KR20110126876A - A film label having easy feel off property in the high temperature water - Google Patents

Abstract

PURPOSE: A film label is provided to maintain adhesive force for fixed time at cold stored state or room temperature and to be easily separated from a container by easily losing the adhesive force by hot water. CONSTITUTION: A film label comprises a base film of synthetic resin material having a printing layer and an adhesion layer which is formed in the base file with one body. The adhesive consisting of the adhesion layer has hot water disappearing property which loses adhesive force by hot water. The film label maintains the adhesive force for a fixed time at cold stored state or room temperature. The film label is easily separated from a container by losing the adhesive force by the hot water.

Description

Film label with easy separation property in high temperature water {A FILM LABEL HAVING EASY FEEL OFF PROPERTY IN THE HIGH TEMPERATURE WATER}

The present invention relates to a film label having an easy separation property in hot water, in particular, hot water separated from the container by easily losing the adhesion in hot water while maintaining the adhesion for a certain time in ordinary distribution, cold storage and normal temperature water The present invention relates to a film label having easy separation characteristics.

At present, many labels are adhered to beautiful labels for the purpose of advertisement, design aesthetics, etc. These labels have been developed and used in various ways according to various industrial purposes.

In general, the label is automatically attached to the container by using an automatic labeling machine to transfer the adhesive label with pressure-sensitive adhesive from the release tape of the label tape to the surface of the container. Generally, the label tape has a thickness of 25 to 250 in which the label shape is printed. A label sheet having a thickness of about μm is temporarily attached to the release paper via the pressure-sensitive adhesive layer and then produced by cutting only the label sheet in the form of a label.

The label is usually fixed on the product by a pressure sensitive adhesive in the case of thermoplastic films (eg polyolefins such as biaxially oriented polypropylene-BOPP) and by an adhesive dispersed in an aqueous medium in the case of paper. do. The latter is often referred to as wet adhesive labels, but is also referred to as low temperature adhesives or just adhesive labels.

Various materials have been developed for the purpose of the label and the pressure-sensitive adhesive.

Competition in alcoholic beverage markets such as beer, wine, or spirits is intensifying, so breweries have been looking for ways to capture lovers and get them to buy their products. Packaging is a major part of promotions, especially when sold in supermarkets, and for manufacturers, the drive for differentiation is fierce.

The 'non-label' look has become fashionable in the pressure-sensitive adhesive (PS) market many years ago, and retailers have found many benefits from this new form of shelf appeal. This is accomplished by applying a clear transparent label (or colored transparent label to match the color of the product) to the product. Alternatively or additionally, the opposite side of the transparent or clear label (ie, the "inside" side attached to the product) may be completely or partially coated (eg, printed or metallized), such that the coating or print By not being located outside of, it can be better protected from abrasion and tearing (friction, action of solvent, etc.).

However, in the wet adhesive labeling process, there are various disadvantages when using conventional transparent plastic films (OPP, polyester-PE, polyethylene phthalate-PET), which are generally used in the PS market, as substrates for making transparent wet adhesive labels. This happens. Such thermoplastic films differ from the paper labels used in conventional wet adhesive machines. For example, thermoplastic films have a high moisture barrier (they are not semipermeable to water), which results in a longer time for the wet glue to dry (the label is held in place), which is a high speed labeling line. However, this can be a disadvantage when accurate positioning of the label is required. Thus, thermoplastic films are not an ideal substitute for paper labels in conventional production line setups for attaching wet adhesive labels to products such as bottles. In addition, aqueous coatings are inappropriate and do not adhere well to thermoplastic films, which often become hydrophobic without further surface treatment.

The substrate commonly used to make wet adhesive labels is opaque paper. Although thermoplastic films are transparent, the above mentioned disadvantages of thermoplastic films and wet adhesive coatings have made it necessary to use pressure sensitive adhesives to produce products with non-labeled looks with satisfactory performance. Thus, manufacturers who generally use labeling equipment for wet adhesive paper labels have faced significant capital expenditures and confusion that require them to be replaced with equipment suitable for pressure sensitive labels if they follow a non-label look. Certain waterborne adhesive systems have been developed for use in labels.

WO97 / 00298 (Henkel) describes an adhesive system for adhering an entire plastic label onto a plastic body. The adhesive system uses pickup glue and redundant glue. The pickup glue is characterized by having sufficient wet adhesion in the wet state but not adhering to one or more substrates in the dry state. The pickup glue is 5 to 85% by weight of one or more water soluble polymers, 0 to 1.0% by weight of one or more antifoams, and 0 to 1.0 weight, based on casein, starch, dextrin, glucose, polyvinyl alcohol, polyurethane or polyacrylic acid It contains one or more preservatives in%, the remaining percentage is occupied by water.

