KR101911901B1 - Lacquer composition and a method thereof - Google Patents

Abstract

The present invention provides a lacquer composition which comprises a modified alkyd acrylic resin, a dimethyl carbonate and an aliphatic saturated hydrocarbon-based solvent having 5 to 10 carbon numbers, and a manufacturing method thereof. The present invention reduces a generation amount of a volatile organic compound in manufacturing and working processes of the lacquer composition to improve hygiene health of a worker, adjusts a volatile speed of the solvent to implement an improved physical property and can solve a freezing problem of the lacquer composition generated in a low temperature environment such as the winter season.

Description

Lacquer composition and a method thereof < RTI ID = 0.0 >

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lacquer composition for forming a glossy film on the surface of an object such as a building, furniture, electric wire, etc., and a method for producing the lacquer composition. More specifically, the present invention relates to a lacquer composition capable of reducing the generation of volatile organic compounds Solvent and an aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms, which are environmentally friendly and free from the problem of freezing of the lacquer when working at a low temperature, and to a process for producing the lacquer composition.

The lacquer is used to give a solid film on the surface of objects such as buildings, furniture, electric wires and so on, thereby giving the surface of the object an antifouling, antirust, flame retardant, waterproof, The resin is prepared by diluting the resin, and the kinds of the resin and the solvent used therein are very various.

As the resin, a thermoplastic resin such as an acrylic resin, a vinyl chloride resin, a polyethylene resin and a polyamide imide resin and a thermosetting resin such as an epoxy resin, a urethane resin, a polysulfone resin and a phenol resin can all be used.

At this time, a thermally water-soluble resin such as polyethylene can dissolve in various solvents and has excellent processability. On the other hand, since the solvent has volatilized, it has relatively low physical properties on the surface of the substrate, The resin has excellent physical properties after the solvent is volatilized, but the resin is dissolved only in a high-performance solvent having high solubility, so there is a limitation on the kinds of the solvent used for dissolving the polysulfone resin.

On the other hand, as the solvent, various solvents such as an aliphatic hydrocarbon solvent, an aromatic hydrocarbon solvent, an ester solvent or a ketone solvent can be used, and toluene and xylene are mainly used.

However, most of the solvents including the above solvents are volatile and emit volatile organic compounds harmful to the human body during the volatilization process, which may lead to problems such as deterioration of work environment and sick house syndrome.

In addition to these problems, the regulations on environmentally harmful substances have been strengthened throughout the world. In the paint industry, research and development of paints to cope with such environmental regulations have been carried out. However, environmentally friendly lacquer products Has not yet been developed.

Korean Patent Registration No. 0918097 discloses a polyester lacquer produced by reacting dimethyl terephthalate with tris-2-hydroxyethyl isocyanurate as an insulating lacquer for electric wires. Unlike the conventional enamel lacquer, an aromatic organic solvent It is eco-friendly, but it has properties that are not suitable for use as a general purpose paint other than wire coating.

Korean Patent Laid-Open Publication No. 2017-0089186 discloses a solvent-free alkyd resin, which is obtained by condensation reaction of an unsaturated fatty acid, a polybasic acid and a polyhydric alcohol, and optionally an addition reaction of an isocyanate or an acrylic monomer, The present invention provides a paint obtained by emulsifying a resin with a surfactant and water, and is free from harmful substances such as VOCs because it does not use a solvent. However, it is difficult to obtain appropriate physical properties with the above- there is a problem.

Various attempts have been made to produce eco-friendly lacquers as shown in the existing prior art documents, but no lacquer compositions satisfying all the properties of physical properties, processability and low toxicity as lacquer have been developed yet.

Registration No. 10-0918097 (registered on September 11, 2009) Open Patent No. 10-2017-0089186 (published on Aug. 31, 2017)

The present invention includes a modified alkyd acrylic resin, dimethyl carbonate, and an aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms, thereby reducing the amount of volatile organic compounds generated, improving sanitary health of a worker during lacquer application, To provide a lacquer composition having improved physical properties and a process for producing the same.

In order to accomplish the above object, an embodiment of the present invention is a method for producing an aliphatic saturated hydrocarbon-based solvent 7 having 20 to 40% by weight of a modified alkyd acrylic resin, 22.5 to 72.5% by weight of dimethyl carbonate, and 5 to 10% To 50% by weight of the composition.

The modified alkyd acrylic resin is obtained by copolymerizing a modified alkyd resin with at least one monomer selected from the group consisting of a styrene monomer, a butyl acrylate monomer, and a methyl methacrylate monomer, ≪ / RTI >

The modified alkyd resin may be selected from the group consisting of phthalic anhydride; Soybean fatty acid or rice bran fatty acid; Glycerin; And pentaerythritol. ≪ / RTI >

The aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms preferably includes Methyl Cyclohexane, Methyl Hexane, Dimethyl Cyclopentane, and Heptane.

At this time, the lacquer composition may further include butyl acetate in an amount of 40 wt% or less.

