KR102356295B1 - Novel compound and composition for drying or curing lacquer sap comprising the same - Google Patents

Abstract

The present invention relates to a novel compound and a composition for drying or curing lacquer containing the same. When a composition of the present invention is used, it can be quickly dried and cured quickly even in a low humidity environment with a relative humidity of 50% or less. An object of the present invention is to provide the composition for drying or curing lacquer containing the novel compound.

Description

Novel compound and composition for drying or curing lacquer sap comprising the same

The present invention relates to a novel compound and a composition for drying or curing lacquer containing the same.

The lacquer tree is known to be native to the highlands of Central Asia, and it is also distributed in China and Korea. The oldest evidence of lacquer is that lacquered coffins have been excavated from tombs from the Silla period. Lacquer wood has been used for various purposes not only in lacquer, the main material of lacquerware, but also in the private sector. In the past, it is said that if you plant a lacquer tree near a well, insects would not gather, and if you put a branch of lacquer tree in the soup, insects will not grow.

In addition, lacquered wooden coffins of Silla tombs were excavated in almost original condition, and a 7th century wooden ship excavated in Japan was also excavated with almost no damage to the hull by lacquer, proving the permanent durability of lacquer. In addition, the lacquer film is not corroded by various strong acids or strong alkalis, and has excellent flame resistance, heat resistance, anti biofouling, waterproof, antiseptic, insect repellent and insulation effects. have it

Korean Patent No. 1991394

An object of the present invention is to provide novel compounds.

An object of the present invention is to provide a composition for drying or curing lacquer containing the novel compound.

An object of the present invention is to provide a method for preparing a novel compound.

An object of the present invention is to provide a method for drying or curing lacquer.

1. A compound represented by the following formula (1) or a stereoisomer thereof:

[Formula 1]

(In Formula 1, n is 5 to 16).

2. The compound according to the above 1, wherein n is 11 or a stereoisomer thereof.

3. A composition for drying or curing lacquer containing the compound of 1 above or a stereoisomer thereof.

4. The composition of 3 above, wherein n is 11.

5. A method for preparing a compound represented by the following formula (1) or a stereoisomer thereof, including a coupling reaction between tyrosine and a compound represented by the following formula (2):

[Formula 1]

(n is 5 to 16 in Formula 1),

[Formula 2]

(In Formula 2, m is 5 to 16,

R ₁ is -OH, -NH ₂ , -Cl, -Br or -I).

6. A method of drying or curing urushi, comprising the step of adding a compound represented by the following formula (1) or a stereoisomer thereof to an urushi solution:

[Formula 1]

(In Formula 1, n is 5 to 16).

7. The method according to 6 above, wherein the compound or a stereoisomer thereof is added by 0.001 to 0.1 mole relative to 1 mole of urushiol contained in the urushi solution.

8. The method according to the above 6, further comprising the step of irradiating the object coated with the urushi solution to which the compound or a stereoisomer thereof is added under a relative humidity of 50% or less;

9. The method according to 8 above, wherein the wavelength of the ultraviolet rays is 254 nm, and the intensity of the ultraviolet rays is 105 W.

When the composition containing the novel compound of the present invention is used, lacquer can be quickly dried and cured quickly even in a low humidity environment of 50% or less relative humidity.