US Pat. Nos. 4,464,202 and 4,462,838 (both Henkel) describe aqueous adhesive compositions useful for labeling bottles. More specifically, these inventions are based on starch derivatives and have flow-controlling additives and, optionally, other conventional additives, such as: (a) at least one hydroxyalkyl ether of oxidized starch having an average degree of substitution (MS) of 0.2 Together with (b) a water-soluble cellulose derivative, a water-soluble synthetic polymer, casein and an aqueous adhesive for mechanical labeling with the content of at least one polymer dissolved in an aqueous phase, selected from the group consisting of water-soluble starch derivatives separate from component (a). It relates to a composition.

U.S. Patent 4,675,351 (Borden Inc.) describes adhesive formulations useful for adhering paper labels to glass bottles, the viscosity and flow of which are suitable for use in modern labeling equipment and are immersion resistant for at least 72 hours in ice water. Has It is based on soy protein glass and does not use casein.

US Patent 5,455,066 (Henkel) describes a water soluble adhesive useful for labeling bottles. This adhesive is based on casein, water soluble extenders, natural or synthetic resinous acids, resin alcohols or resin esters and alcohols.

Other non-aqueous adhesive systems have been developed for use in polymer labels.

U.S. Patent 5,366,251 (Brandt) describes an acrylic acid coated clear label used to provide a water resistant label printed on the reverse side. Adhesive systems based on heat active solvents are used to adhere the film to products such as glass containers.

When applying this wet glue directly to a conventional OPP label film, it has been found that it takes several days to adhere without dry days. This inadequate performance makes wet glue unsuitable for direct use in non-hydrophobic OPP films. Attempts have been made to modify such hydrophobic plastic polymeric films to be suitable for use in fixing labels using wet adhesive adhesives. However, this technique is completely separate from what is required for the use of wet glue in biopolymerizable films.

WO 97/43744 (Nordenia) is a water soluble coating of which all or part of its adhesive surface is coated with an adhesive based on starch, cellulose, glucose or dextrin, or a dry layer of an adhesive made of polyvinyl acetate, or polyvinyl alcohol. An adhesive label composed of a layered plastic film is described. After drying, the adhesive layer can be removed from the outer surface of the container without residue.

WO 99/19412 to Process Resources Corp. (= US Pat. No. 6,306,242 (Dronzek)) describes a method of securing polypropylene labels to glass or rapid products using an adhesive based on water. Hydrophobic PP should be coated with a hydrophilic coating to produce a film suitable for wet glue. This method is unsuitable for the conventional equipment used for paper labels.

WO 01/56893 (Grafiche Record SRL) describes a method of fixing a polypropylene (PP) label to a product using an adhesive based on water (wet adhesive). Although this method is designed for use in conventional paper labeling equipment, the PP film is coated with an acrylic polymer, printed with an ink containing an oxidizing salt, and then with a film having a specific terpolymer therein to accommodate the wet glue. You have to overpaint. This is an expensive and complicated process.

Conventionally, due to the ease of labeling operation, a film of a stiff material such as polyethylene terephthalate (PET), polyvinyl chloride (PVC) or the like has been generally used as an adhesive label, and a film of a soft material such as polyethylene has not been used.

However, when films of stiffer materials such as polyethylene terephthalate or polyvinyl chloride are used in flexible containers, wrinkles and lifting are often formed because the physical properties of the film cannot match the flexibility of the containers. If wrinkles and lifting are formed, there is a problem that the shape of the label is deformed and the printed appearance is damaged.

In order to solve these problems, U.S. Patent No. 4,587,158 discloses adhesive labels of low density polyethylene films as labels for squeeze bottles, but generally adhesive labels tend to soften when printed. When the printing adhesive label of the low density polyethylene disclosed in the above-described patent specification is attached to a container having flexibility, such a printing label has a low tensile strength, and thus the label may be damaged due to the elongation of the container. In addition, since the label has a small rigidity, there is a problem in that the operation of the automatic labeling machine becomes difficult.

In the conventional transparent polyethylene film, when printing was performed, there was a problem in that the appearance as a label was inferior in view of low print sharpness.

In addition, since the label has to maintain adhesion in particular during normal distribution and cold storage, it is a rule to use a strong adhesive that does not easily lose adhesion when the adhesive for maintaining the adhesion to the container. The use of a pressure-sensitive adhesive having a strong adhesive force has a problem in that it is difficult to recycle a labeled container in terms of resource recycling in view of the recent trend of development of environmentally friendly products. Even if the beer bottle using the paper label reinforced in the conventional glass container is used, in order to recycle the recovered beer bottle, in principle, the beer bottle itself must be cleaned (washed) and disinfected as well as the label attached to the beer bottle must be removed. However, the label can be separated only by using a sodium hydroxide solution to remove the label, the use of sodium hydroxide solution is not preferable in terms of water pollution and increased water treatment costs.

In particular, when a conventional paper label is used in a polyethylene terephthalate (PET) container mainly used for soft drinks, there is a problem in reducing the recyclability of the container itself unless the paper label is completely separated. There is almost no development of the separation method or means, and PET containers with paper labels are almost impossible to recycle, and in the case of recycling, most of them are cumbersome and time-consuming separation process of manual paper label separation. Is required.

