abnormality in liquid state and was a uniform mixed solution.
Heat-shrinkable polystyrene film with a printing layer formed using urethane-based ink (trade name “NT Hyramic”, manufactured by Dainichi Seika Co., Ltd.) on one side [thickness 60 μm: Gunze Co., Ltd., trade name “GMNS” The coating agent thus obtained was applied to the surface of the printed layer side by gravure printing to a thickness of 2 μm to form a shrink label having a coating layer.

Example 11
10 parts by weight of vinyl chloride-vinyl acetate copolymer resin as a thermoplastic resin [trade name “TAO”, manufactured by Nissin Chemical Industry Co., Ltd .; Tg 77 ° C., weight average molecular weight 15000, solid content 100%] By adding 5 parts by weight of HPC [trade name “HPC L”, manufactured by Nippon Soda Co., Ltd .; powdered] as a water-soluble adhesive resin to a solution dissolved in a solvent composed of parts by weight and 30 parts by weight of ethyl acetate, and stirring. A coating agent was prepared. The obtained coating agent had no abnormality in liquid state and was a uniform mixed solution.
A shrink label was formed by the same operation as in Example 1 using the obtained coating agent.

Example 12
Cellulose resin as a thermoplastic resin [trade name “CAB-381-0.5”, manufactured by Eastman Chemical Co .; Tg 130 ° C., weight average molecular weight 30000, solid content 100%] 15 parts by weight, isopropyl alcohol 50 parts by weight A coating agent obtained by adding 5 parts by weight of HPC [trade name “HPC L”, manufactured by Nippon Soda Co., Ltd .; powdered] as a water-soluble adhesive resin to a solution dissolved in a solvent consisting of 30 parts by weight of ethyl acetate. Was prepared. The obtained coating agent had no abnormality in liquid state and was a uniform mixed solution.
A shrink label was formed by the same operation as in Example 1 using the obtained coating agent.

Example 13
In Example 1, a coating agent was prepared in the same manner as in Example 1 except that 2 parts by weight of the water-soluble adhesive resin was used. The obtained coating agent had no abnormality in liquid state and was a uniform mixed solution.
A shrink label was formed by the same operation as in Example 1 using the obtained coating agent.

Example 14
A coating agent was prepared in the same manner as in Example 1 except that 1 part by weight of the water-soluble adhesive resin was used in Example 1. The obtained coating agent had no abnormality in liquid state and was a uniform mixed solution.
A shrink label was formed by the same operation as in Example 1 using the obtained coating agent.

Example 15
In Example 1, a coating agent was prepared in the same manner as in Example 1 except that 0.2 part by weight of the water-soluble adhesive resin was used. The obtained coating agent had no abnormality in liquid state and was a uniform mixed solution.
A shrink label was formed by the same operation as in Example 1 using the obtained coating agent.

Evaluation test Preventing idle rotation Shrink labels obtained in Examples and Comparative Examples are rolled into a cylindrical shape so that the main stretching direction of the base film is the circumferential direction, and both ends are bonded with a solvent, and a long cylindrical shrink label A continuum was obtained. This shrink label continuous body is supplied to an automatic label mounting apparatus, cut into each label, and then externally fitted into a cylindrical bottle can with a cap of 190 ml capacity (cap diameter: 38 mm, body diameter: 52 mm, manufactured by Toyo Seikan) Then, it was immersed in a water bath at 95 ° C. and thermally contracted. After the 20 containers with labels thus obtained were dried by leaving them at room temperature for 1 day, when the bottle was opened, “○” indicates that no empty rotation occurred between the label and the bottle, and “X” indicates that empty rotation occurred. As evaluated. These results are shown in Table 1.

  The shrink labels obtained in the examples are excellent in preventing idling, and in particular, Examples 1 to 9 and 13 to 15 (both acrylic resins) in which both the thermoplastic resin and the printing layer are composed of the same resin. In addition, the shrink label of Example 10 (both urethane resin) exhibited an extremely high idling prevention effect. On the other hand, in Comparative Example 1 in which the coating agent is composed only of a water-soluble adhesive resin, the coating agent is dissolved in water when immersed in a water bath, and the adhesion strength to the container is remarkably reduced, thereby preventing idle rotation. It was inferior. The label of Comparative Example 2 using only the thermoplastic resin did not adhere to the container and was easy to idle.

It is a schematic sectional drawing which shows an example of the shrink label of this invention.

Explanation of symbols

1 Label 2 Heat-shrinkable film 3 Printed layer 4 Coating layer

Claims (4)

A shrink label in which a printing layer and a coating layer are laminated in this order on at least one surface of a heat-shrinkable film, and the coating layer includes a water-soluble adhesive resin capable of expressing adhesiveness in the presence of water, and an acrylic type It is formed with a coating agent containing at least one thermoplastic resin selected from resin, urethane resin, vinyl chloride-vinyl acetate copolymer resin and cellulose resin, and is provided on the outermost surface of the label. The printing layer contains a binder resin selected from an acrylic resin, a urethane resin, a vinyl chloride-vinyl acetate copolymer resin, and a cellulose resin, and the thermoplastic resin in the coating layer and the printing layer (1) Combination of acrylic resin and acrylic resin (regardless of left and right order) (2) Combination of urethane resin and urethane resin, (3) Combination of vinyl chloride-vinyl acetate copolymer resin and vinyl chloride-vinyl acetate copolymer resin, (4) Cellulose resin and cellulose resin (5) A combination of a vinyl chloride-vinyl acetate copolymer resin and an acrylic resin, and (6) a combination of a cellulose resin and an acrylic resin. The shrink label according to claim 1, wherein a ratio of the water-soluble adhesive resin and the thermoplastic resin in the coating layer is the former / the latter (weight ratio) = 0.1 / 99.9 to 50/50. The shrink label according to claim 1 or 2, wherein the coating layer further contains a sugar alcohol or a derivative thereof. A labeled container in which the shrink label according to any one of claims 1 to 3 is attached to a cylindrical container.

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