KR102175675B1 - Toluene-free Ink Retention Label - Google Patents

Abstract

The present invention relates to a toluene-free retention label, including: an adhesive layer having a release layer on the top thereof so that it may be adhered to a container; a substrate layer formed on the bottom of the adhesive layer and including pulp; a metal layer formed on the bottom of the substrate layer; a printing layer formed on the bottom of the metal layer and printed by using an ink composition containing an alcohol-based solvent; and a protective coating layer formed on the bottom of the printing layer for protecting the surface of the retention label and dissolution into aqueous sodium chloride solution, wherein the protective coating layer includes a coating composition containing 10-40 wt% of a polyvinyl butyral resin, 1-20 wt% of a ketone resin, 0.01-1 wt% of an antistatic agent, 0.01-1 wt% of polyethylene wax and 40-80 wt% of an alcohol-based solvent. Therefore, the retention label is eco-friendly and minimizes generation of pollutants during the removal of the label, since it uses no toluene having a high cancer-causing possibility and harmfulness.

Description

Toluene-free Ink Retention Label {Toluene-free Ink Retention Label}

The present invention relates to a retention label that does not contain toluene, which is eco-friendly because toluene, which has high carcinogenic potential and harmfulness, is not used as a solvent and can minimize the occurrence of contaminants in the process of removing the label.

Containers such as plastic and glass containers are generally distributed on the market with a label indicating a trademark, expiration date, ingredients contained, precautions for use or usage, etc.

In preparing these labels, a large amount of toluene is used as a solvent. Toluene is a solvent containing an aromatic hydrocarbon, benzoyl, and its use is restricted industrially due to its high carcinogenic potential and harmfulness. In particular, in advanced countries emphasizing environmental aspects, restrictions on its use are becoming stronger. A significant part of the residual toluene used during label manufacturing is removed by a drying process during the manufacturing process, but a trace amount of toluene is not fundamentally removed, and there is room for some remaining on the label. Thus, if possible, blocking the use of toluene throughout the entire label manufacturing process may be the most useful way to alleviate toluene concerns.

In addition, the container with the label attached is recovered from the consumer as it is, and handed over to a recycling company. Typically, recyclers separate labels during reuse or recycling of recovered containers.

Conventionally, paper labels or heat-shrinkable film labels have been used, and the labels of containers recovered during regeneration are the solubility of sodium hydroxide aqueous solution in the state of heating an aqueous sodium hydroxide solution to a temperature of 80°C to 85°C and thermal contraction rate between the container and the label. It was removed using the difference.

However, in the process of dissolving the ink layer printed on the label, the ink layer contaminates the aqueous solution, and in particular, residual toluene used as a solvent is dissolved, and there is a problem that it is detected in the aqueous solution for cleaning. In addition, there is a problem in that the contaminants enter the container in which cleaning is performed and the cleaning efficiency is deteriorated, and the contaminants continue to remain in the aqueous solution for cleaning, and the aqueous solution must be frequently replaced.

Accordingly, there is a need to develop a label that does not use toluene as a solvent and can be easily separated from a container while preventing contamination by separation of the ink layer.

Korean Patent Registration No. 10-0369453 Korean Patent Registration No. 10-0511763 Korean Patent Registration No. 10-1798889

The present invention was conceived to solve the above-described problems, and an embodiment of the present invention is eco-friendly because toluene, which has high carcinogenic potential and harmfulness, is not used as a solvent, and when the label is removed with an aqueous sodium hydroxide solution, it is printed on the label. It is intended to provide a retention label that does not contain toluene that can minimize the occurrence of contaminants due to leaching of the ink layer.

Various problems to be solved by the present invention are not limited to the problems mentioned above, and other problems that are not mentioned will be clearly understood by those skilled in the art from the following description.

