KR102522289B1 - Method for injecting thiourethane based monomer in mold for manufacturing optical material - Google Patents

Abstract

The present invention relates to a method for manufacturing an optical material by injecting a thiourethane-based monomer solution into a cavity formed between a pair of sealed molds, and more particularly, to a vision recognition system while injecting a thiourethane-based monomer solution into the cavity. It relates to a mold automatic injection method of a monomer for thiourethane-based optical materials that enables quantitative injection within a short time by using. In the present invention, (a) preparing a monomer composition for a thiourethane-based optical material having a solid refractive index of 1.523 to 1.690 and a viscosity of 20 to 1,000cps (25° C.); (b) injecting most of the monomer composition into a cavity formed between a pair of molds whose outer edges are sealed; (c) terminating the injection of the monomer composition when the oil level is sensed at the set final injection point by detecting the oil level using a vision recognition system while injecting the monomer composition into the cavity following the step (b); A method for automatically injecting a monomer for a urethane-based optical material into a mold is provided. According to the present invention, it is possible to automatically inject the monomer solution for thiourethane-based optical materials into the mold in a fixed amount without running out or overflowing.

Description

Method for injecting thiourethane based monomer in mold for manufacturing optical material}

The present invention relates to a method for manufacturing an optical material by injecting a thiourethane-based monomer solution into a cavity formed between a pair of sealed molds, and more particularly, to a vision recognition system while injecting a thiourethane-based monomer solution into the cavity. It relates to a mold automatic injection method of a monomer for thiourethane-based optical materials that enables quantitative injection within a short time by using.

In optical materials, plastic lenses are lighter than glass lenses, do not break easily, and have advantages in processability, so plastic lenses are used more often than glass lenses in recent years. Such a plastic lens is manufactured by injecting a polymer compound called a monomer into a mold, hardening it, and then performing appropriate post-processing. That is, it is manufactured by injecting a monomer solution into a mold having a lens-shaped empty injection space (cavity).

As a prior art related to this, 'apparatus for setting the moving distance of a mold for manufacturing spectacle lenses' of Patent Document 1 is disclosed.

In Patent Document 1, in order to accurately determine the separation distance of glass molds for manufacturing spectacle lenses, the glass molds are spaced apart from each other using a mold chuck, and a tape is adhered to the outer circumferential surface of the glass mold, and a monomer is attached to the glass mold after the taping operation is completed. A method of manually injecting the solution is introduced.

However, since the technique of manually injecting a monomer into a glass mold as disclosed in Patent Document 1 is entirely dependent on the skill level of the injector, defects may occur depending on the skill level and work efficiency may be reduced. In particular, since it requires a lot of skill to precisely inject the monomer in a certain amount every time, there is a problem that bubbles may occur inside the mold in the case of unskilled users.

In addition, since the liquid monomer generates volatile gases harmful to the human body, it may adversely affect the health of workers when working for a long time.

Thiourethane-based optical materials are widely used as optical lens materials because of their excellent optical properties such as transparency, Abbe number, transmittance, and tensile strength. In Korean Registered Patent Nos. 10-0136698, 10-0051275, 10-0051939, 10-0056025, 10-0040546, and 10-0113627, a polyisocyanate compound and a polythiol compound are thermally cured to prepare a thiourethane-based optical lens. Reduction of production cost is one of the major concerns in the field of optical lenses including thiourethane-based optical materials. If automatic injection is possible in an automatic production facility without human hands, productivity can be improved as well as the problem of harmfulness to the human body during the production process can be solved, but injection automation is still difficult despite many attempts. This is also caused by the high viscosity of the monomer composition and the difference in viscosity and pot life according to the composition.

Patent Document 2 (Korean Patent Registration No. 10-1383132) discloses 'an automatic monomer injection equipment for spectacle lenses and a method for producing spectacle lenses using the same'. In Patent Document 2, in the step of injecting a monomer solution into the cavity formed by a pair of molds, the position of the lens mold is grasped by using a displacement sensor (laser sensor) that detects the position of the lens mold, and the second movement is performed. The level of the raw material filled in the lens mold is sensed by the unit, and the amount of monomer injection of the injection nozzle is controlled by the injection amount control unit. It is set to be adjusted in 2 steps, 10mm.

However, when detecting the water level of the raw material (monomer composition) using a displacement sensor as in Patent Document 2, the monomer composition is more viscous than water, so that the change in water level is not a horizontal change, but a two-dimensional symmetrical parabola. As a result, there was a problem in that it was difficult to accurately detect the water level in real time, and because of this, it was difficult to inject in an accurate amount despite step-by-step control of the injection amount, resulting in insufficient or excessive injection amount, leading to product failure or overflowing of the monomer. The composition could contaminate injection equipment.

In addition, in 'Plastic Product Manufacturing Method and Manufacturing Apparatus' of Patent Document 3 (Japanese Patent Registration No. 3707189), as a method for automating the process of injecting a plastic stock solution into a molding mold in the plastic lens manufacturing process, The first step is to measure the width between the first and second walls to set the first flow rate and the first time, and inject the plastic stock solution into the cavity at the first flow rate for the first time, followed by the first step to the cavity. Reducing the injection time by injecting the stock solution at a large flow rate for a predetermined period of time by injecting the stock solution at a high flow rate and then injecting the stock solution at a low volume toward the end of the injection by having a second process of injecting the plastic stock solution at a second flow rate smaller than the flow rate At the same time, the amount of leakage is reduced.

