KR101771112B1 - Coating composition comprising eco-friendly polyurethan resin, and coating film - Google Patents

Abstract

The present invention relates to an eco-friendly polyurethane resin, a production method thereof, and a coating composition containing the same. According to the present invention, provided is a water-dispersible polyurethane resin which exhibits excellent printing properties such as attachability, anti-blocking properties, and water resistance, and is also eco-friendly without containing harmful substances. Moreover, provided are a coating composition containing the same, and a coating film.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating composition containing an environmentally friendly polyurethane resin,

And a coating film comprising the environmentally friendly polyurethane resin.

Electrostatic printing processes include forming an image on a photoconductive surface to print an image on a substrate surface, combining the image using ink having charged particles back onto the surface, and transferring the charged particles to an image surface in the form of an image . The charged particles used in this case are generally referred to as "toner", which is provided in powder or liquid form.

In order to achieve stable print quality and high resolution image printing, various conditions must be met. Among them, the relationship between the surface of the substrate and the ink of "toner" is the most important factor directly affecting the print quality.

One of the most basic elements of the stable print quality that the base film should have is adhesion between the ink and the substrate surface. In particular, unlike a direct coating type printing method such as gravure printing, it is possible to maintain a stable printing quality by forming an image formed by applying an electric field and excellent adhesion force due to electrostatic printing characteristics. In order to realize the above physical properties, a water-dispersible resin having a carboxyl functional group added to a polyolefin resin is used as a coating material. According to US patent US 7470736, the concept of using ethylene acrylic acid dispersion as Michem®Prime 4990R.E available from Michelman is described. However, the polyethylene acrylic acid resin used for preparing the ethylene acrylic acid dispersion is a resin sold under the trademark Primaco (R) 5980I by Dow-Chemical, which can be prepared by dissolving the resin in an aqueous alkaline solution while maintaining an appropriate solid content and viscosity.

Secondly, one of essential physical properties to be provided as a base film is to maintain good adhesion to olefin-based films (PET, PE, PP, PO film, etc.) mainly used as a base film. Usually, the water-dispersed polyurethane resin is used for imparting adhesion force with the base film in order to impart the above-mentioned adhesion property. According to U.S. Patent No. 7470736, NeoRez® R-600 supplied by NeoResins Co., Ltd., Industrial Copolymer Ltd., for the purpose of increasing the adhesion to the above-mentioned concept of ethylene acrylic acid dispersion. Incorez 217 or Scott Bader Company Ltd. Such as TD 7037 or TD 7038, supplied by Nippon Polyurethane Industry Co., Ltd. However, since the water-dispersed polyurethane resin uses a high-volatility toxic substance such as DMF or NMP when synthesizing the urethane resin before water dispersion, the water-dispersed urethane resin also contains the same component. The coating composition containing the toxic substance may be classified as a toxic substance even with a very small amount of the coating composition itself, thereby threatening the safety of the operator in the production process.

The high-volatility toxic organic solvent is difficult to completely volatilize during the low-temperature drying process at a temperature of 130 ° C or less, and causes problems such as deterioration of the film property when the film is left on the film and blocking during winding. In addition, There is a problem to follow. In addition, a high calorie energy is required to dry all the high-boiling organic solvents. Excessive use of energy not only increases the production cost but also causes a problem in that a film having relatively low glass transition temperature (PE, PP, PO Etc.) to the user.

As in the case of the polyolefin resin to which the carboxyl functional group is imparted, the water-dispersed polyurethane also corresponds to a material to be dispersed in water by neutralization with an alkali salt such as ammonia or amine. In the synthesis method, a carboxyl functional group polymerized by radical polymerization The water-dispersed polyurethane synthesized by the hydroxy-isocyanate addition reaction with respect to the polyolefin-based resin imparted has a remarkably low weight-average molecular weight. For this reason, the polyolefin-based resin to which the carboxyl functional group is imparted can be utilized only up to 75% of the acid value contained in the resin during the neutralization of the alkali salt due to its high molecular weight. In addition, as the amount of the alkali salt is increased to increase the neutralization ratio, The viscosity tends to increase gradually in the water, so that it is generally used in a partially neutralized state. The inherent properties of the polyolefin-based resin to which the carboxyl functional group is imparted as described above are important characteristics to be considered when mixing with a water-dispersible resin using an alkaline salt having a relatively low molecular weight. When mixed with a resin, that is, an aqueous dispersion polyurethane resin or the like, the alkali salt contained in the water-dispersed polyurethane resin toward the polyolefin-based resin to which the carboxyl functional group is imparted is relatively neutralized relative to the fully neutralized water- As a result, the water-dispersed polyurethane resin gradually loses the alkali salt, and as a result, the dispersion stability of the water-dispersed polyurethane resin is disrupted And the behavior of the entire dispersed phase becomes gelled. There is a point.

Third, there is no blocking property between the films due to the physical properties to be provided as the base film. If the blocking characteristics between films are manifested, they will cause serious defects in the printing process as well as in the film processing, resulting in loss of value as a product. Particularly, the polyolefin resin having carboxyl functional groups used for securing the print quality has inherently low glass transition temperature, which makes it difficult to solve the blocking characteristic.

Korea Publication No. 10-2002-0060250 A (Released on July 16, 2002)

Disclosed is an environmentally-friendly water-dispersible polyurethane resin having excellent electrostatic printing characteristics, safety and toxicity, and a method for producing the same.

Another object of the present invention is to provide an eco-friendly coating composition and a coating film containing the environmentally-water-dispersible polyurethane resin, which can minimize the occurrence of blocking even when there is no toxic residual organic solvent in the coating film.

