KR20240055534A - Coating layer with excellent eco-friendly properties and peeling properties - Google Patents

Abstract

Disclosed is a coating layer that has excellent eco-friendly properties and peeling properties and can be recycled.
In the coating layer adhered on a substrate according to the present invention, the primer layer is disposed on the substrate and includes a first PVC resin, a plasticizer, a surface control agent, and a pigment; an undercoat layer disposed on the primer layer and including a second PVC resin and a maleic acid-modified rosin resin; and a top coat layer disposed on the undercoat layer and including an acrylate oligomer, an acrylate monomer, and a photoinitiator, wherein the first PVC resin includes a PVC homopolymer and a PVC copolymer, and the PVC copolymer It may include a compound represented by the following formula (1).
[Formula 1]

Each of m and n is an integer from 1 to 100.

Description

Coating layer with excellent eco-friendly properties and peeling properties {COATING LAYER WITH EXCELLENT ECO-FRIENDLY PROPERTIES AND PEELING PROPERTIES}

The present invention relates to a coating layer that has excellent eco-friendly properties and peeling properties and can be recycled.

Package design is a coating layer that protects a product. It is a design that utilizes visual design and text to effectively convey information about product features and contents and encourage consumers to purchase.

However, as the rapid economic growth of the industrialization and information age encouraged mass production and excessive competition between brands, excessive packaging and one-time packaging have rapidly increased.

As a result, environmental problems such as environmental pollution, global warming, and ecosystem destruction have emerged, and the importance of sustainable package design is rising.

As environmental issues emerge globally, the importance of eco-friendly packages is increasing in the design field. Additionally, Korea's Ministry of Environment strengthened regulations on cosmetic packaging materials in the second half of last year.

In response to these changes, the cosmetics industry is utilizing sustainable package design. However, domestic sustainable package design remains at an inadequate level.

Therefore, to solve environmental problems, it is necessary to study eco-friendly and recyclable package design.

The purpose of the present invention is to provide a coating layer with excellent eco-friendly properties and peeling properties.

Another object of the present invention is to provide a recyclable coating layer.

The objects of the present invention are not limited to the objects mentioned above, and other objects and advantages of the present invention that are not mentioned can be understood by the following description and will be more clearly understood by the examples of the present invention. Additionally, it will be readily apparent that the objects and advantages of the present invention can be realized by the means and combinations thereof indicated in the patent claims.

In the coating layer adhered on a substrate according to the present invention, the primer layer is disposed on the substrate and includes a first PVC resin, a plasticizer, a surface control agent, and a pigment; an undercoat layer disposed on the primer layer and including a second PVC resin and a maleic acid-modified rosin resin; and a top coat layer disposed on the undercoat layer and including an acrylate oligomer, an acrylate monomer, and a photoinitiator, wherein the first PVC resin includes a PVC homopolymer and a PVC copolymer, and the PVC copolymer It may include a compound represented by the following formula (1).

[Formula 1]

Each of m and n is an integer from 1 to 100.

The degree of polymerization (DP) of the PVC homopolymer may be 700 to 1300, and the weight average molecular weight may be 20 to 200.

The glass transition temperature (Tg) of the PVC homopolymer may be 40 to 100°C.

The surface control agent may include polyether-modified polydimethylsiloxane represented by the following formula (2).

[Formula 2]

Each of m, n, x, and y is an integer from 1 to 100.

Each of R and R ² is -H or -CH ₃ .

The maleic acid modified rosin resin may include a compound represented by the following formula (3).

[Formula 3]

The maleic acid-modified rosin resin may have a softening point of 110 to 130°C and an acid value of 30 to 50 mg KOH/g.

A primer layer containing 90 to 110 parts by weight of a plasticizer, 1 to 10 parts by weight of a surface conditioner, and 1 to 5 parts by weight of a pigment, based on 100 parts by weight of the first PVC resin; An undercoat layer containing 80 to 100 parts by weight of maleic acid-modified rosin resin, based on 100 parts by weight of the second PVC resin; and a top coat layer containing 80 to 90 parts by weight of acrylate monomer and 1 to 10 parts by weight of a photoinitiator, based on 100 parts by weight of acrylate oligomer.

The coating layer according to the present invention has excellent eco-friendly properties and peeling properties, making it recyclable.

