WO2019221403A1 - Method for automatically injecting, into mold, acrylic monomer for optical material - Google Patents

Abstract

The present invention relates to a method for preparing an optical material by injecting an acrylic monomer solution into a cavity formed between a pair of externally sealed molds and, more specifically, to a method for automatically injecting, into a mold, an acrylic monomer for an optical material, the method enabling quantitative injection within a short time by means of a vision recognition system while injecting the acrylic monomer solution into the cavity. The present invention provides a method for automatically injecting, into a mold, an acrylic monomer for an optical material, comprising the steps of: (a) preparing an acrylic monomer composition for an optical material, having a solid phase refractive index of 1.50-1.63 and a viscosity of 20-1,000 cps (25°C); (b) injecting most of the monomer composition into a cavity formed between a pair of externally sealed molds; and (c) detecting the surface of oil by means of a vision recognition system while injecting the monomer composition into the cavity continuously from step (b), so as to terminate the injection of the monomer composition when the surface of the oil is detected at a set final injection point. According to the present invention, the acrylic monomer solution for an optical material can be automatically and quantitatively injected in a proper amount into a mold.

Description

Mold injection method of monomer for acrylic optical material

The present invention relates to a method of manufacturing an optical material by injecting an acrylic monomer solution into a cavity formed between a pair of molds with an outer seal, and more particularly, using a vision recognition system while injecting an acrylic monomer solution into the cavity. The present invention relates to a method of automatically injecting a mold for an acrylic optical material monomer to enable a quantitative injection within a short time.

In optical materials, plastic lenses are lighter than glass lenses, do not break easily, and have good workability. Therefore, plastic lenses are used more recently than glass lenses. Such a plastic lens is manufactured by injecting a polymer compound called a monomer into a mold and hardening it, followed by appropriate post-processing. That is, the monomer solution is manufactured by injecting a monomer solution into a mold having a lens-shaped empty injection space (cavity).

As a related art, Patent Document 1 discloses a 'moving distance setting device of a mold for manufacturing an eyeglass lens'.

Patent Document 1 is a state in which the glass molds are spaced apart from each other using a mold chuck in order to accurately determine the separation distance of the glass mold for manufacturing the spectacle lens, the adhesive is taped to the outer peripheral surface of the glass mold and the monomer on the glass mold is completed The method of injecting the solution manually is introduced.

By the way, since the technique of manually injecting the monomer into the glass mold as disclosed in Patent Document 1 depends entirely on the degree of skill of the injector, defects may occur depending on the level of skill and the work efficiency is inferior. In particular, precisely injecting a monomer in a predetermined amount every time requires a lot of skill, there is a problem that bubbles may occur in the mold in the case of unskilled people.

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

The acrylate-based optical material can be made into a structure having a high transmittance of the spectacle lens and less chemical influence on other compounds in the molecule, and thus is widely used for lenses or photochromic lenses requiring high transparency. The composition for epoxy acrylic optical materials disclosed in Korean Patent Nos. 10-0496911, 10-0498896, etc., has a high refractive index and high Abbe's number, excellent optical properties such as transparency, light weight, and heat resistance, and low cost of materials. Has the advantage. Reducing production costs is one of the major concerns in the field of optical lenses, including acrylate-based optical materials. If automatic injection is possible in an automatic production facility without going through a human hand, not only productivity improvement but also human hazards in the production process can be solved. However, despite many attempts, automation of injection is still difficult. This is also caused by the high viscosity of the monomer, the difference in viscosity and pot life according to the composition.

Patent Document 2 (Korean Patent No. 10-1383132) discloses a monomer auto-injection equipment for eyeglass lenses and a method for producing eyeglass lenses using the same. In patent document 2, the position of a lens mold is grasped | ascertained by using the displacement sensor (laser sensor) which detects the position of a lens mold in the step of injecting a monomer solution into the cavity formed by a pair of mold, and the 2nd movement It is to detect the water level of the raw material to be filled in the lens mold by the unit, and the injection amount of the monomer of the injection nozzle is to be controlled by the injection amount adjusting unit, but when the monomer reaches a certain level, the amount of monomer injected is 5mm and 1 step It is adjusted to 10mm which is 2 steps.