One embodiment of the present invention is a retention label that does not contain toluene, wherein the retention label includes an adhesive layer having a release layer formed on an upper surface thereof so as to be adhered to the container by interviewing; A base layer formed on the lower surface of the adhesive layer and comprising pulp; A metal layer formed on a lower surface of the base layer; A printing layer formed on a lower surface of the metal layer and printed using an ink composition containing an alcohol-based solvent; It is formed on the lower surface of the printing layer and includes a protective coating layer that protects the surface of the retention label and prevents elution into an aqueous sodium hydroxide solution; The protective coating layer contains 10 to 40% by weight of a polyvinyl butyral resin, 1 to 20% by weight of a ketone resin, 0.01 to 1% by weight of an antistatic agent, 0.01 to 1% by weight of polyethylene wax, and 40 to 80% by weight of an alcohol-based solvent. It provides a retention label comprising the coating composition.

The alcohol-based solvent contained in the printing layer and the protective coating layer is based on 100 parts by weight of one or more alcohol-based solvents selected from the group consisting of isopropyl alcohol (IPA), methanol (MOH), ethanol (EOH), and mixtures thereof. ; It may be one further comprising 30 to 90 parts by weight of at least one selected from the group consisting of ethyl acetate, N-propyl acetate, and mixtures thereof.

The printing layer is a pigment 1 to 40% by weight, alcohol-soluble polyamide 18 to 30% by weight, nitrocellulose 0.1 to 3% by weight, antistatic agent 0.01 to 1% by weight, polyethylene wax 0.01 to 1% by weight, and alcohol-based solvent 40 to It is printed using an ink composition containing 80% by weight; The alcohol-soluble polyamide has a softening point of 90 to 100°C, a viscosity of 10 to 20 Pas at 180°C to 240°C, an acid value of less than 5 mg KOH/g, and an amine value of 1 to 5 mg KOH/g. It can be used that the amount of ingredients is selected.

The ink composition may further include 0.01 to 1% by weight of a hydrogenated-terpene resin and 0.01 to 1% by weight of hydroxybutyrylic acid.

The polyvinyl butyral resin has a glass transition temperature of 70 to 90°C; A weight average molecular weight of 10,000 to 70,000 g/mol; A mixture of 80,000 to 120,000 g/mol in a weight ratio of 1: 1 to 3 may be used.

According to the retention label that does not contain toluene according to an embodiment of the present invention, by using an alcohol-based solvent as a solvent, toluene having high carcinogenic potential and harmfulness is not used, so there is an environmentally friendly effect.

In addition, when the label is removed with an aqueous sodium hydroxide solution, there is an effect that the peeling of the label occurs very cleanly within a short time. That is, there is an effect of minimizing the occurrence of contaminants due to leaching of the ink layer printed on the label. Accordingly, it is possible to extend the replacement cycle of the aqueous sodium hydroxide solution for removing the label, and reduce the recycling cost of the recycling container, thereby increasing the recycling rate of the recycling container.

1 is a perspective view of a glass container to which a trademark-printed retention label is adhered.
2 is a schematic cross-sectional view of a retention label according to an embodiment of the present invention.
3 to 5 show graphs of GC/MS analysis results of retention labels prepared according to Examples 1 to 3, respectively.
6 is an image showing a state of an aqueous sodium hydroxide solution over time when the retention labels prepared according to Example 3 and Comparative Example 1 are immersed in an aqueous sodium hydroxide solution.
7 is an image showing a state of an aqueous sodium hydroxide solution over time when a glass container with a retention label manufactured according to Example 3 and Comparative Example 1 is immersed in an aqueous sodium hydroxide solution.

Hereinafter, embodiments of the present invention will be described in detail. However, this is presented as an example, and the present invention is not limited thereby, and the present invention is only defined by the scope of the claims to be described later.

One embodiment of the present invention is a retention label that does not contain toluene, wherein the retention label includes an adhesive layer having a release layer formed on an upper surface thereof so as to be adhered to the container by interviewing; A base layer formed on the lower surface of the adhesive layer and comprising pulp; A metal layer formed on a lower surface of the base layer; A printing layer formed on a lower surface of the metal layer and printed using an ink composition containing an alcohol-based solvent; It is formed on the lower surface of the printing layer and includes a protective coating layer that protects the surface of the retention label and prevents elution into an aqueous sodium hydroxide solution; The protective coating layer contains 10 to 40% by weight of a polyvinyl butyral resin, 1 to 20% by weight of a ketone resin, 0.01 to 1% by weight of an antistatic agent, 0.01 to 1% by weight of polyethylene wax, and 40 to 80% by weight of an alcohol-based solvent. It provides a retention label comprising the coating composition.