In addition to the above-described effects, specific effects of the present invention are described below while explaining specific details for carrying out the invention.

Figure 1 is a photograph of the coating layer of the present invention peeled off after attachment.

The above-described objects, features, and advantages will be described in detail later with reference to the attached drawings, so that those skilled in the art will be able to easily implement the technical idea of the present invention. In describing the present invention, if it is determined that a detailed description of known technologies related to the present invention may unnecessarily obscure the gist of the present invention, the detailed description will be omitted. Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the attached drawings. In the drawings, identical reference numerals are used to indicate identical or similar components.

Hereinafter, the “top (or bottom)” of a component or the arrangement of any component on the “top (or bottom)” of a component means that any component is placed in contact with the top (or bottom) of the component. Additionally, it may mean that other components may be interposed between the component and any component disposed on (or under) the component.

Additionally, when a component is described as being “connected,” “coupled,” or “connected” to another component, the components may be directly connected or connected to each other, but the other component is “interposed” between each component. It should be understood that “or, each component may be “connected,” “combined,” or “connected” through other components.

Below, an induction heating and wireless power transmission device according to some embodiments of the present invention will be described.

Existing coating layers have the disadvantage of being mostly discarded or reused through a complex recycling process as they do not have peeling properties.

However, the eco-friendly coating layer of the present invention has the same or greater visual effect and text application as compared to the conventional coating layer, and has excellent physical peeling properties.

The eco-friendly coating layer of the present invention is attached to a substrate, and various materials such as glass, wood, metal, and plastic can be used as the substrate without limitation.

In the coating layer adhered on a substrate according to the present invention, the coating layer is disposed on the substrate, a primer layer comprising a first PVC resin, a plasticizer, a surface control agent and a pigment, a primer layer, and a second PVC resin and It includes an undercoat layer containing a maleic acid-modified rosin resin, and a top coat layer disposed on the undercoat layer and containing an acrylate oligomer, an acrylate monomer, and a photoinitiator.

The primer layer is a cured product of the primer composition, and the primer composition may include a first PVC resin, a plasticizer, a surface control agent, a pigment, and an organic solvent. When the composition is cured, the organic solvent evaporates and disappears, and only the first PVC resin, plasticizer, surface conditioner, and pigment are present in the primer layer.

The first PVC resin included in the primer layer may include PVC homopolymer and PVC copolymer. The mixing ratio of PVC homopolymer and PVC copolymer may be in a weight ratio of 1:1 to 1:10, but is not limited thereto.

The PVC copolymer may include a compound represented by the following formula (1).

[Formula 1]

Each of m and n is an integer from 1 to 100.

The degree of polymerization (DP) of PVC homopolymer may be 700 to 1300, preferably 700 to 1000. When the degree of polymerization of PVC homopolymer is 1000 or less, it is easy to control the viscosity of the solution during the synthesis process, and spray workability is excellent when coating.

If the degree of polymerization of PVC homopolymer is less than 700, peelability is poor. Conversely, if the degree of polymerization of PVC homopolymer exceeds 1300, it is difficult to control the viscosity of the synthetic solution and spray workability is deteriorated.

The weight average molecular weight of PVC homopolymer may be 20 to 200, preferably 40 to 150.

The glass transition temperature (Tg) of PVC homopolymer may be 40 to 100°C, preferably 60 to 90°C, and more preferably 70 to 85°C.

The primer layer may contain other ingredients based on 100 parts by weight of the first PVC resin.

Plasticizers may include one or more of fatty acid-based (Aliphates), trimellitates-based (Trimellitates), polyester-based (Polyester), epoxy-based (Epoxy), phosphate-based (Phosphates), and glycol-based (Glycol). For example, the plasticizer may include DEHCH (Diethyl hexyl cyclohexane).

Based on 100 parts by weight of the first PVC resin, it may contain 90 to 110 parts by weight of the plasticizer, preferably 95 to 100 parts by weight.

The surface control agent may include polyether-modified polydimethylsiloxane represented by the following formula (2).

[Formula 2]

Each of m, n, x, and y is an integer from 1 to 100.

Each of R and R ² may be -H or -CH ₃ .

Based on 100 parts by weight of the first PVC resin, it may contain 1 to 10 parts by weight of the surface conditioner, preferably 2 to 8 parts by weight.