However, in the injection method according to Patent Document 3, the injection amount and injection time of the plastic raw material are reduced step by step in consideration of the spatial characteristics of the cavity, thereby shortening the injection time and reducing the amount of leakage, but injecting the monomer into the mold. Since the oil level change characteristics of the highly viscous monomer solution are not taken into account, leak defects still occur and metered injection is difficult.

In Patent Document 4 (Japanese Unexamined Patent Publication No. 2007-80766), when injecting the liquid molding material into the mold in the same way as pouring alcohol by tilting a glass, in the 'method of forming a plastic lens,' do not leave bubbles as much as possible inside. Initially, the injection is started by making the injection port slightly deviate from the upper center to one side so that the injection port is slightly deviated from the upper center to one side, and when the injection progresses to a certain extent, the mold is rotated (tilted) so that the injection port is located in the upper center to charge the raw material monomer A method for molding a plastic lens is disclosed.

However, Patent Document 4 is a suitable method for injecting the raw material so that bubbles do not remain, but there was still difficulty in injecting the raw material in an accurate amount.

1. Republic of Korea Utility Model Registration No. 20-0236704 2. Republic of Korea Patent No. 10-1383132 3. Japanese Patent Registration No. 3707189 4. Japanese Patent Laid-Open No. 2007-80766 5. Korean Registered Patent Publication No. 10-0136698 6. Korean Registered Patent Publication No. 10-0051275 7. Korean Registered Patent Publication No. 10-0051939 8. Korean Registered Patent Publication No. 10-0056025 9. Korean Registered Patent Publication No. 10-0040546

As described above, many prior arts have proposed methods for automatically injecting monomers for optical materials into molds, but it is difficult to inject the monomers in an accurate amount without overflow or shortage. In addition, there are differences in the curing speed and curing time for each monomer, the difference in viscosity, the difference in oil level, and the composition even in the same series of monomers. There is a problem in that it is difficult to accurately inject because it cannot respond to the difference according to the method.

The present invention has been made to solve the above problems, and an object of the present invention is to automatically inject the monomer composition for thiourethane-based optical materials into a mold, which can accurately inject the monomer composition for thiourethane-based optical materials into a mold without insufficient or excessive injection amount. is to provide a way

In particular, the present invention divides and injects the monomer composition for thiourethane-based optical materials into the cavity of the mold in two steps, injects most of it in the first step, and then uses a vision recognition system in the second step to check the oil level of the thiourethane-based monomer solution. When the oil level is detected at the final injection point, the injection is stopped to reduce the injection time and to provide an automatic mold injection method for monomer for thiourethane-based optical materials, which can inject a constant amount so that the monomer solution is not overflowed or insufficient. There is a purpose.

In order to achieve the above object, the present invention,

As a method of injecting a monomer composition for a thiourethane-based optical material into a cavity formed between a pair of molds sealed on the outside,

(a) preparing a monomer composition for a thiourethane-based optical material having a solid refractive index of 1.523 to 1.690 and a viscosity of 20 to 1,000cps (25° C.);

(b) injecting a majority of the monomer composition into the cavity;

(c) terminating the injection of the monomer composition when the oil level is sensed at the set final injection point by detecting the oil level using a vision recognition system while injecting the monomer composition into the cavity following the step (b); A method for automatically injecting a monomer for a urethane-based optical material into a mold is provided.

In the step (b), the monomer composition may be injected into the cavity by a predetermined weight or volume, or may be injected into a predetermined area within the mold using a vision recognition system.

The vision recognition system photographs the contour of the mold and the oil level of the monomer solution injected into the mold, and detects the state in which the mold is set at the injection position. It is possible to set the second area where it is located.

In the vision recognition system in which the first and second regions are set as described above, preferably, when the controller detects the outline of the mold in the first region, most of the monomer solution is injected into the mold with the set first injection pressure, and then When the oil level is detected in the second area while injecting the residual amount of the monomer solution at a pressure lower than the first injection pressure, the injection of the monomer solution is terminated.

In the first and second regions, the outline of the mold and the oil level of the monomer solution are preferably sensed by a change in the number of pixels.

In a preferred embodiment of the present invention, a virtual contour is displayed in the form of an arc in the first area, and when the mold contour is detected in the first area, the photographing position is adjusted so that the mold contour captured matches the virtual contour. , The position of the second region is moved along with the change in the position of the first region to detect a change in oil level.

In a preferred embodiment, the first region means a position having both X-direction information and Y-direction information of the mold, that is, in a diagonal direction among the outer edges of the mold. The first area is a reference for position movement of the second area, and in the first area, when the mold is seated at the injection position, the contour of the mold is sensed immediately.

In a preferred embodiment, the second region is set outside a position close to the monomer inlet of the mold in order to fill the cavity inside the mold with the monomer solution without bubbles, and is generally installed at a position within 1 to 2 mm from the contour of the mold. .

In a preferred embodiment, the controller injects 70 to 99% of the monomer solution at a high pressure, that is, at a high speed, and slowly injects the remaining amount at a low pressure when the monomer solution initially injected into the syringe is injected into the mold. Controls the syringe driving unit.

