KR102557201B1 - Curable composition - Google Patents

Abstract

This application is directed to curable compositions. The present application, as a curable composition that can be applied to an in-mold coating process, can provide a curable composition that is excellent in impact resistance, scratch resistance, light resistance, etc., does not emit harmful substances, and can be rapidly cured.

Description

Curable composition {CURABLE COMPOSITION}

This application relates to a curable composition.

Molded articles having a surface coating, for example, products made of wood, wood-based material, plastic or fiber composite material, etc. Applied to various uses. A typical use is in the automotive industry, and for example, the products described above can be mainly used as interior materials such as interior trims of automobiles.

Physical properties such as transparency, adhesion, scratch resistance, or durability may be typically required for a painting material applied as a surface coating to such a product. That is, the coating layer formed on the surface of the molded article is required to be transparent without haze after curing, adhesive strength capable of well adhering to the molded article, scratch resistance capable of protecting the molded article from external stimuli, and heat resistance However, it is necessary to ensure durability by being excellent in light resistance and the like.

In addition, the materials should not emit harmful substances such as volatile organic compounds (VOCs) during or after the formation of the coating layer.

As a method of manufacturing a surface-coated molded article, a so-called in-mold coating process (IMC) is known. In this process, the production of the molded part in the mold and the coating of the surface of the molded part are performed in a single process.

In the case of a material applied to such a process, it must have an appropriate viscosity so that it can be easily sprayed, the coated material must be cured quickly, and after curing, it must be easily peeled from the mold (releasability, demolding), and the external It must have high hardness to be protected from impact.

This application is directed to curable compositions. In the present application, to provide a curable composition that is easily sprayed, rapidly cured, easily peeled from the mold after curing, and has sufficient hardness to be protected from external impact so that it can be suitably applied to the in-mold coating process have one purpose

This application is directed to curable compositions. In one example, the curable composition may be used as a painting material in an in-mold coating (IMC) process.

In the in-mold coating process, the surface coating of the molded article is performed in the mold. In this case, a coating material, usually liquid, is sprayed or injected between the inner wall of the mold cavity and the surface of the molded product to be coated on the surface of the molded product and cured to form a paint.

The curable composition of the present application is excellent in transparency, adhesion, scratch resistance and impact resistance, and can form a cured product that does not release harmful substances in a short time. In addition, the curable composition of the present application can be effectively applied as a coating material in a coating process in a mold because of excellent releasability (release) from a mold.

The curable composition of the present application may be a room temperature curing type, a thermosetting type or a moisture curing type composition. In the above, the room temperature curable composition may refer to a composition in which the curing may proceed at room temperature. Further, in the above, the moisture-curable composition may refer to a composition in which curing proceeds in the presence of moisture, and the thermosetting composition may refer to a composition in which curing proceeds under the application of heat.

In this application, the term “room temperature” may mean a natural temperature that is not heated or cooled. For example, room temperature may refer to any temperature in the range of about 10 to 30 °C, or about 25 °C or 23 °C.

In this application, the term "atmospheric pressure" is a pressure when not particularly reduced or increased, and may mean about 1 atm, which is usually equal to atmospheric pressure.

Among the physical properties mentioned in this specification, if the measured temperature and / or pressure affects the physical properties, the corresponding physical properties refer to the physical properties measured at room temperature and / or atmospheric pressure, unless otherwise specifically defined.

In one example, the curable composition of the present application may include a polyol whose hydroxyl value, hydroxyl equivalent (hydroxyl equivalent), and content are appropriately adjusted so that the physical properties of the composition desired in the present application can be secured.

In this application, the term "polyol" means a compound containing at least two hydroxyl groups.

In this application, the term “hydroxyl value” may refer to the number of mg of potassium hydroxide (KOH) required to neutralize acetic acid produced when 1 g of polyol is acetylated and then the acetylated polyol is hydrolyzed. In addition, a method for measuring the hydroxyl value is known, and a method known in the art may be applied, for example, a method according to the standard of JIS K 155701 may be applied.