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 the water level is not a horizontal change but a two-dimensional symmetrical parabola. As a result, it was difficult to accurately detect the water level in real time, which made it difficult to inject the correct amount despite the stepwise adjustment of the injection amount, resulting in insufficient injection amount or excessive injection amount, leading to product defects or overflowing monomers. The composition could contaminate the injection equipment.

In addition, `` Plastic product manufacturing method and manufacturing apparatus '' of Patent Document 3 (Japanese Patent No. 3707189) is a method for automating the process of injecting a plastic stock solution into a molding mold during a plastic lens manufacturing process. The first flow rate and the first time are set by measuring the width between the first and second wall portions, and the first step of injecting the plastic stock solution for the first time at the first flow rate into the cavity; and the first step following the first step. It has a second process of injecting the plastic stock solution at a second flow rate less than the flow rate so as to inject the stock solution at a large flow rate only for a predetermined time, and then, after the injection of the stock solution at a small flow rate toward the end of the injection, At the same time, the amount of leakage can be reduced.

However, in the injection method according to Patent Document 3, it is possible to shorten the injection time and reduce the leakage amount by gradually reducing the injection amount and injection time of the plastic raw material in consideration of the spatial characteristics inside the cavity, but the monomer is injected into the mold By not considering the oil level change characteristics of the highly viscous monomer solution, there are still disadvantages in that the leakage is poor and the metering is difficult.

In `` Plastic Lens Molding Method '' of Patent Document 4 (Japanese Patent Laid-Open No. 2007-80766), bubbles are not left as much as possible when injecting the liquid molding material into the mold in the same manner as pouring a glass by tilting a glass. Initially, the inlet is deviated to one side from the upper center in the middle so that it can be filled without filling, and when the injection is proceeded to some extent, the mold is rotated (tilt) so that the inlet is located in the upper center of gravity to fill the raw monomer. A molding method of 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 it was still difficult to inject the raw material in the correct amount.

[Preceding technical literature]

[Patent Documents]

(Patent Document 1) 1. Republic of Korea Utility Model Registration No. 20-0236704

(Patent Document 2) 2. Republic of Korea Patent No. 10-1383132

(Patent Document 3) 3. Japanese Patent No. 3707189

(Patent Document 4) 4. Japanese Patent Application Publication No. 2007-80766

(Patent Document 5) 5. Republic of Korea Patent No. 10-0496911

(Patent Document 6) 6. Republic of Korea Patent No. 10-0498896

As described above, many prior arts propose a method for automatically injecting a monomer for an optical material into a mold, but all have difficulty in injecting the monomer in an accurate amount without overflowing or shortening the monomer. In addition, each monomer has a difference in curing rate, curing time, difference in viscosity, difference in oil level, and composition in the same series of monomers. There is a problem that it is difficult to precise injection because it can not cope with the difference.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a method of automatically injecting a mold for an acrylic optical material monomer capable of accurately injecting a monomer composition for an acrylic optical material into a mold without a lack of injection amount or excessive injection amount. To provide.

In particular, the present invention, while injecting the monomer composition for acrylic optical material divided into the cavity of the mold in two stages, most of them are injected in the first stage, and then in the second stage to detect the oil level of the acrylic monomer solution using a vision recognition system It is an object of the present invention to provide a method of automatically injecting a monomer for an acrylic optical material that can shorten the injection time by stopping the injection when the final injection point is detected and can quantify the monomer solution so that it does not overflow or run short. .

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

A method of injecting a monomer composition for an acrylic optical material into a cavity formed between a pair of molds having an outer seal,

(a) preparing a monomer composition for acrylic optical materials having a solid phase refractive index of 1.50 to 1.63 and a viscosity of 20 to 1,000 cps (25 ° C.);

(b) injecting most of said monomer composition into said cavity;

(c) following the step (b) following the step of injecting the monomer composition into the cavity while detecting the oil surface using a vision recognition system to terminate the injection of the monomer composition when the oil surface is detected at the final injection point set; Provided is a method of automatically injecting a mold for an optical material monomer.

