JP3820015B2 - Molds for optical lenses and molded products for eyeglass lenses - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is applied when an optical lens molded product is produced by an injection molding method. More particularly, the present invention relates to a mold structure that facilitates replacement of lens mirror pieces in the case of high-precision, multi-product production such as eyeglass lenses.
[0002]
[Prior art]
In recent years, the demand for plastic lenses has greatly advanced. Plastic lenses are roughly classified into casting-thermosetting allyl resins, transparent thermoplastic resins such as polycarbonate resins and polyacrylic resins produced by an injection molding method.
[0003]
In particular, polycarbonate resin lenses have been attracting attention as a highly safe spectacle lens material that is manufactured by an injection molding method, has a high refractive index, is light, has a good ultraviolet absorption performance, and is shock resistant.
[0004]
A number of methods for producing a finish spectacle lens by injection molding have been proposed, but as a basic problem, a lens mirror surface replacement technique that is compatible with high-mix low-volume production has not been established.
[0005]
For example, the finish lens is generally composed of a lens power matrix of S power + 4.00D to −8.00D and C power 0.00D to −2.00D, and diopters are subdivided in increments of 0.25D. A minimum of a variety of finished lenses is required.
[0006]
In addition, lenses of different diameters are sometimes required to support various types of lenses such as multifocal lenses, progressive focus lenses, semi-finished lenses, etc. It may be necessary to manufacture.
[0007]
In order to manufacture these lenses, optical lens performance is achieved by a combination of optically finished front convex surface and rear concave surface, but in order to cope with manufacturing a very wide variety of lenses, a large number of convex, Must have a concave lens mirror surface. In order to manufacture spectacle lenses by the injection molding method, it is necessary to use these lens mirror surface pieces in a mold and use them as frames, so that various types of lenses can be manufactured by exchanging lens mirror surfaces.
[0008]
However, the types of lenses that can be injection-molded at a time are limited, and in order to meet the demand for a wide variety of spectacle lenses
1) Secure a large amount of molded products in a single production and increase the stock in stock.
2) Many injection molding machines are owned and many types are molded.
3) Easily exchange lens mirror pieces with an injection molding machine to increase the number of product exchanges.
One of the methods is adopted.
It is clear that the method 3) is the most economically preferable, but the interchangeability of the lens mirror piece is an impeding factor. For example, see FIG. 14 of Japanese Patent Publication No. 6-71755 or Japanese Patent Publication No. 61-19409. As shown, the lens mirror piece must be replaced using a retention bolt or the like from the rear or front of the mold plate after the lens mold is once lowered from the molding machine.
[0009]
For this reason, the lens mirror piece replacement method becomes a bottleneck, and the method 1) or 2) is adopted, or even 3) it is uneconomical that a spare mold with a different lens mirror piece is assembled in advance and the mold itself is replaced. Is adopted.
[0010]
On the other hand, a molded product with a remarkably different thickness between the central part and the outer peripheral part, such as a spectacle lens, has a remarkably large shrinkage difference. Temperature control is the most important factor.
[0011]
Various basic methods for forming spectacle lenses have been proposed. For example, an overflow cavity method as disclosed in Japanese Patent Publication No. 61-19409, a multistage compression method as described in Japanese Patent Publication No. 6-71755, and the like. It is disclosed. In these publications, optical lens molds are proposed. However, in many of the proposed methods, the cooling hole is clearly indicated for mold temperature control, but the temperature of the lens mirror piece is indirectly adjusted by heating and cooling the mold plate, not the temperature control of the lens mirror piece. ing.
[0012]
For molding precision molded products such as optical lenses, it is generally most effective to adjust the temperature of the lens mirror piece that is in direct contact with the molten resin. The method of heating the mirror piece with an electric heater or electromagnetic wave is the most effective method for temperature adjustment. There is a method of cooling the molten resin and heating the mold using a circulating fluid such as water or oil. It is most effective and desirable to use hot water that is inexpensive and has a large heat capacity as the circulating fluid.