In this application, the term “hydroxy equivalent weight” may refer to the molecular weight (eg, number average molecular weight) of the polyol per number of functional groups of hydroxyl groups included in the polyol. In addition, a method for measuring the hydroxy equivalent is known, and a general measurement method known in the art may be applied. For example, the hydroxy equivalent may be a value obtained by dividing the molecular weight of the polyol by the number of functional groups of the hydroxy group of the polyol.

In one example, the curable composition of the present application may include at least a first polyol and a second polyol having different hydroxyl values.

In one example, the hydroxyl value of the first polyol may be 400 mKOH/g or more. In another example, the value is 410 mgKOH / g or more, 420 mgKOH / g or more, 430 mgKOH / g or more, 440 mgKOH / g or more, 450 mgKOH / g or more, 460 mgKOH / g or more, 470 mgKOH / g or more, 480 mgKOH/g or more, 490 mgKOH/g or more, 500 mgKOH/g or more, 510 mgKOH/g or more, 520 mgKOH/g or more, 530 mgKOH/g or more, 540 mgKOH/g or more, or 550 mgKOH/g or more, 700 mgKOH/g or less, 690 mgKOH/g or less, 680 mgKOH/g or less, 670 mgKOH/g or less, 660 mgKOH/g or less, 650 mgKOH/g or less, 640 mgKOH/g or less, 630 mgKOH/g or less, 620 mgKOH /g or less, 610 mgKOH/g or less, 600 mgKOH/g or less, 590 mgKOH/g or less, 580 mgKOH/g or less, or 570 mgKOH/g or less.

In one example, the second polyol may have a lower hydroxyl value than the first polyol. For example, the hydroxyl value of the second polyol may be less than 400 mKOH/g.

In another example, the hydroxyl value of the second polyol may be in the range of 110 to 390 mgKOH/g. In another example, the value may be 120 mgKOH/g or more, 130 mgKOH/g or more, 140 mgKOH/g or more, 150 mgKOH/g or more or 160 mgKOH/g or more, 380 mgKOH/g or less, 370 mgKOH/g 360 mgKOH/g or less, 350 mgKOH/g or less, 340 mgKOH/g or less, 330 mgKOH/g or less, 320 mgKOH/g or less, 310 mgKOH/g or less, 300 mgKOH/g or less, 290 mgKOH/g or less, 280 mgKOH/g or less, 270 mgKOH/g or less, 260 mgKOH/g or less, 250 mgKOH/g or less, 240 mgKOH/g or less, or 230 mgKOH/g or less.

From the viewpoint of improving the coating properties of the curable composition, the OH equivalent of the second polyol may also be adjusted.

In one example, each of the hydroxy equivalents of the first polyol and the second polyol may be 400 or less. Also, the hydroxy equivalent weight of the first polyol and the second polyol may be different from each other, and for example, the hydroxy equivalent weight of the first polyol may be lower than that of the second polyol.

For example, the hydroxyl equivalent of the first polyol may be 400 or less. In another example, the equivalent weight may be 350 or less, 300 or less, 250 or less, 200 or less, 150 or less, 140 or less, 130 or less, 120 or less, or 110 or less, and the lower limit is not particularly limited, but, for example, It may be 40 or more, 50 or more, 60 or more, 70 or more, 80 or more, or 90 or more.

In another example, the OH equivalent of the second polyol may be 400 or less. In another example, the equivalent weight may be 390 or less, 380 or less, 370 or less, 360 or less, 350 or less, or 340 or less, and the lower limit is not particularly limited, but is, for example, 100 or more, 110 or more, 120 or more, 130 or more, 140 or more, 150 or more, 160 or more, 170 or more, 180 or more, 190 or more, 200 or more, 210 or more, 220 or more, 230 or more, 240 or more, or 250 or more.

In one example, the curable composition may include the first polyol in an amount of 60% by weight or more. The ratio, in another example, may be about 65% by weight or more, or about 70% by weight or more, and the upper limit is not particularly limited, for example, less than 100% by weight, 95% by weight or less, 90% by weight or less , 85 wt% or less, or 80 wt% or less. Within the range of the ratio of the first polyol, the curable composition can be rapidly cured and has high hardness upon curing, so it can be more suitable for application to a coating in a mold.

The curable composition of the present application may further include other types of polyols in addition to the above two types of polyols in order to secure physical properties suitable for in-mold coating.