The pigment may include a phthalocyanine-based organic pigment, and one or more colors may be selected from a variety of colors.

Based on 100 parts by weight of the first PVC resin, it may contain 1 to 5 parts by weight of pigment, preferably 2 to 3 parts by weight.

Organic solvents can be selected from a variety of types, such as ketone-based, acetate-based, ether-based, and alcohol-based.

Based on 100 parts by weight of the first PVC resin, it may contain 80 to 120 parts by weight of the organic solvent, preferably 90 to 110 parts by weight. If the content of the organic solvent exceeds 120 parts by weight, there is a problem that the compatibility and workability of the coating composition deteriorates.

The undercoat layer is a cured product of the undercoat composition, and the undercoat composition may include a second PVC resin, a maleic acid-modified rosin resin, and an organic solvent. When the composition is cured, the organic solvent evaporates and disappears, and only the second PVC resin and the maleic acid-modified rosin resin remain in the undercoat layer. And the undercoat layer may further include additives and pigments.

The second PVC resin can be used without limitation as long as it is a general PVC resin.

When the second PVC resin and the maleic acid-modified rosin resin are mixed, the adhesion to the primer layer is further increased.

The undercoating layer may contain other components based on 100 parts by weight of the second PVC resin.

The maleic acid modified rosin resin may include a compound represented by the following formula (3).

[Formula 3]

The softening point of the maleic acid modified rosin resin may be 110 to 130°C, preferably 120 to 125°C.

The acid value of the maleic acid modified rosin resin may be 30 to 50 mg KOH/g, preferably 35 to 45 mg KOH/g.

Based on 100 parts by weight of the second PVC resin, it may contain 80 to 100 parts by weight, and preferably 90 to 100 parts by weight, of the maleic acid modified rosin resin.

Organic solvents include toluene, xylene, aromatic hydrocarbon solvents such as Kocosol #100 (Kocosol #100, K-100, SK Energy Co., Ltd.), Cocosol #150 (Kocosol #150, K-150, SK Energy Co., Ltd.), and methyl. One of ketone solvents such as ethyl ketone, methyl propyl ketone, methyl butyl ketone, and ethyl propyl ketone, and ester solvents such as methyl acetate, ethyl acetate, n-propyl acetate, n-butyl acetate, and ethyl ethoxypropionate. It may include more.

It may contain 80 to 100 parts by weight of the organic solvent, preferably 90 to 100 parts by weight, based on 100 parts by weight of the second PVC resin.

When the content of the organic solvent satisfies 80 to 100 parts by weight, workability is improved and excellent physical properties of the paint film and coating layer can be exhibited.

The additive may include one or more of an antifoaming agent, a leveling agent, a dispersing agent, an ultraviolet absorber, a light stabilizer, a desiccant, a moisture absorbent, and a coupling agent, within the range that does not harm the inherent properties of the base layer.

The antifoam agent plays a role in improving the appearance characteristics of the paint film by suppressing bubbles generated during painting. The defoamer may include a silicone-based or non-silicone-based defoamer, and a polysiloxane type defoamer may be used.

The leveling agent is used to improve the appearance characteristics of the coating film while improving adhesion within the composition by leveling the base coat layer so that it is coated evenly and smoothly. The leveling agent may include one or more of acrylic, silicone, polyester, and amine leveling agents.

The dispersing agent serves to disperse each material constituting the composition and prevent re-agglomeration by maintaining a distance to ensure uniform physical properties of the coating film. The dispersant may be a high molecular weight block copolymer type dispersant.

The ultraviolet absorber may include a hydroxyphenyl triazine derivative having ultraviolet absorbing properties. The light stabilizer may include an amine-based light stabilizer, for example, a hindered amine light stabilizer (HALS).

It may contain 1 to 5 parts by weight of additives, preferably 2 to 3 parts by weight, based on 100 parts by weight of the second PVC resin.

Pigments can be used to express a desired color (color) or to increase the strength or gloss of the coating film, within the range that does not harm the inherent characteristics of the undercoat layer. As such pigments, organic pigments, inorganic pigments, metallic pigments, aluminum-paste, pearl, extender pigments, etc. can be used without limitation. For example, pigments may include red, yellow/orange, blue, black, white, pearl, and metallic pigments.