In step (b), the monomer composition may be injected into the cavity by a predetermined weight or volume, or may be injected to a predetermined area in 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, wherein the first region is located at a part of the mold contour to detect a state in which the mold is set at the injection position, and outside the mold. The second area located may be set.

In the vision recognition system in which the first and second regions are set as described above, the controller injects most of the monomer solution into the mold at the first injection pressure, when the controller detects the contour of the mold in the first region. If the oil level is detected in the second region 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 contour of the mold and the oil level of the monomer solution are detected by the change in the number of pixels.

In a preferred embodiment of the present invention, the virtual contour is displayed in the form of an arc in the first region, the photographing position is adjusted so that the contour of the mold photographed when the mold contour in the first region is matched with the virtual contour. As the position of the first region changes, the position of the second region is moved together to detect a change in oil level.

In a preferred embodiment, the first region means a position having both diagonal direction information, that is, the X direction information and the Y direction information of the mold, and the position change of the mold when the mold is placed as an injection position. The first region serves as a reference for the positional movement of the second region. In the first region, the contour of the mold is immediately detected when the mold is seated at the injection position.

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

In a preferred embodiment, the controller is to inject 70 ~ 99% of the monomer solution at a high pressure, that is, at a high speed when the first injection of the monomer solution injected into the syringe into the mold, and to slowly inject the remaining amount at a low pressure Control the syringe drive.

The monomer composition for an acrylic optical material preferably includes any one or more of an epoxy acrylate compound represented by Formula 1 below and an epoxy acrylate compound represented by Formula 2 below.

[Formula 1]

(Where n = 0-15, R ₁ is H or CH ₃ and R ₂ is H or Br)

[Formula 2]

(Where R1 and R2 are H or CH ₃ , m = 0-5, n = 0-5, m and n are not 0 at the same time, and m + n = 1-10).

Injection of the monomer composition is preferably made in a temperature range of 5 ~ 60 ℃.

According to the present invention, when the injection of the monomer for acrylic optical material 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 amount of the monomer solution is not short and not overflowed. Do.

In addition, it is possible to quantitatively irrespective of the difference in viscosity and the shape of the oil surface, because the oil is injected while checking the oil level by using a vision recognition system instead of simply adjusting the amount or speed of mechanical injection.

In addition, since the injection time of the monomers can be shortened by providing a step of injecting most of the monomers into the cavity inside the mold firstly quickly, it is easy to set the injection to be completed within a predetermined pot life, and thus curing according to the monomers. Irrespective of the difference in speed and curing time, dosing can be carried out at optimum conditions before curing.

According to the present invention, it is possible to produce high quality acrylic lenses by automatic injection without defects due to lack of injection amount or excess, so that the productivity can be greatly improved and the production cost can be reduced by reducing the labor cost, and the operator can directly Abnormal operation or failure of the equipment due to exposure problems and excessive injection of the monomer composition can also be prevented.

1 is a flowchart schematically illustrating a lens manufacturing process according to an embodiment of the present invention;

2 is a block diagram of a monomer automatic injection method according to an embodiment of the present invention,

3 is a state in which the monomer solution is first suctioned into the syringe in FIG. 2,

4 is a state in which the monomer solution is injected into the mold in FIG.

FIG. 5 illustrates a state in which the monomer solution is filled in the mold in FIG. 4.

Hereinafter, a method of automatically injecting a mold for an acrylic optical material monomer of the present invention will be described step by step by preferred embodiment.

The automatic mold injection method of the monomer for acrylic optical material of the present invention,

(a) preparing a monomer composition for acrylic optical materials having a solid phase refractive index of 1.50 to 1.63 and a viscosity of 20 to 1,000 cps (25 ° C.);

(b) injecting most of said monomer composition into a cavity formed between a pair of molds with outer seals;

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

The monomer composition for acrylic optical materials is meant to include all of compositions having a acrylate monomer as a main component. In the present invention, the 'monomer solution' refers to when the monomer composition is in a liquid state with fluidity.