In one example, polyether polyol, polyester polyol, polycarbonate polyol, or polybutadiene polyol may be used as the first or second polyol.

In the above, polyalkylene glycol having an alkylene unit having 1 to 4 carbon atoms, such as polypropylene glycol or polyethylene glycol, can be used as the polyether polyol. Further, as the polyester polyol, a polycondensation polyester polyol such as an adipate polyester polyol or a ring-opening addition polymerization polyester polyol such as a lactone polyester polyol may be used.

In one example, from the viewpoint of preparing a curable composition having properties of the curable composition desired in the present application, for example, being curable in a short time or having a low viscosity at a high temperature, as the polyol, an amorphous polyol or A sufficiently low crystallinity polyol may be used.

In the present application, the term "amorphous" may mean a case in which a crystallization temperature (T _C ) and a melting temperature (T _m ) are not observed in differential scanning calorimetry (DSC) analysis. At this time, the DSC analysis may be performed within the range of -80 ℃ to 60 ℃ at a rate of 10 ℃ / min. For example, the DSC analysis can be measured by raising the temperature from 25 °C to 60 °C at the above rate, then decreasing the temperature to -80 °C, and raising the temperature to 60 °C again. In addition, the sufficiently low crystallinity in the above means that the melting point (T _m ) observed in the DSC analysis is about 20 ℃ or less, about 15 ℃ or less, about 10 ℃ or less, about 5 ℃ or less, about 0 ℃ or less, about It means the case of -5 ℃ or less, about -10 ℃ or less, or about -20 ℃ or less. The lower limit of the melting point is not particularly limited, but, for example, the melting point may be about -80 °C or higher, about -75 °C or higher, or about -70 °C or higher.

A polyester polyol may be used as the amorphous or sufficiently low crystallinity polyol. In addition, among polyester polyols, polycondensation-based (carboxylic acid-based) polyester polyols or ring-opening addition polymerization-based (caprolactone-based) polyols, specifically polycondensation-based polyester polyols, have curing properties suitable for the above-mentioned purpose of the curable composition of the present application. can be effectively fulfilled.

In general, a carboxylic acid-based polyol can be formed by reacting a component containing a dicarboxylic acid and a polyhydric polyol (eg, diol or triol). In addition, the caprolactone-based polyol can be formed by reacting a component including caprolactone and a polyhydric polyol (eg, diol or triol). That is, the carboxylic acid-based polyol may include a polyhydric polyol unit and a dicarboxylic acid unit. In addition, the caprolactone-based polyol may include a polyhydric polyol unit and a caprolactone unit. At this time, it is possible to configure a polyol that satisfies the above-described physical properties through control of the type and ratio of each component.

In the above, the unit of a certain compound means a state in which the compound undergoes a polymerization reaction to form a polymer and then forms the main chain and/or side chain of the polymer.

In the above, the dicarboxylic acid unit is a unit formed by a polycondensation reaction of a dicarboxylic acid with a polyhydric polyol, and the polyhydric polyol unit is a unit formed by a polymerization reaction of the corresponding polyhydric polyol with a dicarboxylic acid or caprolactone.

That is, when the hydroxyl group of the polyhydric polyol and the carboxyl group of the dicarboxylic acid react, water (H ₂ O) molecules are desorbed by the condensation reaction, and an ester bond may be formed.

In one example, the dicarboxylic acid unit may be an aliphatic dicarboxylic acid unit or an aromatic dicarboxylic acid unit, and considering the glass transition temperature of the coated curable composition, an aliphatic dicarboxylic acid unit may be appropriate.

As the aromatic dicarboxylic acid unit, a phthalic acid unit, an isophthalic acid unit, a terephthalic acid unit, a trimeltric acid unit, a tetrahydrophthalic acid unit, a hexahydrophthalic acid unit, or a tetrachlorophthalic acid unit can be used.

Examples of the aliphatic dicarboxylic acid units include oxalic acid units, adipic acid units, azelaic acid units, sebacic acid units, succinic acid units, malic acid units, glutaric acid units, malonic acid units, pimelic acid units, suberic acid units, 2, 2-dimethylsuccinic acid units, 3,3-dimethylglutaric acid units, 2,2-dimethylglutaric acid units, maleic acid units, fumaric acid units, itaconic acid units, or fatty acid units may be used, but among them, adip It may be appropriate to use acid units.