According to the retention label that does not contain toluene according to an embodiment of the present invention, by using an alcohol-based solvent as a solvent, toluene having high carcinogenic potential and harmfulness is not used, so there is an environmentally friendly effect.

In addition, when the label is removed with an aqueous sodium hydroxide solution, there is an effect that the peeling of the label occurs very cleanly within a short time. That is, there is an effect of minimizing the occurrence of contaminants due to leaching of the ink layer printed on the label. Accordingly, it is possible to extend the replacement cycle of the aqueous sodium hydroxide solution for removing the label, and reduce the recycling cost of the recycling container, thereby increasing the recycling rate of the recycling container.

1 shows a perspective view of a glass container to which a retention label is adhered according to an embodiment of the present invention.

More specifically, the alcohol-based solvent included in the printing layer and the protective coating layer is preferably at least one alcohol-based solvent selected from the group consisting of isopropyl alcohol (IPA), methanol (MOH), ethanol (EOH), and mixtures thereof. Can be used. At this time, the alcohol-based solvent may further improve the above effect by using a mixture of 90 to 99% by weight of isopropyl alcohol (IPA) and 1 to 10% by weight of ethanol (EOH).

In addition, the alcohol-based solvent included in the printing layer and the protective coating layer is one or more alcohol-based solvents selected from the group consisting of isopropyl alcohol (IPA), methanol (MOH), ethanol (EOH), and mixtures thereof. Per part by weight; Ethyl acetate (ethyl acetate), N-propyl acetate (N-propyl acetate), and one or more selected from the group consisting of a mixture thereof, 30 to 90 parts by weight further containing one, the above effect can be further improved. In addition, there is an effect of further improving the integrity of the retention label including the adhesive layer, the base layer, the metal layer, and the printing layer.

The retention label 100 according to an embodiment of the present invention includes an adhesive layer 101 having a release layer 110 formed on the upper surface thereof so that it can be adhered by an interview with the container 10; A base layer 102 formed on the lower surface of the adhesive layer and comprising pulp; A metal layer 103 formed on the lower surface of the base layer; A printing layer 104 formed on the lower surface of the metal layer and printed using an ink composition containing an alcohol-based solvent; It may be formed on the lower surface of the printing layer to include a protective coating layer 105 that protects the surface of the retention label and prevents elution into an aqueous sodium hydroxide solution. A schematic cross-sectional view of a retention label according to an embodiment of the present invention is shown in FIG. 2.

First, the adhesive layer 101 is formed by forming a release layer 110 on the upper surface so that it can be bonded by interviewing a plastic or glass container. The adhesive composition that can be included in the adhesive layer is generally used in the art, and the type is not particularly limited.

However, as a non-limiting example of the adhesive composition, 0.1 to 5 weight of alumina hollow beads whose surface is modified with silica and 3-chloropropyl trimethoxy silane having an average particle diameter of 1 to 10 nm per 100 parts by weight of an acrylic resin Parts, and 10 to 30 parts by weight of an alcohol-based solvent, further improving the adhesive strength with the substrate layer and the container, and removing the label with an aqueous sodium hydroxide solution so that the peeling of the label occurs very cleanly within a short time. It can be further improved.