[0013]
However, when a circulating fluid is used to adjust the temperature of the lens mirror piece, the lens mirror piece and the temperature control circuit become problems, and each joint is sealed with an O-ring. Since the rear part of the lens mirror piece is fixed, the lens mirror piece cannot be easily replaced. Therefore, after cooling the lens mold from the injection molding machine, disassemble it, replace the lens mirror piece, reassemble, and after reattaching, the lens mold is reheated to start molding. Therefore, it is necessary to adopt a method with poor work efficiency. Or, to solve this, a method is also used in which another lens mold incorporating a lens mirror piece is prepared in advance and the temperature is raised, and the lens mold is replaced when changing the product type. It is not efficient in that it requires a spare mold for each machine and is not economical but requires disassembly and reassembly.
[0014]
As described above, the conventional technique has not proposed a mold for efficiently performing a high-quality, multi-product type like a spectacle lens.
[0015]
[Problems to be solved by the invention]
In the conventional optical lens mold, the lens mirror piece, the temperature control piece, etc. have to be fixed from the inside of the mold due to the shape of the parts. Therefore, the only way to replace the lens mirror piece is to lower the optical lens mold and disassemble it, or insert a long bolt or the like from the rear of the mold plate to remove the lens mirror piece.
[0016]
As a result of intensive studies on the method for solving the above-described drawbacks of the conventional method, the present inventors have integrated the lens mirror piece, the circulating fluid circuit piece, and the fixing component even if the circulating fluid is used to adjust the temperature of the lens mirror piece. To make a cartridge, and to fix and / or replace the cartridge from the parting surface or outer surface of the mold plate as it is, a method for obtaining a lens product of good quality and allowing the lens mirror piece to be replaced easily and safely. As a result, the present invention has been completed.
[0017]
In other words, one of the objects of the present invention is that a high-quality molded product has been conventionally obtained, but a temperature control circuit using a circulating fluid that has not been adopted due to the difficulty of exchanging the lens mirror piece is employed. In addition, the present invention provides an injection mold for an optical lens that enables a method for exchanging a mirror piece superior to the conventional method.
[0018]
The second object is to provide a lens molded product of good quality by using the mold of the present invention.
[0019]
[Means for Solving the Problems]
  The present invention relates to an injection molding die that uses a mirror piece as an insert piece method, 1) a lens mirror piece, 2) a temperature adjustment piece, and 3) fixed orMovableA mold for an optical lens characterized by using a pair of cartridges composed of parts for fixing to a mold plate, andManufacturing method of molded article for spectacle lens using the sameRelated to.
[0020]
More specifically, in the present invention, the lens mirror piece and the temperature control piece to be fixed at the rear are separately assembled as a cartridge together with the mold fixing component, and are attached to and detached from the mold as a cartridge. Due to the cartridge structure, it can be easily attached and detached from the part surface and side surface of the mold, and the lens mirror piece can be easily replaced by replacing the cartridge.
[0021]
The optical lens mold of the present invention will be described in detail below.
The lens mirror piece of the present invention is a screw that forms a predetermined shape such as an aspherical surface, multifocal surface, toric surface, cylinder surface, Fresnel surface, etc. on the surface of a material such as metal, resin, ceramic, glass, etc. It has a fixed part such as a hole. However, metal is most suitable from the viewpoint of heat conduction. These production methods include cutting, polishing, electroforming and the like and are not particularly defined.
[0022]
The lens mirror piece of the present invention can be produced by a known method by a polishing method or an electroforming method.