In one example, an aliphatic polyhydric polyol unit or an aromatic polyhydric polyol unit may be used as the polyhydric polyol unit, and it may be appropriate to use an aliphatic polyhydric polyol unit when suitability for an in-mold coating process is considered. Specifically, as the polyhydric polyol unit, an aliphatic polyhydric polyol, especially when the number of carbon atoms in the main chain of the polyol is odd (for example, 3 or more or 5 or more, 7 or less, or 5 or less), it has a symmetrical structure. may be appropriate In addition, when a polyol unit having a branched chain and exhibiting amorphousness is used as the aliphatic polyhydric polyol unit, the glass transition temperature of the polyol can be reduced, thereby mitigating aggregation between molecules, and a soft polyester polyol. can be obtained. In addition, in the case of using the polyol unit exhibiting amorphousness, handling is easy because the curable composition exists in a liquid state even at room temperature, and light resistance may be excellent because of high transparency.

The aliphatic polyhydric polyol units include ethylene glycol units, propylene glycol units, 1,2-butylene glycol units, 2,3-butylene glycol units, 1,3-propanediol units, 1,3-butanediol units, 1, 4-butanediol unit, 2-methyl-2,4-pentanediol unit, 1,6-hexanediol unit, neopentylglycol unit, 1,2-ethylhexyldiol unit, 1,5-pentanediol unit, 1,10 - A decanediol unit, a 1,3-cyclohexanedimethanol unit, a 1,4-cyclohexanedimethanol unit, a glycerin unit, or a trimethylolpropane unit can be used.

In one example, when polyester polyol is used as the first polyol and the second polyol, types of aliphatic polyhydric polyol units constituting the corresponding polyol may be different from each other. Specifically, as the first polyol, a carboxylic acid-based polyester polyol including at least one aliphatic polyhydric polyol unit selected from a hexanediol unit and a trimethylolpropane unit may be used. In addition, as the second polyol, a carboxylic acid-based polyester polyol including at least one aliphatic polyhydric polyol unit selected from a trimethylolpropane unit and a methylpentadiol unit may be used.

In another example, the number of functional groups (hydroxy groups) in the polyhydric polyol unit may be 2 or more, or 3 or more, and may be 6 or less, 5 or less, or 4 or less.

In one example, the molecular weight of the polyol may also be adjusted so that physical properties of the curable composition desired in the present application may be secured. For example, the number average molecular weight of the polyol (first polyol or second polyol) may be in the range of 500 to 3000 g/mol.

In this application, the term number average molecular weight may refer to a value in terms of standard polystyrene measured by GPC (Gel Permeation Chromatograph) unless otherwise specified.

In the curable composition, a weight ratio between the first polyol and the second polyol may also be adjusted from the viewpoint of improving physical properties suitable for in-mold coating. In one example, the curable composition may include the second polyol in an amount of 10 to 60 parts by weight based on 100 parts by weight of the first polyol. In another example, the ratio may be 15 parts by weight or more, 20 parts by weight or more, or 25 parts by weight or more, and may be 55 parts by weight or less, 50 parts by weight or less, 45 parts by weight or less, or 43 parts by weight or less.

The curable composition may further include necessary additives depending on the purpose. The additive may be, for example, a known additive such as a UV stabilizer, a flame retardant, an antioxidant, a thixotropy imparting agent, or a dispersing agent.

For example, the curable composition may further include a catalyst capable of accelerating the curing reaction. As the catalyst, any known catalyst known to be able to promote the urethane reaction may be applied, and for example, a metal catalyst or an amine catalyst may be applied.

In the above, as the metal catalyst, an organic metal compound such as an organic tin compound, an organic bismuth compound, an organic titanium compound, an organic zirconium compound, or an organic aluminum compound may be applied. Specifically, metal catalysts include dibutyltin dilaurate (DBTL), stannous octoacte, dibutyltin diacetate, dibutyltin dimercaptide, and the like. The same dialkyltin dicarboxylates can be applied.

