KR101806803B1 - Hard coating composition for spectacle lens not-containing organic solvent - Google Patents

Abstract

The present invention relates to a hard coating liquid composition, which comprises a polyether siloxane copolymer and at least one kind selected from the group consisting of acetylacetone and ethyl acetoacetate, to a product obtained by reacting with a silane coupling agent to an aqueous dispersion containing a metal- A viscosity control agent and a stabilizer. .

Description

TECHNICAL FIELD [0001] The present invention relates to a hard coating liquid composition for a spectacle lens containing no organic solvent,

The present invention relates to a hard coating liquid composition for a spectacle lens which does not contain an organic solvent. More specifically, it relates to a product obtained by reacting an aqueous dispersion containing a hydrated metal oxide compound with a silane coupling agent, a surface tension reducing agent such as a polyether (di) alkylpolysiloxane, and a viscosity and surface tension adjusting agent such as acetylacetone or ethyl acetoacetate Hard coating compositions.

Plastic lenses are widely used as a substitute for glass spectacle lenses because of their good light transmittance and good impact resistance. However, such a plastic lens has a weak disadvantage in the screw due to its low surface hardness, and it is essential to form a hard coating film on the surface of the lens in order to solve weak properties in such a screw.

A conventional conventional hard coating solution uses one or two types of hybrid silanes (silane coupling agents) for adhesion, and uses various inorganic oxide sols for strength and refractive index.

However, in order to use inorganic oxide sol, it is necessary to consider compatibility with selected silane coupling agent, pH, particle size, solid content, refractive index, hydrophilicity / It is very limited.

The silane coupling agent is hydrolyzed and condensed by a small amount of water in the course of the reaction to form a network structure, which is generated as a reaction product of organic alcohols, silanols, water and the like depending on each silane, . Since such an increase in viscosity affects the uniformity, thickness and physical properties of the coating film, solvents such as alcohol and cellulose are used in order to lower the viscosity and increase the curing rate. In consideration of the solvent of the inorganic oxide sol used together Is selected. There are two types of inorganic oxide sols, that is, an aqueous dispersion type and an organic solvent dispersion type. The particle size of the dispersion is in the range of about 20 to 80 nanometers. .

Inorganic metal oxide sols prepared at a low temperature by most of the sol-gel method have a property that when alcohol is used as a dispersion medium, water is easily gelled and hardened when water is present in excess. When water is used as a dispersion medium, , The stability of the liquid composition can be maintained and the composition component can be kept constant.

The finished hard coating solution is coated through a dip coating process and then cured to vaporize the solvent to form a final coating film.

Conventionally, in the hard coating liquid for a plastic lens, since the solvent is volatile with an alcohol such as methanol and the like, preparing and storing the hard coating liquid in advance increases the viscosity of the coating liquid with time, and is adjusted to a viscosity with alcohol such as methanol You must use it. In order to prevent volatilization and volatilization of the volatile hard coating liquid, it is very cumbersome and economical to use a hard coating liquid each time it is worked.

Furthermore, since solvents such as methanol are volatile, they are not only harmful to workers but also deteriorate the surrounding environment, and there is a danger of fire due to a low flash point during distribution and transportation, and air transportation is prohibited. Recently, Storage, or use of the product.

In the conventional technique, non-patent reference 1 described below discloses a method of producing a nano-sol from a metal oxide (Boehmite, AlOOH), adding a silane coupling agent, hydrolyzing and condensing the mixture, adding isopropyl alcohol, Is disclosed. That is, in Non-Patent Document 1, isopropyl alcohol is added to the surface-modified boehmite particles using a silane coupling agent to prepare a hard coating sol and used as a coating solution. Such a coating solution uses an isopropyl alcohol solvent, so that the hard coating solution is highly volatile and harmful to the human body.

Non-Patent Document 2 discloses a method of producing a hard coating solution from colloidal silica and a silane coupling agent by a sol-gel method. The content of this document is a method of preparing a hard coating solution by adding ethanol and water to a colloidal silica solution, making the solution acidic, adding silane coupling and stirring, and it is advantageous that methanol is not used, but ethanol is also volatile There is an inconvenience that the viscosity should be adjusted with ethanol every time the hard coating liquid is used, and the risk remains that the alcohol is used.