It is another object of the present invention to provide a coating composition and a coating film which minimize the occurrence of blocking and ensure storage stability by utilizing a third water-dispersible resin as a buffer composition together with the environmentally-friendly water-dispersible polyurethane resin according to the present invention do.

The eco-friendly polyurethane resin according to the present invention,

(a) a dialcohol monomer having hydroxy functional groups at both terminals;

(b) a dialcohol monomer having a carboxyl group functional group and hydroxy functional groups at both terminals; And

(c) diisocyanate monomers having isocyanate functional groups at both terminals; Lt; RTI ID = 0.0 >

And is an environment-friendly polyurethane resin.

The eco-friendly polyurethane resin according to the present invention is characterized by being a compound represented by the following formula (3).

(3)

or

In the formula, R ₆ is to be represented by the following formula, the terminal group R ₅ is an alkyl group having 3 to 20 carbon atoms, connected group R ₅ is an alkyl group having 3 to 20 carbon atoms, n is an integer from 1 to 20;

[Chemical Formula]

Wherein X is an amine group having an alkyl group having 1 to 20 carbon atoms, R ₁ , R ₂ and R ₄ are each independently an alkylene group having 6 to 20 carbon atoms, R ₃ is an alkylene group having 2 to 20 carbon atoms, k, l and m are each 1, and n is an integer of 1 to 100.

Further, the process for producing an environmentally friendly polyurethane resin according to the present invention comprises

(a) a diol monomer having hydroxy functional groups at both terminals, (b) a diol monomer having a carboxyl group functional group and hydroxy functional groups at both terminals, and (c) a diisocyanate monomer having isocyanate functional groups at both terminals, Producing a combination;

(D) neutralizing the carboxyl group functional group of the prepared copolymer with a tertiary amine which is not an accident-prone substance having non-toxicity, and dispersing it in water; And

Reacting the water-dispersed copolymer with (d) an alkyldiamine-based monomer having non-toxicity as a chain extender; And a control unit.

In addition, the coating composition according to the present invention,

(Ii) a water-dispersed polyolefin-based carboxyl (meth) acrylate copolymer resin, and (iii) a water-dispersed polyacrylate copolymer resin having a glass transition temperature of 50 to 120 ° C. .

Further, the coating film according to the present invention

A base film layer; And a coating layer formed by coating and thermosetting the coating composition according to the present invention on the upper or both sides of the base film layer; Is a laminated coating film.

According to the present invention, it is possible to provide an environmentally-friendly water-dispersible polyurethane resin which is excellent in printing properties such as adherence, anti-blocking property and water resistance, as well as toxic substances, a coating composition containing the same, and a coating film.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are further described in the text. It should be understood, however, that the invention is not intended to be limited to the particular forms disclosed, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the term "comprises" or "having" is intended to specify that there is a combination of features, numbers, steps, , Components, and the like, unless specifically excluded from the scope of the invention.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

The term 'coating' as used in the present invention means that a functional layer capable of imparting physical properties such as printability, substrate adhesion and anti-blocking property to various substrate surfaces using resin, paper, nonwoven fabric, cloth or composite material it means. In some cases, it may be used in the same sense as the protective layer.

1. Eco-friendly Water dispersion  Polyurethane resin

The method for producing the environmentally-friendly water-dispersed polyurethane resin according to the present invention will be described in more detail as follows.

First, as a first step, a 2L glass reactor is prepared so as to be free of moisture, and a diol monomer having hydroxy functional groups at both terminals and (c) a diisocyanate monomer having isocyanate functional groups at both terminals are reacted with a monomer (B) a diol monomer having a carboxyl group functional group and a hydroxyl functional group at both terminals (for example, the following formula: ???????? (DMPA) dissolved in dimethyl carbonate (DMC) at a concentration of about 20% by weight is slowly added to the reaction mixture for 30 minutes.

The molar ratio of (a) the diol monomer to be used for the reaction is 10 to 40 mol%, (b) the molar ratio of the carboxyl group functional group and the hydroxy functional group having hydroxy functional groups at both terminals is 10 to 40 mol%, and (c) The molar ratio of diisocyanate is preferably 50 to 70 mol%.

The minimum molar ratio of the diisocyanate monomer must be at least 50 mol% to terminate the terminal functional group with isocyanate, and if it exceeds 70 mol%, the isocyanate functional group becomes excessive and unreacted diisocyanate monomer remains.

More preferably, the molar ratio of the diisocyanate may be 50 to 67 mol%.

If the molar ratio of the dihydroxy monomer having hydroxy functional groups at both ends is less than 10 mol%, it is difficult to exhibit the inherent physical properties of the polyurethane such as elasticity and adhesion, and when it exceeds 40 mol%, the amount of DMPA that can be used is limited Difficulties arise in dispersion.

When the molar ratio of the carboxyl group functional group and the dihydroxy monomer having hydroxy functional groups at both terminals is less than 10 mol%, it is difficult to disperse the polyurethane resin prepolymer. When the molar ratio exceeds 40 mol%, the acid resistance is deteriorated due to excessive acidity.

Examples of the diol monomer having a hydroxy functional group at both terminals (a) used in the above reaction include 1,3-propanediol (1,3-PDO), 1,6-hexanediol ), 1,5-pentanediol, 2-ethyl-1,6-hexanediol, 1,4-butanediol, 1,9-nonanediol, 3- Cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, Cyclohexanediol, 1,4-cycloheptanediol, 2,5-bis (hydroxymethyl) -1,4-dioxane, 2,7-norbornanediol, tetra But are not limited to, cyclic and polycarbonate diols such as hydrofuran di-methanol, 1,4-bis (hydroxyethoxy) cyclohexane, tricyclodecane dimethanol and the like. Among them, it is preferable to use 1,3-propanediol (1,3-PDO), 1,5-pentanediol, 1,6-hexanediol (1,6-HDO)) 1,4-butanediol.