The monomer composition for the thiourethane-based optical material includes a polythiol compound and a polyisocyanate compound.

The monomer composition for the thiourethane-based optical material may further include an internal release agent, if necessary.

Preferably, the injection of the monomer composition is made in the temperature range of 5 ~ 60 ℃.

According to the present invention, when the monomer for thiourethane-based optical materials is injected into the mold, the injection is automatically stopped when the final injection point is reached while checking the oil level using a vision recognition system, so that the monomer solution is neither insufficient nor overflowing. possible.

In addition, since it is injected while checking the oil level using a vision recognition system when injecting the remaining amount, rather than simply adjusting the injection amount or speed mechanically, constant injection is possible regardless of the difference in viscosity or shape of the oil level depending on the monomer.

In addition, since the injection time of the monomer can be shortened by first rapidly injecting most of the monomer into the cavity inside the mold, it is easy to set the injection to be completed within the pot life determined in advance, and thus curing according to the monomer Regardless of the difference in speed and curing time, constant injection is possible in an optimal state before curing.

According to the present invention, since high-quality thiourethane-based lenses can be produced by automatic injection without defects due to insufficient or excessive injection amount, productivity can be greatly improved and production costs can be reduced by reducing labor costs. Abnormal operation or failure of equipment due to direct exposure and excessive injection of the monomer composition can also be prevented.

1 is a flowchart schematically showing a lens manufacturing process according to an embodiment of the present invention;
2 is a block diagram of an automatic monomer injection method according to an embodiment of the present invention;
3 is a state in which the monomer solution in FIG. 2 is first sucked into the syringe;
4 is a state in which the monomer solution is injected into the mold in FIG. 3;
FIG. 5 shows a state in which the inside of the mold is filled with the monomer solution in FIG. 4 .

Hereinafter, a method for automatically injecting a mold for a thiourethane-based optical material monomer according to the present invention will be described step by step according to preferred embodiments.

The method of automatically injecting a mold for a thiourethane-based optical material monomer of the present invention,

(a) preparing a monomer composition for a thiourethane-based optical material having a solid refractive index of 1.523 to 1.690 and a viscosity of 20 to 1,000cps (25° C.);

(b) injecting most of the monomer composition into a cavity formed between a pair of molds whose outer edges are sealed;

(c) following step (b), while injecting the monomer composition into the cavity, detecting the oil level using a vision recognition system, and terminating the injection of the monomer composition when the oil level is detected at the set final injection point; includes.

The monomer composition for the thiourethane-based optical material is meant to include both a composition including a polythiol compound and a polyiso(thio)cyanate compound or a prepolymer thereof. In the present invention, 'monomer solution' refers to the case where the monomer composition is in a liquid state with fluidity.

The monomer composition for thiourethane-based optical materials has a solid refractive index of 1.523 to 1.690 and a viscosity of 20 to 1,000cps at 25°C. More preferably, the viscosity is 30 to 500cps at 25°C.

The polyisocyanate compound is preferably isophorone diisocyanate, dicyclohexylmethane-4,4-diisocyanate (H ₁₂ MDI), hexamethylene diisocyanate, methylcyclohexane diisocyanate, tolylene diisocyanate, phenylene diisocyanate, 1,3,5-tris(6-isocyanato-hexyl)-[1,3,5]-trizianane-2,4,6-trione (HDI trimer), o,m,p-xylyl One or two or more polyisocyanates selected from the group consisting of rendiisocyanate (o,m,p-xylylenediisocyanate) and tetramethylxylylenediisocyanate (TMXDI) may be used alone or together. The polyisocyanate compound may preferably be a general-purpose isocyanate compound supplied at low cost.

The monomer composition of the present invention may further contain one or two or more other iso(thio)cyanate compounds in addition to the above isocyanate. Examples of such iso(thio)cyanate compounds include 2,2-dimethylpentane diisocyanate, 2,2,4-trimethylhexane diisocyanate, butene diisocyanate, 1,3-butadiene-1,4-diisocyanate, 2, 4,4-trimethylhexamethylene diisocyanate, 1,6,11-undecatriisocyanate, 1,3,6-hexamethylenetriisocyanate, 1,8-diisocyanate-4-isocyanatomethyloctane, bis(iso aliphatic isocyanate compounds including cyanatoethyl)carbonate and bis(isocyanatoethyl)ether;

1,2-bis(isocyanatomethyl)cyclohexane, 1,3-bis(isocyanatomethyl)cyclohexane, 1,4-bis(isocyanatomethyl)cyclohexane, cyclohexane diisocyanate, alicyclic isocyanate compounds including methylcyclohexane diisocyanate, dicyclohexyldimethylmethane isocyanate, and 2,2-dimethyldicyclohexylmethane isocyanate;

