KR100432707B1 - Hybrid Polyurethane Resin Composition - Google Patents

Abstract

A one-component polyurethane resin composition excellent in workability and shelf life is disclosed. 20 to 50% by weight of hard segment polyurethane resin, which accelerates initial drying and shorten the recoating time, and 50 to 80% by weight of flexible segment polyurethane resin, which facilitates roller and spray workability and acts as a coating agent. To prepare a one-component polyurethane resin composition comprising a. Excellent workability of top coat and top coat, fast drying time, short repainting time, no difficult working conditions such as two-component paint, and one-component type with excellent hardness and chemical resistance after curing It relates to a polyurethane resin composition.

Description

One-component polyurethane resin composition {Hybrid Polyurethane Resin Composition}

It is related with the one-component polyurethane resin which dries quickly and is excellent in repainting property and excellent in chemical resistance after complete hardening. More specifically, the present invention relates to a one-component polyurethane resin composition having excellent mechanical and chemical properties.

In general, wood coating resins vary widely depending on the application, and lacquer paints containing nitro cellulose to fill the eyes of wood are mainly used as one-component paints. There are fatal defects in physical properties and other one-component paints include UV-curable paints, which require expensive UV curing equipment and paints. And the remaining paint is a variety of polyols and urethane curing agent two-component paints and acid cured two-component paints are used in various ways depending on the use and characteristics of the final product using wood.

However, two-component paints have to be sensitive to the pot life due to the working conditions that require mixing of the main agent and the curing agent in use, and the repainting time is long for two or three times. It needs to be divided into heating and drying conditions, so a lot of work time and expenses are additionally required.

As mentioned above, the new product is a one-component poly with excellent hardness and chemical resistance after hardening. The urethane paint became necessary.

Accordingly, an object of the present invention includes a hard segment polyurethane resin and a soft segment polyurethane resin, which is excellent in workability due to fast drying, and there are no demanding working conditions that require consideration of pot life. Later, to provide a one-component polyurethane resin composition excellent in hardness and chemical resistance.

The present invention to achieve the above object of the present invention

Hard Segment Polyurethane resin 20 to 50% by weight for faster initial drying time and Soft Segment Poly that facilitates roller and spray workability and acts as a coating agent. It provides a one-component polyurethane resin composition containing 50 to 80% by weight of the urethane resin.

By using the one-component polyurethane resin composition according to the present invention to manufacture wood-filled, undercoat, and top coat paints, problems of fatal defects in physical properties such as chemical resistance and hardness of conventional one-component paints can be improved. have.

Hereinafter, the present invention will be described in more detail.

One-component polyurethane resin composition according to the present invention is used to fill the wood blinds and coats, top coat paints to solve the problems of conventional one-component paints. That is, in order to solve the fatal problems in the physical properties such as chemical resistance and hardness in the conventional one-component paint, 20 to 50% by weight of the hard segment polyurethane resin and the soft segment polyurethane resin 50 to 80 A one-component polyurethane resin composition containing weight percent is used. The paint comprising the resin composition of the present invention may be used as a paint for wood blindness and undercoat and top coat when improving the problems of one-component paints and two-component paints.

The hard segment polyurethane resin may be a resin obtained by trimer or triol adduct of toluene diisocyanate, a trimer or biuret reaction of 1.6 hexamethylene diisocyanate, a trimer or triol of isophorone diisocyanate Adductor, trimer of diphenylmethane diisocyanate or adductor resin of triol can be used.

The soft segment polyurethane resin is polyether polyol and polyester polyol and neopentyl glycol, methyl propanediol, 1.6 hexanediol, ethylene glycol, propylene glycol, 1.4 butylene glycol, 1.3 butylene glycol, trimethylol propane And one alcohol selected from the group consisting of trimethylol ethane and castor oil and one isocyanate selected from the group consisting of toluene diisocyanate, 1.6 hexamethylene diisocyanate, isophorone diisocyanate, diphenyl methane diisocyanate, and the like. Can be obtained.

Preferably, the alcohols used in the formation of the hard segment polyurethane resin are polyol and neopentyl glycol, methylpropanediol, 1.6 hexane selected from the group consisting of polyether polyols, polyester polyols and mixtures thereof. It may include at least one selected from the group consisting of diol, ethylene glycol, propylene glycol, 1,4-butylene glycol, 1,3-butylene glycol, trimethylolpropane, trimethylol ethane and castor oil.

