TWI344897B - Moulding process - Google Patents

Description

1344897 IX. Description of the Invention: Field of the Invention The present invention relates to a method and apparatus for producing a plurality of ophthahic lenses, such as a soft contact lens, and an ophthalmic lens produced. [Prior Art] Background of the Invention Conventionally, a method for producing an ophthalmic lens is to form a lens blank by polymerizing a liquid monomer in a mold, and then mechanically performing the lens blank. Lathe processing, "for the finished lens, and reduce the lens to remove fatigue. This method is labor intensive and expensive.一种 A two-sided casting molding (dscm, double cast inging) method has been developed previously. In general, these methods involve the initial fabrication (by molding) of the male and female molds of the earlier use.沉积 Deposit the: state monomer into the master mold and pair the male mold with the master mold: . Then, the monomer is heated and solidified to form a compound lens (the term "curing" means 'cured material 疋..., method> gluten in the solvent - Wei...疋 dissolved 'and therefore the terminology, contains more specific terms, such as polymerization,: use, thinning, etc.). The lens is removed from the mold, and at:::' is absent to extract unreacted monomer and/or solvent. The money is removed and the lens is packaged into a final package. 5 1344897 It should be noted that the controllable molding method in this D Γ M — #, 里 JJbiM method is for the single-purpose model, rather than the lens itself. Molded. The most common way to produce a single-purpose & + upper-seat cookware is to produce it in two using an insert that is mounted on two platforms and that is removably mounted and precisely machined. Between platforms. The change in mold shape can be accomplished by changes in the insert in the molding platform (in order to produce lenses with different optical qualities). Typically, the insert is designed over a precision lathe and polished to remove the flaws from the surface. Some particular lens optical qualities are determined by controlling the orientation of the male to female molds. Therefore, in the DSCM method, the shape determining the shape and the magnification of the final lens is the shape of the mold that is discarded. U.S. Patent No. 5,508,3,17, the disclosure of which is incorporated herein by reference to the entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire portion What is requested is that the invention has the advantage of being able to omit the steps of cleaning and extracting standard DSCM. Other improvements that can be provided to the DSCM include the removal of one of the reusable molds and at least one mold that is transparent to the uv. UV curing. W0 98/42497 discloses a lens which will be produced by the DSCM method, which is cured by UV alone. US 4,673,539 and US 4,786,446 each disclose a different manufacturing method which includes the creation of a shaped thermoplastic hydrogel. a gel precursor, 6 8 1344897 by the polymerization of a specific form of uncrosslinked polymer (a polymer comprising a product of an ethylenically unsaturated monomer bearing at least one trihaloacetoxy substituent) Thermal formation (therm〇f〇rming), followed by solvation (solvolyzmg) of the precursor in the presence of a diluent to form a polymerization It objects, and the lenses for hydration, to provide the ophthalmic lens. The present invention is a method request, and to produce a high water absorption properties can be controlled by the shape of the object.