In addition, as an amine catalyst, 1,4-diazabicyclo [2,2,2] octane (1,4-diazabicyclo [2,2,2] octane), bis (2-dimethylaminoethyl) ether (bis ( 2-dimethylaminoethyl)ether), trimethylaminoethylethanolamine, N,N,N',N',N''-pentamethyldiethylenetriamine (N,N,N',N',N'' -pentamethyldiethylenetriamine), N,N'-dimethylethanolamine (N,N'-dimethylethanolamine), dimethylaminopropylamine, N-ethylmorpholine, N,N-dimethylaminoethylmorpholine ( Tertiary amines such as N,N-dimethylaminoethylmorpholine, N,N-dimethylcyclohexylamine, or 2-methyl-2-azanorbonrnane This may be applied, but is not limited thereto.

In one example, the curable composition may include a catalyst in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the total of the polyols (eg, the first polyol and the second polyol) included in the curable composition. there is. In another example, the ratio is 0.5 parts by weight or more, 1 part by weight or more, 1.5 parts by weight or more, 2 parts by weight or more, 2.5 parts by weight or more, 3 parts by weight or more, 3.5 parts by weight or more, 4 parts by weight or more, 4.5 parts by weight or more. or 5 parts by weight or more, 9.5 parts by weight or less, 9 parts by weight or less, 8.5 parts by weight or less, 8 parts by weight or less, 7.5 parts by weight or less, 7 parts by weight or less, 6.5 parts by weight or less, 6 parts by weight or less, or 5.5 parts by weight or less. It may be less than parts by weight.

This application also relates to two component curable compositions. It may be more advantageous to apply a two-component curable composition so that it can be more suitably applied to the above-described in-mold coating process.

The two-component curable composition may include a main composition part and a curing agent composition part. In addition, the two-component curable composition may use the above-described curable composition as a main composition part. That is, the two-component curable composition of the present application may include at least a subject composition part and a curing agent composition part, which are the curable compositions described above.

In the two-component curable composition, curing may be progressed by a reaction between a subject composition part and a curing agent composition part. Accordingly, the subject composition part and the curing agent composition part may be in contact with each other or separated from each other. When the curable composition is in a separate state, during the process, the subject composition part and the curing agent composition part are mixed, and a curing reaction may proceed accordingly.

The curing agent composition part included in the two-component curable composition contains at least a polyisocyanate compound as a basic component.

In this application, the term "polyisocyanate compound" may mean a compound having at least two isocyanate groups.

The polyisocyanate compound of the curing agent composition part may be appropriately selected so as to secure the physical properties of the two-component curable composition desired in the present application, and if necessary, polyisocyanate compounds having different physical properties or different types are used as described above. It may be included in the curing agent composition part.

In one example, an aromatic polyisocyanate compound or an aliphatic polyisocyanate compound may be used as the polyisocyanate compound, but it may be appropriate to use an aliphatic polyisocyanate compound in terms of securing light resistance of the two-component curable composition.

In one example, as the polyisocyanate compound, a compound obtained by reacting at least one isocyanate compound of the aromatic polyisocyanate and the aliphatic polyisocyanate with a polyol may be used, and trimethylolpropane or the like may be used as the polyol.

In one example, the aromatic polyisocyanate compound includes tolylene diisocyanate, diphenylmethane diisocyanate, phenylene diisocyanate, polyethylenephenylene polyisocyanate, xylene diisocyanate, tetramethylxylene diisocyanate, trizine diisocyanate, Naphthalene diisocyanate or triphenylmethane triisocyanate or the like can be used.

In one example, the aliphatic polyisocyanate compound includes hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, lysine diisocyanate, norbornane diisocyanate methyl, ethylene diisocyanate, propylene diisocyanate, tetramethylene diisocyanate, transcyclohexane -1,4-diisocyanate, isophorone diisocyanate, isoborone diisocyanate, bis (isocyanate methyl) cyclohexane diisocyanate or dicyclohexylmethane diisocyanate can be used, and in order to be suitably applied to the coating process in the mold Hexamethylene diisocyanate or its reaction product with a polyol may be suitable.

In one example, in order to secure suitable coating properties of the two-component curable composition, the molecular weight of the polyisocyanate compound included in the curing agent composition part may also be adjusted. For example, the molecular weight of the polyisocyanate compound may be in the range of 500 to 5000 g/mol.