Meanwhile, another embodiment of the present invention relates to a method for producing a lacquer composition comprising: a phthalic anhydride; Soybean fatty acid or rice bran fatty acid; Glycerin; A step of mixing a modified alkyd resin with a styrene monomer, a butylacrylate monomer, and a methyl methacrylate to prepare a modified alkyd resin; mixing the modified alkyd resin and the pentaerythritol; A second step of reacting the modified alkyd acrylic resin with at least one monomer selected from the group consisting of methyl methacrylate monomer and 20 to 40% by weight of the modified alkyd acrylic resin, (Dimethyl carbonate) solvent having a carbon number of 5 to 10 and an aliphatic saturated hydrocarbon having a carbon number of 5 to 10 so as to satisfy a compositional ratio of 22.5 to 72.5% by weight of an aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms and 7 to 50% And a third step of mixing the hydrocarbon-based solvent.

In the first step, 100 parts by weight of phthalic anhydride; 150 to 190 parts by weight of soybean fatty acid or rice bran oil fatty acid; 15 to 55 parts by weight of glycerin; And 40 to 60 parts by weight of pentaerythritol, and then heating the mixture to a temperature ranging from 200 to 220 ° C .; A cooling step of cooling the temperature to 100 DEG C or lower; And a diluting step of adding dimethyl carbonate to the dehydrated alkyd resin, wherein xylene is added between the step of preparing the modified alkyd resin and the cooling step to dehydrate the product, and then the acid value is in the range of 5 to 6 And recovering the xylene when it is reached.

In the second step, 40 to 150 parts by weight of dimethyl carbonate is further mixed with 100 parts by weight of the modified alkyd resin obtained in the first step, and then the temperature is raised to 85 to 95 ° C ; 50 to 350 parts by weight of at least one monomer selected from the group consisting of a styrene monomer, a butylacrylate monomer and a methyl methacrylate monomer is mixed with the modified alkyd resin ; And 31 to 160 parts by weight of dimethyl carbonate, and then maintaining the mixture for a predetermined period of time.

The aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms preferably includes 30 to 40% by weight of methyl cyclohexane, 30 to 40% by weight of methyl hexane, 6 to 18% by weight of dimethyl cyclopentane, , And heptane (Heptane) in an amount of 1 to 5% by weight.

On the other hand, in the third step, butyl acetate may be further mixed in the range of 40 wt% or less.

The present invention provides a lacquer composition comprising a modified alkyd acrylic resin, dimethyl carbonate, and an aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms, and a process for producing the same, thereby reducing the amount of volatile organic compounds generated during the production and processing of the lacquer composition, And the volatilization rate of the solvent can be controlled so that the improved physical properties can be expressed and the freezing problem of the lacquer composition occurring in a low temperature environment such as winter can be solved.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. As well as the fact that

Throughout this specification, when an element is referred to as " including " an element, it is understood that it may include other elements as well, without departing from the other elements unless specifically stated otherwise.

Throughout this specification, "%" used to denote the concentration of a particular substance is intended to include solids / solids (weight / weight), solid / liquid (weight / volume) / Liquid means (volume / volume)%.

Hereinafter, the lacquer composition of the present invention and its preparation method will be described in more detail. The lacquer is the same as the varnish, and the composition named lacquer throughout the specification means lacquer or varnish.

First, the lacquer composition according to one embodiment of the present invention includes a modified alkyd acrylic resin, dimethyl carbonate, and an aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms.

The modified alkyd acrylic resin is a substance which is applied to the surface of an object such as a building, furniture, electric wire or the like to give the surface of the object a function of antifouling, rust prevention, flame proofing, The composition may be contained in an amount of 20 to 40% by weight based on the environmentally friendly lacquer composition.

When the modified alkyd acrylic resin is used in an amount of less than 20% by weight, sufficient physical properties can not be imparted to the composition, and the adhesion and corrosion resistance of the composition may be significantly deteriorated. When the composition is used in an amount exceeding 40% by weight, It is preferable that the modified alkyd acrylic resin is included in the composition range because the surface of the lacquer is formed with curvature and unevenness to degrade surface smoothness and esthetics.

The modified alkyd acrylic resin may be obtained through reaction of a modified alkyd resin with a monomer, and the modified alkyd resin may be an alkyd resin, which is a polymer substance formed by a condensation reaction of a polyhydric alcohol and a polyhydric acid, Fatty acids. ≪ / RTI >

The polybasic acid as a raw material of the alkyd resin is an acid containing two or more hydrogen atoms capable of neutralizing a base in one molecule and is selected from phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, At least one polybasic acid selected from the group consisting of phthalic anhydride, 4-methyl-hexahydrophthalic anhydride, trimellitic anhydride, succinic anhydride, and maleic anhydride can be used.

The polyhydric alcohol which is another raw material of the alkyd resin is an alcohol having two or more hydroxy groups in one molecule, and examples thereof include ethylene glycol, diethylene glycol, polyethyleneglycol, propylene glycol, dipropylene glycol, 1,3-butylene glycol, iso At least one polyhydric alcohol selected from the group consisting of pentyl diol, pentylene glycol, 1,2-hexanediol, hexylene glycol and glycerin can be used.

Examples of the fat or oil which induces denaturation of the alkyd resin include sucrose fatty acid, catechin fatty acid, soybean fatty acid, rice bran fatty acid, rapeseed fatty acid, sunflower fatty acid, safflower fatty acid, lactic acid fat acid, cottonseed fatty acid, Olive oil fatty acid, castor oil fatty acid, linseed oil preservative, walnut oil preservative, linseed oil fatty acid, linoleic acid and oleic acid.