In the present invention, in order to obtain the one-component polyurethane resin composition, the mixing ratio of the hard segment polyurethane resin and the soft segment polyurethane resin is such that the hard segment polyurethane resin is It has a range of 20 to 50% and the soft segment polyurethane resin has to be mixed with a range of 80 to 50%.

Preferably, the hard segment polyurethane resin should range from 20% to 50%. If the hard segment polyurethane resin is mixed at 20% or less, the dryness is poor, and the recoating time is long, and the hardness of the varnish may be reduced after complete curing. When the hard segment polyurethane resin is mixed in excess of 50% or more, it is because after complete curing, the coating film is so strong that it hardly crumbles even with a slight impact, making it difficult to form a film as a coating material.

Preferably, the soft segment polyurethane resin should range from 50% to 80%. If the membrane weakness and soft segment polyurethane resin is mixed in excess of 80%, the dryness is poor, the recoating time is long, and the hardness of the varnish may be reduced after complete curing. When the soft segment polyurethane resin is 50% or less, the coating film is too strong after complete curing, and it is difficult to form a film as a coating because it collapses even with a slight impact.

Among the polyols and glycols used in the soft segment polyurethane resin, polyether polyols and polyester polyols are linear types, and the content of polyols having a weight average molecular weight of 500 to 3000 is a total molar ratio of the polyol and glycol. It is preferable to design within the range of 30 to 70 mol% based on the reference. When the weight average molecular weight of the polyol is 500 or less, a soft segment polyurethane resin capable of forming a film cannot be obtained. And when the weight average molecular weight of the said polyol exceeds 3000 or more, the viscosity of resin will become high too much and roller and spray workability will fall, and the polyurethane resin part of a hard segment will become large too much, Chemical resistance may be lowered.

In addition, when the polyol content is 30% or less with respect to the total molar ratio of polyol and glycol, the glycol content of the low molecular weight is 70% or more, so that a soft coating film cannot be obtained and film formation is difficult. In addition, when the content of the polyol is more than 70% with respect to the total molar ratio of the polyol and glycol, the glycol content of the low molecular weight is 30% or less, so that the coating film is too soft to have a soft property, such that the dryness, hardness, chemical resistance, etc. are reduced. do.

In the present invention, it is preferable to design NCO% to 4 to 15% when the hard segment polyurethane resin and the soft segment polyurethane resin are mixed. When the NCO% is 4% or less, the curing density of the urea reaction due to the reaction with moisture may be lowered, thereby decreasing hardness and chemical resistance. If the NCO% is more than 15%, the coating film is too hard to be broken after the coating, so that it is difficult to form a film and the storage property can be stored for a long time.

Hereinafter, the present invention will be described in detail through specific examples.

Preparation of Flexible Segment Polyurethane Resin

Synthesis Example 1

A four-necked flask with a capacity of 2 L was attached with a thermometer, condenser, stirrer, and a temperature raising device. 52 g of neopentyl glycol, 45 g of 1.4 butylene glycol, and 510 g of polyol were mixed and dissolved at 40 ° C. The polyol is an ether polyol having a weight average molecular weight of 1000 and a hydroxyl value of 105 to 110. Subsequently, 392 g of toluene diisocyanate was added thereto, and the mixture was sufficiently reacted at 75 ° C. such that the amount of unreacted toluene diisocyanate was 0.3% or less, followed by butyl acetate to give 50% of solid content, and 6.4% of NCO% of soft segment (Soft Segmen). ) Polyurethane resin was obtained.

Synthesis Example 2

A four-necked flask with a capacity of 2 liters was attached with a thermometer, a condenser and a stirrer temperature raising device. 42g of neopentyl glycol, 45g of 1.4 butylene glycol, 9g of trimethylolpropane, and 510g of polyols were mixed, and it melt | dissolved at 40 degreeC. The polyol is an ether polyol having a weight average molecular weight of 1000 and a hydroxyl value of 105 to 110. Thereafter, 392 g of toluene diisocyanate was added thereto, followed by sufficient reaction to bring the unreacted toluene diisocyanate to 0.3% or less at 75 ° C., followed by butyl acetate to give a solid content of 50%, and a NCO% of 6.3% of a soft segment (Soft Segment). ) Obtained a polyurethane resin

Synthesis Example 3

A four-necked flask with a capacity of 2 liters was attached with a thermometer, a condenser and a stirrer temperature raising device. 67.5 g of methyl propanediol, 45 g of 1.4 butylene glycol, and 450 g of polyol were mixed and dissolved at 40 ° C. The polyol is an ester polyol having a weight average molecular weight of 1800 and a hydroxyl value of 60 to 65. Thereafter, 392 g of toluene diisocyanate was added thereto, and the mixture was sufficiently reacted at 75 ° C. so that the amount of unreacted toluene diisocyanate was 0.3% or less, and then 50% of solid content was used with butyl acetate and 6.6% of NCO% soft segment (Soft Segment). ) Polyurethane resin was obtained.