The DSCM method suffers from the problem of quality change in the manufacturing process due to the control of the quality of the mold in the two-step casting secret and the variability in the curing method. In the practical context of commercial production processes, the curing process always depends on changes in the monomer mixture and changes in the composition of the monomer mixture. The curing method of the f is also dependent on the change in the curing rate due to fluctuations in the energy of the curing source (normally hot curing). All of the previous techniques have suffered from the problem of manufacturing efficiency, and their efficiency is a lot of batch methods that require many human participation. The downside is that for every method step, the trained operator needs to be effective. Conventional manufacturing methods are carried out. Because of this, the manufacturing cost of ophthalmic lenses will increase relatively. It is an object of the present invention to provide a method of producing an ophthalmic lens having improved manufacturing efficiency compared to prior art methods. In particular, the method of the present invention provides improvements in production consistency and quality, and reduces the number of steps required for the method as compared to prior art methods. Another object of the present invention is to reduce the amount of material consumed for molding/smoothing of ophthalmic lenses, and in this way, to reduce the environmental impact of the 3 molding and curing methods. Another purpose of this invention is to reduce the impact of molding and curing methods on the environment by reducing the amount of wet chemicals and associated chemical waste products (as compared to prior art methods). SUMMARY OF THE INVENTION The present invention overcomes the above mentioned problems by providing a means for producing a plurality of soft contact lenses, wherein the present invention provides a solid, substantially dry material. It is water soluble above a certain temperature. Then, through the control of physical force, applied to the material, the material is formed into a plurality of formed lens blanks, and then below this specific temperature (above the temperature, the 枓 system is 可At the temperature of the water-soluble, the formed lens blank is subjected to water to form a plurality of soft contact lenses. The present invention also provides a device for producing a plurality of soft contact lenses, which includes a forming tool for applying a physical force controlled by a @ku 4 to a 4-plate material. The button α has formed a plurality of formed lens embryos, and a thin sheet material transporting work. The soil, ^ 6 sea transport tool includes a driven and/or driven roller tool for transporting the sheet material. . In the comparison of the method provided by the present invention, in the specific grief of the right, the "characteristic / dish degree" is the material system.

