KR20030031876A - Method for preparing methyl methacrylate resin containing photochromic compound and MMA resin forms using the same - Google Patents

Abstract

PURPOSE: A method for preparing a methyl methacrylate resin containing a photochromic compound and a resin molded product using the resin are provided, to enable the photochromic compound to be infiltrated into the resin uniformly and to improve the concentration of color and the color change velocity. CONSTITUTION: The method comprises the steps of adding 0.01-0.02 parts by weight of an organic acid and 0.1-1 parts by weight of a photochromic compound to a solvent mixture consisting of 100 parts by weight of methyl methacrylate with a boiling point of 60-100 deg.C, 0.1-5 parts by weight of n-hexane, 5-15 parts by weight of an UV screening agent, 0.1-5 parts by weight of trichloroethane and 0.1-5 parts by weight of methylisobutyl ketone, and polymerizing the mixture at a temperature of 70-90 deg.C for 20-40 min; adding 0.1-5 parts by weight of a curing agent to the obtained one and curing it in water of about 50 deg.C for 3-4 hours; treating the cured one with the steam of about 100 deg.C for 30-35 hours; and coating the treated one with a coating agent at about 75 deg.C for 10-15 sec. Preferably the photochromic compound is naphtopyrane-based compound; and the organic acid is at least one selected from the group consisting of HNO3, HCl and H2SO4.

Description

Method for preparing methyl methacrylate resin containing photochromic compound and resin molding using the same {Method for preparing methyl methacrylate resin containing photochromic compound and MMA resin forms using the same}

The present invention relates to a method for preparing a methyl methacrylate (hereinafter referred to as "MMA") resin containing a photochromic compound and a resin molding using the same, and more specifically, the photochromic compound is uniformly formed with MMA. The present invention relates to a method for preparing an MMA resin containing a photochromic compound capable of changing color in various products, and a resin molding using the same.

In general, photochromicity refers to a reversible photochromic phenomenon caused by a compound that changes color under ultraviolet light, such as sunlight or artificial illumination including ultraviolet light, and returns to a colorless transparent color under ultraviolet light protection or in the dark.

These photochromic materials exist in a double bottom state that absorbs ultraviolet rays strongly and absorbs visible light strongly. Thus, the photochromic material is colored when exposed to UV rays and then converted into a colorless transparent state when blocked by UV rays. As a compound that provides a variety of colors depending on the presence or absence of ultraviolet rays, the type is benzopyran-based compound (Korean Patent Application No. 98-018556), naphthopyran-based compound (Korean Patent Publication No. 99-0170432) , Spiroxazine-based compounds and spiropyran-based compounds (Korean Patent Application No. 90-701930).

Until now, such photochromic compounds have been mainly used in glass such as automobiles and buildings, or have been used in the manufacture of ophthalmic glass such as sunglasses or glass or plastic lenses. For example, Korean Patent Publication No. 94-07779 provides a product having an organic photochromic material in a plastic matrix such as a photochromic ophthalmic lens and a car roof skylight.

Recently, cosmetic products and coating agents (Korean Patent Application Nos. 99-06814 and 99-048421), such as cosmetics or nail polish (Korean Patent Application No. 99-06813), which focus on photochromic properties of photochromic compounds, The use of compounds is expanding.

Meanwhile, until now, such photochromic compounds are used to provide various colors. In the manufacture of products, the photochromic compounds are incorporated into raw materials, or these compounds are dissolved in a solvent together with a polymer and then coated. It has been used by a method of forming a film.

For example, in Korean Patent Application No. 2001-1402, 20-30% by weight of resin, 1-3% by weight of camphor, 4-6% by weight of dibutyl phthalate, 4-6% by weight of ethyl acetate, 12-18% by weight of toluene , 12-18 wt% butyl acetate, 4-6 wt% isopropyl alcohol, 10-12 wt% cellulose acetate butyrate, 0.1-0.3 wt% polyethylene wax, 8-12 wt% methyl isobutyl ketone, methyl isoethyl ketone 10 A photochromic trinket accessory coating / printer composition comprising from 15% by weight to 0.5% by weight and a photochromic compound is disclosed. Korean Patent Laid-Open No. 2001-84405 discloses a mixture of toluene / alcohol with a spiropyrane type photochromic compound. The solution dissolved in the solvent was physically chemically bonded to the resin granules at 20 to 50 ° C. for 0.05 to 48 hours, and then heated to 160 to 300 ° C. to form a photochromic resin molded product. It discloses a method.