Since the modified alkyd resin can be formed by a combination of various raw materials, the physical properties of the resin can be variously changed by controlling the kinds and amounts of these raw materials, and the possibility of denaturation is great, so that the alkyd resin can be used alone, In many cases.

In the present invention, a modified alkyd resin modified with soybean fatty acid is used as an alkyd resin produced by using phthalic anhydride as a polybasic acid as a modified alkyd resin and glycerin as a polyhydric alcohol.

Specifically, the modified alkyd resin is a modified alkyd resin prepared by reacting 150 to 190 parts by weight of soybean fatty acid or rice bran fatty acid, 15 to 55 parts by weight of glycerin, and 40 to 60 parts by weight of pentaerythritol with respect to 100 parts by weight of phthalic anhydride.

The modified alkyd acrylic resin can be obtained through the reaction of the modified alkyd resin produced with such a composition ratio with the monomer. At this time, in order to provide a lacquer composition which is not only excellent in functions such as surface hardness, antifouling property, antifouling property, flame retardancy, waterproof property and gloss property required as a lacquer composition but also economically, 100 parts by weight of a monomer 50 To 350 parts by weight of the modified alkyd acrylic resin.

The monomers used to obtain the modified alkyd acrylic resin are generally usable as long as they are components used in acrylic paints. For example, there may be mentioned methyl acrylate, ethyl acrylate, butyl acrylate, isopropyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, isopropyl ketacrylate, n- Acrylic acid, methacrylic acid, maleic acid, itaconic acid, 2-hydroxyethylmethacrylate, hydroxymethacrylate, 2-hydroxypropylmethacrylate, isopropylmethacrylate, isobutylmethacrylate, n-hexylmethacrylate, laurylmethacrylate, At least one monomer selected from the group consisting of ethyl acrylate, acrylamide, n-methylolacrylamide, diacetone acrylamide, glycidyl methacrylate, styrene, vinyltoluene, vinyl acetate and acrylonitrile monomers is Can be used.

Preferably, at least one monomer selected from the group consisting of styrene, butyl acrylate, and methyl methacrylate can be used.

As described above, the modified alkyd acrylic resin may be prepared by reacting a modified alkyd resin with a monomer, and may further include at least one of an initiator and an additive in the reaction.

The initiator is an initiator for synthesizing a modified alkyd acrylic resin and may be added in an amount of 2 to 20 parts by weight based on 100 parts by weight of the modified alkyd resin. When the amount of the modified alkyd acrylic resin is less than the above range, that is, when it is added in an amount less than 2 parts by weight, the synthesis is not sufficiently carried out and the physical properties of the modified alkyd acrylic resin can be lowered. It is preferably added within the above range.

The initiator may be selected from the group consisting of AIBN (Azo bis-iso-butyronitrile), benzoyl peroxide, ditert butyl peroxide and tert-butyl perbenzoate, preferably benzoyl peroxide.

The additive may be used alone or in combination with a plasticizer, a dispersant, or a defoaming agent to change the physical properties of the resin or to impart additional physical properties. In addition, if the additive is used in the art, And can be used without limitation within a range that does not deteriorate the physical properties. In this case, the additive is preferably used in an amount of 5 to 30 parts by weight based on 100 parts by weight of the modified alkyd resin.

Such additives may be, for example, plasticizers such as NEO-T® (Aekyung Emulsification) or ECO-DEHCH® (Hanwha Chemical), and Depol CFC-165A® or BYK- May be used.

The lacquer composition of the present invention is obtained by diluting the modified alkyd acrylic resin obtained by the above-described method with dimethyl carbonate and an aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms, wherein 20 to 40% by weight of the modified alkyd acrylic resin, 22.5 to 72.5% And 7 to 50% by weight of an aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms.

Dimethyl carbonate is a VOC (Volatile Organic Compound) exempt substance notified by the Ministry of Environment, and unlike toluene and xylene, which are conventionally used as a solvent for a lacquer composition, emissions of volatile organic compounds are remarkably low, , And the health hygiene level of producers and users of lacquer products can be improved.

In addition, dimethyl carbonate has a higher flash point than other VOC-regulated exempt materials and does not cause a fire hazard and does not cause any irritating odor. It has a much higher solubility and volatility than butyl acetate, another VOC- The viscosity and physical properties of the lacquer composition can be controlled by using a small amount, and quick drying is possible, and workability can be improved.

When the amount of the dimethyl carbonate is less than 22.5 wt%, the modified alkyd acrylic resin can not be sufficiently diluted. Thus, a relatively large amount of aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms Should be used. However, in this case, there is a problem that the drying speed of the lacquer composition is slow, and it takes a long time to obtain the dried solid film after application of the lacquer composition.

On the other hand, if it exceeds 72.5% by weight, unevenness and opacity due to rapid volatilization in the initial drying step of the Lacquer composition are caused, and the function and esthetics of the dried solid film are lowered. Also, because of the high freezing point of dimethyl carbonate, there is a problem that it can not be volatilized when working in a low temperature environment such as a winter season, and it is frozen and can not be operated.

In order to solve the aforementioned problem of freezing the dimethyl carbonate, an aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms is used together with dimethyl carbonate in the lacquer composition of the present invention.

The aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms has a freezing point of about -90 DEG C to solve the freezing problem of dimethyl carbonate and has a lower volatilization rate than dimethyl carbonate, So that irregularities on the surface due to the rapid volatilization of the solvent and clouding can be prevented.