Patent Document 1 discloses a photocurable composition comprising an organic solvent inorganic conductive colloid of a polyfunctional acrylic monomer and an alcohol, and a radical photoinitiator, and discloses the use of such a composition in a hard coating. This patent literature also uses an alcohol such as methanol as an organic solvent, so that the above-mentioned problems are inherent.

Patent Document 2 discloses a water hard coating composition as a hard coating composition for use in a plastic sheet. However, the coating composition is used for a plastic sheet other than a plastic spectacle lens, and its composition is mostly composed of a polyfunctional acrylate, Colloidal silica, etc., and can not be used for hard coating of spectacle lenses.

Patent Document 1: Patent Document 10-2004-0051146 Patent Document 2: Patent Publication No. 10-2010-0037519

Non-Patent Document 1: J. Korean Ind. Eng. Chem. Vol. 6, December 2006, 2006, 580-585. Non-Patent Document 2: Korean Chem. Eng. Res., Vol. 45, No. 5, October, 2007, pp 442-447.

The coating solution of the hydrolysis / condensation reaction product of the sol solution of the inorganic oxide and the silane coupling agent on the surface of the plastic lens is considered to be harmful to the human body and contaminates the environment because the hard coating liquid composition containing the organic solvent which has been conventionally used is harmful to the human body Can not be achieved with conventional compositions and / or methods. Therefore, it is an object to easily adhere the coating liquid composition to the lens surface.

The present inventors have solved the above problem by using a sol of an aqueous metal oxide, using ionized water instead of an organic solvent, and using a surface tension reducing agent and a penetrating wetting agent to coat the surface of the plastic lens with the hydrolysis / condensation reaction product of the silane coupling agent . The present invention has been made by such a discovery.

Since the hard coating liquid composition of the present invention does not use an organic solvent, it is not harmful to the human body of the operator, and since the hard coating liquid is nonvolatile, there is no problem such that the viscosity increases with time in storage. Further, the hard coating liquid of the present invention has no problem in transportation and movement. Furthermore, the adhesion, scratch resistance and hardness of the hard coating film of the plastic lens formed using the hard coating liquid composition of the present invention are equal to or higher than those of the coating film formed using the conventional hard coating liquid. Therefore, the hard coating liquid composition of the present invention is industrially advantageous.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view for producing the hard coating liquid composition of the present invention. FIG.
FIG. 2 is a copy of a test report of a dangerous substance relating to the flash point of the hard coating liquid composition of the present invention described in Example 1. FIG.

The plastic spectacle lenses include CR-39 with a refractive index of 1.50, NK-55 (vinyl ester) with a refractive index of 1.56, urethane crab with a refractive index of 1.60, and polycarbonate and polymethylmethacrylate. Sunglasses, and optical lenses.

First, a hard coating liquid composition for a CR-39 lens having a refractive index of 1.50 will be described.

Generally, when water-soluble silica sol is used for environmental friendliness, various problems arise when using ionized water instead of organic solvent. Among them, the biggest problem is that since the amount of water is increased, the surface tension of the composition is increased, so that there is a coating failure problem in the immersion coating, so that the CT-39 lens is not coated or uniformly coated. In addition, since the organic solvent is not used, the curing rate is slowed, and problems such as scratch resistance are caused by excessive use of water, and it is contemplated to use ionized water instead of organic solvent.

In addition, silica sol is the only inorganic sol that can be applied to CR-39 having a refractive index of 1.50. In order to use silica sol of water-based type, compatibility with selected silane should be good in consideration of adhesion to lens surface, Particle size, dispersion stability, drying speed, and the like. For this reason, the conventional hard coating liquid for low refractive index has been produced by using an organic solvent such as methanol, isopropyl alcohol, ethyl cellosolve or the like at 20 to 40% (capacity) to lower the surface tension and viscosity and improve the drying speed.

In the present invention, alumina sol, which has higher refractive index and higher strength than silica sol, was used to adjust pH, water dispersibility, refractive index and strength so as to ideally blend with selected silane.

Means that the metal oxide compound of the sol-like metal oxide compound used in the present invention is one selected from the group consisting of alumina hydrate, boehmite, silica sol, zinc hydroxide, zirconium hydroxide and titanium hydroxide. These metal oxides having an average particle diameter of 50 nm or less are advantageous for forming a sol.