In addition, Korean Patent Application No. 2001-29435 discloses 30 to 50 parts by weight of methyl ethyl ketone, 10 to 20 parts by weight of toluene, 10 to 20 parts by weight of xylene, 5 to 10 parts by weight of ethyl acetate, and 5 to 10 parts by weight of isopropyl alcohol. After mixing the fragrance 0.001-5 parts by weight and the photochromic compound 0.1-20 parts by weight, 50-100 parts by weight of the resin was added and immersed for 1 to 24 hours, and after stirring uniformly, the solvent was dried and primary grinding Then, a method for producing a master batch of a photochromic resin molding which is rapidly cooled after heating is disclosed.

However, the coating layer of the molded article provided by such a method is easily peeled off or the particles of the photochromic compound are detached, and thus, despite the excellent discoloration characteristics of the photochromic compound, these compounds have a better and smoother uniform coating layer formation. There have been many limitations on the use, such as not being able to use variously in a wide range of other required fields.

In addition, the coating product provided by the above method was not only poor in durability, but also had a disadvantage in that the photochromic compound was not uniformly physicochemically bonded to the resin. In addition, there is no example in which the photochromic compound is bound to MMA.

Accordingly, in the present invention, as a result of extensive research in order to solve the above-mentioned problems, lower alcohols and lower acetates in the combined organic solvent used as the solvent of the photochromic compound destroy the molecular structure of the photochromic compound, thereby causing problems in durability. In the organic solvent except for this, it was found a method that can penetrate the photochromic compound to the MMA resin in a certain concentration in a certain concentration, the present invention was completed based on this.

Accordingly, an object of the present invention is to provide a method for producing an MMA resin containing a photochromic compound which is excellent in durability of a photochromic resin molding and can shorten the time of color change.

Another object of the present invention is to provide a molded article using the photochromic MMA resin obtained from the above method.

MMA resin containing a photochromic compound of the present invention for achieving the above object is 100 parts by weight of MMA having a boiling point of 60 to 100 ℃, 0.1 to 5 parts by weight of normal hexane, 5 to 15 parts by weight of UV blocker, Triclo After mixing 0.01-0.2 weight part of organic acids and 0.1-1 weight part of photochromic compounds in the mixed organic solvent which consists of 0.1-5 weight part of rotane and 0.1-5 weight part of methyl isobutyl ketones, it is 20-40 minutes at 70-90 degreeC. And the curing agent for about 3 to 4 hours in water at about 50 ° C., followed by 30 to 35 minutes of steam at about 100 ° C., followed by coating at about 75 ° C. It consists of coating for 10-15 seconds.

The photochromic MMA resin molding for achieving another object of the present invention is obtained from the above method, and various panes, windshields, optical lenses, glasses, skylights, curtain boards, doors, signs, fluorescent lamps, ornaments, ornaments, medical It can be used as an instrument, daily miscellaneous goods, meter instrument or aircraft parts.

Looking at the present invention in more detail as follows.

As described above, the manufacturing method of the MMA resin of the present invention is mixed with a mixed organic solvent consisting of trichloroethane, normal hexane and methyl isobutyl ketone and a photochromic compound to the MMA resin having a specific boiling point, and then polymerized and coated Let's do it.

According to the present invention, lower alcohols such as ethyl alcohol or isopropyl alcohol and lower acetates such as ethyl acetate or butyl acetate are used in the mixed organic solvent used as the solvent of the photochromic compound. The structure was destroyed to reduce the color durability of the photochromic resin molding, and the present invention eliminated their use in the mixed organic solvent.

In the present invention, a preferred mixed organic solvent for dissolving 0.1 to 1 parts by weight of the photochromic compound is 0.1 to 5 parts by weight of normal hexane, 0.1 to 5 parts by weight of trichloroethane and 0.1 isobutyl ketone relative to 100 parts by weight of MMA. It consists of-5 weight part.

The composition of the mixed solvent was selected from various resins in consideration of the vividness of color during UV discoloration, stability of boiling point at high temperature penetration of resin, improvement of penetration rate in terms of reaction kinetics and solubility of photochromic powder.

In particular, in the present invention, 0.1 to 5 parts by weight of trichloroethane is used as a mixed organic solvent, and the trichloroethane has not been used as a solvent for a photochromic compound. If the amount of trichloroethane is less than 0.5 parts by weight, the color supersaturation phenomenon may cause the photochromic compound to desorb or dissolve in the MMA, resulting in unstable coating and coloration. Can be.