In order to exhibit suitable coating properties of the two-component curable composition, for example, fast curing speed and low viscosity at high temperature, the composition of the curing agent composition part may also be appropriately adjusted.

In one example, the NCO content of the curing agent composition part may be 30% by weight or less. In another example, the content may be 29 wt% or less, 28 wt% or less, 27 wt% or less, 26 wt% or less, 25 wt% or less, 24 wt% or less, or 23.5 wt% or less, the lower limit being particularly limited. Although not necessarily, it may be, for example, 5% by weight or more, 10% by weight or more, 15% by weight or more, 17% by weight or more, 19% by weight or more, or 20% by weight or more. In the present application, the NCO content may refer to a weight ratio of an isocyanate group (-NCO) in a curing agent composition part including the polyisocyanate compound in %. When the curing agent composition part includes only the polyisocyanate compound, the NCO content of the curing agent composition part may be the same as the NCO content of the polyisocyanate compound. In addition, as a method for measuring the NCO content, a known measurement method, for example, a measurement method according to the M105-ISO 11909 standard may be applied.

In one example, the isocyanate equivalent of the curing agent composition part may be 250 or less. In another example, the equivalent may be 245 or less, 240 or less, 235 or less, 230 or less, 225 or less, 220 or less, or 215 or less, and the lower limit of the equivalent is not particularly limited, but is, for example, 100 or more, It may be 110 or more, 120 or more, 130 or more, 140 or more, 150 or more, 160 or more, 170 or more, 180 or more, or 185 or more. In the present application, the term "equivalent weight of isocyanate" may refer to the molecular weight of the polyisocyanate compound per number of functional groups of isocyanate groups included in the polyisocyanate compound. In addition, a measuring method of the isocyanate equivalent is known, and a general measuring method known in the art may be applied. In the above, when the curing agent composition part includes only the polyisocyanate compound, the isocyanate equivalent of the curing agent composition part may be the same as the isocyanate equivalent of the polyisocyanate compound.

In the curing agent composition part, the polyisocyanate compound may be included within an appropriate ratio range capable of being cured with the subject composition part. For example, when the curing agent composition part and the subject composition part are mixed, the ratio of the hydroxy equivalent of the subject composition part to the isocyanate equivalent of the curing agent composition part is a stoichiometric ratio, for example, 1:0.9 to 1:1.1, or 1:1 to 1:1.1. In addition, when the curing agent composition part is composed only of the polyisocyanate compound, the equivalent ratio of the curing agent composition part may be adjusted according to the ratio of the polyisocyanate compound.

For example, the ratio of the curing agent composition part may be 50 to 350 parts by weight based on 100 parts by weight of the total polyol included in the subject composition part. In another example, the ratio is 60 parts by weight or more, 70 parts by weight or more, 80 parts by weight or more, 90 parts by weight or more, 100 parts by weight or more, 110 parts by weight or more, 120 parts by weight or more, 130 parts by weight or more, 140 parts by weight or more. 340 parts by weight or less, 330 parts by weight or less, 320 parts by weight or less, 310 parts by weight or less, 300 parts by weight or less, 290 parts by weight or less, 280 parts by weight or less, 270 parts by weight or less, 260 parts by weight or less, 250 It may be 240 parts by weight or less, 230 parts by weight or less, 220 parts by weight or less, 210 parts by weight or less, 200 parts by weight or less, or 190 parts by weight or less. When the curing agent composition includes only the polyisocyanate compound, the ratio of the curing agent composition part may mean the ratio of the polyisocyanate compound to the main composition part.

The curing agent composition part may also further include necessary additives depending on the purpose. As described above, the additive may be, for example, a known additive such as a diluent, a polyol, a UV stabilizer, a flame retardant, an antioxidant, a thixotropy imparting agent, or a dispersing agent.

This application also relates to methods of making surface coated products. The method relates to a method for producing a surface coating product using the above-described composition as a coating material.

In one example, the manufacturing method may be an in-mold coating (IMC) process using the curable composition or the two-component curable composition as a coating material.

The method of proceeding the process is not particularly limited, and may be performed according to a method known in the art.