1 is a schematic diagram of the W/O (water in oil) emulsion structure of the lacquer solution and the polymerization mechanism according to drying ( FIG. 1a ) and the polymerization mechanism of urushiol according to ultraviolet irradiation ( FIG. 1b ).
2 shows a cured bed under controlled temperature (25° C.) and humidity (relative humidity of 50% or less) conditions used in Examples.
3 is a result of measuring the drying time of raw lacquer according to ultraviolet irradiation.
Figure 4 shows the drying time of the lacquer sap solution (LSS, Lacquer sap solution) according to the ultraviolet irradiation and the infrared spectrum before and after ultraviolet irradiation.
5 shows a schematic diagram of the development of a lacquer material with improved drying time and curing characteristics by applying additives and UV irradiation.
6a and 6b show the synthesis process of Y-ADDA (tyrosine-aminododecanoic acid).
7 shows the results of matrix assisted laser desorption ionization-time of flight mass spectrometer (MALDI-ToF) mass spectrometry and high-performance liquid chromatography (HPLC) analysis of the synthesized Y-ADDA.
8 is a photograph showing the dispersibility of LSS according to the addition of Y-ADDA as a photocuring agent and drying experiments in the curing bed after application of the solution to glass.
9 is a result of observing an emulsion solution of LSS with LSS and three types of photocuring agents (Fmoc-Try(tBu)-OH, Shellac and Y-ADDA) added thereto under an optical microscope.
10 shows the drying time and surface morphology of LSS to which Fmoc-Try(tBu)-OH is added as a photocuring agent.
11A and 11B show spectral changes through Fourier transform infrared spectroscopy (FTIR) of LSS to which Fmoc-Try(tBu)-OH is added as a photocuring agent.
12 shows the drying time and surface morphology of LSS to which Shellac is added as a photocuring agent.
13a and 13b show spectral changes through FTIR of LSS to which Shellac was added as a photocuring agent.
Figure 14 shows the spectrum change through drying time and FTIR of LSS to which Y-ADDA was added as a photocuring agent.
15 shows the change in transmittance of UV-treated lacquer samples when each photocuring agent (Fmoc-Try(tBu)-OH, Shellac and Y-ADDA) was added.
16 is a cross-cut adhesion test showing the adhesion of UV-treated lacquer samples when each photocuring agent (Fmoc-Try(tBu)-OH, Shellac and Y-ADDA) was added.
17 shows the results of measuring pencil hardness, transmittance, and haze of the lacquer solution to which each photocuring agent (Fmoc-Try(tBu)-OH, Shellac and Y-ADDA) was added.
18 is a graph showing the measurement of drying time according to whether or not the ultrasonic treatment of the lacquer solution to which each photocuring agent (Fmoc-Try(tBu)-OH, Shellac and Y-ADDA) is added.

Hereinafter, the present invention will be described.

The present invention provides a compound represented by the following formula (1) or a stereoisomer thereof.

[Formula 1]

(In Formula 1, n is 5 to 16).

The compound of the present invention is a form in which a carbon chain of a tail structure is bonded to tyrosine (Y). For example, the carbon chain may be an unsaturated aliphatic hydrocarbon or a saturated aliphatic hydrocarbon.

In one embodiment of the present invention, n in Formula 1 may be 11. In this case, the compound of the present invention may be in the form of tyrosine combined with aminododecanoic acid (ADDA).

A stereoisomer refers to a compound having the same bonding structure but different spatial arrangement of atoms or groups, and includes, for example, diastereomers and enantiomers.

The present invention provides a composition for drying or curing lacquer containing a compound represented by the following formula (1) or a stereoisomer thereof.

[Formula 1]

(In Formula 1, n is 5 to 16).

The isomer may be within the range described above, but is not limited thereto.

Lacquer can be used interchangeably with raw lacquer, lacquer extract, lacquer sap, and lacquer. Lacquer refers to the milky white water-in-oil emulsion liquid that is secreted when the epidermis of poison ivy is injured. Lacquer is a natural coating material that has many advantages such as high durability, high strength, heat resistance, high gloss, antibacterial properties, insect repellency, and insulation. Lacquer is composed of 60~70% of catechol (ex. urushiol, laccol, thistsiol), glycoprotein, polysaccharide, and 1-2% of laccase enzyme. has been Laccase enzyme and polysaccharides exist in the microdroplets inside the lacquer, and copper ions present in the laccase enzyme react with oxygen in the air to cause polymerization of catechol molecules.

Drying or curing of lacquer takes a long period of time (1 to 7 days) at relatively high humidity (75% to 95% relative humidity) in general, so it takes a long time and is difficult to work. Although the mechanism of drying or curing of the lacquer film has not been clearly elucidated, exposing the lacquer film to a high-humidity environment allows water to penetrate the film and enhance the reactivity of the laccase enzyme, which is active in water, and reduces the polymerization reaction of catechol molecules. is understood to be induced. At this time, it is considered that the emulsion structure of lacquer is broken and water escapes from the polymerized coating film.