In addition, since the viscosity of the composition is lower than that of dimethyl carbonate (about 0.413 cP), the viscosity of the composition is lowered, thereby improving the applicability of the composition and enabling formation of a lacquer coat having a desired thickness.

The aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms may contain 30 to 40% by weight of methylcyclohexane, 31 to 47% by weight of methylhexane, 6 to 18% by weight of dimethylcyclopentane and 1 to 5% by weight of heptane .

Preferably, the methylhexane is a mixture of 46.2 to 66.7% by weight of 3-methylhexane and 33.3 to 53.8% by weight of 2-methylhexane, and the dimethylcyclopentane is preferably a mixture of 25 to 75% by weight of 1,2- Dimethyl-cyclopentane and 25 to 75% by weight of 1,3-dimethylcyclopentane, and the heptane is preferably n-heptane.

The aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms may be contained in the lubricant composition in an amount of 7 to 50% by weight. At this time, if it is contained in an amount of less than 7% by weight, it may be difficult to solve the problem of freezing of the dimethyl carbonate in a low temperature environment, the problem of unevenness due to rapid volatilization, and the whitening phenomenon.

On the other hand, when it is contained in an amount of more than 50% by weight, the viscosity of the composition of the liquid composition may be excessively low to cause a problem that the liquid composition may flow down when it is applied to the substrate. Therefore, it is preferable that the weight range is included.

On the other hand, the lacquer composition may further contain not more than 40% by weight of butyl acetate.

Butylacetate is a VOC-regulated exempt material, such as dimethyl carbonate, which is environmentally friendly and has the effect of improving the hygiene level of workers and users. In addition, since the volatilization rate is about midway between the dimethyl carbonate and the aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms, the volatilization rate can be precisely controlled by adding butyl acetate.

However, when butyl acetate is insufficiently dissolved in the modified alkyd acrylic resin, the viscosity of the lactic acid composition and the drying time are increased to form a coating film which is thinner than a desired thickness to weaken the coating film or to dry Since time may be required, it is important to include the above amount.

As such butyl acetate, primary (n-type), secondary or tertiary-type butyl acetate may be used singly or in combination.

Meanwhile, another embodiment of the present invention relates to a method for producing a lacquer composition, wherein phthalic anhydride; Soybean fatty acid or rice bran oil fatty acid; glycerin; And at least one selected from the group consisting of a styrene monomer, a butyl acrylate monomer and a methyl methacrylate monomer, and a second step of mixing the modified alkyd resin and the pentaerythritol, followed by stirring to prepare a modified alkyd resin; And a third step of mixing the modified alkyd acrylic resin with dimethyl carbonate and an aliphatic saturated hydrocarbon solvent having a carbon number of 5 to 10, and a third step of mixing the modified alkyd acrylic resin with dimethyl carbonate and an aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms.

Wherein the first step comprises adding phthalic anhydride; Soybean fatty acid or rice bran oil fatty acid; glycerin; And pentaerythritol, and then raising the temperature to a temperature range of 200 to 220 ° C, a cooling step of cooling the temperature to 100 ° C or less, and a diluting step of mixing the dimethyl carbonate.

In the modified alkyd resin production step, 150 to 190 parts by weight of soybean fatty acid or rice bran fatty acid, 15 to 55 parts by weight of glycerin and 40 to 60 parts by weight of pentaerythritol may be mixed with 100 parts by weight of phthalic anhydride. At this time, it is preferable to stir at a temperature ranging from 200 to 220 ° C while stirring through nitrogen blowing, and the yield of the modified alkyd resin as a product can be increased by refluxing while keeping the temperature constant.

The method may further include the step of removing part or all of xylene by removing the water produced in the production of the modified alkyd resin by adding xylene while keeping the temperature constant and making the vacuum state when the reaction is completed . The reaction termination time can be judged when the acid value of the composition containing the modified alkyd resin is in the range of 5 to 6.

And then diluting the modified alkyd resin by adding 80 to 220 parts by weight of dimethyl carbonate by cooling to a temperature of 100 ° C or lower. The diluted modified alkyd resin may have a Gardner viscosity D to H at room temperature desirable.

Next, in the second step, 40 to 150 parts by weight of dimethyl carbonate is further mixed based on 100 parts by weight of the modified alkyd resin obtained in the first step, and then the temperature is raised to 85 to 95 ° C .; Mixing 50 to 350 parts by weight of at least one monomer selected from the group consisting of a styrene monomer, a butyl acrylate monomer and a methyl methacrylate monomer, and reacting with the modified alkyd resin; And 31 to 160 parts by weight of dimethyl carbonate, and further maintaining the mixture for a predetermined period of time.

The step of mixing 50 to 350 parts by weight of the monomer with the modified alkyd resin comprises reacting 50 to 350 parts by weight of at least one monomer selected from the group consisting of styrene monomer, butyl acrylate monomer and methyl methacrylate monomer, It is preferably carried out by dropwise addition to the modified alkyd resin for 2 to 5 hours, followed by further raising the temperature by 3 to 10 DEG C and holding for 30 minutes to 2 hours.

At this time, it is preferable to use the monomer and the initiator in an amount of 1.6 to 15 parts by weight, more preferably a mixture in which a monomer or a monomer mixture and an initiator are uniformly mixed.