The monomer composition for acrylic optical materials has a viscosity of 20 to 1,000 cps at a solid phase refractive index of 1.50 to 1.63 and 25 ° C. More preferably, the viscosity is 30-500 cps at 25 degreeC.

The monomer composition for an acrylic optical material preferably includes any one or more of an epoxy acrylate compound represented by Formula 1 below and an epoxy acrylate compound represented by Formula 2 below.

[Formula 1]

(Where n = 0-15, R ₁ is H or CH ₃ and R ₂ is H or Br)

[Formula 2]

(Where R1 and R2 are H or CH ₃ , m = 0-5, n = 0-5, m and n are not 0 at the same time, and m + n = 1-10).

The monomer composition for acrylic optical materials may include styrene, divinylbenzene, alphamethylstyrene, alphamethylstyrene dimer, methyl methacrylate, benzyl methacrylate, chlorostyrene, bromostyrene, methoxy styrene, monobenzyl maleate, Dibenzyl maleate, monobenzyl fumarate, dibenzyl fumarate, methylbenzyl maleate, dimethyl maleate, diethyl maleate, dibutyl maleate, dibutyl fumarate, monobutyl maleate, monopentyl maleate, diphene It may further comprise one or two or more compounds selected from the group consisting of tilmaleate, monopentyl fumarate, dipentyl fumarate and diethylene glycol bisaryl carbonate.

In addition, the monomer composition for acrylic optical material may further include an internal mold release agent. By adding an internal mold release agent in a monomer composition before casting polymerization, mold release property after superposition | polymerization can be improved significantly. The internal mold release agent may preferably be included in the composition in an amount of 0.001 to 10% by weight.

As an internal mold release agent, a phosphate ester compound, a silicone type surfactant, a fluorine type surfactant, an alkyl quaternary ammonium salt, etc. can be used individually or in combination of 2 or more types, respectively.

Fluorine-based nonionic surfactants are compounds having a perfluoroalkyl group in the molecule, such as Eudin DS-401 ™ (Japan, Daishin Industrial Co., Ltd.), Unidin DS-403 ™ (Japan, Daikin Industrial Co., Ltd.), Eftop EF. 122A ™ (Japan, Shin-Avada Chemical Co., Ltd.), Effope EF 126 ™ (Japan, Shin-Avada Chemical Co., Ltd.), and Eftop EF 301 ™ (Japan, Shin-Avada Chemical Co., Ltd.).

Silicone-based nonionic surfactants are compounds having a dimethylpolysiloxane group in a molecule, such as Q2-120A ™ of Dow, USA.

Alkyl quaternary ammonium salts are commonly known as cationic surfactants, and there are halogem salts, phosphates, sulfates and the like, and examples of the chloride type thereof include trimethylcetyl ammonium chloride, trimethyl stearyl ammonium chloride, dimethylethylcetyl ammonium chloride, Triethyldecylammonium chloride, trioctylmethyl ammonium chloride, diethylcyclohexide, decylammonium chloride and the like.