Urushiol is a representative catechol-family molecule included in urushi, and is a form in which a carbon chain having a tail structure is bonded to a catechol. For example, urushiol includes a compound represented by the following formula (3).

[Formula 3]

In Formula 3, R is

,

,

,

,

,

,

,

,

또는

or

일 수 있으나, 이에 제한되는 것은 아니다.

may be, but is not limited thereto.

Urushiol monomers are known to polymerize by means of copper ions, ultraviolet rays or catalysts in laccase enzymes. It is possible to form a network-structured curable polymer through the polymerization reaction, so that the lacquer-coated object can be coated.

The present inventors prepared a novel compound having a structure similar to that of urushiol contained in urushiol by focusing on the polymerization reaction between urushiol monomers.

The compound included in the composition of the present invention may be polymerized with the urushiol monomer contained in urushi, and the composition of the present invention may be used for drying or curing urushi. In this case, there is an advantage that quick drying and curing are possible even in a low humidity environment (eg, relative humidity of 50% or less). Specifically, the composition of the present invention can be used for UV (Ultraviolet rays) curing of lacquer. In this case, unlike polymerization by a laccase enzyme, oxygen is unnecessary, and polymerization is performed by directly forming a radical in the tail structure portion of the compound represented by Formula 1, so that the curing speed is further accelerated. Since the composition of the present invention contains natural peptides, it can be used environmentally.

Drying refers to the act of removing one or more volatile liquids from a subject, which may be by heat, light or other energy.

Hardening is a phenomenon in which the liquid contained in an object loses fluidity due to chemical changes such as hydration, oxidation, neutralization, or physical changes such as drying, and increases rigidity and strength. including solidification.

The present invention provides a method for preparing a compound represented by the following Chemical Formula 1 or a stereoisomer thereof.

[Formula 1]

(In Formula 1, n is 5 to 16).

The isomer may be within the range described above, but is not limited thereto.

The preparation method of the present invention includes a step of coupling reaction between tyrosine and a compound represented by the following Chemical Formula 2;

[Formula 2]

(In Formula 2, m is 5 to 16,

R ₁ is -OH, -NH ₂ , -Cl, -Br, -I).

Coupling reaction refers to various reactions in which specific functional groups of two compounds are combined.

In one embodiment of the present invention, in Formula 1, n is 11, and in Formula 2, m is 11, R ₁ may be -OH, and in this case, the compound represented by Formula 2 is ADDA (12-aminododecanoic acid) ) can be In this case, the coupling reaction of tyrosine and the compound (ADDA) represented by Formula 2 may include providing a resin from which a fluorenylmethoxycarbonyl (Fmoc) protecting group has been removed; coupling Fmoc-tyrosine to the resin; removing the Fmoc protecting group from the coupled tyrosine; coupling Fmoc-ADDA to the coupled tyrosine; and removing the Fmoc protecting group from the coupled ADDA.

The Fmoc protecting group serves to block side reactions by protecting the amino group so that the amino group does not participate in the reaction. In addition to the Fmoc protecting group, any protecting group capable of performing the same function may be used without limitation. The Fmoc protecting group may be a compound represented by Formula 4 below.

[Formula 4]

The Fmoc-tyrosine refers to a compound in which a partial functional group of tyrosine or a derivative thereof is bonded to an Fmoc protecting group. Fmoc-tyrosine may be a compound represented by the following Chemical Formula 5 or 6.

[Formula 5]

[Formula 6]

The Fmoc-ADDA refers to a compound in which a partial functional group of ADDA or a derivative thereof is bonded to an Fmoc protecting group. Fmoc-ADDA may be a compound represented by the following formula (7).

[Formula 7]

The resin is not limited as long as it is used for solid-phase peptide synthesis, and may be, for example, MBHA (4-methylbenzhydrylamine) resin.

The present invention provides a method for drying or curing lacquer.

The drying or curing method of the present invention includes a step of adding a compound represented by the following Chemical Formula 1 or a stereoisomer thereof to an urushi solution.

[Formula 1]

(In Formula 1, n is 5 to 16).

Isomers, lacquer, drying and curing may be within the above-described ranges, but are not limited thereto.