For example, the process may include forming a molded article within a cavity of a mold; and forming a surface coating layer by coating the composition (a curable composition or a two-component curable composition) on a surface of the molded article.

As described above, the composition of the present application is excellent in transparency, adhesion, scratch resistance, etc., can form a cured product that does not release harmful substances in a short time, and has excellent mold release (release) property. Therefore, it can be effectively applied to the process as described above.

In one example, the coating may be performed by injecting the curable composition between the inner wall of the cavity of the mold and the surface of the molded article. As a method of injecting the curable composition, a conventionally known method may be used, and for example, a spraying process, a coating process, and the like may be used.

In one example, the method of forming the molded article is not particularly limited, and for example, the molded article may be formed by injection molding a thermoplastic resin into a cavity of a mold.

In one example, coating may be performed after forming the molded article, may be performed simultaneously with forming the molded article, or may be performed before forming the molded article. For example, the composition may be coated or sprayed on one side of the mold cavity and then a base material (eg, thermoplastic resin) may be injected.

In one example, the process may be performed in such a way that a curing process is performed after coating and then the mold is removed, or a curing process is performed after removing the mold.

The type of product manufactured by the process is not particularly limited, and all types of products that can be manufactured by the in-mold coating process can be manufactured by the process, and representative examples of the product include automobile interior materials. However, it is not limited thereto.

The curable composition of the present application has an advantage in that it has excellent impact resistance, scratch resistance, light resistance, etc., and can be rapidly cured at the same time without emitting harmful substances.

Although the present application is specifically described through the following examples, the scope of the present application is not limited by the following examples.

1. Pencil Hardness Measurement Experiment

Specimens coated with the compositions of Examples or Comparative Examples to a thickness of about 0.5 mm were prepared on a 1.5 mm thick ABS (Acrylonitrile Butadiene Styrene) substrate.

Surface pencil hardness of the specimens of Examples or Comparative Examples was measured under a constant load (500 g) using a pencil hardness tester (CB Tech). Pencil hardness was measured by applying scratches at a moving speed of 300 mm/min and a moving distance of 15 mm while maintaining an angle of 45 degrees while changing a standard pencil (Mitsubishi) from 6B to 9H (measurement standard: ASTM D3363). The measurement result is an average value of 10 repeated test results.

2. Surface hardness measurement

A specimen having a thickness of about 1 mm was prepared by maintaining the composition of the following Examples or Comparative Examples at a temperature of 60 ° C. for 12 hours to completely cure it. The surface hardness of the specimen was measured using a Shore D hardness tester (ASKER Co.) at room temperature (about 25° C.) (measurement standard: JIS K 6253).

3. Measurement of mold release time

Based on the time point when the composition of the following Examples or Comparative Examples was heated to a temperature of 70 ° C., the time until the composition became tack free and left no fingerprint mark when pressed with a finger was measured.

4. Light fastness evaluation

The curable composition of the following Examples or Comparative Examples was coated on a glass substrate and cured to prepare a film-formed specimen having a thickness of about 0.5 mm. Subsequently, the specimen was placed on a hot plate set at a temperature of 60 ° C., and at a distance of about 5 cm from the specimen, a spot UV radiator was used to measure the wavelength (280 to 315 nm) in the UV-B region. ) was irradiated with a light amount of 0.8 W/m ² and left for about 65 hours. If yellowing occurred in the film, it was evaluated as Fail, and if yellowing was not observed, it was evaluated as OK.

Example 1 - Two-Part Curable Composition

The first polyol (polyester polyol, Chemtura's Fomrez 1066-560), the second polyol (polyester polyol, Kuraray's P-510) and the catalyst (Aldrich's, dibutyltin dilaurate) were mixed at 80:20:5 (first polyol: A curable composition (main composition part) was prepared by blending in a weight ratio of the second polyol:catalyst).

A curing agent composition part including about 185 parts by weight of an aliphatic polyisocyanate compound (Desmodur XP 2860 from Covestro) was prepared based on 100 parts by weight of the total of the first and second polyols in the subject composition part.

Subsequently, a curable composition was prepared by mixing the curing agent composition part with the subject composition part.