The initiator may be at least one selected from the group consisting of AIBN (Azo bis iso-butyronitrile), benzoyl peroxide, ditertbutyl peroxide and tert-butyl perbenzoate.

The step of additionally mixing 31 to 160 parts by weight of the dimethyl carbonate and then maintaining the mixture for a predetermined time may be carried out by adding the entire amount of dimethyl carbonate at a time but the whole amount of the mixture of dimethyl carbonate, Or may be carried out by adding the mixture over a plurality of times, and in the case of feeding in multiple circuits, it is preferably carried out as follows.

First, 1 to 20 parts by weight of dimethyl carbonate may be added and the mixture may be maintained for 1 to 3 hours. At this time, 0.2 to 4 parts by weight of initiator may be added together. It is preferable that a mixture of dimethyl carbonate and initiator is added in a plurality of divided portions so that the reactants do not adhere to each other uniformly, and more preferably, And it is preferable to set the holding time for 5 to 20 minutes so that a sufficient reaction occurs between each turn.

Next, 0.2 to 1 part by weight of the initiator is added in two to four portions, and a holding time of 1 to 3 hours is added between the mixing times, followed by cooling slowly and further adding 15 to 70 parts by weight of dimethyl carbonate .

Thereafter, when the temperature is lowered to 80 ° C or less, the mixture may be further mixed with 15 to 70 parts by weight of dimethyl carbonate to dilute the mixture. In this case, 5 to 30 parts by weight of the additive may be further mixed.

The additive is used for changing the physical properties of the resin or for imparting additional physical properties. The above-mentioned additives may be used, but not limited thereto, and any additive used in the technical field for improving the performance of the lacquer Available.

Meanwhile, in the third step, 20 to 40 wt% of the modified alkyd acrylic resin prepared according to the above-mentioned method, 22.5 to 72.5 wt% of dimethyl carbonate, and 7 to 50 wt% of the aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms And then mixing the modified alkyd acrylic resin with dimethyl carbonate and an aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms.

Dimethyl carbonate is exempted from VOC (Volatile Organic Compound) exemption substance notified by the Ministry of Environment. Unlike toluene and xylene, which are used as solvents for existing lacquer compositions, emissions of volatile organic compounds are remarkably low, Can be improved.

In addition, unlike acetone, which is exempted from other VOC regulations, it has a high flash point and does not cause a fire hazard and does not cause any irritating odor. It has a much higher solubility and volatility than butyl acetate, another VOC- Can be used to control the viscosity and physical properties of the lacquer composition, and has the advantage of quick drying.

However, when dimethyl carbonate is used alone as a solvent, problems of unevenness and whitening of a coating film due to a rapid volatilization rate may occur, and a freezing problem may occur in a low temperature environment due to a high freezing point.

This problem can be solved by using an aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms together with dimethyl carbonate within the above-mentioned weight range.

The aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms preferably includes 30 to 40% by weight of methylcyclohexane, 31 to 47% by weight of methylhexane, 6 to 18% by weight of dimethylcyclopentane, and 1 to 5% by weight of heptane desirable.

Preferably, the methylhexane is a mixture of 46.2 to 66.7% by weight of 3-methylhexane and 33.3 to 53.8% by weight of 2-methylhexane, and the dimethylcyclopentane is preferably a mixture of 25 to 75% by weight of 1,2- Dimethyl-cyclopentane and 25 to 75% by weight of 1,3-dimethylcyclopentane, and the heptane is preferably n-heptane.

As described above, as the solvent for diluting the modified alkyd acrylic resin in the third step, dimethyl carbonate and aliphatic saturated hydrocarbon solvents having 5 to 10 carbon atoms may be used. These two types of solvents can be used to impart a desired viscosity and drying time to the lacquer composition of the present invention. However, by further including butyl acetate, this property can be adjusted more precisely and easily, and VOC emissions Can be reduced.

As the butyl acetate, primary type (n-type), secondary type or tertiary type butyl acetate may be used singly or in combination, preferably not more than 40% by weight of the total lacquer composition. If it exceeds the above weight range, the viscosity and the drying time of the lacquer composition are excessively increased, and a coating film thinner than the desired thickness is formed to weaken the coating film or require a drying time that is not usable on the spot , It is important that it is included in the above-mentioned amount.

Hereinafter, the lacquer composition according to one embodiment of the present invention will be described, and the specific actions and effects of the present invention will be described. However, it should be understood that the present invention is not limited thereto.

[Manufacturing Example]

736 g of soybean fatty acid, 140 g of glycerin, 451 g of phthalic anhydride and 229 g of pentaerythritol were added to the reactor, stirred under nitrogen blowing, and then heated to a temperature of 210 캜 to prepare a modified alkyd resin. 15 g of xylene was then added and refluxed to conduct dehydration. When the acid value reached the range of 5 to 6, the reactor was evacuated to recover the maximum amount of xylene, and the reactor was cooled. When the temperature of the reactor dropped below 100 ° C, 490 g of dimethyl carbonate was added and stirred to dilute the modified alkyd resin.

After 1930 g of dimethyl carbonate was added to the reactor and the temperature was raised to 95 ° C, 3,442 g of monomer and 126 g of benzoyl peroxide were added dropwise to the reactor for about 3 hours, and the temperature was maintained for 1 hour at the completion of the dropwise addition. As the monomers, styrene monomers, butyl acrylate monomers or methyl methacrylate monomers may be used alone or in combination, but styrene monomers are used singly in the production examples.