In this case, the acrylic resin may be an acrylate monomer or an acrylate oligomer. At this time, as the acrylate monomer, 1,2-ethylene glycol diacrylate, 1,12-dodetandiol acrylate, 1,4-butanediol di(meth)acrylate, and 1,6-hexanediol di(meth) Acrylate, neopentyl glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, neopentyl glycol adipate (neopentylglycol adipate) di (meth) acrylate, hydroxyl puivalic acid neopentyl glycol Di(meth)acrylate, dicyclopentanyl (dicyclopentanyl) di(meth)acrylate, caprolactone-modified dicyclopentenyl di(meth)acrylate, ethylene oxide-modified di(meth)acrylate, di(meth)acrylic Roxyethyl isocyanurate, allylated cyclohexyl di(meth)acrylate, tricyclodecanedimethanol (meth)acrylate, dimethylol dicyclopentane di(meth)acrylate, ethylene oxide-modified hexahydro Phthalic acid di(meth)acrylate, tricyclodecane dimethanol (meth)acrylate, neopentyl glycol modified trimethylpropane di(meth)acrylate, adamantane di(meth)acrylate or 9,9-bis Bifunctional acrylates such as [4-(2-acryloyloxyethoxy)phenyl]fluorene; Trimethylolpropane tri(meth)acrylate, dipentaerythritol tri(meth)acrylate, propionic acid-modified dipentaerythritol tri(meth)acrylate, pentaerythritol tri(meth)acrylate, propylene oxide Trifunctional acrylates such as modified trimethylolpropane tri(meth)acrylate, trifunctional urethane (meth)acrylate, or tris(meth)acryloxyethyl isocyanurate; Tetrafunctional acrylates such as diglycerin tetra(meth)acrylate or pentaerythritol tetra(meth)acrylate; 5-functional acrylates, such as propionic acid-modified dipentaerythritol penta (meth)acrylate; And dipentaerythritol hexa(meth)acrylate, caprolactone-modified dipentaerythritol hexa(meth)acrylate or urethane (meth)acrylate (ex. isocyanate monomer and a reactant of trimethylolpropane tri(meth)acrylate 6-functional acrylates such as, but are not limited thereto In addition, urethane acrylate oligomers, epoxy acrylate oligomers, ester acrylate oligomers, cardo-based acrylate oligomers, etc. may be used as the acrylate oligomer. Here, the urethane acrylate oligomer is formed by polymerization of an isocyanate-based monomer and a polyol, and the isocyanate-based compound includes at least one selected from aliphatic isocyanate-based compounds, aromatic isocyanate-based compounds, and combinations thereof, and polyol In addition, the epoxy acrylate may be a (meth)acrylic acid hydroxyalkyl ester compound, wherein the epoxy acrylate is bisphenol A diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, and (meth)acrylic acid of phenol novolac epoxy resin. In addition, the ester acrylate may include a polyfunctional polyester acrylate compound of a polyhydric alcohol, and the cardo acrylate may include at least one selected from adducts and combinations thereof. It may be a compound to which an acrylate obtained by reacting at least one selected from the group consisting of a cardo-based compound, a dianhydride compound, a diol compound, diacrylic acid, and combinations thereof.

In addition, silica and 3-chloropropyl trimethoxy silane having an average particle diameter of 1 to 10 nm are mixed in a weight ratio of 1: 0.1 to 0.5, thereby further improving the adhesive strength with the substrate layer and the container. The effect can be further improved.

In addition, the alumina hollow beads can further improve the effect that the label peeling occurs very cleanly within a short time when the label is removed with an aqueous sodium hydroxide solution.

The alumina hollow beads can be manufactured by a manufacturing method generally used in the art, and the manufacturing method is not particularly limited. However, as a non-limiting example of the method for producing the alumina hollow beads, the steps of dispersion polymerization of an aromatic vinyl compound or an unsaturated carboxylic acid ester compound as a monomer to prepare polymer fine particles; Preparing a polymer-alumina composite particle coated with alumina on the surface of the prepared polymer particle; And the polymer-alumina composite particles are heat-treated to remove the polymer to prepare an alumina hollow bead. It may be preferably used that is prepared by a manufacturing method comprising. At this time, the monomer is generally used in the art, and the kind thereof is not particularly limited. For example, the aromatic vinyl compound is styrene, α-methylstyrene, α-chlorostyrene, p-tert-butylstyrene, p -Any one selected from methylstyrene, p-chlorostyrene, o-chlorostyrene, 2,5-dichlorostyrene, 3,4-dichlorostyrene, dimethylstyrene and divinylbenzene may be more preferably used; The unsaturated carboxylic acid ester compound is more than any one selected from methyl acrylate, methyl meth acrylate, ethyl acrylate, ethyl meth acrylate, propyl acrylate, propyl meth acrylate, butyl acrylate and butyl methacrylate It can be used preferably. In addition, the heat treatment is preferably performed in a nitrogen atmosphere at a temperature of 300 to 400 °C.