Therefore, there is a demand for the development of a film label having easy separation characteristics in hot water separated from a container by easily losing adhesion in high temperature water while maintaining adhesion for a certain time in ordinary distribution, cold storage, and room temperature water. .

The present invention was devised to solve the problems of the prior art as described above, it is easy in hot water separated from the container by easily losing the adhesion in hot water while maintaining the adhesion for a certain time in ordinary distribution, cold storage and room temperature water. It is an object to provide a film label having one separation property.

The film label having easy separation characteristics in the hot water according to the present invention comprises a base film made of a synthetic resin in which a printing layer is formed, and an adhesive layer formed integrally with the base film, and constitutes the pressure-sensitive adhesive layer. The pressure-sensitive adhesive is characterized in that made of a pressure-sensitive adhesive having a desorption characteristic in high temperature water in which the adhesive force is lost in the high temperature water.

The high temperature desorption characteristic of the pressure-sensitive adhesive layer may be a loss of adhesion in water at a temperature of 50 to 99 ℃, preferably 70 to 90 ℃.

The present invention has the effect of providing a film label having easy separation characteristics in hot water separated from the container by easily losing the adhesion in hot water while maintaining the adhesion for a certain time in ordinary distribution, cold storage and room temperature water.

Hereinafter, the present invention will be described in detail with reference to specific examples.

The film label having easy separation characteristics in the hot water according to the present invention comprises a base film made of a synthetic resin in which a printing layer is formed, and an adhesive layer formed integrally with the base film, and constitutes the pressure-sensitive adhesive layer. The pressure-sensitive adhesive is characterized in that made of a pressure-sensitive adhesive having a desorption characteristic in high temperature water in which the adhesive force is lost in the high temperature water.

In the above, the base film can be understood to be molded in the form of a synthetic resin commercially supplied by leading manufacturers at home and abroad, and such a synthetic resin is polyethylene (high density polyethylene, low density polyethylene), polypropylene, polyvinyl chloride ( Various synthetic resins known at home and abroad that can be molded into films including general purpose plastics such as PVC) and polystyrene can be used. The base film may itself be printable (characteristics suitable for printing) or may be made printable by surface treatment such as corona discharge or the like. The base film is known to those skilled in the art, and can also be printed to function as a label through a known printing method that can be easily carried out.

The pressure-sensitive adhesive layer does not easily fall out of the container during a typical distribution process, and has an adhesive force that does not drop out of the container within a certain time, preferably at least 72 hours, especially in cold storage and normal temperature water, and at the same time easily adheres in hot water. It can be used to have a desorption characteristic that is separated from the container by loss, and any pressure-sensitive adhesive having such desorption characteristics (hereinafter, referred to as 'hot water desorption characteristics') can be used, and the present invention provides a It is not limited by the kind, it can be understood that any one having the above-described high temperature water desorption characteristics can be used.

In particular, the high-temperature desorption characteristic may be that the adhesion is lost in water at a temperature of 50 to 99 ℃, preferably 70 to 90 ℃.

By the above configuration, at least in normal circulation, cold storage and normal temperature water, the adhesive force is maintained for a certain time to function as a label, and at the same time, soaked in hot water when washing bottles for recycling of containers after being consumed. The application of some physical force allows the base film to be easily separated from the container, thereby facilitating the bottle bottling of the container, thereby increasing the recycling yield of the container.

Particularly, according to the present invention, the film label having the characteristics as described above cannot be evaporated from the water on the opposite side of the label because the label itself is made of a film made of synthetic resin. It maintains adhesion for a long time to function as a label, and when labeling for recycling, the label can be easily removed from the container by simply immersing it in hot water, especially water at a temperature of 50 to 99 ° C., and taking it out with a light physical force. It is easy to wash and recycle, and it can replace paper labels to protect forest resources and save tributary resources, and it can be applied to PET bottles as well as glass bottles such as beer bottles. It has advantages such as facilitating the recycling of bottles.

In addition, it enables the separation of bottles and labels of containers without the use of toxic and corrosive substances such as sodium hydroxide, which is used for bottle washing of existing paper labels. .

The present invention can be applied to both a glass beer bottle and a soft drink container made of synthetic resin such as PET, and thus can be used in the production and distribution of these alcoholic beverages and beverages.

Although the present invention has been described in detail only with respect to the described embodiments, it will be apparent to those skilled in the art that various modifications and variations are possible within the technical scope of the present invention, and such modifications and modifications are within the scope of the appended claims.

Claims (2)

A pressure sensitive adhesive having a desorption characteristic in a high temperature water in which a base film made of a synthetic resin in which a printing layer is formed, and a pressure sensitive adhesive layer formed integrally with the base film, wherein the pressure sensitive adhesive constituting the pressure sensitive adhesive layer loses adhesion in high temperature water. Film label having easy separation characteristics in hot water, characterized in that consisting of.
The method of claim 1,
The hot water desorption characteristic of the pressure-sensitive adhesive layer is a film label having easy separation characteristics in high temperature water, characterized in that the adhesive force is lost in water at a temperature of 50 to 99 ℃, preferably 70 to 90 ℃.