Based on 100 parts by weight of the second PVC resin, it may contain 1 to 5 parts by weight of pigment, and preferably 2 to 3 parts by weight.

When the pigment content is 1 to 5 parts by weight, the appearance characteristics and mechanical properties of the coating film can be improved without deterioration of dispersibility and storage stability.

The top coat layer is a cured product of the top coat composition, and the top coat composition may include an acrylate oligomer, an acrylate monomer, a photoinitiator, and an organic solvent. When the composition is cured, the organic solvent evaporates and disappears, and only acrylate oligomer, acrylate monomer, and photoinitiator exist in the top coat layer. And the top coat layer may further include additives.

Acrylate oligomers include non-yellowing aliphatic urethane acrylate oligomers with two functional groups, non-yellowing aliphatic urethane acrylate oligomers with three functional groups, non-yellowing aliphatic urethane acrylate oligomers with six functional groups, and non-yellowing aliphatic urethane acrylate oligomers with more than six functional groups. It may contain one or more types of non-yellowing aliphatic urethane acrylate oligomers. The functional group of urethane acrylate oligomer refers to a double bond. When this oligomer is irradiated with ultraviolet rays, it participates in a polymerization reaction initiated by a photoinitiator and hardens into a coating layer.

Examples of reactive acrylate monomers that can be used in ultraviolet curable paint compositions include isobonyl acrylate (IBOA), isobonyl methacrylate (IBOMA), tetrahydrofuryl acrylate (THFA), 2-phenoxyethyl acrylate, tripropyleneglycol diacrylate (TPGDA), 1,6-hexanediol diacrylate (HDDA), trimethylolpropane Triacrylate (trimethylolpropane triacrylate, TMPTA), pentaerythritol triacrylate (PETA), an acrylic monomer represented by the following formula (1), etc.

Considering the adhesion of the coating layer, solvent resistance, processability, scratch resistance, curing time, price of the coating composition, etc., it is preferable to mix them appropriately.

Based on 100 parts by weight of acrylate oligomer, it may contain 80 to 90 parts by weight of acrylate monomer.

The photoinitiator is a polymerization initiator activated by ultraviolet rays. The photoinitiator may include one or more of a benzophenone-based compound, a benzoin-based compound, a benzoin ether-based compound, a benzyl ketal-based compound, an acetophenone-based compound, an anthraquinone-based compound, and a thioxoxanthone-based compound. Specific examples of photoinitiators include Irgacure 184, 651, 819 (trade name of CIBA GEIGY, Switzerland), Micure MP-8 (trade name of Miwon Corporation, Korea), and Benzophenone.

It may contain 1 to 10 parts by weight of a photoinitiator, preferably 2 to 5 parts by weight, based on 100 parts by weight of acrylate oligomer.

The organic solvent may include one or more of methyl ethyl ketone, acetone, ethanol, propanol, butanol, ethyl acetate, butyl acetate, benzene, toluene, and xylene.

Based on 100 parts by weight of acrylate oligomer, it may contain 80 to 110 parts by weight of organic solvent, preferably 90 to 100 parts by weight.

Additives may include one or more types of defoamer, leveling agent, dispersant, and slip agent.

These may include one or more types, taking into account adhesion of the coating film, solvent resistance, impact resistance, processability, scratch resistance, curing time, price of the coating composition, etc.

It may contain 1 to 5 parts by weight of additives, preferably 1 to 2 parts by weight, based on 100 parts by weight of acrylate oligomer.

Each of the primer composition, undercoat composition, and topcoat composition that constitute the coating layer of the present invention can be prepared by mixing the components at 25 ± 5°C.

The coating layer of the present invention can form a primer layer, an undercoat layer, and a top coat layer, respectively, using spray coating on a substrate.

The primer composition can be spray coated and then dried at 60 to 80°C for 10 to 30 minutes to form a primer layer.

After spray coating the undercoat composition, the undercoat layer can be formed by drying at 50 to 70°C for 5 to 10 minutes.

The top coat composition can be spray coated and then dried at IR 50 to 70°C/1 to 3 minutes and UV irradiation at 800 to 1000 mJ/cm ² to form a top coat layer.

Figure 1 is a photograph of the coating layer of the present invention peeled off after attachment.

Referring to Figure 1, various colors and appearances can be displayed by attaching a coating layer to glass, metal materials, etc. And since the primer layer among the coating layers has excellent peeling properties, it can be confirmed that the physical peeling of the coating layer from the substrate is excellent, making it possible to recycle.