The temperature of Nf is not as large as 1344897 and about 5 〇 °c is about 6 5 °C. In the method of the present invention, in other specific aspects, the material may be: - polyvinyl alcohol, or a copolymer of - polyvinyl alcohol and polyethylene ethyl ester, or - polyethylene maleic anhydride, or a copolymer of t-methyl-per-propyl-propylcellulose or ~methacrylate, or an ethyl acrylate having ethylene or a hydroxy derivative thereof, or a copolymer of polyvinyl alcohol and polyvinyl ethyl ester The nature of the hydrolysis (measured by the chemistry) is at least 9.6 moles based on the original polyvinyl alcohol. In a more desirable embodiment of the method of the invention, the material is a consistently uncrosslinked polymer comprising crosslinkable groups. In this particular aspect, prior to hydration step C, high energy is applied to the formed lens blank and the polymer is crosslinked to achieve a predetermined desired crosslink density. The polymer is also formulated to include additives that will react with the application of high energy to improve cross-linking efficiency. "High energy" may be any of the following types: an electron beam irradiation, or a gamma irradiation, or - microwave irradiation, or an ultraviolet light irradiation, or an infrared light irradiation, or 9 thermal irradiation, or ultrasonic irradiation. . After the method of the present invention wins step B, among the other specific embodiments, at least part of the physical blank is formed: the material is used as a thin plate material, and the formed mirror is used as a dry: On the sheet material. This can make the organization. For this method another 2 "quality / method for carrying the cutting of the lens blank for the forming of the lens blank: a hope of success is to use - laser blank from the sheet: except: 11 - appropriate point Above, the formed lens is physically formed in a step R ^ to be performed, such as: by using a different method to heat the formation method, or vacuum forming method, or pressing method, or - hot molding method, or - cold Molding, or compression molding, or ~ injection molding. Preferably, the preferred heat forming of the present invention has a temperature in the n ssm sub-material that is added to the softening temperature of the material, for example, the heat formation of the two materials is possible, but The physical integrity of the material is maintained under material (iv). Then, the formed lens embryo is thermally formed by applying a force to the material of the twisted material. This physical force may be applied by pressing m' between two formations or 10 1344897. : Some preferred embodiments..., the physical formation step uses t. The material is placed between the molds, together, and the knives are pressed to form a plurality of formed lens blanks. Further, the characteristics of the step-by-step include the application of high energy radiation, or gamma irradiation, or microwave irradiation of the beamlets, lens blanks or lenses for sterilization. d' will be transferred to a plurality of final packages in some further specific aspects. These final packages can be pre-sterilized. It may likewise comprise a sterile or sterile solution, and the lens is hydrated in step e. The material of the formed lens blank in the sample field can be subjected to a chemical reaction such as hydrolysis in the final package. In a particularly preferred embodiment, all of the method steps after step β are carried out without further human contact or manipulation. :::: The method can be continuous or semi-continuous..., automatic or semi- From: ground... In some specific aspects, 'there is only inspection of quality control on the formed lens blank. These tests can be visible to the naked eye or an optical system can be used. 5 The present invention also provides a method of producing a plurality of ophthalmic lenses comprising (a) providing a substantially non-crosslinked polymer comprising a crosslinkable group; (b) physically polymerizing the lens Substance formation: complex:: in the ophthalmic lens; and (C) the amount applied to the density of the plurality of ophthalmic 8 11 lenses. Crosslinking the polymer into a predetermined desired cross-linking and in a preferred embodiment of the apparatus of the present invention, the forming apparatus includes a plurality of mounted structures or platforms to enable Pressing: forming the sheet material into a plurality of shaped lens blanks: the plurality of formations or platforms 'to add a heating tool to heat the ~-plate material' to make the formation method It's easier. Among the specific aspects of a certain two-story, the plurality of platforms are connected in a movable 2 manner with a plurality of male and female models. These diterpene and maternal inserts are formed into a suitable shape to form the formed lens blank to the desired optical specifications. The insert can be installed so that pressure (positive or negative) can be applied by these inserts. In a preferred embodiment of the apparatus of the present invention, the apparatus further includes an armoring tool to transfer the formed lens blank to the final package. This packaging tool can be installed to package in a substantially sterile loop. In a particularly preferred embodiment, the apparatus of the present invention also includes a removal tool for removing the formed lens blank from the sheet and for forming the edge of the formed lens blank . This removal tool can be a laser cutting tool such as a C02 laser. Spoons are provided by the apparatus of the present invention, and some preferred embodiments, when used, also employ tools to apply high energy to the formed lens blank or to the formed lens blank. The soft contact lens formed on the material. This high energy application tool can be an electron beam irradiation tool. 12 8 1344897 The present invention has a number of advantages over prior art methods for producing ophthalmic cymbals. When using the present invention, there is no loss in the accuracy of the shape of the lens, because of the shrinkage produced by the mold which allows cooling in the prior art method, and the shrinkage which occurs in the initial monomer volume due to polymerization ( With approximately 16% shrinkage, it is difficult to accurately control the degree of shrinkage. ^ When using the present invention, it is not necessary to store and store a single-use mold list that is not currently in use. Since it is not necessary to produce a mold that is discarded when it is used up, it is not a scratch of the final product. Thus, the waste produced by the present invention is greatly reduced. Due to the use of easier to control method steps, the lenses produced by the present invention have improved lens magnification accuracy, improved surface quality, and warp, as compared to those made using prior art methods. Improved magnification consistency. Some particularly specific aspects of the present invention provide improved sterilization, packaging, and in-line inspection steps that are superior to prior art manufacturing methods. These improvements can also reduce the manufacturing area required. Compared to the conventional method of using a reusable glass mold, the advantage of this month is that it is not necessary to frequently perform mold cleaning and mold cleanliness inspection. In the conventional method of using UV curing alone, uv absorption J cannot be incorporated into the lens because these inhibit the polymerization method. In the present invention, when it is desired to create a lens comprising such a UV absorber, irradiation in the form of no UV can be used. 13 8 1^44897 Other aspects of the present invention will be further described in the following detailed description and drawings, in which a specific embodiment of the invention is described. The method of contact lenses, the use of contact lenses as a specific example of ophthalmic lenses, and the use of: e-beam illumination as a specific example of the manner of high energy applications. [Embodiment] Detailed Description of the Invention