Bis(isocyanatobutyl)benzene, bis(isocyanatomethyl)naphthalene, bis(isocyanatomethyl)diphenyl ether, phenylene diisocyanate, ethylphenylene diisocyanate, isopropylphenylene diisocyanate, dimethylphenylene di Isocyanate, diethylphenylene diisocyanate, diisopropylphenylene diisocyanate, trimethylbenzene triisocyanate, benzene triisocyanate, biphenyl diisocyanate, toluidine diisocyanate, 4,4-diphenylmethane diisocyanate, 3,3-dimethyldiphenyl Methane-4,4-diisocyanate, bibenzyl-4,4-diisocyanate, bis(isocyanatophenyl)ethylene, 3,3-dimethoxybiphenyl-4,4-diisocyanate, hexahydrobenzene diisocyanate , Aromatic isocyanate compounds including hexahydrodiphenylmethane-4,4-diisocyanate;

Bis(isocyanatoethyl)sulfide, bis(isocyanatopropyl)sulfide, bis(isocyanatohexyl)sulfide, bis(isocyanatomethyl)sulfone, bis(isocyanatomethyl ) disulfide, bis(isocyanatopropyl)disulfide, bis(isocyanatomethylthio)methane, bis(isocyanatoethylthio)methane, bis(isocyanatoethylthio)ethane, bis( sulfur-containing aliphatic isocyanate compounds including isocyanatomethylthio)ethane, 1,5-diisocyanato-2-isocyanatomethyl-3-thiapentane;

Diphenylsulfide-2,4-diisocyanate, diphenylsulfide-4,4-diisocyanate, 3,3-dimethoxy-4,4-diisocyanatodibenzylthioether, bis(4-isocyanate) Itomethylbenzene) sulfide, 4,4-methoxybenzenethioethylene glycol-3,3-diisocyanate, diphenyldisulfide-4,4-diisocyanate, 2,2-dimethyldiphenyldisulfide-5,5 -Diisocyanate, 3,3-dimethyldiphenyldisulfide-5,5-diisocyanate, 3,3-dimethyldiphenyldisulfide-6,6-diisocyanate, 4,4-dimethyldiphenyldisulfide-5, sulfur-containing aromatic isocyanate compounds including 5-diisocyanate, 3,3-dimethoxydiphenyldisulfide-4,4-diisocyanate, and 4,4-dimethoxydiphenyldisulfide-3,3-diisocyanate; and

2,5-diisocyanatothiophene, 2,5-bis(isocyanatomethyl)thiophene, 2,5-diisocyanatotetrahydrothiophene, 2,5-bis(isocyanatomethyl) Tetrahydrothiophene, 3,4-bis(isocyanatomethyl)tetrahydrothiophene, 2,5-diisocyanato-1,4-dithiane, 2,5-bis(isocyanatomethyl) -1,4-dithiane, 4,5-diisocyanato-1,3-dithiolane, 4,5-bis(isocyanatomethyl)-1,3-dithiolane, 4,5-bis( One or two or more iso(thio)cyanate compounds selected from the group consisting of sulfur-containing heterocyclic isocyanate compounds including isocyanatomethyl)-2-methyl-1,3-dithiolane may be used.

The polythiol compound is not particularly limited, and a compound having two or more thiol groups in one molecule may be used. For example, the polythiol compound is 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane, 2,3-bis(2-mercaptoethylthio)-3-propane-1 -thiol, 2,2-bis(mercaptomethyl)-1,3-propanedithiol, bis(2-mercaptoethyl)sulfide, tetrakis(mercaptomethyl)methane; 2-(2-mercaptoethylthio)propane-1,3-dithiol, 2-(2,3-bis(2-mercaptoethylthio)propylthio)ethanethiol, bis(2,3-dimercapto Propanyl) sulfide, bis(2,3-dimercaptopropanyl)disulfide, 1,2-bis(2-mercaptoethylthio)-3-mercaptopropane, 1,2-bis(2-(2- Mercaptoethylthio)-3-mercaptopropylthio)ethane, bis(2-(2-mercaptoethylthio)-3-mercaptopropyl)sulfide, 2-(2-mercaptoethylthio)-3-2 -Mercapto-3-[3-mercapto-2-(2-mercaptoethylthio)-propylthio]propylthio-propane-1-thiol, 2,2-bis-(3-mercapto-propionyloxy) Methyl)-butyl ester, 2-(2-mercaptoethylthio)-3-(2-(2-[3-mercapto-2-(2-mercaptoethylthio)-propylthio]ethylthio)ethylthio ) Propane-1-thiol, (4R,11S)-4,11-bis(mercaptomethyl)-3,6,9,12-tetrathiatetradecane-1,14-dithiol, (S)-3- ((R-2,3-dimercaptopropyl)thio)propane-1,2-dithiol, (4R,14R)-4,14-bis(mercaptomethyl)-3,6,9,12,15 -pentathiaheptane-1,17-dithiol, (S)-3-((R-3-mercapto-2-((2-mercaptoethyl)thio)propyl)thio)propyl)thio)-2- ((2-mercaptoethyl)thio)propane-1-thiol, 3,3'-dithiobis(propane-1,2-dithiol), (7R,11S)-7,11-bis(mercaptomethyl) -3,6,9,12,15-pentatierheptane-1,17-dithiol, (7R,12S)-7,12-bis(mercaptomethyl)-3,6,9,10,13,16 -Hexathiaoctadecane-1,18-dithiol, 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4,7-dimercaptomethyl- 1,11-dimercapto-3,6,9-trithiaundecane, 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, pentaerythritol Tetrakis(3-mercaptopropionate), trimethylolpropane tris(3-mercaptopropionate), pentaerythritoltetrakis(2-mercaptoacetate), bispentaerythritol-ether-hexakis (3-mercaptopropionate), 1,1,3,3-tetrakis(mercaptomethylthio)propane, 1,1,2,2-tetrakis(mercaptomethylthio)ethane, 4,6- One or two or more selected from the group consisting of bis(mercaptomethylthio)-1,3-dithiane and 2-(2,2-bis(mercaptodimethylthio)ethyl)-1,3-dithiane it is a compound Preferably, the polythiol compound is 2-(2-mercaptoethylthio)propane-1,3-dithiol; 2,3-bis(2-mercaptoethylthio)propane-1-thiol; 2-(2,3-bis(2-mercaptoethylthio)propylthio)ethanethiol; 1,2-bis(2-mercaptoethylthio)-3-mercaptopropane; 1,2-bis(2-(2-mercaptoethylthio)-3-mercaptopropylthio)-ethane; bis(2-(2-mercaptoethylthio)-3-mercaptopropyl)sulfide; 2-(2-mercaptoethylthio)-3-2-mercapto-3-[3-mercapto-2-(2-mercaptoethylthio)-propylthio]propylthio-propane-1-thiol; 2,2'-thiodiethanethiol, 4,14-bis(mercaptomethyl)-3,6,9,12,15-pentathiahexadecane-1,17-dithiol, 2-(2-mercapto Ethylthio)-3-[4-(1-{4-[3-mercapto-2-(2-mercaptoethylthio)-propoxy]-phenyl}-1-methylethyl)-phenoxy]-propane -1-thiol, pentaerythritol tetrakis (3-mefcaptopropionate), pentaerythritol mefcaptoacetate, trimethyolpropanetrismefcaptopropionate, glycerol trimepcaptopropionate, dipentaepyte Compounds such as ritolhexamecaptopropionate may be used alone or in combination of two or more thereof, and in addition, compounds in which some of these unreacted hydroxyl groups are mixed may be included.