Examples of the diol monomers having a carboxyl group functional group and hydroxy functional groups at both ends of the above (b) include dimethylol-propionic acid (DMPA), diethylol-propionic acid (DEPA), di Dimethylol-propionic acid (DPPA), and the like may be used, but the present invention is not limited thereto.

The diisocyanate monomer (c) used in the reaction may be, for example, hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI) and hydrogenated methylene diphenyl diisocyanate : HMDI), or aromatic isocyanate-based compounds such as toluene diisocyanate (TDI), methylene diphenyl diisocyanate (MDI), and xylene diisocyanate (XDI) Compounds may be used, but are not limited thereto. Among them, it is preferable to use a non-sulfur-modified isocyanate compound such as HDI, IPDI or HMDI from the viewpoint of weatherability.

The reaction product was further heated to 40, dibutyl-tin-oxide (DBTO) was added in an amount of 1/1000 mole of the diisocyanate monomer, and the reaction was carried out for 8 hours to obtain a compound represented by the following formula To prepare a polyurethane resin prepolymer resin A having a terminal group terminated with an isocyanate functional group.

[Chemical Formula 1]

Wherein R ₁ , R ₂ and R ₄ are each independently an alkylene group having 6 to 20 carbon atoms, R ₃ is an alkylene group having 2 to 20 carbon atoms, k, l and m are each 1, and n is And is an integer of 1 to 100.

Here, R ₁ , R ₂ and R ₄ each independently represent an alkylene group having 6 to 15 carbon atoms.

It is more preferable that R ₃ is an alkylene group having 2 to 13 carbon atoms.

It is more preferable that n is an integer of 1 to 60.

In the second step, the polyurethane resin prepolymer resin A represented by the above formula (1) was kept at 40 and the non-toxic tertiary amine mixed at 50% with dimethyl carbonate (DMC) , 95% by mole of the dihydroxy monomer having a hydroxy functional group and having a hydroxy functional group, and the mixture is stirred for 1 hour while slowly dropping, and neutralized while being ionized.

The ionized resin is water-dispersed while stirring at a high speed of about 700 rpm while slowly adding deionized water for one hour so that the total solid content becomes 20 to 30%. When the deionized water introduction is completed, the stirring speed is lowered to 150 rpm to prepare a water-dispersible polyurethane prepolymer resin B having a terminal group terminated with an isocyanate functional group and represented by the following formula (2).

(2)

Wherein X is an amine group having an alkyl group having 1 to 20 carbon atoms, R ₁ , R ₂ and R ₄ are each independently an alkylene group having 6 to 20 carbon atoms, R ₃ is an alkylene group having 2 to 20 carbon atoms, k, l and m are each 1, and n is an integer of 1 to 100.

Also, X may be n-ethylmorpholine, but it is not necessarily so, but it is an example of a tertiary amine having non-toxicity.

The tertiary amine, which is not an accident-causing substance having non-toxicity, used in the reaction is 2-dimethylamino-2-methyl-1-propanol, DMAMP-80, Amines such as n-ethylmorpholine, dimethylaminopropanol, dimethylcyclohexylamine, and 2-methyl-2-azanorbornane may be used, but the present invention is not limited thereto. Among them, the use of ethylmorpholine is preferable in terms of maintaining a stable aqueous dispersion phase.

In addition, it is preferable that 10-50 mol% of ethylmorpholine is used at both terminals of the hydroxy functional monomer including the carboxyl group functional group to be used and the di-alcohol monomer having a hydroxy functional group at both terminals, It is preferable in terms of maintaining the dispersed phase.

The above-mentioned dimethyl carbonate (DMC) is used as a co-solvent, and the co-solvent is not necessarily limited thereto.

For reference, the substance against accident is one of the names according to the classification and labeling method of hazardous chemicals notified by the National Institute of Environmental Research. The classification and labeling methods notified by the National Institute of Environmental Research are classified into toxic substances, permissible substances, restricted substances, prohibited substances and accident-related substances.

In the third step, an alkyldiamine-based monomer having non-toxicity, which is not an accident-causing substance but excluding toxic substances such as ethylenediamine and hydrazine, is added to the water-dispersed polyurethane prepolymer resin B of the above- 3 to 10 mol% based on the amount of the diisocyanate used in the production is added to induce the urea reaction, and finally an environmentally-water-dispersible polyurethane resin resin C which can be represented by the following formula 3 having dispersion and storage stability .

When the amount of the non-toxic alkyldiamine monomer is less than 3 mol%, the isocyanate functional group remains to deteriorate the stability of the water-dispersible polyurethane resin. When the amount of the alkyldiamine monomer is less than 10 mol% There is a problem that the physical properties of the urethane resin are deteriorated such that the weather resistance and elasticity are lowered.

Examples of alkyldiamine-based monomers which are not accidental substances having non-toxicity used in the above reaction include alkyl diamines such as primary amine, 1,4-tetramethyldiamine, But are not limited to, 2-methyl-1,5-pentanediamine, 1,4-butanediamine, 1,6-hexamethylenediamine, 1,4-hexamethylenediamine , 4-hexamethylenediamine), 3-aminomethyl-3,5,5-trimethylcyclohexylamine, 1,3-bis (aminomethyl) cyclohexane amines such as -bis (aminomethyl) cyclohexane, piperazine, 2,5-dimethylpiperazine, diethylenetriamine, and triethylenetetramine may be used But is not necessarily limited thereto. Among them, the use of 1,4-butanediamine, 1,6-hexamethylenediamine, and 1,4-hexamethylenediamine is cost competitive .