Then, a mixture of 13 g of benzoyl peroxide and 246 g of dimethyl carbonate was added to the reactor in four portions at intervals of 10 minutes, and the reaction was continued at the temperature for 1 hour and 30 minutes. 4 g of benzoyl peroxide was added again twice at intervals of one and a half hours, the temperature was maintained for 2 hours, and the synthesis reaction of the modified alkyd acrylic resin was completed.

Next, 860 g of dimethyl carbonate was added to the reactor, and 283 g of an additive such as a plasticizer and a defoaming agent and 1072 g of dimethyl carbonate were added thereto when the temperature was lowered to 80 ° C or lower, and the mixture was stirred to obtain a modified alkyd acrylic resin diluted with dimethyl carbonate .

Then, dimethyl carbonate and an aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms were further added to the reactor and stirred to obtain the lacquer compositions of Experiments 1 to 18 having the compositions shown in Table 1 below.

In this case, the aliphatic saturated hydrocarbon solvent having the carbon number of 5 to 10 was prepared by mixing 38 wt% of methylcyclohexane, 23 wt% of 3-methylhexane, 19 wt% of 2-methylhexane, 8 wt% of 1,2- A solvent containing 8% by weight of 3-dimethylcyclopentane and 4% by weight of n-heptane was used.

division Modified alkyd
Acrylic resin dimethyl
Carbonate Having 5 to 10 carbon atoms
Aliphatic saturation
Hydrocarbon solvent Butyl
acetate Experimental Example 1 29.8 20.9 49.3 0.0 Experimental Example 2 29.8 22.0 48.2 0.0 Experimental Example 3 29.8 22.7 47.5 0.0 Experimental Example 4 29.8 49.5 20.7 0.0 Experimental Example 5 20.7 71.8 7.5 0.0 Experimental Example 6 20.2 72.8 7.0 0.0 Experimental Example 7 20.2 73.8 6.0 0.0 Experimental Example 8 22.5 71.0 6.5 0.0 Experimental Example 9 22.5 70.3 7.2 0.0 Experimental Example 10 22.5 55.3 22.2 0.0 Experimental Example 11 22.5 29.1 49.4 0.0 Experimental Example 12 22.5 26.5 51.0 0.0 Experimental Example 13 21.5 22.8 55.7 0.0 Experimental Example 14 28.8 33.5 22.1 15.6 Experimental Example 15 23.5 33.5 14.3 28.7 Experimental Example 16 23.5 29.5 7.5 39.5 Experimental Example 17 23.5 28.7 7.5 40.3 Experimental Example 18 23.5 24.0 7.5 45.0

(Unit: wt%)

[Example 1]

Tests for solubility of the lacquer compositions prepared in Experimental Examples 1 to 18, the presence or absence of opacity formation on the surface of the dried coating film, the drying time, pinhole, viscosity, adhesion, corrosion resistance and VOC detection were carried out in the following manner, Respectively.

Solubility measurement

The lacquer compositions of Experimental Examples 1 to 18 prepared in Preparation Examples were visually observed for the formation of sediments or agglomerates, and the solubility was judged according to the following evaluation criteria. When no sediment and agglomerate are formed at all, it can be seen that the solubility is excellent. When the solubility is excellent, it is possible to form a coating film having uniform thickness, durability and corrosion resistance, so that the solubility of the lacquer composition is preferably excellent.

⊚: no sediment or agglomerate was formed (excellent)

○: no sediment or aggregate was formed, but viscosity increased somewhat (good)

X: Sediment or aggregate formed (poor)

Presence or absence of whiteness  Confirm

A steel plate (dimension: 15 x 7 x 0.23 cm) was prepared and coated with the lacquer compositions of Experimental Examples 1 to 18 on a steel sheet using an air spray gun so that the average film thickness of the coated film was 20 m, And dried in a thermostatic chamber at a relative humidity of 50% for 1 week to prepare a test piece. Thereafter, when the surface of the prepared test piece is observed, X is indicated when no whitening phenomenon occurs, and when the whitening phenomenon has occurred, it is indicated as O. In case whitening occurs, the lacquer coating may peel off from the base material, Is preferably not generated.

Drying time measurement

When the lacquer compositions of Experimental Examples 1 to 18 were applied to the steel sheet, the initial time (tack-free drying time) when the surface of the coated film was lightly pressed with the fingers was evaluated. If the drying time is shorter than 240 seconds, it is preferable that the drying time is longer than 240 seconds. If the drying time is longer than 240 seconds, the drying time required for final drying may be longer.

Viscosity measurement

Viscosity was measured according to ISO ASTM D 4214 standard using Ford cup # 4 in a constant temperature environment at 25 ° C. Specifically, an indirect viscosity value representing the time until the lacquer composition was completely discharged through the hole at the lower end of the Ford cup # 4 after filling the lacquer composition of Experiments 1 to 18 into Ford cup # 4 was used. The measured viscosity value is preferably in the range of 13 to 14 seconds, and if it is out of the above range, it is difficult to form a coating film having a desired thickness and workability may be deteriorated.