[0023]
The temperature control piece of the present invention is a component for heating or cooling a mirror surface having a flow path through which a heat medium passes. This part includes a portion for sealing the heat medium. Moreover, this part can also have positioning parts, such as a fixed part of mirror surface pieces, such as a bolt hole, and a pin, a spot facing, and a boss | hub. Although the material is not specified, a material suitable for the heat medium must be selected in consideration of heat conduction and workability. For example, when water is used as the heat medium, a SUS-based mold material is preferable, and when oil or fat is used as the heat medium, S55C is preferable. The shape of the flow path of the heat medium is concentric, spiral, radial, etc., but is not particularly defined. The important point is that a sufficient contact area with the heated part of the mold mirror surface is taken, and the contact area is not limited. It is important that the temperature control piece is not deformed or buckled by taking too much.
[0024]
  Fixing orMovableThe component for fixing to the mold plate is a general term for components for fixing or connecting the mirror piece and the temperature control piece assembly to the mold base or the ejector plate of the mold body._.In the case of the present invention, it is desirable to remove the parts that must be removed when replacing the mirror surface from other than the mounting surface to the platen of the molding machine._,Also, it is desirable that the work required for removal can be operated from other than the mounting surface of the molding machine to the platen._.These parts include_,Has a part to fix the mirror piece and temperature control piece assembly_,It consists of parts fixed to the mold body such as mold base, ejector plate, ejector rod, etc._.These parts include_,You may have a flow path through which a heat carrier passes.
[0025]
Moreover, there is no special thing about the mold parts of this invention, The thing of a well-known material and a well-known structure can be used for the injection molding person concerned.
[0026]
  Hereinafter, a method for producing the cartridge will be described in detail. The lens mirror piece is integrated with the temperature adjusting piece via a thickness adjusting spacer as necessary, and fixed with a bolt or the like. The fixed lens mirror piece is integrated with a mold fixing part to form a cartridge. For example, in one example of a part for fixing to a fixed mold, a lens mirror surface piece on the fixed mold side can be easily set by integrating it with a core bush to form a cartridge and fixing the fixed mold with a bolt or the like.MovableAs an example of the cartridge to the mold, a spacer is fixed to the lens mirror surface piece, and the temperature control piece is fixed with a bolt, and if necessary, a spacer for adjusting the compression amount is used.MovableIntegrated with mold fixing parts into a cartridge,MovableBy fixing to the moldMovableMold side lens mirror piece can be set.
[0027]
  There is no particular limitation as a fixing part, and as described above, a part of a mold part such as a core bush may be used.MovableIt may be newly created like a mold. It is also possible to connect to a mold part such as a sliding piece. In short, it is only necessary to select a fixing part and form a cartridge so that the lens specular piece and the temperature control piece are easily fixed to the mold.
[0028]
The temperature adjustment circuit is supplied as a high-temperature circulating fluid from the side of the mold as in a known method, passes through the cartridge, passes through the temperature adjustment piece, passes through the other temperature adjustment piece, or is discharged directly to the side of the mold.・ Pressurized to circulate. As such a high-temperature circulating fluid, high-temperature oils and fats (silicone oil, mineral oil, etc.) of 110 ° C. to 160 ° C. and high-temperature hot water are used, and the high-temperature circulating fluid in the circuit is easily dried when air purging the temperature control circuit. In this respect, high temperature hot water of 110 ° C. to 160 ° C. is preferable, and high temperature hot water of 110 ° C. to 145 ° C. is particularly preferable.
[0029]
  The temperature of the sprue or runner may be controlled by the temperature control circuit of the lens mirror piece. If necessary, each part of the temperature control circuit is sealed with an O-ring or the like. Especially by core compression methodMovableIn order to control the temperature of the lens mirror piece of the mold, it is necessary to introduce / discharge the circulating fluid from the side of the ejector plate.
[0030]
The temperature of the mold may be controlled by a known method, and a circulating fluid, an electric heater, or the like is used, but a circulating fluid is preferable. In some cases, it may be integrated with the temperature control of the lens mirror piece, but in many cases, it is better to perform the temperature control of the lens specular piece and the temperature control of the mold separately.