Lacquer solution is a solution containing lacquer and can be applied to the object to be lacquered. The lacquer solution may further include, for example, turpentine oil (turpentine oil, turpentine oil, turpentine oil) in addition to lacquer. The volume ratio of lacquer and turpentine in the urushi solution is, for example, 1:10 to 10:1, 1:9 to 9:1, 1:8 to 8:1, 1:7 to 7:1, 1: 6 to 6:1, 1:5 to 5:1, 1:4 to 4:1, 1:3 to 3:1, or 1:2 to 2:1, but is not limited thereto.

The compound or a stereoisomer thereof may be added in 0.001 to 0.1 mol, 0.001 to 0.05 mol, 0.001 to 0.01 mol, or 0.001 to 0.005 mol relative to 1 mol of urushiol contained in the urushiol solution, but is not limited thereto. The method of the present invention has an excellent drying or hardening effect of lacquer even when an urushi solution to which a low concentration of a compound is added is used.

The drying or curing method of the present invention may further include the step of irradiating the object to which the lacquer solution to which the compound represented by Formula 1 or a stereoisomer thereof is added is applied under a relative humidity of 50% or less; The wavelength of the irradiated ultraviolet rays may be, for example, 180 nm to 300 nm. The intensity of the irradiated ultraviolet light may be 45 W to 105 W, but is not limited thereto.

When the drying or curing method of the present invention is used, there is an advantage that rapid drying and curing are possible even in a low humidity environment (relative humidity of 50% or less), and since natural peptides are used, it can be dried or cured in an environmentally friendly manner.

Hereinafter, examples will be given to describe the present invention in detail.

Example

I. UV light curing mechanism investigation and irradiation environment optimization

1. Mechanism investigation for UV photocuring additive design

The solution has a W/O (Water in Oil) emulsion structure as shown in FIG. 1A, and is polymerized by a laccase enzyme, and radicals generated by oxygen are added to glycoprotein, which is not soluble in water. Through the process of being converted to urushiol in the oil phase by the Urushiol-based urushiol solution polymerization process can promote radical generation upon UV irradiation, thereby accelerating aerobic oxidation and inducing faster polymerization (Fig. 1b). Therefore, by designing and introducing an additive capable of accelerating curing during UV irradiation, a photocuring fast-curing type lacquer material can be developed. However, the additive must be well emulsified in the lacquer emulsion and be able to maintain the unique eco-friendly characteristics of lacquer lacquer.

2. Development of UV-applicable curing bed in low humidity environment (~50%RH)

General lacquer lacquer has a problem that it takes more than 6 hours to dry (dry to the touch) and more than 10 hours to cure in a high humidity environment of 20℃-25℃, 70%RH-90%RH. In particular, lacquer has a problem in that it does not dry and harden in a low humidity environment of 50%RH or less. However, since this example aims to develop an lacquer solution that can be used as lacquer by fast curing in a low-humidity environment, a large-area curing bed system that can be irradiated with UV under the same temperature and humidity controlled for each experimental group was developed (Fig. 2). ). The curing bed system developed by the present inventors can control the irradiation intensity by connecting 7 lamps with 15W at a wavelength of 254 nm and maintain a low-humidity environment.

3. Check the drying time of fresh paint and Lacquer sap solution (LSS) according to the UV irradiation intensity in a low humidity environment (50%RH or less)

3 is a result of measuring the drying time of lacquer by applying 100 μL of raw lacquer and varying the irradiation intensity of UV (254 nm) to 0, 45, and 105 W under an environment of 25° C. and 50% RH or less (TFD=touch- free dry, dry to touch time). When UV irradiation was not performed (0 W), it was not dried in an environment of 50% RH or less (FIG. 3). However, when 45 W UV was irradiated for 4 hours, it was confirmed that dry to touch properties appeared, and when stronger UV irradiation (105 W), the drying time was shortened to 3 hours. It was confirmed that it can be promoted. However, when the film was observed with an optical microscope during strong UV irradiation, it was confirmed that more wrinkles were generated on the surface ( FIG. 3 , surface morphology). That is, it can be seen that the curing speed of raw lacquer was accelerated by UV, but as above, the spreadability was poor, and wrinkles were generated on the surface of the final film coating film, so that the transmittance was significantly lowered.