On the other hand, the total amount of the organic solvent is preferably 0.5 to 10 parts by weight based on 100 parts by weight of MMA. If the amount of use exceeds 10 parts by weight, the plate may be bent in the process of manufacturing the plate or bubbles may not be smooth. If the amount of the solvent is less than 0.5 part by weight, the solubility of the photochromic compound is decreased and the MMA becomes opaque. It does not melt completely, so that the photochromic compound is not evenly distributed on the plate. In addition, the photochromic compound particles are aggregated, resulting in an uneven plate.

The photochromic compound suitable for the present invention is preferably a naphthopyran-based compound, and when the benzopyran-based compound (Korean Patent Application No. 98-018556) is used, the photochromic particles are desorbed during the physicochemical reaction of the MMA resin. The concentration is low and there is a problem of durability.

Current naphthopyran-based compounds include BLUE SKY, VIOLET, ORANGE, and YELLOW. They show a difference in color density according to the intensity of the ultraviolet light, and color difference and density difference depending on the solvent and the combination of each color.

On the other hand, as for the boiling point of MMA resin used for this invention, 60-100 degreeC is preferable. If the boiling point is lower than 60 ℃, there is a risk of explosion and there is a risk of fire caused by the gas (Gas) emitted, and if the boiling point is higher than 100 ℃, difficulties in the polymerization process. Commercially available products include LG's MMA.

In addition, 0.1 to 2 parts by weight of organic acid (nitric acid, hydrochloric acid and / or sulfuric acid) may be added to the mixture to improve color clarity upon UV discoloration. At this time, when the amount of the organic acid used is less than 0.01 part by weight, there is almost no effect of addition, and when the amount of the organic acid exceeds 0.2 part by weight, the molecular structure of the photochromic compound is destroyed, thereby decreasing the color durability of the photochromic compound and the molded product.

According to the present invention, 0.01 to 0.2 parts by weight of an organic acid and 5 to 15 parts by weight of a UV blocker together with a solvent and a photochromic compound are mixed with MMA resin to give an excellent effect on even concentration and color change of the photochromic compound and to be discolored by UV. Preventive effect, high UV protection and durability enhancement effect can be obtained.

Then, the mixed MMA resin was polymerized by primary polymerization at 70-90 ° C. for 20-40 minutes until constant viscosity, and then the secondary polymerization solution was put in a fixed mold in a water of about 50 ° C. The curing agent is added to 0.1 to 5 parts by weight based on 100 parts by weight of the MMA resin to cure for 3 to 4 hours. The steam is treated with steam at about 100 ° C. for 30 to 35 minutes. This process can obtain the effect of further increasing the strength.

After the polymerization process, the coating agent was added at about 75 ° C. for 10-15 seconds. Through this process, all of the photochromic compounds can be penetrated to a high concentration, and a product having excellent stability and durability can be made.

Therefore, the conventional MMA photochromic products were treated with a coating method, so the durability was remarkably decreased and the color change time was also very long. However, the photochromic acrylic resin according to the present invention is excellent in durability and remarkably fast in color change time. As a result, it is possible to produce the functional MMA resin desired by the consumer.

As described above, in the present invention, since the mixed organic solvent and the photochromic compound are liquefied together and uniformly mixed in the acrylic resin and then subjected to a polymerization process, the durability of the resin can be maintained, thereby making it possible to produce excellent products. That is, a molded article can be obtained through the process of polymerization 1 and polymerization 2 from the said method.

The molding may be manufactured by molding a variety of plate glass, windshield, optical lens, glasses, skylights, curtain boards, doors, signs, fluorescent lights, ornaments, jewelry, medical instruments, daily necessities, meter instruments or aircraft parts Its scope is not limited thereto.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the scope of the present invention is not limited to the following Examples.

Example 1

When 10 g of trichloroethane, 10 g of normal hexane and 15 g of methyl isobutyl ketone, 200 g of UV blocker, 5 g of photochromic compound YELLOW (Photochromic) and 1 g of 35% hydrochloric acid were mixed in a 500 L Henschel mixer. Mix evenly until. 1,000 g of MMA resin (MMA, LG Corp.) having a boiling point of about 80 ° C. was added to the mixture and mixed at 800 rpm for 25 minutes. This mixed solution was polymerized at about 80 ° C. for 30 minutes. Next, 2 g of a curing agent was added and placed in a fixed mold and cured in water of about 50 ° C. for 3 hours 30 minutes. After treatment for 35 minutes with steam at 100 ℃, the coating was added at about 75 ℃ for 15 seconds.