[0031]
Any method may be used for fixing the cartridge and the mold, and various known methods are employed. For example, a method of mechanically fixing such as a bolt, a taper pin, a wedge, a split, an air chuck, or the like, or an electrical fixing method using an electromagnet or the like can be considered. Commonly 1) The circulating fluid temperature control circuit between the cartridge and the mold can be connected sufficiently. 2) The cartridge can be fixed to or removed from the mold by operation from the part surface or the outer surface of the mold. If necessary, it is preferable to perform operation by providing a guide hole or the like in the mold as necessary. In this way, the cartridge can be fixed and removed without disassembling the mold, and the lens mirror piece can be easily replaced. Since the lens mirror piece is usually circular, it is often removed from the mold part surface. However, if the fixing jig shape is designed to be rectangular or square, it can also be removed from the mold side.
[0032]
In this way, the greatest advantage of the present invention is that the lens mirror piece can be exchanged in the cartridge state without removing the mold from the injection molding machine. It is possible to exchange. Therefore, it is much more efficient in terms of time and cost compared to the method of disassembling and resetting the mold as in the conventional method and the method of replacing with a spare mold incorporating another lens mirror piece.
[0033]
In order to maximize the effects of the present invention, it is desirable to replace the cartridge while the mold is set in the injection molding machine and without cooling while the mold is used. In particular, when molding is performed at a high mold temperature of 110 to 160 ° C. like polycarbonate resin, hot water is ejected unless the cartridge is removed after the hot hot water in the temperature control circuit is completely purged. For this purpose, it is necessary to exclude the circulating fluid from the temperature control circuit in the mold. However, it is preferable to block and compress the circulating fluid between the mold of the present invention and the circulating pump of the circulating fluid. If a high-pressure gas body such as air is introduced to purge the circulating fluid in the temperature control circuit, the cartridge can be easily replaced at a high temperature. In addition, when the circulating fluid is high-temperature hot water, there is an advantage that the high-temperature hot water is purged and the inside of the temperature control circuit can be dried.
[0034]
More preferably, if the cartridge to be replaced is heated in advance, the start-up time for the product replacement after the cartridge replacement can be greatly shortened. This not only improves efficiency by shortening the replacement time, but also prevents the formation of a carbonized layer due to deterioration of the thermoplastic resin in the cylinder of the injection molding machine, and is also highly effective from the quality of optical lens molded products.
[0035]
As a secondary effect, the lens mirror piece has an optically polished or electroformed surface that is optically accurate. Therefore, when replacing the lens mirror piece, great care must be taken not to damage the lens mirror piece surface. is there. In the cartridge system, there is no mold disassembly / attachment, and the lens mirror piece can be handled in a clean place, and rarely damages the valuable lens mirror piece. In some cases, it may be necessary to reassemble the lens mirror piece after test molding due to defects (scratches, spiders, dirt, etc.) of the built-in mirror piece or depending on how the spacer is adjusted. Even in such a case, the method of the present invention can be corrected in a short time, and exhibits great advantages in production management and quality control. Furthermore, in the conventional method of mirror face piece replacement, the amount of work was such that the mold was lowered by two to three people, but the method of the present invention is safe because the replacement work can be done safely in a short time by one person. It is also effective from management.
[0036]
As described above, in the method of the present invention, it is possible to easily replace the mirror piece at a high temperature while being incorporated in the molding machine without cooling and disassembling the mold. Usually, in the conventional methods, it takes several hours to change the type. It can be completed in a few minutes to a few tens of minutes, remarkably improved in efficiency, and can cope with multi-product production which was most important in the injection molding of spectacle lenses.
[0037]
The mold for optical lenses of the present invention is particularly useful for molding eyeglass lenses. Examples of molding materials for such spectacle lens molded products include transparent thermoplastic resins such as polycarbonate resins and polymethyl methacrylate resins. In particular, a polycarbonate resin is preferable from the viewpoint of transparency and moldability.