 (3)

or

In the above formula, R ₆ is derived from the general formula (2), R _{5, which} is an end group, is an alkyldiamine monomer which is not an accidental substance having non-toxicity used in the third step reaction and is an alkyl group having 3 to 20 carbon atoms, ₅ is an alkylene group having 3 to 20 carbon atoms. n is an integer of 1 to 20;

The number-average molecular weight of the environmentally-water-dispersible polyurethane resin finally prepared is about 5,000 to 200,000 g / mol and the glass transition temperature is 0 to 100 ° C. It also has water dispersion characteristics.

The water-dispersed polyurethane resin contained in the coating composition of the present invention has a non-toxic nature of boiling point 90 and is a common chemical substance which is not a non-accidental substance, dimethyl carbonate having a boiling point of 90 is used as a co-solvent, Water-dispersed polyurethane resin in which tertiary amines are used as neutralizing agents, non-toxic as chain extenders, and alkyldiamine-based monomers which are not accidental materials are used.

By virtue of such physical properties and raw material composition, it is possible to provide a coating composition and a coating film which can easily completely remove the co-solvent even at a low temperature and minimize printing side effects due to blocking or residual solvent.

Furthermore, by using an environmentally-friendly water-dispersed polyurethane resin which does not contain toxic substances or accidental substances at all, the safety of toxic substances in handling, manufacturing and film manufacturing processes of the coating composition is guaranteed, And can provide an environmentally friendly coating composition that can minimize exposure of film users to toxic materials.

2. Water-dispersed polyolefin-based carboxyl (meth) acrylate copolymer

As the water-dispersed polyolefin carboxyl (meth) acrylate copolymer contained in the coating composition of the present invention, specifically, water-dispersed polyethylene (meth) acrylic acid copolymers, water-dispersed polypropylene (meth) Butylene (meth) acrylic acid copolymer, and the like. For example, Primacor 5980I, 5990I resin available from Dow Chemical as a polyethylene acrylic acid copolymer can be used. The general formula can be represented by the following formula.

In the above formula, R ₁ is an alkylene group having 2 to 12 carbon atoms, and R ₂ is hydrogen (H) or a methyl group. Also, l is 1 to 20, m is 1 to 10, and n is 10 to 3000. [

Among these resins, Primacor 5980I resin is known to have a copolymerization ratio of ethylene and acrylic acid of 79.5: 20.5 by weight, wherein the neutralization factor is 0.75.

When the weight ratio is converted into the molar ratio of ethylene and acrylic acid monomer, it is understood that about 2.85 mol of acrylic acid is contained per 1000 g of resin, and that the carboxy functional group participating in neutralization is 75 mol% of 2.85 mol.

With reference to the above information, a 2L three-necked glass reactor was prepared to disperse the Primacor 5980I resin in water, 750 g of deionized water and 250 g of Primacor 5980I resin were placed, and a condenser was installed by raising the temperature to 95 ° C . The non-toxic tertiary amine as a neutralizing agent was added in an amount of 50 to 90 mol% based on the molar amount of acrylic acid in the resin of Primacor 5980I and reacted for 8 hours while stirring at a rate of 150 rpm to obtain a water dispersed polyolefin carboxyl (meth) acrylate copolymer To prepare a resin solution.

When the amount of the tertiary amine used is 50 mol% or less, it is difficult to dissolve the Primacor 5980I resin. When the amount of the tertiary amine is 90 mol% or more, there is a problem that the viscosity increases exponentially due to excessive neutralization.

The tertiary amine, which is not an accident-causing substance having non-toxicity, used in the reaction is 2-dimethylamino-2-methyl-1-propanol, DMAMP-80, Amines such as n-ethylmorpholine, dimethylaminopropanol, dimethylcyclohexylamine, and 2-methyl-2-azanorbornane may be used, but the present invention is not limited thereto. Among them, the use of ethylmorpholine, 2-dimethylamino-2-methyl-1-propanol and DMAMP-80 as commercialized materials, .

The water-dispersed polyolefin-based carboxyl (meth) acrylate copolymer contained in the coating composition of the present invention is a polyolefin-based carboxyl (meth) acrylate copolymer having a copolymerization ratio of acrylic acid of 18 to 30% by weight, an ethylene monomer of 70 to 82 weight%; And (b) 30 to 75 mol% of a neutralizing agent used for water dispersion of the polyethylene acrylic acid copolymer resin, relative to acrylic acid used for copolymerization, of a tertiary amine which is not an accident-causing substance having non-toxicity; And the like. If it is less than 30 mol%, it may not be dispersed in water. If it is used in excess of 75 mol%, the effect is insignificant.

3. Water dispersion Polyacrylate  Copolymer

The water-dispersed polyacrylate copolymer having a glass transition temperature of 50 to 120 ° C, which is prepared using a nonionic surfactant contained in the coating composition of the present invention, can be produced by a conventional emulsion polymerization method, (Meth) acrylate copolymer, polymethyl methacrylate (meth) acrylate copolymer, polymethyl methacrylate butyl (meth) acrylate (meth) acrylic acid copolymer, polymethyl methacrylate ethyl (Meth) acrylic acid copolymer, polystyrene methyl (meth) acrylate (meth) acrylic acid copolymer, polystyrene butyl (meth) acrylate (meth) acrylic acid copolymer, polystyrene ethyl Methacrylate (meth) acrylic acid copolymer, polystyrene methyl methacrylate butyl (meth) acrylate (meth) acrylate, (Meth) acrylate copolymer may be used. For example, a copolymer of polymethyl methacrylate and acrylic acid, such as NP- 960 resin can be used.

The NP-960 resin had a glass transition temperature of 105 ° C, a weight average molecular weight of about 1,200,000 g / mol, and a solid content of 50%.