 Preferably, a phosphate ester compound can be used as an internal mold release agent. The phosphate ester compound is a compound having a phosphate ester group, and is, for example, isopropyl acid phosphate, diisopropyl acid phosphate, butylic acid phosphate, dibutyl phosphate, octylic acid phosphate, dioctyl acid phosphate, isodecyl acid phosphate, or diisode. Carboxylic acid phosphate, tridecanoic acid phosphate, bis (tridecanoic acid) phosphate, and mixtures of two or more thereof. As the phosphate ester compound, preferably polyoxyethylene nonylphenol ether phosphate (5% by weight of 5 mole of ethylene oxide added, 80% by weight of 4 mole added, 10% by weight of 3 mole added, 1 mole added) 5% by weight), polyoxyethylene nonylphenyl phosphate (5% by weight of 9 mol of ethylene oxide added, 80% by weight of 8 mol of ethylene oxide, 10% by weight of 7 mol of ethylene oxide, ethylene 5% by weight of oxide added up to 6 mol), polyoxyethylenenonylphenol ether phosphate (3% by weight of 11 moles of ethylene oxide added, 80% by weight of 10 moles added, 5% by weight of 9 moles added, 7 mole added 6% by weight, 6 mole added 6% by weight), polyoxyethylene nonylphenol ether phosphate (13 mole added by ethylene oxide 3% by weight, 12 mole added by 80% by weight, 11 mole added 8% by weight, 9% by weight added 3% by weight, 4% by weight added 6% by weight), polyoxy Ethylene nonylphenol ether phosphate (3% by weight of 17 moles of ethylene oxide added, 79% by weight of 16 moles added, 10% by weight of 15 moles added, 4% by weight, 14 moles added, 13 moles added 4 wt%), polyoxyethylenenonylphenol ether phosphate (21 wt% added ethylene oxide 5 wt%, 20 mol added 78 wt%, 19 mol added 7 wt%, 18 mol added 6 wt% %, 17 mole added 4% by weight), dioctyl acid phosphate and Zelec UN ™ can be used one or two or more compounds selected from the group consisting of.

The monomer composition of the present invention may further include a heat stabilizer. The heat stabilizer may be included in the composition of the present invention preferably 0.01 to 5.00% by weight. When the thermal stabilizer is used at less than 0.01% by weight, the thermal stability effect is weak. When the thermal stabilizer is used at more than 5.00%, the polymerization failure rate during curing may be high and the thermal stability of the cured product may be lowered.

Examples of the heat stabilizer include calcium stearate, barium stearate, zinc stearate, cadmium stearate, lead stearate, magnesium stearate, aluminum stearate, potassium stearate and zinc octoate, which are metal fatty acid salts. One or two or more compounds selected from the compounds can be used.

Preferably, triphenyl phosphite, diphenyldecyl phosphite, phenyl diddecyl phosphite, diphenyl dodecyl phosphite, diphenyl isodecyl phosphate, trinolyl phenyl phosphite, diphenyl isooctyl phosphite, and triphosphate One or two or more compounds selected from butyl phosphite, tripropyl phosphite, triethyl phosphite, trimethyl phosphite, tris (monodecyl phosphite) and tris (monophenyl) phosphite can be used. Especially preferably, diphenylisodecyl phosphate can be used.

In addition, one or two selected from compounds such as lead-based 3PbO.PbSO ₄ .4H ₂ O, 2PbO.Pb (C ₈ H ₄ O ₄ ), 3PbO.Pb (C ₄ H ₂ O ₄ ) .H ₂ O The above can also be used.

In addition, dibutyltin diaurate, dibutyltin maleate, dibutyltin bis (isooctyl maleate), dioctyl maleate, dibutyltin bis (monomethyl maleate), and dibutyltin bis Uryl mercaptide), dibutyl bis (isooxyl mercaptoacetate), monobutyl tin tris (isooctyl mercaptoacetate), dimethyl tin bis (isooctyl mercaptoacetate), tris (isooctyl mercaptoacetate), fertility Tiltin bis (isooctyl mercaptoacetate), dibutyl tin bis (2-mercapto ethyl laurate), monobutyl tin tris (2- mercapto ethyl laurate), dimethyl tin bis (2- mercapto ethylate) And 1 type, or 2 or more types selected from compounds, such as a monomethyltin tris (2-mercapto ethyl laurate), can also be used.

Moreover, it is also possible to mix and use 2 or more types of heat stabilizers from which the series differs among the heat stabilizers illustrated above. Most preferably, by using a phosphorus-based heat stabilizer, the thermal stability of the optical lens can be greatly improved without deteriorating not only the initial color of the molded lens but also optical properties such as transparency, impact strength, heat resistance and polymerization yield.

The monomer composition of the present invention further includes a polymerization catalyst, an ultraviolet absorber, an organic dye, an inorganic pigment, an anti-coloring agent, an antioxidant, a light stabilizer, etc. according to a conventional technique in the field of plastic optical lenses, as needed. can do.