[0038]
The polycarbonate resin used in the present invention is an aromatic polycarbonate resin obtained by reacting a dihydric phenol and a carbonate precursor. Specific examples of the dihydric phenol used here include 2,2-bis (4-hydroxyphenyl) propane (commonly known as bisphenol A), bis (4-hydroxyphenyl) methane, and 1,1-bis (4-hydroxyphenyl). ) Ethane, 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) octane, 2,2-bis (4-hydroxyphenyl) phenylmethane, 2,2-bis (4 -Hydroxy-3-methylphenyl) propane, 1,1-bis (4-hydroxy-3-tert-butylphenyl) propane, 2,2-bis (4-hydroxy-3-bromophenyl) propane, 2,2- Bis (4-hydroxy-3,5-dibromophenyl) propane, bis such as 2,2-bis (4-hydroxy-3,5-dichlorophenyl) propane Hydroxyaryl) alkanes, 1,1-bis (hydroxyphenyl) cyclopentane, bis (hydroxyphenyl) cycloalkanes such as 1,1-bis (hydroxyphenyl) cyclohexane, 4,4′-dihydroxydiphenyl ether, 4,4 Dihydroxyaryl ethers such as' -dihydroxy-3,3'-dimethyldiphenyl ether, dihydroxydiaryl sulfides such as 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfide, 4 Dihydroxydiaryl sulfoxides such as 4,4′-dihydroxydiphenyl sulfoxide, 4,4′-dihydroxy-3,3′-dimethyldiphenyl sulfoxide, 4,4′-dihydroxydiphenyl sulfone, 4,4′-dihydroxy-3,3 ′ -Dimethyldi And dihydroxydiaryl sulfones such as phenyl sulfone. These dihydric phenols may be used alone or in combination of two or more.
[0039]
Of the dihydric phenols, 2,2-bis (4-hydroxyphenyl) propane (bisphenol A) is preferably used as the main dihydric phenol component, particularly 70 mol% or more, particularly 80% of the total dihydric phenol component. The thing whose mol% or more is bisphenol A is preferable. Most preferred is an aromatic polycarbonate resin in which the dihydric phenol component is substantially bisphenol A.
[0040]
The basic means for producing the polycarbonate resin will be briefly described. In the solution method using phosgene as a carbonate precursor, the reaction of a dihydric phenol component and phosgene is usually performed in the presence of an acid binder and an organic solvent. Examples of the acid binder include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, and amine compounds such as pyridine. As the organic solvent, for example, halogenated hydrocarbons such as methylene chloride and chlorobenzene are used. In addition, a catalyst such as a tertiary amine or a quaternary ammonium salt can be used for promoting the reaction, and a terminal terminator such as an alkyl-substituted phenol such as phenol or p-tert-butylphenol is used as a molecular weight regulator. It is desirable to use it. The reaction temperature is preferably 0 to 40 ° C., the reaction time is several minutes to 5 hours, and the pH during the reaction is preferably maintained at 10 or more.
[0041]
In the transesterification method (melting method) using a carbonic acid diester as a carbonate precursor, a predetermined proportion of a dihydric phenol component and a carbonic acid diester are stirred with heating in the presence of an inert gas, and the resulting alcohol or phenols are distilled. It is a method to make it come out. The reaction temperature varies depending on the boiling point of the alcohol or phenol produced, but is usually in the range of 120 to 300 ° C. The reaction is carried out while distilling off the alcohol or phenol produced under reduced pressure from the beginning. Moreover, in order to accelerate | stimulate reaction, a normal transesterification reaction catalyst can be used. Examples of the carbonic acid diester used in the transesterification include diphenyl carbonate, dinaphthyl carbonate, dimethyl carbonate, diethyl carbonate, dibutyl carbonate, and the like, and diphenyl carbonate is particularly preferable.