The water-dispersed polyacrylate copolymer resin having a glass transition temperature of 50 to 120 DEG C is obtained by (a) a water-dispersed polyacrylate copolymer resin prepared by emulsion polymerization using a nonionic surface active agent as a main emulsifier; And (b) a glass transition temperature in the range of 50 to 120 占 폚.

In order to prevent the gelation of the water-dispersed polyolefin resin and the fully neutralized water-dispersed polyurethane resin to which the partially neutralized carboxyl functional group is added, the above-mentioned water-dispersed polyacrylate copolymer is used in order to prevent the shock of the ionic emulsifier But it can prevent the blocking between the films after coating by the effect of the high glass transition temperature while effectively improving the storage stability.

The water-dispersed polyacrylate copolymer resin contained in the coating composition of the present invention comprises (a) a water-dispersed polyacrylate copolymer resin prepared by emulsion polymerization using a nonionic surfactant as a main emulsifier; And (b) a water-dispersed polyacrylate copolymer resin having a glass transition temperature of 50 to 120 ° C.

4. Coating composition

The hard coat composition of the present invention comprises the above-described i) an environmentally-water-dispersible polyurethane resin, ii) a water-dispersed polyolefin-based carboxyl (meth) acrylate copolymer resin, and iii) a water-dispersed polyacrylate copolymer.

More specifically, the coating composition of the present invention comprises 100 parts by weight of (i) 100 parts by weight of an environmentally-friendly water-dispersed polyurethane resin solid, ii) 60 to 150 parts by weight of a water-dispersible polyolefin-based carboxyl (meth) And iii) 60 to 150 parts by weight of a water-dispersed polyacrylate copolymer solid basis resin.

More preferably, the coating composition of the present invention comprises i) 100 parts by weight of an environmentally-water-dispersible polyurethane resin solids, ii) 80 to 120 parts by weight of a water-dispersed polyolefin-based carboxyl (meth) acrylate copolymer solids, and iii ) ≪ / RTI > water-dispersed polyacrylate copolymer solids.

Other additives

The coating composition of the present invention may contain other conventional additives in addition to the environmentally-water-dispersible polyurethane resin, the water-dispersed polyolefin-based carboxyl (meth) acrylate copolymer resin and the water-dispersed polyacrylate copolymer resin. Such additives include slip additives and surfactants.

Use of these other additives doubles the scratch resistance and blocking effect and increases the effect of improving the appearance properties of the coating

As the slip additive, silicone slip additive, acrylic slip additive, and fluorine slip additive can be used, but not always limited thereto. Examples of slip additives commercialized in the industry include BYK-348, BYK-330, BYK-310 and BYK-307, which are silicon-based products, and F-470, a fluorine- There is a kind of slip additive.

The slip additive may be used in an amount of 0.02 to 2 parts by weight, preferably 0.1 to 1 part by weight, based on 100 parts by weight of the resin solid content contained in the entire coating composition. If the content of the slip additive is less than 0.02 parts by weight, the effect of adding the slip additive in the coating film is hardly expected. If the amount of the slip additive is more than 2 parts by weight, the ink adhesion performance may be lowered due to the excessive slip additive.

As the surfactant, it is preferable to use a nonionic surfactant having a hydrophilic group and an aliphatic oil component as a hydrophobic group by controlling the number of moles of ethylene oxide, but not always limited thereto. The nonionic surfactant may be selected from, for example, a commonly used product family such as Tween 20, 40, 60, 80, or Surfynol-104 or Surfynol-440 series of Air Products.

The surfactant may be used in an amount of 0.05 to 3 parts by weight, preferably 0.1 to 2 parts by weight, based on 100 parts by weight of the resin solid content contained in the entire coating composition. When the content of the surfactant is less than 0.05 part by weight, it is difficult to expect improvement in wettability at the time of coating, and when it exceeds 3 parts by weight, the water resistance is deteriorated due to an excessive surfactant effect.

5. Coating film

The film of the present invention is a film prepared by coating a substrate composition with a coating composition composed of the above-defined composition.

More specifically, the film of the present invention comprises a base film layer; And a coating layer formed by coating a coating composition on the upper or both surfaces of the base film layer; Can be made into a laminated film.

Further, the film of the present invention comprises a base film layer; A coating layer formed by coating a coating composition on or above the base film layer; Can be made into a laminated electrostatic printing film.

The base film layer may be formed of at least one of a polypropylene resin, a polyethylene resin, a polyamide resin, a polyester resin, a polyacrylic resin, a polyvinyl chloride resin, a polycarbonate resin, a urethane resin, And a composite material may be used. In the present invention, various materials may be used without particular limitation on the selection of the substrate material.

The thickness of the base film layer may be in the range of about 12 to 400 mu m, preferably 20 to 300 mu m. If the thickness of the base film layer is less than 12 mu m, it may be difficult to control the coating tension due to too thin substrate thickness. If the thickness is more than 400 mu m, feeding into the electrostatic type printing printer may not be smooth.

The coating layer may be formed by coating the coating composition of the present invention.

Specifically, the coating composition may be coated on one surface of the base film layer and then heated at a temperature of about 80 to 150 ° C for about 30 seconds to 2 minutes to form a coating film. The thickness of the coating layer may range from approximately 0.5 to 40 mu m.

If the thickness of the coating layer is less than 0.5 mu m, there is a risk of deterioration of the ink adhesion, and if the thickness exceeds 40 mu m, deterioration in substrate adhesion performance may occur.

Hereinafter, the present invention will be described in more detail with reference to Examples.

However, the following examples are illustrative of the present invention, and the contents of the present invention are not limited by the following examples.