The monomer composition for the thiourethane-based optical material may further contain optional components such as a polymerization catalyst, an internal release agent, an ultraviolet absorber, a dye, a stabilizer, a bluing agent, a crosslinking agent, a light stabilizer, an antioxidant, and a filler, if necessary. there is.

As the internal release agent, a phosphoric acid ester compound, a silicone-based surfactant, a fluorine-based surfactant, etc. may be used alone or in combination of two or more. Preferably, a phosphoric acid ester compound is used as an internal release agent. The phosphoric acid ester compound is prepared by adding 2 to 3 moles of an alcohol compound to phosphorus pentoxide (P ₂ O ₅ ). At this time, there may be various types of acidic phosphoric acid ester compounds depending on the type of alcohol used. Representative examples are types in which ethylene oxide or propylene oxide is added to an aliphatic alcohol, or ethylene oxide or propylene oxide is added to a nonylphenol group. When an acidic phosphoric acid ester compound to which ethylene oxide or propylene oxide is added is included in the polymerizable composition of the present invention as an internal release agent, it is preferable to obtain an optical material having good release properties and excellent quality. The phosphoric acid ester compound used as the internal mold release agent is preferably polyoxyethylene nonylphenol ether phosphate (5% by weight of 5 moles of ethylene oxide added, 80% by weight of 4 moles added, 10 weight% by weight of 3 moles added) %, 5% by weight added by 1 mol), polyoxyethylene nonylphenol ether phosphate (3% by weight added by 9 mol of ethylene oxide, 80% by weight added by 8 mol, 5% by weight added by 9 mol, 7 mol added 6 wt%, 6 mol added 6 wt%), polyoxyethylene nonylphenol ether phosphate (ethylene oxide 13 mol added 3 wt%, 12 mol added 80 wt%, 11 mol added 8% by weight added, 3% by weight added with 9 moles, 6% added with 4 moles), polyoxyethylene nonylphenol ether phosphate (3% by weight added with 17 moles of ethylene oxide, added with 16 moles) 79% by weight, 10% by weight added by 15 moles, 4% by weight added by 14 moles, 4% by weight added by 13 moles), polyoxyethylene nonylphenol ether phosphate (5% by weight added by 21 moles of ethylene oxide) %, 76% by weight added by 20 moles, 7% by weight added by 19 moles, 6% by weight added by 18 moles, 4% by weight added by 17 moles), Ethylene such as Zelec UN™ An acidic phosphate ester compound to which oxide or propylene oxide is added may be used alone or in combination of two or more. The internal release agent is preferably included in an amount of 0.001 to 10% by weight in the total monomer composition.

The injection of the monomer composition is preferably performed in a temperature range of 5 to 60°C. More preferably it can be made in the temperature range of 21 ~ 40 ℃. By injecting at an appropriate temperature, pot life can be appropriately maintained, and finally, a high-quality optical material without striae or white turbidity and colorless transparency without deformation can be obtained. Especially preferably, when the injection temperature was in the range of 28 to 36 ° C, the highest quality high refractive polyurethane optical lens could be manufactured.

In the step (b), the monomer composition may be injected into the cavity by a predetermined weight or volume, or may be injected into a predetermined area within the mold using a vision recognition system. In the step (c), the injection of the monomer composition is terminated when the oil level is detected at the final injection point set by detecting the oil level using the vision recognition system.