Therefore, Lacquer sap solution (LSS) was prepared by mixing turpentine oil and fresh paint at a 1:1 volume ratio, and whether it was cured under high-power UV (254 nm, 105 W) irradiation conditions, which dries the fastest in fresh paint It was confirmed (Fig. 4, 25 ℃, 50%RH or less). It was confirmed that the spreadability was remarkably good, and when high-power UV was used for lacquer, drying to the touch was achieved within 1 hour even in a low-humidity environment of 50%RH or less (FIG. 4). FT-IR was measured at 1-hour intervals to confirm the degree of hardening of the lacquer. As a result, the =CH peak (3010 cm ^-1 ), which is an indicator of the degree of curing of Urushiol, was relatively faster than the same peak of the lacquer without UV irradiation. It was confirmed that the decrease (FIG. 4).

II. Investigation of emulsion state when searching and adding UV photocuring additives

1. Lipid mimic Y-ADDA, Fmoc-Tyr(tBu)-OH, Shellac additive selection

As shown in Figure 1, the lacquer solution is in the form of a W/O emulsion, and maintains the lipid form to maintain the emulsion form due to the proposed mechanism. The amino acid tyrosine (Tyr, tyrosine) was introduced. This was named Y-ADDA. In addition, tyrosine and Shellac, which are readily available as natural additives, were selected to expand their applicability (FIG. 5). In particular, Shellac is one of the natural and animal resins used to make varnish. It has excellent adhesion and prevents moisture penetration. As it is an eco-friendly material, it can be sufficiently removed with ethanol, and has little yellowing and no coloration. The composition is very fast and the strength is not high, but the hardness is high, so it is difficult to use as a top coat. On the other hand, since lacquer is relatively slow to dry and can be cured quickly, it can be expected that lacquer materials with fast drying and curing times and good coating properties can be developed by manufacturing a mixture of two natural lacquers.

2. Synthesis of Lipid-mimicking Y-ADDA Additive

For the same purpose as in 1 above, tyrosine, an amino acid capable of radical dimerization by UV irradiation, was introduced into ADDA (12-aminododecanoic acid) having a tail structure through a solid phase synthesis method. The synthesis process was designed to first synthesize the Fmoc-ADDA-OH precursor (FIG. 6a), and then remove the Fmoc protecting group after introducing tyrosine to Fmoc-ADDA-OH to finally obtain Y-ADDA (FIG. 6b). Whether or not the final Y-ADDA was synthesized was confirmed to be consistent with the theoretical value through MALDI-ToF (Matrix Assisted Laser Desorption Ionization-time of flight mass spectrometer) mass spectrometry. -performance liquid chromatography) was confirmed (FIG. 7).

3. Investigation of solution state when adding photocuring additives

In order to confirm the dispersibility of the synthesized and natural additives, a Y-ADDA high-concentration solution was first prepared and added to the LSS solution. The mixed lacquer solution exhibited very good spreadability without aggregation, and was applied on glass to evaluate drying time and coating film properties, and was irradiated with UV 254 nm under conditions of 25° C. and 50% RH or less (FIG. 8). In order to more closely grasp the dispersibility of the emulsion state when the photocuring agent is added, W/O emulsion droplets were observed with an optical microscope (FIG. 9). In the case of LSS, it was confirmed that W/O was evenly distributed when observed with an optical microscope. When 0.1 eq. of Fmoc-Tyr(tBu)-OH, Shellac, and Y-ADDA were added, uniform dispersibility was confirmed with the naked eye, but when microscopically observed with an optical microscope, Y-ADDA photocuring additive designed similar to urushiol It was confirmed that it showed the most even dispersibility (FIG. 9).