[Example]

Manufacturing example  1. Eco-friendly Water dispersion  Manufacture of polyurethane resin

1-1) A mixture of 3.5 g of 1,3-propanediol (1,3-PDO), 15.9 g of 1,6-hexanediol (1,6-HDO) and 109.2 g of hexamethylene diisocyanate (HDI) And the mixture was stirred at room temperature for 30 minutes. 39 g of dimethylolpropionic acid (DMPA) was mixed with 156 g of dimethyl carbonate (DMC), and the mixture was stirred at 150 rpm while being slowly added to the reactor for 30 minutes.

1-2) The above reaction was heated to 40 ° C, and 0.2 g of dibutyltin oxide was added to the reactor and reacted for 8 hours.

1-3) 78 g of 2-dimethylamino-2-methylpropanol (DMAMP-80) was mixed with 78 g of dimethyl carbonate (DMC) while maintaining the temperature of the reaction at 40 ° C., And stirred for 1 hour while pinging.

1-4) While stirring the reaction product at about 700 rpm at high speed, 500 g of deionized water was slowly dispersed in water for one hour.

1-5) After one hour, the stirring speed was lowered to 150 rpm, 4.1 g of 1,6-hexylenediamine (HDA) was added, the temperature was maintained at 60 ° C. for 2 hours, and the reaction was terminated.

The water-dispersed polyurethane resin had a number average molecular weight of 52,000 g / mol, a glass transition temperature of 42 캜, and a solid content of 25.3%.

The water-dispersed polyurethane resin intermediate A prepared by the reaction of Production Example 1-2) has the following chemical structure.

In the above formula, R ₁ is an alkylene group having 6 carbon atoms, R ₂ is an alkylene group having 3 carbon atoms, and R ₃ is an alkylene group having 6 carbon atoms. The number average molecular weight of the resin thus prepared was about 1,000 g / mol.

The water-dispersed polyurethane resin finally prepared by the reaction of Production Example 1-5 has the following chemical structure.

또는

or

In the above formula, R6 is Preparation Example 1-2) and the main chain derived from the reaction of intermediate A prepared, the terminal group R ₅ is an alkyl group having a carbon number of 6, the connection group R ₅ is an alkylene group of a carbon number of 6, the preparation The number average molecular weight of the resin was about 2,000 g / mol.

Production Example 2. Preparation of water-dispersed polyolefin-based carboxyl (meth) acrylate copolymer resin

A condenser is installed in a 2 L three-necked reactor, and 250 g of a Primacor 5980I resin and 750 g of deionized water are charged, and the mixture is refluxed while raising the temperature to 95 ° C. 60 g of 2-dimethylamino-2-methylpropanol (DMAMP-80) was added and reacted for 8 hours while stirring at a speed of 150 rpm to obtain a water-dispersed polyolefin-based carboxyl (meth) To prepare a resin solution.

The solid content of the prepared water-dispersed polyolefin-based carboxyl (meth) acrylate copolymer resin solution was 25.2%.

Production Example 3. Preparation of water-dispersed polyolefin-based carboxyl (meth) acrylate copolymer resin

The production process is the same as in Production Example 2 except that polyethyleneacrylic acid resin is used in the preparation of the water-dispersed polyolefin carboxyl (meth) acrylate copolymer resin solution.

Example  1. Coating composition

100 parts by weight of the water-dispersed polyurethane resin solution prepared in Preparation Example 1, 100 parts by weight of the water-dispersed polyolefin-based carboxyl (meth) acrylate copolymer resin prepared in Preparation Example 2, 100 parts by weight of the water-dispersed polyacrylate copolymer 50 0.2 parts by weight of BYK-333 as a slip additive and 0.5 parts by weight of Surfynol-440 as a surfactant were mixed and diluted with deionized water to obtain a final solid content of 15% by weight Lt; / RTI >

Example  2. Coating composition

100 parts by weight of the water-dispersed polyurethane resin solution prepared in Preparation Example 1, 100 parts by weight of the water-dispersed polyolefin-based carboxyl (meth) acrylate copolymer resin prepared in Preparation Example 3, 100 parts by weight of the water-dispersed polyacrylate copolymer 50 0.2 parts by weight of BYK-333 as a slip additive and 0.5 parts by weight of Surfynol-440 as a surfactant were mixed and diluted with deionized water to obtain a final solid content of 15% by weight Lt; / RTI >

Example  3. Coating composition

100 parts by weight of the water-dispersed polyurethane resin solution prepared in Preparation Example 1, 100 parts by weight of the water-dispersed polyolefin-based carboxyl (meth) acrylate copolymer resin prepared in Preparation Example 2, 0.12 by weight BYK- And 0.3 part by weight of Surfynol-440 as a surfactant were mixed and diluted with deionized water to prepare a coating composition having a final solid content of 15% by weight.

Example  4. Coating composition

100 parts by weight of the water-dispersed polyurethane resin solution prepared in Preparation Example 1, 100 parts by weight of the water-dispersed polyolefin-based carboxyl (meth) acrylate copolymer resin prepared in Preparation Example 2, 100 parts by weight of Ceramate wax additive BYK -250, 0.12 parts by weight of BYK-333 as a slip additive and 0.3 parts by weight of Surfynol-440 as a surfactant were mixed and diluted with deionized water to prepare a coating composition having a final solid content of 15% by weight.

Comparative Example  1. Coating composition

Except that dimethylformamide (DMF) was used instead of dimethyl carbonate (DMC) in the production of the water-dispersed polyurethane resin solution in Production Example 1-1), the production process was the same as in Production Example 1, 100 parts by weight of the water-dispersed polyurethane resin solution, 100 parts by weight of the water-dispersed polyolefin carboxyl (meth) acrylate copolymer resin prepared in Preparation Example 3, 50 parts by weight of the water-dispersed polyacrylate copolymer (NP- 0.2 parts by weight of BYK-333 as a slip additive and 0.5 part by weight of Surfynol-440 as a surfactant were mixed and diluted with deionized water to prepare a coating composition having a final solid content of 15% by weight.