Integral polyurethane resin composition preparation

Example 1

A four-necked flask with a capacity of 2 L was attached with a thermometer, condenser, stirrer, and a temperature raising device. To this, 700 g of the solid segment polyurethane resin obtained in Synthesis Example 1 and butyl acetate were diluted to 50%, and 300 g of toluene diisocyanate trimer having 16% to 0.2% of NCO% and 0.3g of tinethyl hexanoate were mixed. . As a result, the soft segment polyurethane resin and the hard segment polyurethane resin are hybridized at a ratio of 70/30 to form a one-component polyurethane resin composition having an NCO% of 9.1 to 9.4%. Got

Example 2

A four-necked flask with a capacity of 2 liters was attached with a thermometer, condenser, stirrer and temperature raising device. Here, 600 g of the hard-segmented polyurethane resin obtained in Synthesis Example 2 and butyl acetate were diluted to 50% solids, NCO% was 16 ± 0.2% to 300 g of toluene diisocyanate trimer and 50% solids were diluted with ethyl acetate. 0.3 g of tinethyl hexanoate was mixed with 100 g of a resin to which trimethylol propane was adsorbed to toluene diisocyanate having an NCO% of 17 ± 0.5. As a result, the soft segment polyurethane resin and the hard segment polyurethane resin are hybridized at a ratio of 60/40, so that a one-component polyurethane resin composition having an NCO% of 10.1 to 10.4% is obtained. Got it.

Example 3

A four-necked flask with a 2 L capacity was attached with a thermometer, condenser, stirrer and temperature raising device. To this, 700 g of the hard-segmented polyurethane resin obtained in Synthesis Example 3 and butyl acetate were diluted to 50%, and 300 g of toluene diisocyanate trimer with NCO% of 16 ± 0.2% and 0.3 g of tin ethyl hexanoate were mixed. . Thus, the soft segment polyurethane resin and the hard segment polyurethane resin were hybridized at a ratio of 70/30 to obtain a one-component polyurethane resin composition having an NCO% of 9.2 to 9.6%. .

Example 4

A four-necked flask with a capacity of 2 L was attached with a thermometer, condenser, stirrer, and a temperature raising device. The solid content of the hard-segmented polyurethane resin obtained in Synthesis Example 3 and 600 g of butyl acetate were diluted to 50%, and the solid content was diluted to 50% with 300 g of toluene diisocyanate trimer with 16 ± 0.2% NCO% and ethyl acetate. 100 g of 1.6 hexamethylene diisocyanate trimer having an NCO% of 20.5 to 22% and 0.3 g of tinethyl hexanoate were mixed. As a result, a soft segment polyurethane resin and a hard segment polyurethane resin are hybridized at a ratio of 60/40, and a one-component polyurethane resin composition having an NCO% of 10.8 to 11.2% is obtained. Got it.

Physical properties confirmed by applying the one-component polyurethane resin composition obtained in each of the above examples with varnish are shown in Table 1 as follows.

At this time, the base used as oak wood (oak), which is used for the floor boards of offices or homes, was coated with a roller coating and then dried at room temperature to check the physical properties.

For comparison of the present invention, the nitro cellulose type lacquer is used for the eyes and the undercoat, and the NCO% is used for the alkyd resin polyol having a hydroxyl value of 130 to 150 and an oil% of 30% for the top coat. The toluene diisocyanate having a value of 17 ± 0.5 was cured in a two-part form so that the curing agent adducted with trimethylol propane was 1/1 in each equivalent ratio to be tested in comparison with the varnish of the present invention.