Ⅲ. Reduction of drying and curing time by each photocuring additive and evaluation of coating film properties

1. Changes in drying and curing properties of lacquer according to the concentration of Fmoc-Tyr(tBu)-OH

When Fmoc-Tyr(tBu)-OH is added at different concentrations of 0.001, 0.01, 0.05, 0.1 eq. to LSS solution in a low humidity environment of 50%RH or less, the higher the concentration of Fmoc-Tyr(tBu)-OH It was confirmed that the drying time was shortened (FIG. 10). Looking at the surface morphology of lacquer with different concentrations of Fmoc-Tyr(tBu)-OH, if you look at the image photos, the lower the concentration of Fmoc-Tyr(tBu)-OH, the more uniform the surface is. It can be confirmed that a large aggregation phenomenon occurs on the surface (FIG. 10). As the concentration of Fmoc-Tyr(tBu)-OH added to the lacquer solution increased, upon UV irradiation, the viscosity increased and the moisture decreased, and drying was performed quickly, but it is thought that an excess of tyrosine additive was precipitated accordingly (Fig. ). 0.05 eq. After the addition, the drying time was not shortened any more, and it was inferred that macro-agglomeration was observed on the surface when more was added ( FIG. 10 ).

Looking at the FTIR data of the sample to which Fmoc-Tyr(tBu)-OH was applied (FIGS. 11a and 11b), =CH peak (3010 cm ^-1 ) related to the curing of urushiol was generally reduced within 3-4 hours. It can be seen that the higher the concentration, the greater the degree of reduction of the peak. As described above, it was confirmed that the drying and curing rates were shortened by UV irradiation when Fmoc-Tyr(tBu)-OH was added to LSS.

2. Changes in drying and curing properties of lacquer according to Shellac concentration

Shellac is mainly used in liquid form, but in this study, 0.001, 0.01, 0.05, 0.1 eq. was applied to the LSS solution at a concentration of (Fig. 12). The drying time of the lacquer solution to which Shellac was applied was shortened as the concentration of Shellac was higher, and the drying time of the sample to which 0.001 eq. was applied was 60 minutes, which is not different from the drying time of the lacquer solution without Shellac added. The drying time of the applied sample was greatly reduced to 35 minutes (FIG. 12). It can be seen that the lower the concentration of Shellac, the more uniform the surface is formed, and the higher the concentration, the more wrinkles are formed on the surface. is formed by occurrence (FIG. 12). In particular, when comparing the change in the drying time to the touch of the lacquer sample to which Shellac was applied with the change in the drying time to the touch of the lacquer sample to which Fmoc-Tyr(tBu)-OH was applied (1), 0.001, 0.01, and 0.05 eq. up to , shows a similar trend ( FIGS. 10 and 12 ). On the other hand, 0.1 eq. In the case of , the lacquer sample to which Fmoc-Tyr(tBu)-OH was applied had no difference in drying time to the touch compared to that applied to 0.05 eq. and Fig. 12).

Looking at the change in =CH peak (3010 cm ^-1 ), which is an indicator of the degree of hardening of urushiol, in the FTIR measurement result of the lacquer sample to which Shellac is applied, it can be seen that the curing is completely completed within 2-3 hours, and the concentration of Shellac According to the change, it was confirmed that there was also a change in =CH peak (3010 cm ^-1 ) of the same time period ( FIGS. 13a and 13b ). Considering this, compared to Fmoc-Tyr(tBu)-OH, Shellac is effective in shortening the curing time as well as the drying time of lacquer, and it is judged to be a photocuring additive that enables an even coating film surface.

3. Changes in drying and curing properties of lacquer according to Y-ADDA application

When the synthesized Y-ADDA was added to the LSS solution at different concentrations of 0.001, 0.01, 0.05, and 0.1 eq., it can be confirmed that all of them reach dryness to the touch within 30 minutes even if a very small amount is added (FIG. 14). Looking at the FTIR measurement results of the samples to which Y-ADDA was applied, it can be seen that the =CH peak, which is an indicator of the degree of hardening of urushiol, was greatly reduced in 2 hours and there was no change thereafter. (FIG. 14, Integral area of peak).

4. Conclusion

Among the three eco-friendly photocuring additives used in this example, it was confirmed that the drying time and curing time were the most shortened when irradiating UV 254 nm under the conditions of 25℃ and 50%RH or less of the LSS lacquer sample to which the lipid mimic Y-ADDA was applied. became Through this, it is very important to design a photocuring additive by imitating the structural and functional characteristics of urushiol in order to understand the emulsion structure of lacquer and its polymerization mechanism so that the curing process can be effectively performed.