Comparative Example  2. Coating composition

100 parts by weight of a water-dispersed polyurethane prepared by the same manufacturing process except that dimethylsulfoxide (DMSO) was used in place of dimethylformamide (DMF) in the preparation of the water-dispersed polyurethane resin solution in the coating composition of Comparative Example 1, 100 parts by weight of the water-dispersed polyolefin carboxyl (meth) acrylate copolymer resin prepared in Preparation Example 3, 50 parts by weight of water-dispersed polyacrylate copolymer (NP-960, manufactured by NPCHEM, solid content 50% 0.2 parts by weight of BYK-333 as an additive and 0.5 parts by weight of Surfynol-440 as a surfactant were mixed and diluted with deionized water to prepare a coating composition having a final solid content of 15% by weight.

Comparative Example  3. Coating composition

The water-dispersed poly (urethane) resin prepared in the same manufacturing process except for using methyl-2-pyrrolidone (NMP) in place of dimethylformamide (DMF) 100 parts by weight of urethane, 100 parts by weight of the water-dispersed polyolefin-based carboxyl (meth) acrylate copolymer resin prepared in Preparation Example 3, 50 parts by weight of an aqueous dispersion polyacrylate copolymer (NP-960, 0.2 part by weight of BYK-333 as a slip additive and 0.5 part by weight of Surfynol-440 as a surfactant were mixed and diluted with deionized water to prepare a coating composition having a final solid content of 15% by weight.

Experimental Example 1 . Preparation of coating film specimens

Each of the coating compositions prepared above was coated on both surfaces of a polypropylene (PP) substrate without a primer treatment of a thickness of 100 mu m and a width of 1,080 mm to a dry film thickness of 1 mu m by a bar coating method, And dried at 120 ° C for 1 minute to prepare coating film samples for evaluation for each coating composition.

Experimental Example 2 . Printing specimen  Produce

In order to evaluate the printing properties of the prepared coating film, each of the coating films prepared above was cut into A3 standard, and each coating film prepared in Experimental Example 1 was coated using Indigo 5500 printer manufactured by HP And printed on one side of the film sample to prepare a printing sample for evaluation.

[Property evaluation method]

(One) Base Attachment  evaluation

The coating film specimens for evaluation for each coating composition prepared in Experimental Example 1 were prepared to have a size of 200 mm X 100 mm. The adhesive tape manufactured by 3M Company was laminated on the coating layer side by 100 mm using a 1 kg load roller, Min.

After 30 minutes, the coating layer was peeled off at a speed of 300 mm / min from the angle of 180 °, and then the peeling of the coating layer was confirmed by the visual inspection method. "O: excellent (no overtapping) X: poor (many transitions occurred) ".

(2) Ink adhesion  evaluation

Each of the test specimens for evaluation of each coating film prepared in Experimental Example 2 was prepared to have a size of 200 mm X 100 mm, and the adhesive tape manufactured by 3M Company was laminated to the surface of the coating layer by 100 mm using a 1 kg load roller. Respectively.

After 30 minutes, the coating layer was peeled off at a speed of 300 mm / min from the angle of 180 °, and then the peeling of the coating layer was confirmed by the visual inspection method. "O: excellent (no overtapping) X: poor (many transitions occurred) ".

(3) Evaluation of storage stability

Each of the coating compositions prepared in the above Examples and Comparative Examples was immersed in a 50 ml vial, and then allowed to stand in an 80 convection oven for 7 hours. The gelation was evaluated every 1 day by the viscometric method and evaluated by the date of occurrence of viscosity change.

(4) Evaluation of blocking characteristics

Coating film specimens for evaluation of each coating composition prepared in Experimental Example 1 were prepared in a size of 200 mm x 200 mm and then stacked in a stack of 10 sheets. The specimens were placed in a glass convection oven having a thickness of 5 mm and placed in a 60 convection oven. , And the state of sticking between the films was evaluated as "O: excellent (not sticking), Δ: normal (sticking to the edge portion) and X: poor (sticking to the whole)".

(5) Residual organic solvent ( TVOC ) evaluation

The coated film specimens for evaluation according to each coating composition prepared in Experimental Example 1 were prepared to have a size of 100 mm x 100 mm and then subjected to a test using the Emission test chamber method (Small), (EN / ISO 16000-9) The content of TVOC was compared by GC-MS analysis.

The respective results evaluated by the physical property evaluation method are shown in Table 1 as an average value.

Table 1 shows that the specimens prepared using the coating compositions of Examples 1 to 4 proposed by the present invention are coating films capable of electrostatically printing due to good substrate adhesion and ink adhesion as compared with Comparative Examples 1 to 3 Respectively.

In addition, it was confirmed that the storage stability was greatly improved by mixing an emulsion-polymerized water-dispersed polyacrylate copolymer using a nonionic surfactant. It was confirmed that the method of blending the water-dispersed polyacrylate copolymer having a higher glass transition temperature than the effect of using the wax was effective for the anti-blocking property.

In addition, it has been confirmed that the use of the environmentally friendly polyurethane resin according to the present invention has the effect of significantly reducing TVOC emission.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention as defined in the appended claims. It is to be understood that the invention is capable of various modifications and alterations of the invention.