Of these metal oxides, particularly alumina sol, particularly Boehmite, is particularly preferable. The boehmite has an average particle diameter of 50 nm, in the form of a? -Crystalline phase, so that the dispersibility to water is very good and the dispersion stability And the scratch resistance is also equal to or higher than that of the existing metal oxide sol.

In case of alumina sol, it is used in the form of a sol dispersed in water. However, the sol dispersion may be dried under reduced pressure so as to be stored in a boehmite form so that it can be stored and stored for a long period of time.

In the present invention, alumina sol is obtained by using 6 to 10 times (weight) water of alumina powder. When the water content is lower than the lower limit value, the sol stability is deteriorated. Also, it is possible to form an alumina sol even if a larger amount of water than the upper limit value is used. However, the surface tension of the obtained hard coating liquid is increased and the amount of the surface tension reducing agent Do.

Examples of the silane coupling agent to be reacted with the aqueous dispersion containing the above-noted metal hydride compound include 3- (trimethoxysilyl) propyl methacrylate (MPTMS), (3-glycidylpropyl) trimethoxysilane (GPTMS) Phenyltrimethoxysilane (PYMS), vinyltriethoxysilane (VYES), and the like. Of these, (3-glycidylpropyl) trimethoxysilane (GPTMS) is particularly preferred.

The reaction of the silane coupling agent with the aqueous dispersion containing the above-described naphtha metal oxide compound is preferably carried out under an acidic condition, preferably at an acidic condition of pH 3.5 to 5.0, more preferably at a pH of 3.8 to 4.2 . Above pH 6, the sol phase began to change into a gel phase and could not maintain a stable state for long time coating. In addition, when the pH was adjusted to 3.0 or less, the hardness of the coating film tended to decrease, which was not preferable.

The amount of the silane coupling agent used is preferably 2.5 to 12 times the amount of the metal oxide.

Examples of the surface tension reducing agent used in the composition of the present invention include modified siloxanes such as polyether-modified, dimethylpolysiloxane, and polyether-modified diethylpolysiloxane. Such a surface tension reducing agent may be BYK-306, BYK-300, BYK-310 and other wetting agents commercially available from the present applicant.

Is also related to the amount of water used in the alumina sol solution. When the alumina sol solution is blended in an amount of 0.1 to 1.0 weight ratio with respect to the alumina sol solution obtained by using about 7 times (weight) water for alumina sol, the surface tension is favorably dropped, The hard coating liquid composition can be favorably adhered to the surface of the spectacle lens by the hydrolysis and condensation reaction of the alumina and the silane coupling agent.

The hard coating liquid composition of the present invention contains acetylacetone or ethylacetoacetate as a viscosity modifier and stabilizer. Although the present inventors have not been sure about the reaction mechanism of such a compound, the present inventors have found that, in the hydrolysis and condensation reaction of alumina sol and silane coupling agent, a part of the oxide part between these compounds acts as a ligand, .

The amount of these compounds to be used is suitably 0.2 to 0.8 parts by weight based on the total composition. When the amount is less than 0.2 part by weight, the function of viscosity adjustment is deteriorated. When the amount is more than 0.8 part by weight, it is confirmed that stability such as foam generation is slightly lowered.

The above is an example of application to CR-39 having a refractive index of 1.50, and for a lens having refractive index of 1.56 or more, titanium oxide sol or zinc oxide sol may be used in place of alumina sol. Other than the sol used, And the reaction is carried out. Accordingly, the description thereof will be omitted.

Hereinafter, the present invention will be described in more detail by way of examples. In the examples, water means pure water.

Example 1

At room temperature, 560 g of water was added to the reaction vessel, 80 g of AlOOH (average particle diameter of about 50 nm, type of γ-type crystal phase) was added, and while stirring for 2 hours, acetic acid was added to adjust the pH of the dispersion to 4. The reaction solution in the reaction tank is slightly bluish and stirred until it becomes transparent. While stirring the obtained reaction solution, 360 g of glycidoxypropyltrimethoxysilane (GPTMS) was slowly added thereto. The reaction is stirred for about 4 to 5 hours until the heat is completely exothermic. When the reaction was completed, 1.5 g of polyether-modified dimethylpolysiloxane and 5 g of acetylacetone (purification reagent grade reagent grade, purity of 99%) were added, and the mixture was further stirred for 1 hour.