Example 2

The same procedure as in Example 1 was carried out except that 15 g of trichloroethane, 18 g of normal hexane, 20 g of methyl isobutyl ketone, 10 g of photochromic compound (VIOLET), and 2,000 g of MMA were added.

Comparative Example 1

The same procedure as in Example 1 was carried out except that MMA without mixing the photochromic compound was used.

Comparative Example 2

The same procedure as in Example 1 was carried out except that hydrochloric acid was not added during MMA mixing.

Comparative Example 3

MMA mixing was carried out in the same manner as in Example 1 except that 3 g of 35% hydrochloric acid was mixed.

When the acrylic resin was exposed to indoors and sunlight according to Examples 1 and 2 and Comparative Example 1, the discoloration rate and the degree of discoloration were determined by a sensory test, and according to the use of organic acids (hydrochloric acid) according to Comparative Examples 2 and 3, The results are shown in Table 1 below.

In addition, by using a daylight fastness measuring instrument at 45 ℃, 50% condition and using a UV lamp as a light source was determined by the sensory test discoloration rate and discoloration by UV irradiation and irradiation time and the results are shown in Table 1 below.

division Example 1 and Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 UV color Functionality (dark color change) Functionality (Color Change Moderate) Functionality (good color change) Destruction (no color change) MMA materials MMA Acrylic resin MMA MMA decolorization Good usually Good usually UV protection 95% 85% 97% 80% Reaction speed speed Slow speed Slow durability good usually good usually 1st polymerization time 30 minutes at 70 ℃ 1 hour at 75 ℃ 30 minutes at 70 ℃ 1 hour at 75 ℃ 2nd polymerization time 210 minutes in 50 ℃ water 4 hours at 50 ℃ water 210 minutes in 50 ℃ water 270 minutes in 50 ℃ water coating 15 seconds at 75 ° C 20 seconds at 80 ℃ 15 seconds at 75 ° C 20 seconds at 80 ℃ Steam 35 minutes at 100 ° C none 35 minutes at 100 ° C 35 minutes at 100 ° C

As described above, the method of the present invention uses a mixed organic solvent composed of normal hexane, trichloroethane and methyl isobutyl ketone as a solvent of the photochromic compound, and when mixing to a specific boiling point MMA resin, And through the polymerization process, the photochromic compound may be uniformly mixed in the MMA resin to express a uniform distribution and high concentration color and rapid color change (indoor: colorless or colored, outdoor: colored or colorless).

In addition, the method of the present invention by selecting the MMA and UV blocker as the main resin has an excellent effect of increasing durability, affinity, UV protection.

Claims (6)

It consists of 100 parts by weight of methyl methacrylate having a boiling point of 60 to 100 ° C, 0.1 to 5 parts by weight of normal hexane, 5 to 15 parts by weight of a UV blocker, 0.1 to 5 parts by weight of trichloroethane and 0.1 to 5 parts by weight of methyl isobutyl ketone. 0.01 to 0.2 part by weight of the organic acid and 0.1 to 1 part by weight of the photochromic compound are mixed with the mixed organic solvent, and then polymerized at 70 to 90 ° C. for 20 to 40 minutes, and 0.1 to 5 parts by weight of a curing agent is added thereto. Curing for 3 to 4 hours, and then treated with steam of about 100 ℃ for 30 to 35 minutes, and then containing a coating agent at about 75 ℃ to coat for 10 to 15 seconds, containing a photochromic compound Method for producing methyl methacrylate resin. The method of claim 1, wherein the photochromic compound is a naphthopyran-based compound. The method of claim 1, wherein the total amount of the mixed solvent is 0.5 to 10 parts by weight. The method of claim 1, wherein the organic acid is at least one selected from the group consisting of nitric acid, hydrochloric acid and sulfuric acid. The photochromic methylmethacrylate molding obtained from the method of any one of Claims 1-4. The molded article according to claim 5, wherein the molded article is made of various panes, windshields, optical lenses, glasses, skylights, curtain boards, doors, signs, fluorescent lamps, ornaments, jewelry, medical instruments, daily necessities, meter instruments or aircraft parts. Molded article characterized in that.