In addition, the alcohol-based solvent may be preferably the same as described for the alcohol-based solvent contained in the printing layer and the protective coating layer.

Meanwhile, the base layer 102 may be formed on a lower surface of the adhesive layer 101 and may include pulp.

The base layer including the pulp further includes 1 to 50 parts by weight of a silk fibroin hydrolyzate powder and 1 to 50 parts by weight of a polyamidoamine-epichlorohydrin resin, based on 100 parts by weight of the pulp, and the strength of the base layer itself And there is an effect of improving the water resistance, and then, the formation of the metal layer formed on the lower surface of the base layer can be formed more easily and with excellent adhesion.

The silk fibroin hydrolyzate powder is sericin by washing the selected cocoon with Marseilles soap at a concentration of 0.3 to 0.7% by weight and an aqueous solution containing sodium carbonate at a concentration of 0.1 to 0.5% by weight at 100 to 120°C for 0.5 to 2 hours. Preparing silk fibroin from which the oil has been removed; Acid hydrolysis by washing the silk fibroin from which sericin has been removed with distilled water and dissolving it in 3 to 8N hydrochloric acid for 5 to 7 hours; Adding sodium hydroxide to stop the acid hydrolysis; And obtaining a silk fibroin hydrolyzate having a molecular weight of 0.01 to 10000 kDa by removing residual salts using an electrodialysis system (Acilyzer-02, Astom, Tokyo, Japan). Can be used.

Meanwhile, the metal layer 103 is formed on the lower surface of the base layer 102. This metal layer has a property of being removed by reacting with an alkaline aqueous solution. That is, this metal layer serves to easily separate the label from the container when the label is removed with an aqueous sodium hydroxide solution. More specifically, in order to regenerate the labeled container, the container is immersed in an aqueous sodium hydroxide solution heated to a temperature of 80°C to 85°C. At this time, the metal layer in the label reacts with the aqueous sodium hydroxide solution to ionize the container. The adhesion of the label to the container rapidly weakens, so that the label is easily separated from the container.

The metal layer may preferably include aluminum. That is, the aluminum contained in the metal layer causes the following chemical reaction with an aqueous sodium hydroxide solution heated to a temperature of 80° C. to 85° C., so that the label is easily separated from the container. That is, aluminum is converted to [Al(OH) ₄ ] ^- , dissolved in water, and hydrogen is produced as a by-product.

2Al(s) + 2NaOH(aq) + 6H ₂ O → 2Na ⁺ (aq) + 2[Al(OH) ₄ ] ^- (aq) + 3H ₂ (g)

In addition, the thickness of the metal layer may be 150Å to 30㎛. When the thickness of the metal layer is within the above range, a label that is separated from the container in a short time can be obtained at a relatively low manufacturing cost. In addition, the metal layer may be formed by chemical vapor deposition (CVD), coating, or printing, but is not limited thereto.

Meanwhile, the printing layer 104 is formed on the lower surface of the metal layer 103 and may be printed using an ink composition including an alcohol-based solvent.

More specifically, the printing layer is a pigment 1 to 40% by weight, alcohol-soluble polyamide 18 to 30% by weight, nitrocellulose 0.1 to 3% by weight, antistatic agent 0.01 to 1% by weight, polyethylene wax 0.01 to 1% by weight and alcohol By printing using an ink composition containing 40 to 80% by weight of the solvent, when the label is removed with an aqueous sodium hydroxide solution, peeling of the label occurs very cleanly within a short time. That is, there is an effect of minimizing the occurrence of contaminants due to leaching of the ink layer printed on the label. Accordingly, it is possible to extend the replacement cycle of the aqueous sodium hydroxide solution for removing the label, and reduce the recycling cost of the recycling container, thereby increasing the recycling rate of the recycling container.

At this time, the alcohol-soluble polyamide has a softening point of 90 to 100°C, a viscosity of 10 to 20 Pas at 180°C to 240°C, an acid value of less than 5 mg KOH/g, and an amine value of 1 to 5 mg KOH/g. By using a product whose amount of amine component is selected so as to have, it is well soluble in alcohol-based solvents so that desired phrases or pictures can be clearly printed on the retention label, and it is not well soluble in sodium hydroxide aqueous solution, so the ink layer printed on the label Can effectively prevent leaching.