Hereinafter, preferred embodiments of the steps (b) and (c) will be described with reference to the accompanying drawings.

First, as shown in FIG. 1, a method of automatically injecting a monomer solution into a mold to manufacture an optical material such as a lens is mold loading (S10), taping (S20), tape opening (S30), monomer injection ( S40), tape closure (S50), and mold unloading (S60). As a subsequent process, the lens is completed by curing the monomer and then separating it from the mold. This process is basically the same as the existing method. do.

In this embodiment, while injecting the monomer in the raw material tank into the cavity of the mold, a vision recognition system is used to detect the oil level, and when the oil level is detected at the set final injection point, a specific method of stopping the injection of the monomer solution is proposed. As shown in FIGS. 2 to 5, after the monomer solution (S) in the monomer solution tank (10) is primarily sucked into the syringe (20) whose capacity can be adjusted according to the cavity of the mold (M), the syringe (20) ) Inject the monomer solution (S) injected into the inside of the mold (M) secondly at high speed, inject the remaining amount by lowering the injection pressure, and finally use the vision recognition system to inject the monomer solution (S) After confirming that the inside of the mold (M) is filled, the injection is terminated.

In this embodiment, the vision recognition system, as can be seen in Figures 2 to 5, the outline of the mold (M) and the oil surface (L1) of the monomer solution (S) injected into the cavity of the mold (M) , A first area (A1) of a part of the contour of the mold (M) for detecting the state in which the mold (M) is set at the injection position and a second area (A2) located outside the injection hole of the mold (M) are set has been

On the other hand, when the controller C detects the image signal captured by the vision recognition system, that is, the outline of the mold M in the first area A1 as shown in FIG. 2, the mold M is positioned at the injection position. It is recognized as being seated. At this time, it is determined whether the contour of the mold (M) photographed and the virtual contour (L) displayed in the form of an arc in the first area (A1) match, and if they do not match, the vision recognition system Fine adjustment, that is, a photographing position adjustment step of matching the virtual contour (L) to the contour of the mold (M) by adjusting the position of the vision camera is performed.

In the above-described photographing position adjustment step, the position of the first area A1 is adjusted and the position of the second area is moved equidistantly along with the first area A1 at the same time, so that the seating position of the mold M in the injection device Despite the slight change in , the second area A2 photographed by the vision recognition system detects a change in the oil level of the monomer solution by photographing the same location.

In addition, the controller (C) analyzes the image taken by the vision recognition system to determine the capacity of the cavity and detects whether or not the injection position is set according to the type of mold (M), and the driver 22 of the syringe 20 and the valve ( By controlling the opening and closing operation of V), as shown in FIG. 3, the amount of primary inhalation of the monomer solution (S) into the syringe 20, the time of second injection into the mold (M), the injection pressure, and the end time It controls and also adjusts the fine position of the vision recognition system.

In addition, the controller (C) sets the injection pressure differently according to the type of the mold (M) and the monomer solution (S) by means of an external input means such as a touch pad or keyboard, and a new type of mold or monomer solution When in use, it is designed to find and set the optimal injection pressure by storing data obtained through repeated tests.

In the present embodiment, the driving unit 22 moves the plunger 23 forward and backward by the power of a motor (not shown) to suck the monomer solution into the syringe 20 or to mold the monomer solution into the mold M. Although configured to inject, the present invention is not limited thereto, and the driving method of the driving unit 22 may use various known methods.

A preferred embodiment of injecting the monomer solution into the mold with the above configuration is as follows.

First, as shown in FIG. 3, the monomer solution (S) is sucked into the syringe 20 to match the cavity capacity of the mold (M) according to the type of mold (M) supplied. At this time, the raw material tank ( The valve V installed between the 10) and the syringe 20 remains open, and the nozzle 21 is blocked from inflow of air from the outside by a built-in check valve (not shown). (20) The upper driving part 22 is operated to fill the syringe 20 with the monomer solution (S) by a fixed amount.

On the other hand, the valve (V) may be controlled by the controller (C) to open and close, and is opened when the drive unit 22 of the syringe 20 performs an inhalation operation using a check valve, and is discharged, that is, Of course, it can also be automatically closed when injection into the mold.

Next, as shown in FIG. 4, when the contour of the mold M is detected in the first area A1 in the image taken by the non-recognition system, the position of the camera is finely adjusted to match the virtual contour L. It is adjusted, and by this, it is recognized that the mold (M) is seated at the injection position, and the driving unit 22 is driven in the opposite direction to the primary, so that the monomer solution (S) inside the syringe 20 is injected into the nozzle ( 21) is injected into the mold (M). At this time, the valve (V) remains closed, and the check valve provided in the nozzle 21 is opened, and the The drive injects only a preset amount of the monomer solution (S), and the preset amount is set to be 70 to 99% of the amount first injected into the syringe 20, more preferably 90 to 98%. has been

In the above step, the injection pressure of the monomer solution (S) is injected at the highest pressure within the range in which bubbles are not generated in the monomer solution according to the viscosity of the monomer solution or the thickness of the cavity inside the mold, so that the injection time can be shortened. do.