The injection into the mold of the monomer composition is preferably made in a temperature range of 5 to 60 ° C, more preferably in a temperature range of 5 to 40 ° C. It is possible to maintain the pot life properly by injecting at an appropriate temperature, and to improve the quality of the optical material by lowering the incidence of striae, rings, and variable uncured resins in the finally obtained optical material.

In step (b), the monomer composition may be injected into the cavity by a predetermined weight or volume, or may be injected to a predetermined area in the mold using a vision recognition system. The step (c) is to detect the oil surface using a vision recognition system to terminate the injection of the monomer composition when the oil surface is detected at the final injection point set.

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 includes loading a mold (S10), taping (S20), opening a tape (S30), and injecting a monomer ( S40), the tape closing (S50) and the mold unloading (S60) step, and the subsequent process of curing the monomer after the separation from the mold to complete the lens, these processes are basically the same as the existing method Do.

In the present embodiment, the monomer of the raw material tank is injected into the cavity of the mold, and a specific method of stopping the injection of the monomer solution is provided by detecting the oil level using a vision recognition system and detecting the oil level at the final injection point. As shown in 2 to 5, the monomer solution (S) of the monomer solution tank (10) is first suctioned into the syringe (20) capable of volume control according to the cavity of the mold (M), and then the syringe (20) Inject the monomer solution (S) injected into the mold (M) in the second most of the amount at a high speed, and lower the injection pressure to inject the remaining amount, finally using the non-recognition system to the monomer solution (S) The injection is finished after confirming that the mold M is filled inside.

In the present exemplary embodiment, the vision recognition system photographs the contour of the mold M and the oil level L1 of the monomer solution S injected into the cavity of the mold M, as shown in FIGS. 2 to 5. The first region A1 of a part of the contour of the mold M and the second region A2 located outside the injection hole of the mold M are set to detect a state in which the mold M is set at the injection position. It is.

On the other hand, the controller (C) is the image signal photographed by the vision recognition system, that is, as shown in Figure 2 when the contour of the mold (M) is detected in the first area (A1), the mold (M) in the injection position In this case, the contour of the mold M and the virtual contour L displayed in the arc shape in the first area A1 are determined to match. Fine adjustment, that is, by adjusting the position of the vision camera is subjected to a photographing position adjusting step of matching the virtual contour (L) with the contour of the mold (M).

In the photographing position adjusting step, the position of the first region A1 is adjusted and at the same time the position of the second region is equidistantly moved together with the first region A1, so that the position of the mold M is placed in the injection apparatus. Although slightly changed by the second area (A2) to be photographed in the vision recognition system to capture the same position to detect the change in the surface of the monomer solution.

In addition, the controller (C) analyzes the image taken by the vision recognition system to detect the capacity of the cavity and whether the injection position is set according to the type of the mold (M), and the drive unit 22 and the valve of the syringe 20 ( By controlling the opening and closing operation of V), as shown in FIG. 3, the amount of first suction of the monomer solution S into the syringe 20 and the time of injection of the monomer solution M into the mold M, the injection pressure, and the end point of injection are shown. Control and fine adjustment 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 an external input means such as a touch pad or a keyboard, and a new type of mold or monomer solution. In use, it is possible to find and set the optimum injection pressure by storing the data obtained through repeated tests.

In the present embodiment, the driving unit 22 inhales the monomer solution into the interior of the syringe 20 by the plunger 23 is moved forward and backward by the power of a motor (not shown), or the sucked 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.

Referring to the preferred embodiment of injecting the monomer solution into the mold in the above configuration as follows.

First, as shown in FIG. 3, the monomer solution S is sucked into the syringe 20 so as to match the cavity capacity of the mold M according to the type of the mold M supplied, wherein the raw material tank ( The valve (V) installed between the 10) and the syringe 20 maintains an open state, and the nozzle 21 portion of the nozzle 21 has a syringe in a state in which air from the outside is blocked by a built-in check valve (not shown). (20) The upper driving unit 22 is operated to fill the monomer 20 with the quantitative amount of the monomer solution S.