A CR-30 lens was immersed in the hard coating solution obtained above, pre-cured at 80 DEG C for 10 minutes, and then cured at 120 DEG C for 2 hours to obtain a transparent coating film. The test results are shown in Table 1 below. In addition, the dangerous material test report of this hard coating liquid is referred to in Fig. 2 as a reference.

Example 2

At room temperature, 560 g of water was added to the reaction tank, 100 g of SiO ₂ powder and 15 g of acetic acid were added and stirred for 2 hours to disperse. While stirring the obtained reaction solution, 360 g of glycidoxypropyltrimethoxysilane (GPTMS) was slowly added thereto. The reaction is stirred for about 4 to 5 hours until the heat is completely exothermic. When the reaction is completed, 2 g of polyether-modified dimethylpolysiloxane and 10 g of acetylacetone (reagent grade reagent grade, purity 99%) are added. Stirring was continued for another hour.

An NK-55 lens (vinyl ester) was dip-coated on the hard coating solution obtained above, pre-cured at 80 DEG C for 10 minutes, and then cured at 120 DEG C for 2 hours to obtain a transparent coating film. The test results are shown in Table 1 below.

Example 3

At room temperature, 250 g of water was added to the reaction tank, 100 g of Ti (OH) ₄ powder and 15 g of acetic acid were added and stirred for 2 hours to disperse. While stirring the obtained reaction solution, 360 g of glycidoxypropyltrimethoxysilane (GPTMS) was slowly added thereto. The reaction is stirred for about 4 to 5 hours until the heat is completely exothermic. When the reaction is completed, 2 g of polyether-modified dimethylpolysiloxane and 10 g of acetylacetone (reagent grade reagent grade, purity 99%) are added. Stirring was continued for another hour.

An MR-8 (urethane) lens was immersed in the hard coating solution obtained above, preliminarily cured at 80 캜 for 10 minutes, and then cured at 120 캜 for 2 hours to obtain a transparent coating film. The test results are shown in Table 1 below.

Example 4

Except that Zr (OH) ₄ was used instead of Ti (OH) ₄ in Example 3. The test results are shown in Table 1 below.

Comparative Example 1

300 g of colloidal silica (Nanos LS, manufactured by ABC Nattech Co., Ltd., Nanos LS), 20 g of acetic acid, 280 g of GPTMS and 70 g of water were added to the reaction vessel at room temperature. After completion of the reaction by stirring for 4 hours, 150 g of methanol, 80 g of ethylcellosol, Propyl alcohol, and 1 g of polyether siloxane copolymer was added thereto, followed by further stirring for 1 hour to obtain a hard coating solution.

The CR-39 lens was immersed in the hard coating liquid obtained above, pre-cured at 80 DEG C for 10 minutes, and cured at 120 DEG C for 2 hours to obtain a transparent coating film.

The test results are shown in Table 1 below.

Comparative Example 2

250 g of water-soluble colloidal silica (catalytic property, Colloid-S), 30 g of acetic acid, 280 g of GPTMS and 80 g of methacryloxypropyltrimethoxysilane were added to the reaction tank at room temperature, and the reaction was completed by stirring for 4 hours, , 80 g of ethyl cellosolve and 100 g of isopropyl alcohol, 1 g of polyether siloxane copolymer was added, and the mixture was further stirred for one hour to obtain a hard coating solution.

The CR-39 lens was immersed in the hard coating liquid obtained above, pre-cured at 80 DEG C for 10 minutes, and cured at 120 DEG C for 2 hours to obtain a transparent coating film.

The test results are shown in Table 1 below.

Comparative Example 3

The hard coating solution obtained in Comparative Example 1 was stored at room temperature (15 to 25 ° C) for 15 days, and it was tried to be used as a hard coating, but it could not be used due to viscosity increase of the coating solution. Thus, when 60 g of methanol was added and used, results similar to those of Comparative Example 1 were obtained.

Comparative Example 4

The hard coating solution obtained in Comparative Example 1 was stored at room temperature (15 to 25 ° C) for 50 days. When the hard coating solution was observed, methanol was volatilized and the coating solution was in a gel state.