In addition, the ink composition further comprises 0.01 to 1% by weight of a hydrogenated-terpene resin and 0.01 to 1% by weight of hydroxybutyrylic acid, as well as the adhesive layer, the base layer, and the metal layer, as well as the protective coating layer formed afterwards. The integrity of the label can be further improved, so that when the label is removed with an aqueous sodium hydroxide solution, the above-described layers are not separated, dissolved and eluted, and the entire label is produced very cleanly at once and within a short time.

On the other hand, the protective coating layer 105 is formed on the lower surface of the printing layer 104 to protect the surface of the retention label and prevent elution into an aqueous sodium hydroxide solution.

More specifically, the protective coating layer is polyvinyl butyral resin 10 to 40% by weight, ketone resin 1 to 20% by weight, antistatic agent 0.01 to 1% by weight, polyethylene wax 0.01 to 1% by weight, and alcohol-based solvent 40 to 80% by weight Including a coating composition containing, as well as protecting the surface of the retention label from external contamination and physical impact, when peeling the label with an aqueous sodium hydroxide solution, included in the adhesive layer, the base layer, the metal layer and the printing layer It functions to protect the retention label so that the ingredients do not dissolve. In particular, it is possible to very effectively prevent the pulp contained in the substrate layer from dissolving in the form of porridge, or the ink composition contained in the printing layer being eluted and contaminating the sodium hydroxide aqueous solution hazy.

The polyvinyl butyral resin has a glass transition temperature of 70 to 90°C; A weight average molecular weight of 10,000 to 70,000 g/mol; When using a mixture of 80,000 to 120,000 g/mol in a weight ratio of 1: 1 to 3, the coating composition penetrates to the substrate layer, the metal layer and the printing layer, thereby further improving the integrity of the label, thereby making the label When removing with an aqueous sodium hydroxide solution, the above-described layers are not separated, dissolved or eluted, and the entire label is produced very cleanly at once and within a short time.

In addition, the ketone resin, together with the polyvinyl butyral resin, functions to protect the surface of the retention label from external contamination and physical impact. In this case, the polyvinyl butyral resin and the ketone resin are mixed in a weight ratio of 2: 1 to further improve the above effect.

On the other hand, the aqueous sodium hydroxide solution for removing the retention label according to the embodiment of the present invention may preferably be used by heating an aqueous solution having a concentration of 1 to 5% by weight at a temperature of 80 ℃ to 85 ℃.

According to the retention label that does not contain toluene according to an embodiment of the present invention, by using an alcohol-based solvent as a solvent, toluene having high carcinogenic potential and harmfulness is not used, so there is an environmentally friendly effect.

In addition, when the label is removed with an aqueous sodium hydroxide solution, there is an effect that the peeling of the label occurs very cleanly within a short time. That is, there is an effect of minimizing the occurrence of contaminants due to leaching of the ink layer printed on the label. Accordingly, it is possible to extend the replacement cycle of the aqueous sodium hydroxide solution for removing the label, and reduce the recycling cost of the recycling container, thereby increasing the recycling rate of the recycling container.

Above, the preferred embodiment of the present invention has been described in detail, but the present invention is not limited to the above embodiment, and various modifications by those of ordinary skill in the relevant field within the scope of the technical idea of the present invention This is possible.

<Example 1>

A retention label having the configuration of FIG. 2 was prepared in the following manner.

Adhesive layer (101)

Alumina hollow beads with surface modified by mixing silica and 3-chloropropyl trimethoxy silane having an average particle diameter of about 5.3 nm in a weight ratio of 1: 0.2 based on 100 parts by weight of 1,2-ethylene glycol diacrylate It was coated using an adhesive composition containing 3 parts by weight and 25 parts by weight of a solvent. At this time, the solvent is based on 100 parts by weight of an alcohol-based solvent of isopropyl alcohol (IPA) and ethanol (EOH) (92: 8 weight ratio); A mixture of 55 parts by weight of ethyl acetate was used.