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic diagram showing a specific aspect of the present invention. A roll of polymer in the form of a sheet is provided and conveyed to a hot forming zone 14 . Before entering the heat-forming region, the polymer sheet was inspected for obvious defects such as cracks by means of an automatic view, because it caused an unsatisfactory final product. ° Xuan Ju σ can be Mowiol® (material manufactured by ciariant GmbH), which is a copolymer of polyethylene glycol and polyvinyl acetate, in which the degree of hydrolysis (measured by saponification) The system is 'at least 96 mol% of the initial polyvinyl alcohol. The 5 kel polymer sheet is heated to a temperature at which the polymer can be easily "shaped" into a desired shape, as defined by the inserts on the tanning platforms (3 and 9). And the polymer sheet still maintains sufficient strength to allow it to be applied by the method. The polymer sheet is then passed through the heat-forming region, which contains a platform of optical quality inserts (not shown) (3 and 9), the polymer sheet is shaped into the desired form. Depending on the properties of the polymer sheet, the insert and the platform can be cooled or heated in accordance with the crucible to obtain the desired flow and clarity in the formed part. Use pressure or vacuum 'through the platform and the insert, the same J to use" to achieve the desired shape. The optical insert and the i-body (known in the middle of the platform) are designed such that the shaped part is not completely separated from the original polymer sheet, thus making the forming method-a After 70% of the attacking method, the formed part will move forward together with the έ 聚合物 polymer sheet 1 2 .

Then, the formed component is inspected by the automatic observation system 4 to see if it is defective. The polymeric sheet can then be stored with the shaped part for use in a crucible or it can be immediately processed at base 5 by a sterile electron beam as a continuous or semi-continuous process. If the provided polymer is not completely crosslinked, the polymeric sheet and the shaped part can be controlled to be exposed to an electron beam such that the polymer achieves the desired degree of crosslinking and will also be as sterile as desired. degree. Separating the shaped part from the polymeric sheet and placing the shaped part in a final package in a sterile environment, as shown in Figure 5, which does not occur at base 5, although it should be noted that packaging is possible It will be carried out on a base away from electron beam irradiation (not shown). The final package is manufactured and/or processed on the base 6 to be effectively sterilized and maintained in an environment capable of maintaining it (and the shaped part) in a sterile state. The final package is conveyed 13 to a position so that the formed part can be transferred to the final package. Delivering the final package of the shaped part to the sterile environment to a dosing position (dosing p〇siti〇n) 7, adding 8 15 1344897 to the position with a sterile or sterilized packaging/hydration solution, and It is controlled at a temperature below the temperature at which the polymer will become water soluble. The final wrapper, solution, and formed parts on base 8 (also in the sterile area) are then sealed using a layer of sterile foil, after which the treated area for the final mark " is left. "〇phthalmic 1 enses" as used in this specification means any medical or vision correction device used in eye-related environments, including contact lenses, intraocular lenses. ), corneal onlays and ocrneal inlays, ocular drug delivery devices, eye wound healing devices, and the like. The cross-linking portion of the lens manufacturing method includes exposing the shape of the dry lens made of the polymer to a high energy source. As used herein, "high energy" means many forms and includes, but is not limited to, sources of heat, I.R., U.V., microwave, gamma, supersonic, and electron beam illumination. Φ "Crosslinking" as used in this specification is used to describe a method in which a soluble polymer is converted into a crosslink through the formation of bonds between polymer chains, ie, crosslinks. Insoluble form. It will be apparent to those of ordinary skill in the art of the invention that the insoluble form comprises, in addition to the crosslinked structure, a structure of a conventional graft polymer or entangled polymer. One of the purposes of cross-linking, as used in this specification, is to tailor the cross-linked lens to form a stable wet mirror 1344897 piece and at the same time provide correction to the user's magnification. For water soluble polymers, the crosslinked polymer is a conventional hydrogel. ' "Polymer" as used in this specification means a material for the initial lens shape, and includes a copolymer, a mixture of polymers, and an interpenetrating network system (1S J, already part). a cross-linked polymer system, a polymer to aid in the crosslinking reaction to add an additive, such as to reduce UV transport, to achieve therapeutic goals, to add color for decorative purposes, and the like. In any cross-linking reaction ^ j 1 thinking about the exposure: change depending on the composition of the polymer and the required properties. The final lens is one of the best specific aspects of the ophthalmic lens (aqueous contact lens). It may include a water content of from 20 to 75% by weight. Secondly, it is assumed that the crosslink density of the lens for a particular polymer: the water content of the lens, that is, the higher the crosslink density: less In the other embodiments, the degree of crosslink density required can be achieved at the same time by exposure to radiation. ..., 圏: Generally speaking, all cross-linking methods are desired. Enough, preferably less than 1 minute, more preferably less than 4 minutes, ^ θ gossip 'knife clock, better than less than knives. In some polymer formulations '-J - At - z. j This is more than one clean: to the required quality and performance requirements. At the same time, it must also ensure that the staff inserts the method and the safety of the environment. The level of measurement used in the cross-linking method may be lower than the level of 17 in the early step; this is compensated by multiple steps. Exposure to an electron beam or gamma light Radiation cross-linking