[0042]
The molecular weight of the polycarbonate resin used in the present invention is preferably 17,000 to 30,000, particularly preferably 20,000 to 26,000 in terms of viscosity average molecular weight. Eyeglass lenses are precision molded, and it is important to accurately transfer the mirror surface of the mold to give the specified curvature and power. A low-viscosity resin with good melt flow is desirable, but if it is too low The impact strength that is characteristic of polycarbonate resin cannot be maintained. The viscosity average molecular weight (M) mentioned here is obtained by using an Ostwald viscometer to determine the intrinsic viscosity [η] of a solution measured at 20 ° C. using methylene chloride as a solvent.
[Η] = 1.23 × 10^-FourM^0.83
It is requested from.
[0043]
A release agent can be incorporated into the polycarbonate resin of the present invention, and this gives favorable results. Saturated fatty acid esters are generally used as mold release agents, for example, monoglycerides such as stearic acid monoglyceride, lower fatty acid esters such as stearic acid stearate, higher fatty acid esters such as sebacic acid behenate, pentaerythritol tetrastearate, etc. Of erythritol is used in an amount of 0.03 to 1 part by weight per 100 parts by weight of the polycarbonate resin. Moreover, you may mix | blend 0.001-0.1 weight part of phosphite ester-type heat stabilizers with respect to 100 weight part of polycarbonate resin as needed. Phosphite-based thermal stabilizers include tris (nonylphenyl) phosphite, triphenylphosphite, tris (2,4-di-tert-butylphenyl) phosphite, tetrakis (2,4-di-tert-butyl) Phenyl) -4,4′-biphenylenediphosphonite, bis- (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol-di-phosphite, bis (2,4-di-tert-butyl) Phenyl) pentaerythritol-di-phosphite, tris (ethylphenyl) phosphite, tris (butylphenyl) phosphite and tris (hydroxyphenyl) phosphite are preferred, and tris (nonylphenyl) phosphite and tetrakis (2,4 -Di-tert-butylphenyl) -4,4'-biphenyle Diphosphonite is particularly preferred.
[0044]
For the purpose of improving weather resistance and cutting harmful ultraviolet rays, the polycarbonate resin of the present invention may further contain an ultraviolet absorber. Examples of such ultraviolet absorbers include benzophenone ultraviolet absorbers represented by 2,2′-dihydroxy-4-methoxybenzophenone; for example, 2- (3-tert-butyl-5-methyl-2-hydroxyphenyl) -5. -Chlorobenzotriazole, 2- (3,5-di-tert-butyl-2-hydroxyphenyl) -5-chlorobenzotriazole, 2,2'-methylenebis [4- (1,1,3,3-tetramethyl Butyl) -6- (2H-benzotriazol-2-yl) phenol], 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole and 2- (3 , 5-di-tert-amyl-2-hydroxyphenyl) benzotriazole is exemplified by benzotriazole-based ultraviolet absorbers, These can be used alone or in combination of two or more. Of these ultraviolet absorbers, benzotriazole ultraviolet absorbers are preferred.
[0045]
The polycarbonate resin of the present invention may further contain a bluing agent in order to counteract the yellowishness of the lens based on the polycarbonate resin or the ultraviolet absorber. Any bluing agent can be used without any problem as long as it is used for polycarbonate resin. In general, anthraquinone dyes are preferred because they are readily available.
[0046]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to examples. In addition, an Example does not limit the scope of the present invention.