Attachment Cross cut measurement

A 5x5 cm steel plate was prepared and applied to one side of the steel sheet, respectively, and then dried naturally for 1 hour to form a lacquer film. Thereafter, the lacquer film was cut at intervals of 2 mm in a grid pattern of 10 rows x 10 columns, desorption experiments were carried out using Cellophane Tape (registered trademark), and evaluated according to the following evaluation criteria. At this time, when the number of pieces of detacked lacquer film is 9 or less, it can be judged that the adhesive property is excellent.

◎: When the detached lacquer film fragments are 0 to 9 (excellent)

○: 10 to 29 pieces of detached lacquer coating (good)

Corrosion resistance measurement

The salt spray test of the lacquer compositions of Experimental Examples 1 to 18 was carried out according to KS D9502, and the corrosion resistance was evaluated according to the rating number (RN) method.

◎: When the rating number is 10 (excellent)

○: When the rating number is 9 to 9.8 (Good)

VOC  Measured amount of measurement

The VOC detection amount was measured in accordance with KS M ISO 11890-2: 2007 in the joint laboratory habits of Pukyong National University with the Korea Institute of Construction & Living Environment Test.

Cold freezing test

The lacquer compositions of Experimental Examples 1 to 18 were exposed to a low-temperature environment at a temperature of -10 占 폚. After 1 hour, when the lacquer composition was frozen to show no fluidity, the composition was frozen. Table 2 shows the results. At this time, when the lacquer composition is frozen, it means that work in a low-temperature environment is impossible, and therefore, it is preferable that the lacquer composition is not frozen.

division Solubility Presence or absence of whiteness Drying time
(second) Viscosity
(second)* Attachment Corrosion resistance VOC detection
(g / L) Whether to freeze Experimental Example 1 X X 270 13.66 ◎ ◎ 100.69 X Experimental Example 2 X X 260 13.45 ◎ ◎ 98.60 X Experimental Example 3 ◎ X 210 13.40 ◎ ◎ 97.27 X Experimental Example 4 ◎ X 190 13.22 ◎ ◎ 46.35 X Experimental Example 5 ◎ X 110 13.03 ◎ ◎ 22.18 X Experimental Example 6 ◎ O 90 12.21 ◎ ◎ 21.28 O Experimental Example 7 ◎ O 80 11.53 ◎ ◎ 18.43 O Experimental Example 8 ◎ O 90 13.05 ◎ ◎ 20.67 O Experimental Example 9 ◎ X 110 13.11 ◎ ◎ 21.43 X Experimental Example 10 ◎ X 170 13.15 ◎ ◎ 49.93 X Experimental Example 11 ◎ X 230 13.45 ◎ ◎ 95.23 X Experimental Example 12 ◎ X 260 13.37 ◎ ◎ 112.94 X Experimental Example 13 ◎ X 290 13.40 ◎ ◎ 118.68 X Experimental Example 14 ◎ X 190 13.96 ◎ ◎ 45.11 X Experimental Example 15 ◎ X 200 14.13 ◎ ◎ 31.82 X Experimental Example 16 ◎ X 210 14.35 ◎ ◎ 17.90 X Experimental Example 17 O X 260 15.43 ○ ○ 17.55 X Experimental Example 18 O X 280 16.71 ○ ○ 16.41 X

 (*: Indirect viscosity value indicating the time until all of the lacquer composition is discharged from Ford cup # 4.)

As a result of the test, the lacquer compositions of Experimental Examples 3 to 5, 9 to 11 and 14 to 16 contained a modified alkyd acrylic resin, dimethyl carbonate and an aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms in the preferred range defined in the present invention , And is an environmentally friendly solvent having excellent solubility, drying time, viscosity, adhesion and corrosion resistance, freezing in a whitening or low temperature environment, and reduced VOC emission.

On the other hand, the lacquer compositions of Experimental Examples 1 and 2 were not completely dissolved and partly aggregated and showed poor solubility. Also, the drying time exceeded 240 seconds and the time required for the operation rapidly increased. This is because the dimethyl carbonate of Experimental Examples 1 and 2 was contained in an amount of less than 22.5 wt%, which was used in an amount insufficient to sufficiently dissolve the modified alkyd acrylic resin.

On the other hand, in the case of Experimental Examples 6 and 7, dimethyl carbonate was included in an amount exceeding 72.5% by weight, and it was confirmed that whitening occurred on the surface of the coating film coated with the lacquer composition due to an excessively short drying time. In addition, in the case of Experimental Examples 6 and 7, it was shown that the lacquer composition was frozen in a low-temperature environment, and although it was not included in the results of Table 2, it was confirmed that a part of the lacquer composition flowed down from the interface of the coating due to low viscosity .

Therefore, in order to prevent the above-described problems from occurring, it has been experimentally confirmed that dimethyl carbonate is preferably contained in a composition ratio of 22.5 to 72.5% by weight based on the total lacquer composition.

On the other hand, in Experiment 8, the content of the aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms was insufficient, and it was frozen in a low temperature environment, and the rapid volatilization rate due to dimethyl carbonate could not be sufficiently canceled.

 On the other hand, in the case of Experimental Examples 12 and 13, it was found that the use of an excessive amount of aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms resulted in a drying time of a level which was practically difficult to use. This is considered to be a problem because the drying rate of the aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms is very slow.

Therefore, in order to obtain a coating film having excellent physical properties without causing an excessive increase in freezing and drying time in a low-temperature environment, an aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms in a range of about 7 to 50% by weight of the total Lacquer composition is used .