Finally, after most of the monomer solution (S) inside the syringe 20 is injected into the mold (M) by the driving of the driving unit 22 as described above, the driving speed of the driving unit 22 is relatively slow to be careful The remaining amount is injected accidentally. At this time, as shown in FIG. 5, whether the oil level of the monomer solution (S) is detected in the second area (A2) located outside the injection port (I) by the vision recognition system It is injected until it is confirmed, and when the oil level of the monomer solution (S) is detected in the second area (A2) located about 1 to 2 mm outside the inlet (I) of the mold (M) by surface tension, the syringe drive unit ( By stopping the operation of 22), the injection of the monomer solution (S) is completed, and after closing the inlet (I) by rewinding the sealing tape (T) that was opened in the subsequent process, the mold is unloaded. The injection of the monomer solution (S) into (M) is completed.

When the outline of the mold (M) in the first area (A1) matches the virtual outline (L) through the above process, the monomer solution (S) is injected at the first injection pressure preset according to the type of supplied mold. Most of the injection is made into the mold (M), and then the remaining amount is injected at a relatively lower pressure than the first injection pressure to check whether the oil level (L1) appears in the second area (A2) located outside the mold (M). is confirmed, and when the oil level L1 appears, the injection of the monomer solution is terminated, and when the oil level does not appear, the monomer solution is injected with fine pressure until the oil level appears in the second area A2.

On the other hand, in the first area and the second area, the contour of the mold or the oil level of the monomer solution is sensed by the change in the number of pixels. As a result, the boundary portion is shown as a linear shadow, and it can be seen that the outline of the mold and the oil surface of the monomer solution are formed by the number of pixels forming the linear shadow photographed in each area.

In this embodiment, since the outline of the mold M and the thickness of the oil level of the monomer solution detected in the regions A1 and A2 are substantially constant, the number of detected pixels is also almost constant, but the peripheral devices are all operating quickly, and people around the equipment and movement of other devices, which may result in erroneous detection due to strange reflections in the mold or monomer solution. Therefore, erroneous detection due to various noises is detected by detecting the amount of change in the number of detected pixels and the direction of movement of shadows. to be able to prevent

In this embodiment, the amount of the monomer solution injected at the first injection pressure is appropriate for 70 to 99% of the total injection amount, but the present invention is not limited thereto, and the first injection amount varies somewhat depending on the type of mold and the viscosity of the monomer solution. Of course, it can also be set. The amount of the monomer solution injected at the first injection pressure is more preferably 90 to 98% of the total injection amount.

According to the above-described automatic monomer solution injection method according to an embodiment of the present invention, most of the monomer solution is initially injected into the mold at a high speed, that is, at high pressure, within the shortest time, and then the oil level of the monomer solution is detected in the second area. By injecting the remaining amount at a relatively slow speed until the cavity inside the mold is filled, the time required for injection of the monomer solution can be shortened and the exact amount can be injected without overflowing, resulting in improved productivity and uniformity due to shortened process time. There is an advantage of being able to manufacture a lens of one quality, and there is also an advantage of not causing defects and malfunctions of the manufacturing apparatus due to insufficient or excessive monomer injection amount.

According to a preferred embodiment of the present invention as described above, after rapidly injecting most of the monomer solution having a viscosity into the cavity inside the mold at a first high pressure, in the final step, while using a vision recognition system, the injection pressure is lowered to gradually inject the remaining amount to fill the Therefore, there is no fear of exceeding the injection capacity. In addition, after injecting most of the monomer solution into the mold within a short time, the injection is stopped when the monomer solution in the second area is detected by the vision recognition system, so there is no remaining air bubble and the injected amount of the monomer solution is accurately quantified. Since this is injected, lenses of uniform quality can be produced, and the monomer injection time can be shortened, thereby maximizing the efficiency of the monomer injection operation. Accordingly, it is possible to prevent defects due to an insufficient injection amount of the monomer solution and to prevent abnormal operation or breakdown of equipment caused by excessive injection of the monomer solution.

C: Controller
I: inlet
L: virtual contour
L1: oil level
M: mold
A1,A2: detection area
S: monomer solution
T : sealing tape
V: valve
10: raw material tank
20: Syringe
21: Nozzle
22: driving unit
23: plunger

Claims (12)