[0047]
  FIG. 1 shows a schematic view of the entire mold of the present invention. The mold will be briefly described. First, a fixed mold side cartridge 4 (thick line portion) having a fixed mold side lens mirror surface piece 2 and a fixed mold side temperature adjusting piece 3 in a fixed mold side die set 1 is fixed with a cartridge fixing bolt 5. Fix it. Next, when changing the diameter of the mirror piece,MovableMold andMovableAfter exchanging the adjustment jig 30 with the mold side cartridge and fixing the adjustment jig 30 with the bolt 31 for the adjustment jig,MovableMold side lens mirror piece 8 andMovableHas mold side temperature control piece 9MovableInsert the mold side cartridge 10 (thick line part) into the adjustment jig 30 and beside the ejector plate 6.MovableOn the mold side die set 7MovableThe mold side cartridge 10 is fixed with the air chuck 11. The fixed mold with this cartridge installedMovableThe cavity 13 is formed at the position of the parting surface 12 with a mold. The mold having the fixed mold side cartridge 4 and the fixed mold side cartridge 10 is suitable for injecting a thermoplastic resin (especially polycarbonate resin) into the cavity 13 to mold an optical lens, particularly a spectacle lens. is there.
[0048]
  FIG. 2 shows a conventional optical lens mold. First, a part having the adjustment spacer 33 and the fixed mold side lens mirror piece 2 is inserted into the side die set 32 on the fixed mold side, the back die set 34 is set, and fixed with the fixing bolt 14 for the fixed mold. Next to the ejector plate 6MovableOn the mold side die set 7MovableParts with mold side lens mirror piece 8MovableIt is fixed with a molding hub 15. This fixed mold andMovableEach mold is temperature-controlled by an electric heater from the lower part or side part of the mold.
[0049]
FIG. 3 shows one method for fixing the fixed mold side cartridge 4 of the present invention to the fixed mold. The fixed mold side lens mirror surface piece 2 is integrated with the fixed mold side temperature adjusting piece 3 and the core bush 17 via a spacer 16 to form a cartridge, and is fixed to the fixed mold 18 with the cartridge fixing bolt 5. Reference numeral 19 denotes a temperature control circuit. By removing the cartridge fixing bolt 5, it can be easily replaced with another fixed mold side cartridge 4.
[0050]
FIG. 4 shows one method of fixing the magnetic body 20 to the fixed mold side lens mirror piece 2 and the fixed mold side temperature adjusting piece 3 and fixing it with an electromagnet incorporated in the mold. Can be fixed or detached.
[0051]
  FIG.MovableOne of the methods of fixing to a mold is shown.MovableMold side mirror piece 8, thickness adjusting spacer 21,MovableThis is an example of a cartridge in which the mold-side temperature adjusting pieces 9 are sequentially fixed with bolts and then integrated with a fixing component 23 via a compression amount adjusting spacer 22. This cartridge uses a mechanical catch such as a taper pin, a wedge, a split, an air chuck or the like on the notch 24 of the fixing part 23.MovableFixed to the mold.
[0052]
  FIG. 6 illustrates a method of fixing to the ejector plate 6 using a sliding piece. The slide core 25 is integrated as a fixing part, and a cutout portion 24 is provided in the same manner as in FIG. 4, and is connected and fixed to the ejector plate using the same method. Of courseMovableFixing to the mold and the ejector plate requires a fixing jig having a structure corresponding to the notch shape and the fixing method.
[0053]
  FIG. 7 shows an example in which a slide split is used as a fixing jig. An auxiliary plate 26 is attached to the ejector plate 6 and a slide guide groove is provided in the auxiliary plate. When the sliding piece fixing jig 27 is set in the slide guide groove 28 and is operated from the guide hole provided on the side surface of the mold plate, and the bolt 29 attached to the sliding piece fixing jig 27 is turned, the jigs on both sides are inward. And is fixed to the catching part of the sliding piece 25,MovableThe mold side cartridge is fixed to the ejector plate 6. Hereinafter, the above-described method such as a wedge can be used in the same manner.
[0054]
    [Example 1]
  After the four-piece frame type mold is attached to the lens injection molding machine having the injection compression function, the fixed mold side mirror piece is attached as a cartridge by the method shown in FIG. 3, and the method shown in FIG.MovableThe mold side lens mirror piece was assembled into a cartridge and assembled. A polycarbonate resin spectacle lens was injection compression molded at a molding temperature of 310 ° C. using high-temperature hot water of 130 ° C. for lens mirror surface temperature control and 140 ° C. for mold temperature control. The obtained spectacle lens was less distorted and the reflected image of the fluorescent lamp was not disturbed.