On the other hand, according to the experimental results of Experimental Examples 14 to 16, it can be seen that as the amount of butyl acetate added to the lacquer composition is increased, the amount of VOC emissions is reduced. In the case of using the same amount of aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms , The addition of butyl acetate showed a further reduction in VOC emissions.

However, as in Examples 17 and 18, when the content of butyl acetate exceeds 40% by weight, there is a problem that the solubility is lowered and the viscosity is increased and the adhesion and the corrosion resistance are lowered. Therefore, .

[Example 2]

In order to confirm the effect of addition of acetone, which is a conventionally used solvent, to the lacquer composition of the present invention, 29.8 wt% of modified alkyd acrylic resin, 23.5 wt% of dimethyl carbonate, 12.2 wt% of aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms, A lacquer composition of Experimental Example 19 having a composition of 14.5 wt% butyl acetate and 20.0 wt% acetone was prepared. Thereafter, in the same manner as in Example 1, the presence / absence of whitening, the drying time, and the viscosity were measured, and the results are shown in Table 3.

division Presence or absence of whiteness Drying time (sec) Viscosity (sec) Experimental Example 19 O 70 10.38

As a result of the experiment, it was confirmed that in the case of Experimental Example 19, the drying time was excessively shortened due to the addition of highly volatile acetone, and the whitening phenomenon appeared on the surface of the coating film formed by applying the lacquer composition. Further, it was difficult to form a coating film having a desired thickness due to a remarkable decrease in viscosity. Although not shown in the results of Table 3, flow-down of the liquid composition was observed at the interface of the coating film.

When acetone is additionally contained in the lacquer composition of the present invention, it is expected that the emission of VOC will be reduced. However, since the workability and the surface quality are lowered, it is preferable that the lacquer composition of the present invention does not contain acetone.

Accordingly, the lacquer composition of the present invention contains 20 to 40% by weight of modified alkyd acrylic resin, 22.5 to 72.5% by weight of dimethyl carbonate, and 7 to 50% by weight of an aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms, Quality, adhesiveness, corrosion resistance and workability, as well as release a small amount of VOC compared to conventional lacquer compositions, thereby improving the hygiene environment of the operator or the user.

Claims (8)

In the lacquer composition,
Wherein the Lacquer composition comprises 20 to 40% by weight of a modified alkyd acrylic resin, 22.5 to 72.5% by weight of dimethyl carbonate, and 7 to 50% by weight of an aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms,
The aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms includes methyl cyclohexane, methyl hexane, dimethyl cyclopentane, and heptane,
The modified alkyd acrylic resin is obtained by copolymerizing a modified alkyd resin with at least one monomer selected from the group consisting of a styrene monomer, a butyl acrylate monomer, and a methyl methacrylate monomer, , ≪ / RTI >
The modified alkyd resin may be selected from the group consisting of phthalic anhydride; Soybean fatty acid or rice bran fatty acid; Glycerin; And pentaerythritol. ≪ RTI ID = 0.0 > 1. < / RTI >
delete delete The method according to claim 1,
The above-
And further comprising butyl acetate in a range of not more than 40% by weight, based on the total weight of the composition.
Phthalic anhydride; Soybean fatty acid or rice bran fatty acid; Glycerin; And pentaerythritol, followed by stirring to prepare a modified alkyd resin,
At least one monomer selected from the group consisting of a styrene monomer, a butylacrylate monomer and a methyl methacrylate monomer is reacted with the modified alkyd resin to form a modified A second step of producing an alkyd acrylic resin, and
A modified alkyd acrylic resin, dimethyl carbonate (20 to 40 wt.%), A modified alkyd acrylic resin (22 to 72.5 wt.%) And an aliphatic saturated hydrocarbon solvent having a carbon number of 5 to 10 (Dimethyl carbonate) solvent and an aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms,
Wherein the aliphatic saturated hydrocarbon solvent having 5 to 10 carbon atoms is selected from the group consisting of Methyl Cyclohexane, Methyl Hexane, Dimethyl Cyclopentane and Heptane. Gt;
6. The method of claim 5,
In the first step,
100 parts by weight of phthalic anhydride; 150 to 190 parts by weight of soybean fatty acid or rice bran oil fatty acid; 15 to 55 parts by weight of glycerin; And 40 to 60 parts by weight of pentaerythritol, and then heating the mixture to a temperature ranging from 200 to 220 ° C .;
A cooling step of cooling the temperature to 100 DEG C or lower; And
And a diluting step of adding dimethyl carbonate,
Adding xylene between the step of producing the modified alkyd resin and the step of cooling to dehydrate and recovering the xylene when the acid value reaches the range of 5 to 6, Including,
The second step comprises:
Further mixing 40 to 150 parts by weight of dimethyl carbonate with 100 parts by weight of the modified alkyd resin obtained in the first step and then raising the temperature to 85 to 95 ° C;
50 to 350 parts by weight of at least one monomer selected from the group consisting of a styrene monomer, a butylacrylate monomer and a methyl methacrylate monomer is mixed with the modified alkyd resin ; And
31 to 160 parts by weight of dimethyl carbonate is further added, and the mixture is maintained for a predetermined time.
delete 6. The method of claim 5,
In the third step,
By weight, and further adding butylacetate in an amount of not more than 40% by weight based on the total weight of the composition.