As a method of injecting a monomer composition for a thiourethane-based optical material into a cavity formed between a pair of molds sealed on the outside,
(a) preparing a monomer composition for a thiourethane-based optical material having a solid refractive index of 1.523 to 1.690 and a viscosity of 20 to 1,000cps (25° C.);
(b) injecting a majority of the monomer composition into the cavity;
(c) injecting the monomer composition into the cavity following the step (b), detecting the oil level using a vision recognition system, and terminating the injection of the monomer composition when the oil level is detected at the set final injection point; including,
The vision recognition system photographs the contour of the mold and the oil level of the monomer solution injected into the mold, and detects the state in which the mold is set at the injection position. A method of automatically injecting a mold for a monomer for a thiourethane-based optical material, characterized in that by setting a second area located there.
delete The method of claim 1,
The vision recognition system injects most of the monomer solution into the mold at a set first injection pressure when the controller detects the contour of the mold in the first region, and then the remaining amount of the monomer solution at a pressure lower than the first injection pressure. Characterized in that, when the oil level is detected in the second area while injecting, the injection of the monomer solution is terminated.
According to claim 1 or 3,
In the first and second regions, the contour of the mold and the oil level of the monomer solution are detected by a change in the number of pixels, a method for automatically injecting a monomer for a thiourethane-based optical material into a mold.
According to claim 1 or 3,
A virtual contour is displayed in the form of an arc in the first area, and when the mold contour is detected in the first area, the photographing position is adjusted so that the contour of the captured mold matches the virtual contour, and the position change of the first area A method for automatically injecting a monomer for a thiourethane-based optical material into a mold, characterized in that the position of the second region is moved together to detect a change in oil level according to.
According to claim 1 or 3,
The first region is characterized in that set at a position having both the X-direction information and the Y-direction information of the mold among the outer edges of the mold, a method of automatically injecting a monomer for a thiourethane-based optical material into a mold.
The method of claim 3,
In the step of injecting the monomer composition into the mold at the first injection pressure, 70 to 99% of the volume of the cavity inside the mold is injected.
According to claim 1 or 3,
The monomer composition for thiourethane-based optical materials comprises a polythiol compound and a polyisocyanate compound.
The method of claim 8,
The polyisocyanate compound is isophorone diisocyanate, dicyclohexylmethane-4,4-diisocyanate (H ₁₂ MDI), hexamethylene diisocyanate, methylcyclohexane diisocyanate, tolylene diisocyanate, phenylene diisocyanate, 1,3, 5-tris(6-isocyanato-hexyl)-[1,3,5]-trizianane-2,4,6-trione (HDI trimer), o,m,p-xylylenediisocyanate (o , m, p-xylylene diisocyanate) and tetramethylxylylene diisocyanate (TMXDI), characterized in that one or more compounds selected from the group consisting of, mold automatic injection method of thiourethane-based optical material monomer .
The method of claim 8,
The polythiol compound is 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane, 2,3-bis (2-mercaptoethylthio) -3-propane-1-thiol, 2,2-bis(mercaptomethyl)-1,3-propanedithiol, bis(2-mercaptoethyl)sulfide, tetrakis(mercaptomethyl)methane; 2-(2-mercaptoethylthio)propane-1,3-dithiol, 2-(2,3-bis(2-mercaptoethylthio)propylthio)ethanethiol, bis(2,3-dimercapto Propanyl) sulfide, bis(2,3-dimercaptopropanyl)disulfide, 1,2-bis(2-mercaptoethylthio)-3-mercaptopropane, 1,2-bis(2-(2- Mercaptoethylthio)-3-mercaptopropylthio)ethane, bis(2-(2-mercaptoethylthio)-3-mercaptopropyl)sulfide, 2-(2-mercaptoethylthio)-3-2 -Mercapto-3-[3-mercapto-2-(2-mercaptoethylthio)-propylthio]propylthio-propane-1-thiol, 2,2-bis-(3-mercapto-propionyloxy) Methyl)-butyl ester, 2-(2-mercaptoethylthio)-3-(2-(2-[3-mercapto-2-(2-mercaptoethylthio)-propylthio]ethylthio)ethylthio ) Propane-1-thiol, (4R,11S)-4,11-bis(mercaptomethyl)-3,6,9,12-tetrathiatetradecane-1,14-dithiol, (S)-3- ((R-2,3-dimercaptopropyl)thio)propane-1,2-dithiol, (4R,14R)-4,14-bis(mercaptomethyl)-3,6,9,12,15 -pentathiaheptane-1,17-dithiol, (S)-3-((R-3-mercapto-2-((2-mercaptoethyl)thio)propyl)thio)propyl)thio)-2- ((2-mercaptoethyl)thio)propane-1-thiol, 3,3'-dithiobis(propane-1,2-dithiol), (7R,11S)-7,11-bis(mercaptomethyl) -3,6,9,12,15-pentatierheptane-1,17-dithiol, (7R,12S)-7,12-bis(mercaptomethyl)-3,6,9,10,13,16 -Hexathiaoctadecane-1,18-dithiol, 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4,7-dimercaptomethyl- 1,11-dimercapto-3,6,9-trithiaundecane, 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, pentaerythritol Tetrakis(3-mercaptopropionate), trimethylolpropane tris(3-mercaptopropionate), pentaerythritoltetrakis(2-mercaptoacetate), bispentaerythritol-ether-hexakis (3-mercaptopropionate), 1,1,3,3-tetrakis(mercaptomethylthio)propane, 1,1,2,2-tetrakis(mercaptomethylthio)ethane, 4,6- One or two or more selected from the group consisting of bis(mercaptomethylthio)-1,3-dithiane and 2-(2,2-bis(mercaptodimethylthio)ethyl)-1,3-dithiane Characterized in that it is a compound, a mold automatic injection method of a monomer for a thiourethane-based optical material.
The method of claim 8,
The monomer composition for a thiourethane-based optical material further comprises an internal release agent, a method for automatically injecting a mold of a monomer for a thiourethane-based optical material.
The method of claim 8,
Characterized in that the injection of the monomer composition is made in the temperature range of 5 ~ 60 ℃, the mold automatic injection method of the monomer for thiourethane-based optical material.

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