[0055]
After completion of molding, the mold temperature was left as it was, and compressed air was blown from a part of the temperature control circuit to completely purge the circulating hot water in the mold. After that, after removing the cartridge and inserting another eight previously set cartridges and connecting the temperature control circuit, the injection molding of the next type could be started up 20 minutes after the completion of molding.
[0056]
[Comparative Example 1]
As a result of molding the spectacle lens using the conventional fixed mold shown in FIG. 2, the spectacle lens molded product has defects such as optical distortion in the polarizing plate observation, and the image of the reflected image of the fluorescent lamp is slightly on the outer periphery. Disturbance was seen and the quality of the eyeglass lens obtained in Example 1 was inferior. As a result of cooling this mold and removing it from the injection molding machine, disassembling and exchanging the lens mirror surface, mold cooling → removal → lens mirror surface replacement → installation → mold injection temperature rise to start the next injection molding It took about 4 hours to complete. Furthermore, a large amount of resin and time were required for complete purging of internal foreign matters (charcoal fires, etc.).
[0057]
【The invention's effect】
As is apparent from the above detailed description of the invention and the examples, the optical lens mold of the present invention can obtain a high-quality lens in injection molding of a spectacle lens and the like, and can be exchanged in a short time. Therefore, it is particularly useful when efficiently producing a variety of products.
[Brief description of the drawings]
FIG. 1 is a schematic view of a mold according to the present invention.
FIG. 2 is a schematic view of a conventional fixed mold.
FIG. 3 is a schematic view of a fixed mold side cartridge.
FIG. 4 is a schematic diagram of a cartridge fixed with an electromagnet in which a magnetic body is attached to a mirror piece and a temperature control piece and is incorporated in a mold.
FIG. 5 is a schematic view of an operating mold side cartridge using a fixed part.
FIG. 6 is a schematic view of an operating mold side cartridge using a sliding piece.
FIG. 7 is a schematic view showing a portion using a slide split as a jig for fixing the working mold side cartridge.
[Explanation of symbols]
1. Fixed mold side die set
2. Fixed mold side lens mirror piece
3. Fixed mold side temperature control piece
4). Fixed mold side cartridge
5). Cartridge fixing bolt
6). Ejector plate
7). Working mold side die set
8). Working mold side lens mirror piece
9. Operating mold side temperature control piece
10. Working mold side cartridge
11. Air Chak
12 Parting surface
13. cavity
14 Fixing bolt for fixing mold
15. Fixed hub for working mold
16. spacer
17. Core bush
18. Fixed mold
19. Temperature control circuit
20. Magnetic material
21. Thickness adjustment spacer
22. Compression adjustment spacer
23. Fixing parts
24. Notch
25. Sliding core
26. Auxiliary plate
27. Slide piece fixing jig
28. Slide guide groove
29. bolt
30. Adjustment jig
31. For adjustment jig
32. Bolt side die set
33. Adjustment spacer
34. Back die set

Claims (4)

In the injection mold using the mirror piece as the insert piece system, 1) a lens mirror piece, 2) a temperature adjustment piece, and 3) a pair of cartridges consisting of fixed parts to a fixed or movable mold plate are used. Characteristic mold for optical lenses. The optical lens mold according to claim 1 , wherein the circulating fluid of the temperature control piece is high-temperature hot water or oil / fat at 80 ° C to 160 ° C, and a device for introducing a high-pressure gas into the high-temperature hot water / oil / fat circulation path is attached. A method for manufacturing a spectacle lens molded product, wherein the spectacle lens molded product is manufactured using the optical lens mold according to claim 1 . 4. The method for producing a spectacle lens molded article according to claim 3 , wherein the spectacle lens molded article is formed of a polycarbonate resin.

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