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

Next, when the contour of the mold M is detected in the first area A1 in the image captured by the non-electrical system, as shown in FIG. 4, the position of the camera is finely adjusted to match the virtual contour L. It is understood 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 nozzled. It is injected into the mold (M) through the 21, wherein the valve (V) is maintained in a closed state, the check valve provided in the nozzle 21 in the open state of the drive unit 22 The driving is to inject only a predetermined amount of the monomer solution (S), the predetermined amount is set to be 70 to 99% of the amount first injected into the syringe 20, more preferably 90 to 98% It is.

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

Finally, after the majority of the monomer solution S in 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 slowed to be careful. In this case, 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 hole I by the vision recognition system as shown in FIG. 5. Until it is confirmed, and when the surface of the monomer solution (S) is detected in the second area (A2) located about 1 to 2 mm outside of the injection hole (I) of the mold (M) by the surface tension, the syringe driver ( The injection of the monomer solution S is completed by stopping the operation of 22). The sealing tape T, which was opened in the subsequent process, is wound again to close the injection port I, and then the mold is unloaded. Injection of monomer solution (S) to (M) is completed The.

When the contour of the mold M in the first region A1 is matched to the virtual contour L through the above process, the monomer solution S is applied at a first injection pressure set in advance according to the type of the supplied mold. Most of the injection into the mold (M), and then the remaining amount is injected at a pressure relatively lower than the first injection pressure and whether the oil surface (L1) appears in the second area (A2) located outside the mold (M) When the oil surface (L1) appears to confirm whether the injection of the monomer solution is terminated, if the oil surface does not appear, the monomer solution is injected at a minute pressure until the oil surface appears in the second region (A2).

Meanwhile, in the first region and the second region, the contour of the mold or the oil level of the monomer solution is detected by the change in the number of pixels. The contour of the mold and the oil level of the monomer solution are determined by the difference in density between air, the mold, and the monomer solution. As a result, the boundary portion is seen as a linear shade, whereby the outline of the mold and the oil surface of the monomer solution are formed by the number of pixels formed by the linear shade photographed in each region.

In this embodiment, the contour of the mold M detected in the areas A1 and A2 and the surface thickness of the monomer solution are generally constant, so that the number of pixels detected is almost constant, but the peripheral parts are all operating rapidly, And other movements of the device, which may be reflected by a strange phenomenon in the mold or the monomer solution, and thus may be misdetected. To prevent this.

In the present embodiment, the amount of the monomer solution injected at the first injection pressure is appropriately 70 to 99% of the total injection amount, but the present invention is not limited thereto, and the primary injection amount is somewhat different depending on the type of mold and the viscosity of the monomer solution. Of course, it can 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 method of automatically injecting the monomer solution according to the embodiment of the present invention described above, most of the monomer solution is initially injected into the mold at a high speed, that is, at a high pressure, within the shortest time, and then the oil level of the monomer solution is detected in the second region. By injecting the remaining amount until the cavity inside the mold is filled at a relatively slow speed until shortening, it is possible to shorten the time required for the injection of the monomer solution while injecting the correct amount without overflow. There is an advantage in that it is possible to manufacture a lens of a quality, there is also an advantage such that the failure caused by the lack or excessive amount of monomer injection, and also does not cause malfunction of the manufacturing apparatus.

According to a preferred embodiment of the present invention as described above, the most viscous monomer solution is rapidly injected into the cavity inside the mold at a high first pressure, and then the remaining pressure is gradually filled to reduce the injection pressure while using a vision recognition system at the final stage. As such, there is no risk of exceeding the injection volume. In addition, most of the monomer solution is injected into the mold within a short time, and when the monomer solution in the second area is detected by the vision recognition system, the injection is terminated. Since the injection can produce a lens of uniform quality, and can shorten the injection time of the monomer can maximize the efficiency of the monomer injection operation. Accordingly, it is possible to prevent defects due to insufficient injection amount of the monomer solution and to prevent abnormal operation or failure of equipment caused by excessive injection of the monomer solution.