Base layer (102)

A material containing 19 parts by weight of a silk fibroin hydrolyzate powder and 13 parts by weight of a polyamidoamine-epichlorohydrin resin was used based on 100 parts by weight of the pulp.

Metal layer (103)

An aluminum metal layer having a thickness of about 315 Å was used.

Printed layer(104)

Pigment 24% by weight, alcohol-soluble polyamide 22% by weight, nitrocellulose 3% by weight, antistatic agent 0.5% by weight, polyethylene wax 0.5% by weight, hydrogenated-terpene resin 0.5% by weight and hydroxybutyrylic acid 0.5% by weight and solvent 49% by weight Printed using an ink composition containing %. At this time, the solvent is based on 100 parts by weight of an alcohol-based solvent of isopropyl alcohol (IPA) and ethanol (EOH) (92: 8 weight ratio); A mixture of 55 parts by weight of ethyl acetate was used.

At this time, the alcohol-soluble polyamide has a softening point of 95°C, a viscosity of 11 Pas at 180°C, an acid value of 5 mg KOH/g, and an amine value of 3 mg KOH/g. I did.

Protective coating layer (105)

The protective coating layer was coated using a coating composition containing 34 wt% polyvinyl butyral resin, 17 wt% ketone resin, 0.5 wt% antistatic agent, 0.5 wt% polyethylene wax, and 48 wt% solvent. At this time, the solvent is based on 100 parts by weight of an alcohol-based solvent of isopropyl alcohol (IPA) and ethanol (EOH) (92: 8 weight ratio); A mixture of 55 parts by weight of ethyl acetate was used.

In this case, the polyvinyl butyral resin has a glass transition temperature of 82°C; Having a weight average molecular weight of 17,300 g/mol; A mixture of 109,100 g/mol in a weight ratio of 1: 2 was used.

<Example 2>

Conducted in the same manner as in Example 1, but based on 100 parts by weight of isopropyl alcohol (IPA) as a solvent used in the adhesive layer 101, the printing layer 104, and the protective coating layer 105 of Example 1; The mixture of 80 parts by weight of ethyl acetate was different.

<Example 3>

It was carried out in the same manner as in Example 1, but isopropyl alcohol (IPA) and ethanol (EOH) 92 as solvents used in the adhesive layer 101, the printing layer 104, and the protective coating layer 105 of Example 1. 8 weight ratio) of 100 parts by weight of an alcohol-based solvent; The mixture of 40 parts by weight of ethyl acetate was different.

<Comparative Example 1>

It was carried out in the same manner as in Example 1, except that toluene was used as a solvent used in the adhesive layer 101, the printing layer 104, and the protective coating layer 105 of Example 1 above.

<Test Example>

Gas Chromatography-Mass Spectrometry (GC-MS)

For the retention labels prepared in Examples 1 to 3, gas chromatography-mass spectrometry (GC-MS) was performed to confirm the type of volatile solvent remaining on the retention labels, and the results are shown in FIGS. It is shown in 5.

As can be seen in FIGS. 3 to 5, it was confirmed that toluene having high carcinogenic potential and high toxicity was not detected in the retention labels prepared in Examples 1 to 3 of the present invention.

Observation of dissolution of the label and dissolution of the ink layer when the label is immersed in aqueous sodium hydroxide solution

After heating a 4% by weight aqueous sodium hydroxide solution to a temperature of about 80° C., the retention labels prepared in Example 3 and Comparative Example 1 were added thereto, and whether or not the label was dissolved and the ink layer was The elution was observed, and the results are shown in FIG. 6.

As can be seen in FIG. 6, in contrast to the retention label prepared in Comparative Example 1, the retention label prepared in Example 3 of the present invention exhibited a color change or pulp of sodium hydroxide aqueous solution according to the elution of the ink composition. It was confirmed that generation of suspended solids due to the dissolution of the containing substrate layer hardly occurred.

That is, the retention label manufactured in the embodiment of the present invention can minimize the occurrence of contaminants in the process of removing the label, so that the replacement cycle of the sodium hydroxide aqueous solution for removing the label can be extended, and the recycling container can be recycled. By reducing the cost, the effect of increasing the recycling rate of the recycling container is expected.