IV. Measurement of transmittance of lacquer by UV and evaluation of adhesion

1. Analysis of the permeability of lacquer according to the concentration of additives

As shown in FIG. 15 , as the concentration of the additive increases, the transmittance tends to decrease. As the concentration of the additive increases, it is considered that more wrinkles are formed on the surface, resulting in a lot of light scattering and a significant decrease in transmittance. 0.1 eq. It is considered that the transmittance of the lacquer is further reduced when the lacquer solution to which the concentration of additives is applied is treated with ultrasonic waves. When the lacquer solution is treated with ultrasonic waves, the viscosity of the lacquer solution is greatly increased, which is thought to cause the surface of the lacquer to dry faster by UV light, resulting in large wrinkles on the surface.

2. Evaluation of adhesion of lacquer according to the concentration of additives

As shown in Fig. 16, the adhesive strength was evaluated by applying lacquer containing each additive to the pine board, UV irradiation in a low-humidity environment, manufacturing a coating film, and examining the desorption rate of the thin film through a Cross-Cut Adhesion Test. As a result, it was confirmed that the adhesive strength was improved as the concentration of the additive increased (FIG. 16). In the case of the Y-ADDA-added LSS solution, which had a relatively high film uniformity, it was confirmed that the adhesive strength was the best (Fig. 16d), and in the case of the Fmoc-Tyr(tBu)-OH additive, which was deposited on the surface at a certain concentration or higher, the coating film after drying was confirmed to have the highest desorption rate (FIG. 16b).

3. Measurement of haze and hardness according to additive concentration

As shown in FIG. 17, it was confirmed in the LSS film containing three types of photocuring agents that the haze increased as opposed to the transmittance as the amount of the added curing agent was increased, and as expected, Fmoc-Tyr ( tBu)-OH showed the highest haze. Hardness was measured using a pencil hardness tester. Fmoc-Tyr(tBu)-OH had the lowest hardness, and the thin film composed of LSS solution containing Shellac and Y-ADDA showed similar hardness. It was confirmed that the hardness increased from 2B to H (FIG. 17).

Ⅴ. Evaluation of drying and curing properties after manufacturing nano-emulsion by ultrasonic treatment of LSS solution with photocuring agent added

1. Changes in drying and curing properties of lacquer due to ultrasonic treatment

It was confirmed that the drying time was greatly shortened when the lacquer was dried after preparing the nano-emulsion through ultrasonication of the LSS solution. photocuring agent 0.1 eq. After addition, after ultrasonic treatment (100 W, 42 kHz) for 30 minutes, it was applied to the substrate and irradiated with UV (254 nm) under conditions of 25° C. and 50% RH or less to check the drying time to the touch. In the case of Y-ADDA, the drying time was significantly shortened only by adding a photocuring agent, and the film drying time after the nanoemulsion was prepared at a similar level (FIG. 18). In the case of Fmoc-Tyr(tBu)-OH and Shellac, it was confirmed that the drying time reduction rate was improved from 25% to 33% and from 41% to 50%, respectively (FIG. 18).

Claims (9)

A compound represented by the following formula (1) or a stereoisomer thereof:
[Formula 1]

(n is 5 to 16 in Formula 1).
The compound according to claim 1, wherein n is 11 or a stereoisomer thereof.
A composition for drying or curing lacquer, comprising the compound of claim 1 or a stereoisomer thereof.
The composition of claim 3, wherein n is 11.
delete A method for drying or curing urushi, comprising the step of adding a compound represented by the following formula (1) or a stereoisomer thereof to an urushi solution:
[Formula 1]

(n is 5 to 16 in Formula 1).
The method according to claim 6, wherein the compound or a stereoisomer thereof is added by 0.001 mol to 0.1 mol relative to 1 mol of urushiol contained in the urushi solution.
The method according to claim 6, further comprising: irradiating an object to which the lacquer solution to which the compound or a stereoisomer thereof is added is applied under a relative humidity condition of 50% or less.
The method of claim 8 , wherein the wavelength of the ultraviolet light is 254 nm and the intensity of the ultraviolet light is 105 W.

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