[Description of the code]

C: Controller

I: inlet

L: virtual contour

L1: oil cotton

M: Mold

A1, A2: detection area

S: monomer solution

T: sealing tape

V: Valve

10: raw material tank

20: syringe

21: nozzle

22: drive unit

23: plunger

Claims (10)

1. A method of injecting a monomer composition for an acrylic optical material into a cavity formed between a pair of molds having an outer seal,

   (a) preparing a monomer composition for an acrylic optical material having a solid refractive index of 1.50 to 1.63 and a viscosity of 20 to 1,000 cps (25 ° C.);

   (b) injecting most of said monomer composition into said cavity;

   (c) following the step (b) following the step of injecting the monomer composition into the cavity and detecting the oil surface using a vision recognition system to terminate the injection of the monomer composition if the oil surface is detected at the final injection point set; Mold injection method of monomer for optical materials.
2. The method according to claim 1,

   The vision recognition system photographs the contour of the mold and the oil level of the monomer solution injected into the mold, wherein the first region is located at a part of the mold contour to detect a state in which the mold is set at the injection position, and outside the mold. A method for automatically injecting a mold for monomers for acrylic optical materials, characterized in that the second area is located.
3. The method according to claim 2,

   The vision recognition system, when the controller detects the contour of the mold in the first region, injects most of the monomer solution into the mold at the first injection pressure. Then, the remaining amount of the monomer solution is lower than the first injection pressure. The injection of the monomer solution, characterized in that the injection of the monomer solution is terminated when the oil level is detected in the second region while injecting, the mold automatic injection method of the monomer for acrylic optical material.
4. The method according to claim 2 or 3,

   In the first and second areas, the contour of the mold and the oil level of the monomer solution are detected by changing the number of pixels.
5. The method according to claim 2 or 3,

   The virtual contour is displayed on the first region in the form of an arc, and the photographing position is adjusted so that the contour of the mold photographed when the mold contour is detected in the first region matches the virtual contour, and the position change of the first region is performed. According to claim 1, wherein the position of the second region is moved together to detect the change in the surface, the automatic injection method of the mold for the acrylic optical material monomer.
6. The method according to claim 2 or 3,

   And the first region is 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.
7. The method according to claim 3,

   In the step of injecting the monomer composition into the mold at a first injection pressure, 70 to 99% of the cavity volume inside the mold, characterized in that the injection molding method of the monomer for acrylic optical material.
8. The method according to any one of claims 1 to 3,

   The monomer composition for an acrylic optical material may include any one or more of an epoxy acrylate compound represented by Chemical Formula 1 below and an epoxy acrylate compound represented by Chemical Formula 2 below. Way.

   [Formula 1]

   

   (Where n = 0-15, R ₁ is H or CH ₃ and R ₂ is H or Br)

   [Formula 2]

   

   (Where R1 and R2 are H or CH ₃ , m = 0-5, n = 0-5, m and n are not 0 at the same time, and m + n = 1-10).
9. The method according to claim 8,

   The monomer composition for the acrylic optical material

   Styrene, divinylbenzene, alphamethylstyrene, alphamethylstyrene dimer, methyl methacrylate, benzyl methacrylate, chlorostyrene, bromostyrene, methoxy styrene, monobenzyl maleate, dibenzyl maleate, monobenzyl fumalate , Dibenzyl fumarate, methylbenzyl maleate, dimethyl maleate, diethyl maleate, dibutyl maleate, dibutyl fumarate, monobutyl maleate, monopentyl maleate, dipentyl maleate, monopentyl fumarate, diphene A method for automatically injecting a mold for an acrylic optical material, characterized by further comprising one or two or more compounds selected from the group consisting of tilfumalate and diethylene glycol bisaryl carbonate.
10. The method according to claim 8,

    Injection of the monomer composition is a mold automatic injection method of the monomer for acrylic optical material, characterized in that the temperature range of 5 ~ 60 ℃.

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