Observation of label peeling rate and ink layer elution when removing label from container with aqueous sodium hydroxide solution

After heating a 4% by weight aqueous sodium hydroxide solution to a temperature of about 80° C., a glass container with a retention label prepared in Example 3 and Comparative Example 1 was added thereto, and the label was peeled off with time. / Observation of dissolution and dissolution of the ink layer, and the results are shown in FIG. 7.

As can be seen in FIG. 7, in contrast to the retention label prepared in Comparative Example 1, the retention label prepared in Example 3 of the present invention exhibited a color change or pulp of the sodium hydroxide aqueous solution according to the elution of the ink composition. It was confirmed that generation of suspended solids due to the dissolution of the containing substrate layer hardly occurred. In addition, it was confirmed that the retention label prepared in Example 3 of the present invention had a faster peeling rate of the label from the container compared to the retention label prepared in Comparative Example 1.

That is, the retention label prepared in the embodiment of the present invention can minimize the occurrence of contaminants in the process of removing the label because peeling of the label is very clean within a short time, thus reducing the replacement cycle of the sodium hydroxide aqueous solution for removing the label. It can be extended, and by reducing the recycling cost of the recycling container, an effect of increasing the recycling rate of the recycling container is expected.

As described above, those skilled in the art to which the present invention pertains will understand that the present invention can be implemented in other specific forms without changing the technical spirit or essential features. Therefore, all the embodiments described above are illustrative and should be understood as non-limiting. The scope of the present invention should be construed as including all altered or modified forms derived from the meaning and scope of the claims to be described later rather than the above detailed description, and equivalent concepts thereof.

10: Courage
100: retention label
110: release layer 101: adhesive layer
102: base layer 103: metal layer
104: printing layer 105: protective coating layer

Claims (5)

As a retention label that does not contain toluene,
The retention label includes an adhesive layer having a release layer formed on an upper surface thereof so as to be adhered to the container by an interview; A base layer formed on the lower surface of the adhesive layer and comprising pulp; A metal layer formed on a lower surface of the base layer; A printing layer formed on a lower surface of the metal layer and printed using an ink composition containing an alcohol-based solvent; It is formed on the lower surface of the printing layer and includes a protective coating layer that protects the surface of the retention label and prevents elution into an aqueous sodium hydroxide solution;
The protective coating layer contains 10 to 40% by weight of a polyvinyl butyral resin, 1 to 20% by weight of a ketone resin, 0.01 to 1% by weight of an antistatic agent, 0.01 to 1% by weight of polyethylene wax, and 40 to 80% by weight of an alcohol-based solvent. Retention label comprising a coating composition.
The method of claim 1,
Alcohol-based solvent contained in the printing layer and the protective coating layer
Based on 100 parts by weight of at least one alcohol-based solvent selected from the group consisting of isopropyl alcohol (IPA), methanol (MOH), ethanol (EOH), and mixtures thereof;
Retention label, characterized in that it further comprises 30 to 90 parts by weight of at least one selected from the group consisting of ethyl acetate, N-propyl acetate, and mixtures thereof.
The method of claim 1,
The printing layer is a pigment 1 to 40% by weight, alcohol-soluble polyamide 18 to 30% by weight, nitrocellulose 0.1 to 3% by weight, antistatic agent 0.01 to 1% by weight, polyethylene wax 0.01 to 1% by weight, and alcohol-based solvent 40 to It is printed using an ink composition containing 80% by weight;
The alcohol-soluble polyamide has a softening point of 90 to 100°C, a viscosity of 10 to 20 Pas at 180°C to 240°C, an acid value of less than 5 mg KOH/g, and an amine value of 1 to 5 mg KOH/g. Retention label, characterized in that the amount of ingredients are selected.
The method of claim 3,
The ink composition is a retention label, characterized in that it further comprises 0.01 to 1% by weight of a hydrogenated-terpene resin and 0.01 to 1% by weight of hydroxybutyrylic acid.
The method of claim 1,
The polyvinyl butyral resin has a glass transition temperature of 70 to 90°C;
A weight average molecular weight of 10,000 to 70,000 g/mol; Retention label, characterized in that the mixture of 80,000 to 120,000 g / mol 1: 1 to 3 weight ratio.

Images