The adducted resin is synthesized by mixing trimethylolpropane in a ratio of 3/1 to monomers of the isocyanates described above, including toluene diisocyanate in general, and synthesized in a state of three isocyanate functional groups, and is used for coating in international and domestic countries. (Adductor resin with NCO% of 13 ± 0.5 is typical when toluene diisocyanate and trimethylolpropane are reacted at a ratio of 3/1 and the nonvolatile content is diluted to 75%.)

Polyurethane resin coating test for wood Properties Example 1 Example 2 Example 3 Example 4 Comparative example Drying minutes Blindfold 3 5 3 8 12 Hado 3 5 3 8 12 normal course 3 5 3 10 90 Glossy (60 °) 100 100 100 100 95 Cross-cut 100/100 100/100 100/100 100/100 100/100 Acid resistance 5% sulfuric acid ◎ ◎ ◎ ◎ ◎ 5% nitric acid ◎ ◎ ◎ ◎ ○ 5% hydrochloric acid ◎ ◎ ◎ ◎ ◎ Alkali resistance ◎ ◎ ◎ ◎ ○ Zhejiang Good Good Good Good Not measurable Pencil hardness 3H 2H 3H 2H H

In Table 1, the evaluation items indicating the characteristics of each paint means the following. ◎ is very good, ○ is good, △ is normal and X is poor in the item of adhesiveness with base or top.

Each characteristic shown in Table 1 was measured by the following method. First, the dryness of the eye filling, the undercoat, and the top coat were confirmed as the time to be repainted, and the other physical properties were checked after the drying at room temperature for 48 hours. And gloss was ASTM-D-523, adhesion was carried out by the NCCA-II-20 method, acid resistance was immersed for 4 hours and confirmed as the degree of swelling and surface state change of the coated site. In addition, alkali resistance was deposited for 4 hours using 20% caustic soda and compared in the same way as acid resistance. Pencil hardness was NCCA-II-12, and storage resistance was completely sealed in a 1 liter canned container at 60 ℃. Checked for 30 days and evaluated for gelation.

As shown in Table 1, by using the one-component polyurethane resin composition according to the present invention has the following advantages when painting the snow and coat, top coat of wood. In other words, the varnish using a one-part polyurethane resin composition in which a hard segment polyurethane resin and a soft segment polyurethane resin are hybridized, has a dryness as an eye, a coat and a top coat of wood. It is fast and has a short recoating time and no demanding working conditions such as two-part coating, and can provide a new one-component polyurethane varnish composition having excellent hardness and chemical resistance after curing.

Although described above with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and changed within the scope of the invention without departing from the spirit and scope of the invention described in the claims below I can understand that you can.

Claims (6)

Hard Segment Polyurethane resin 20 to 50% by weight for fast initial drying and repainting time One-component polyurethane resin composition comprising 50 to 80% by weight of urethane resin. The method of claim 1, wherein the hard segment polyurethane resin is a trimer or triol adduct using toluene diisocyanate, a resin obtained by trimer or biuret reaction of 1.6 hexamethylene diisocyanate, isophorone diisocyanate One-component polyurethane resin composition, characterized in that at least one selected from the group consisting of a trimer or a triol adductor, a dimer methane diisocyanate trimer or a triol adduct resin. The method of claim 1, wherein the soft segment polyurethane resin is a polyether polyol, polyester polyol, neopentyl glycol, methyl propanediol, 1.6 hexanediol, ethylene glycol, propylene glycol, 1,4-butylene glycol , At least one alcohol selected from the group consisting of 1,3-butylene glycol, trimethylolpropane, trimethylolethane and castor oil, toluene diisocyanate, 1.6 hexamethylene diisocyanate, isophorone diisocyanate and diphenyl methane di A one-component polyurethane resin composition obtained by reacting at least one isocyanate selected from the group consisting of isocyanates. According to claim 3, wherein the alcohol is a polyol selected from the group consisting of polyether polyols, polyester polyols and mixtures thereof, neopentyl glycol, methyl propanediol, 1.6 hexanediol, ethylene glycol, propylene glycol, 1,4- A one-component polyurethane resin composition comprising at least one selected from the group consisting of butylene glycol, 1,3-butylene glycol, trimethylolpropane, trimethylolethane and castor oil. The one-component polyurethane resin composition according to claim 4, wherein the polyol is of a linear type and the content of the polyol having a weight average molecular weight of 500 to 3000 is in the range of 30 to 70 mol% based on the total alcohol. . The one-component polyurethane resin composition according to claim 1, wherein the NCO% is 4 to 15%.