Claims (24)

(a) a dialcohol monomer having hydroxy functional groups at both terminals;
(b) a dialcohol monomer having a carboxyl group functional group and hydroxy functional groups at both terminals; And
(c) diisocyanate monomers having isocyanate functional groups at both terminals;
(I) comprising a main chain derived from a polymer of the polyurethane resin,
(Ii) a water-dispersed polyolefin-based carboxyl (meth) acrylate copolymer resin and (iii) a water-dispersed polyacrylate copolymer resin.
The method according to claim 1,
Wherein the environmentally friendly polyurethane resin has the following formula:
(3)

or

In the formula, R ₆ is to be represented by the following formula, the terminal group R ₅ is an alkyl group having 3 to 20 carbon atoms, connected group R ₅ is an alkyl group having 3 to 20 carbon atoms, n is an integer from 1 to 20;
[Chemical Formula]

Wherein X is an amine group having an alkyl group having 1 to 20 carbon atoms, R ₁ , R ₂ and R ₄ are each independently an alkylene group having 6 to 20 carbon atoms, R ₃ is an alkylene group having 2 to 20 carbon atoms, k, l and m are each 1, and n is an integer of 1 to 100.
The method according to claim 1,
Wherein the environmentally friendly polyurethane resin has a number average molecular weight of 5,000 to 200,000 g / mol and a glass transition temperature of 0 to 100 ° C.
The method according to claim 1,
The environmentally friendly polyurethane resin
The molar ratio of the dihydroxy functional group-containing functional group and the hydroxy functional group-containing diol monomer at both terminals is 10 to 40 mol%, the molar ratio of the dihydroxy functional group-containing dihydroxy functional group to the (a) And (c) the molar ratio of the diisocyanate monomer is 50 to 70 mol%.
The method according to claim 1,
The diol monomer having a hydroxy functional group at both terminals of (a) is selected from 1,3-propanediol, 1,6-hexanediol, 1,5-pentanediol, 2-ethyl-1,6- Butanediol, 3-methyl-1,5-pentanediol, 2-methyl-1,8-octanediol, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol And aliphatic polypropylene glycols; And 1,4-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanediol, 1,3-cyclopentanediol, 1,4-cycloheptanediol, 2,5-bis (Cyclohexane) -cyclohexane and cyclic decanedimethanol, which are cyclic of 1, 4-dioxane, 2,7-norbornanediol, tetrahydrofuran dimethanol, 1,4-bis (hydroxyethoxy) Lt; RTI ID = 0.0 > 1, < / RTI >
The method according to claim 1,
The diol monomer having a carboxyl group functional group and hydroxy functional groups at both ends of the above (b) is selected from the group consisting of dimethylol-propionic acid (DMPA), diethylol-propionic acid (DEPA) Wherein the coating composition is at least one selected from the group consisting of dimethylol-propionic acid (DPPA).
The method according to claim 1,
The diisocyanate monomer having an isocyanate functional group at both terminals (c) is an aliphatic or cyclic isocyanate compound selected from the group consisting of hexamethylene diisocyanate, isophorone diisocyanate and hydrogenated methylenediphenyl diisocyanate; And aromatic isocyanate-based compounds selected from the group consisting of toluene diisocyanate, methylene diphenyl diisocyanate, and xylene diisocyanate; ≪ / RTI >
delete delete delete delete delete delete delete delete The method according to claim 1,
And the iii) water-dispersed polyacrylate copolymer resin has a glass transition temperature of 50 to 120 ° C.
The method according to claim 1,
(Ii) 60 to 150 parts by weight of the water-dispersed polyolefin-based carboxyl (meth) acrylate copolymer resin solid component, and (iii) the water-dispersed polyacrylate Lt; RTI ID = 0.0 > 60-150 < / RTI > parts by weight of the latex copolymer resin solids.
The method according to claim 1,
(Ii) the water-dispersed polyolefin-based carboxyl (meth) acrylate copolymer resin is a water-dispersed polyethylenic (meth) acrylic acid copolymer, an aqueous dispersion polypropylene (meth) acrylic acid copolymer, and an aqueous dispersion polybutylene And at least one selected from the group consisting of a metal oxide, a metal oxide, and a metal oxide.
The method according to claim 1,
(Iii) the water-dispersed polyacrylate copolymer resin is at least one selected from the group consisting of polymethyl methacrylate (meth) acrylic acid copolymer, polymethyl methacrylate butyl (meth) acrylate (Meth) acrylic acid copolymers, polystyrene (meth) acrylic acid copolymers, polystyrene methyl (meth) acrylate (meth) acrylic acid copolymers, polystyrene butyl (meth) (Meth) acrylic acid copolymer, polystyrene methyl methacrylate (meth) acrylic acid copolymer, polystyrene methyl methacrylate butyl (meth) acrylate (meth) acrylic acid copolymer, and polystyrene methyl methacrylate ethyl (meth) Acrylate (meth) acrylic acid copolymer, and at least one selected from the group consisting of ≪ / RTI >
The method according to claim 1,
(Ii) the water-dispersed polyolefin-based carboxyl (meth) acrylate copolymer resin comprises (a) a polyethylene acrylic acid copolymer resin having a copolymerization ratio of acrylic acid of 18 to 30% by weight and an ethylene monomer of 70 to 82% by weight; And (b) a neutralizing agent used for water dispersion of the polyethylene acrylic acid copolymer resin is prepared from 30 to 75 mol% of a tertiary amine which is not an accident-prone substance having non-toxicity relative to acrylic acid used for copolymerization Coating composition.
The method according to claim 1,
The iii) water-dispersed polyacrylate copolymer is prepared by (a) an aqueous dispersion polyacrylate copolymer resin prepared by emulsion polymerization using a nonionic surfactant as an emulsifier; And (b) a water-dispersed polyacrylate copolymer resin having a glass transition temperature of 50 to 120 ° C.
The method according to claim 1,
A slip additive, and a surfactant. A base film layer; And
Wherein a coating layer formed by applying and thermosetting the coating composition of any one of claims 1 to 7 and claims 16 to 22 is laminated on the upper or both sides of the base film layer.
24. The method of claim 23,
Wherein said film is an electrostatic printing film.