<How to measure>

1) Adhesion test: A checkerboard was cut with a cutter on a cured coating layer according to ASTM D3359, and then a vertical tape (OPP) was closely adhered and peeled off several times with a constant force to observe the degree of adhesion between the coating layer and the substrate. A square was cut out in a cross shape at 11 mm intervals at intervals of 1 mm to make 100 squares. A vertical tape (3M tape) was attached thereon, and the surface was rapidly pulled to evaluate the surface. 5B for the remaining 100, 4B for the 95 or more, 3B for the 85 or more, 2B for the 65 or more, 1B for the 35 or more, and 0B for the remaining.

2) Scratch resistance test: After making 10 reciprocations with 1 kg load using # 0000 steel wool, observe the surface condition.

⊙: No abnormal surface

○: Some scratches on the surface

?: Large surface scratches

3) Pencil hardness: A pencil was placed on a pencil hardness tester (221-D, Mitsubishi pencil hardness tester) and measured while drawing a line with a load of 1 kg. Change the pencil until surface scratches occur.

4) Boiling water test: Immerse the coated lens in 96 ° C ~ 98 ° C water for 10 minutes, check for surface cracks, and then perform adhesion test as in 1).

5) Drying condition after preliminary curing: 80 ° C / 10-20 minutes After curing, there should be no tackiness of coating film or remarkable fingerprints.

○: No sticky surface, no fingerprints

△: The surface has no stickiness, but some fingerprints are present

X: The surface is sticky, and the fingerprints are present

6) Film Thickness: The thickness of the film is measured using a micrometer.

7) A hard coating solution was prepared, and the change in the total volume of the coating solution after 7 days was measured. The results were evaluated according to the following ratings.

1: When the displacement capacity is 1% or less.

2. When the displacement capacity is less than 3%.

3. When the displacement capacity is more than 10%.

4. When the displacement capacity is 20% or more. ,

Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Comparative Example 3 Contact Force Test 5B 5B 5B 5B 5B 5B 5B Scratch resistance ⊙ ⊙ ⊙ ⊙ ○ ○ ○ Pencil hardness 2H 3H 3H 3H 3H 2H 2H Film thickness
(탆) 3.4 3.2 2.8 2.8 2.4 2.5 2.6 Boiling water
exam 5B 5B 5B 5B 5B 5B 5B Dry after pre-curing ○ ○ ○ ○ ○ ○ ○ Viscosity (cps) 6 7 7 6 8 7 8 Capacity change One One One One 3 3 3

As shown in Table 1, the hard coating liquid of the present invention is excellent in adhesion, scratch resistance is equivalent to or higher than that of a conventional hard coating liquid, and pencil hardness is excellent. Further, since the hard coating liquid of the present invention does not use an organic solvent such as alcohol, it shows almost no change in capacity even after storage for a long time and is safe for handling.

Claims (9)

With the hard coating liquid composition,
Dispersing the sol-like metal oxide compound in water to obtain an aqueous dispersion,
Adding a surface tension reducing agent and a penetrating wetting agent to a product obtained by hydrolyzing and condensing the aqueous dispersion obtained above with a silane coupling agent, and stirring and aging,
A hard coating composition comprising a product obtained by reacting a water dispersion containing a metal oxide compound with a silane coupling agent at a pH of 4.5 to 5.5. The hard coating according to claim 1, wherein the metal oxide compound of the sol-like metal oxide compound is one selected from the group consisting of alumina hydrate, boehmite, colloidal silica, zinc hydroxide, zirconium hydroxide and titanium hydroxide. Composition. The hard coating composition according to claim 1, wherein the silane coupling agent is glycidoxypropyltrimethoxysilane. The hard coating composition of claim 1, wherein the hard coating liquid composition further comprises a viscosity adjusting and stabilizing agent, wherein the viscosity adjusting and stabilizing agent is acetylacetone and the surface tension reducing agent is a polyether siloxane copolymer. The hard coating composition according to claim 1, wherein the penetrating wetting agent is one or two selected from the group consisting of acetylacetone and ethyl acetoacetate. The method according to any one of claims 1 to 5,
Wherein the average particle diameter of the metal oxide compound is 40 to 80 nm or less. The method according to any one of claims 1 to 5,
Wherein the metal oxide sol is dispersed in water by 5 to 25 times by weight with respect to the metal oxide sol. delete The hard-coating composition according to claim 1 or 2, wherein the reaction ratio of the metal oxide to the silane coupling agent is 2.5 to 8 times.

Images