Specific examples of the coating layer with excellent eco-friendly properties and peeling properties are as follows.

1. Preparation of coating layer

The composition ratio of each layer was mixed as shown in Table 1 at room temperature, and a coating layer was prepared by spray coating and drying.

In Table 1, the composition ratio of the primer layer is expressed based on 100 parts by weight of PVC, which is a mixture of PVC homopolymer and PVC copolymer.

- Spray workability was checked by spraying the composition at a distance of 30cm from the glass substrate, drying it, and visually checking whether it was applied evenly. When drying, the primer layer was performed at 70°C for 20 minutes, the undercoat layer was performed at 60°C for 5 minutes, and the top coat layer was performed at IR 60°C and UV 800 mJ/cm ² for 3 minutes.

If there were no bubbles and no irregularities on the surface, it was marked as “excellent”; if there were any bubbles or irregularities on the surface, it was marked as “poor.”

- Peeling properties were expressed as “excellent” if there was no residue or adhesive on the surface of the substrate when the coating layer was peeled from the substrate at room temperature, and “poor” if there was residue or adhesive on the surface of the substrate.

[Table 1]

[Table 2]

[Table 3]

Referring to the results in Table 1, it can be seen that both the spray workability and peeling properties are excellent as the composition ratio and properties of the primer layer, base coat layer, and top coat layer are all satisfied.

On the other hand, if any of the degree of polymerization, weight average molecular weight, or glass transition temperature of PVC in the primer layer is not satisfied, if the content is out of range, or if the softening point or acid value of the rosin resin in the undercoat layer is not satisfied, the content of rosin resin must be adjusted. In case of deviation, spray workability and peeling characteristics were found to be poor.

As described above, the present invention has been described with reference to the illustrative drawings, but the present invention is not limited to the embodiments and drawings disclosed herein, and various modifications may be made by those skilled in the art within the scope of the technical idea of the present invention. It is obvious that transformation can occur. In addition, although the operational effects according to the configuration of the present invention were not explicitly described and explained while explaining the embodiments of the present invention above, it is natural that the predictable effects due to the configuration should also be recognized.

Claims (7)

In the coating layer adhered to the substrate,
a primer layer disposed on the substrate and comprising a first PVC resin, a plasticizer, a surface control agent, and a pigment;
an undercoat layer disposed on the primer layer and including a second PVC resin and a maleic acid-modified rosin resin; and
It is disposed on the undercoat layer and includes a top coat layer containing an acrylate oligomer, an acrylate monomer, and a photoinitiator,
The first PVC resin includes PVC homopolymer and PVC copolymer,
The PVC copolymer is a coating layer containing a compound represented by the following formula (1).
[Formula 1]

Each of m and n is an integer from 1 to 100.
According to paragraph 1,
The degree of polymerization (DP) of the PVC homopolymer is 700 to 1300,
A coating layer with a weight average molecular weight of 20 to 200.
According to paragraph 1,
A coating layer where the glass transition temperature (Tg) of the PVC homopolymer is 40 to 100°C.
According to paragraph 1,
The surface control agent is a coating layer comprising polyether-modified polydimethylsiloxane represented by the following formula (2).
[Formula 2]

Each of m, n, x, and y is an integer from 1 to 100,
Each of R and R ² is -H or -CH ₃ .
According to paragraph 1,
The maleic acid-modified rosin resin is a coating layer containing a compound represented by the following formula (3).
[Formula 3]

According to paragraph 1,
The softening point of the maleic acid modified rosin resin is 110 to 130°C,
A coating layer with an acid value of 30 to 50 mg KOH/g.
According to paragraph 1,
A primer layer containing 90 to 110 parts by weight of a plasticizer, 1 to 10 parts by weight of a surface conditioner, and 1 to 5 parts by weight of a pigment, based on 100 parts by weight of the first PVC resin;
An undercoat layer containing 80 to 100 parts by weight of maleic acid-modified rosin resin, based on 100 parts by weight of the second PVC resin; and
A coating layer comprising a top coat layer containing 80 to 90 parts by weight of acrylate monomer and 1 to 10 parts by weight of a photoinitiator, based on 100 parts by weight of acrylate oligomer.