Example 2 and Comparative Example 1 - 2 component curable composition

A two-component curable composition was prepared in the same manner as in Example 1, except that the composition according to Table 1 was formulated.

Example 1 Example 2 Comparative Example 1 Comparative Example 2 subject polyol A 80 70 50 B 30 80 C 20 50 20 catalyst DBTL 5 5 5 5 curing agent isocyanate D 185 145 70 E 145 Unit: parts by weight
OHV: hydroxyl value
A: Fomrez 1066-560 (Chemtura, OHV: 553-567 mgKOH/g, hydroxy equivalent: 100)
B: F-1010 (Kuraray, OHV: 159-176 mgKOH/g, hydroxy equivalent: about 335)
C: P-510 (Kuraray, OHV: 213-235 mgKOH/g, hydroxy equivalent: about 250)
D: Desmodur XP2860 (Covestro Co., NCO%: about 20.0% by weight, isocyanate equivalent: about 215, HDI-based aliphatic polyisocyanate)
E: Desmodur N3600 (Covestro Co., NCO%: 22.5-23.5% by weight, isocyanate equivalent: about 183, HDI trimer aliphatic polyisocyanate)
DBTL: dibutyltin dilaurate (DBTL, Aldrich)

Evaluation results

The physical property evaluation results of the compositions according to Examples and Comparative Examples are shown in Table 2 below.

Example 1 Example 2 Comparative Example 1 Comparative Example 2 pencil hardness H H HB B surface hardness 80 75 60 45 Release time (seconds) 90 90 180 180 light fastness OK OK OK OK

Claims (23)

a first polyol having a hydroxyl value of 400 mKOH/g or more; and a second polyol having a hydroxyl value different from that of the first polyol, including 60% by weight or more of the first polyol,
The first polyol and the second polyol are polycondensation-based polyester polyols each containing a polyhydric polyol unit and a dicarboxylic acid unit,
The polyhydric polyol unit is an aliphatic polyhydric polyol unit,
The dicarboxylic acid unit is an aliphatic dicarboxylic acid unit. The curable composition according to claim 1, wherein each of the first polyol and the second polyol has a hydroxy equivalent weight of 400 or less. delete delete delete delete The curable composition according to claim 1, wherein the first polyol is a polycondensation polyester polyol containing at least one aliphatic polyhydric polyol unit selected from hexanediol units and trimethylolpropane units. The curable composition according to claim 1, wherein the second polyol is a polycondensation polyester polyol comprising at least one aliphatic polyhydric polyol unit selected from a trimethylolpropane unit and a methylpentadiol unit. delete The curable composition according to claim 1, wherein the aliphatic dicarboxylic acid unit is an adipic acid unit. The curable composition according to claim 1, wherein the number average molecular weight of the first polyol or the second polyol is in the range of 500 to 3000 g/mol. The curable composition according to claim 1, comprising the second polyol in an amount of 10 to 60 parts by weight based on 100 parts by weight of the first polyol. a subject composition part that is the curable composition of claim 1; and a curing agent composition part that is present in a state separated from the main composition part and includes a polyisocyanate compound. The two-part curable composition according to claim 13, wherein the polyisocyanate compound is an aliphatic polyisocyanate compound or an aromatic polyisocyanate compound. The two-component curable composition according to claim 13, wherein the molecular weight of the polyisocyanate compound is in the range of 500 to 5000 g/mol. The two-component curable composition according to claim 13, wherein the isocyanate content of the curing agent composition part is 30% by weight or less. The two-component curable composition according to claim 13, wherein the isocyanate equivalent of the curing agent composition part is 250 or less. forming a molded article within a cavity of a mold; and forming a surface coating layer by coating the curable composition of claim 1 on the surface of the molded article. 19. The method of claim 18, wherein the curable composition is injected between the inner wall of the cavity and the surface of the molded article. 19. The method of claim 18, wherein the coating of the curable composition is performed by spraying the curable composition. 19. The method of claim 18, wherein the coating of the curable composition is performed by applying the curable composition. 19. The method of claim 18, wherein the formation of the molded article is performed by injection molding a thermoplastic resin into a cavity of a mold. 19. The method of claim 18, wherein the molded article is an automotive interior material.