CD has been added to the additive (known prorads) from 0.2 to 5% by weight to the A field to achieve the purpose of promoting crosslinking. These compounds may be a vinyl or propylene-based compound of a polynomethylene group such as a triallyl ethylene propylene oxide propylene diisocyanate or a pentaerythritol tetramethacrylate. Koda Shot 1 depends on the reaction of the irradiated polymer and the extent of ΡΓ〇Γ3 < 1 (if any). Typical dosages range from 20 to 80 〇kGy', preferably from 20 to kGy, such as from 2 to 2 〇〇kGy, especially from 40 to 12 〇k (}ye finished and packaged lenses, also It can be sterilized by other appropriate methods (eg + gamma, steam, etc.) However, the method of disinfection and elimination must be smashed, smeared; step on the shell should be carefully selected 'to avoid severely changing the lens or packaging [Characteristics or performance of the drawings] Brief description of a contact lens manufacturing apparatus according to an embodiment of the present invention. [Description of main components] 1 · Polymer 2 · Automatic observation system 3. Molding platform 4. Automatic observation system 5 · Base 6 · Base 1344897 7 · Batching position 8. Base 9 · Molding platform 1 2 · Polymer sheet 1 3 · Transport 1 4 · Heat forming area

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Claims (1)

1344897 97. 7. -2 X. Patent application scope: The following steps: a method for manufacturing a plurality of soft contact lenses, which comprises providing a solid, substantially dry sheet material as A; through physical force control, Applied to the material, the material is formed into a plurality of shaped lens blanks; C. The formed lens blank is hydrated to form a plurality of soft contact lenses; Immediately after the formation of step B, at least a portion of the plurality of formed lens blanks remain adhered to the sheet material. According to the method of manufacturing a plurality of soft invisible 艮* brothers according to Item 1 of the patent application scope, the solid and substantially dry sheet material is water-soluble at a specific degree or more, and the plurality of The formed lens blank is hydrated at a temperature below this particular temperature. 3 A method of manufacturing a plurality of soft contact lenses according to the scope of claim 2, wherein the specific temperature is about 5 (TC. 4 according to the method of claim 2, the method of manufacturing a plurality of soft contact lenses, wherein the specific temperature A method of manufacturing a plurality of soft contact lenses according to any one of claims 1 to 4, wherein the material is selected from the group consisting of polyvinyl alcohol, or polyvinyl alcohol and polyethylene B. Copolymer of ester, or polyethylene maleic anhydride, or copolymer of polymethyl-hydroxy-propyl-cellulose or methacrylate, or ethyl acrylate having ethylene or its hydroxy derivative In the group consisting of 20 1344897 97. 7, r2 6 · According to the method of claim 第1 to 4, φ红一W Τ1壬, a method for producing a plurality of soft contact lenses, wherein the material system The copolymer of polyethyl k-polyvinyl ethyl ester, wherein the hydrolysis is carried out, and the measurement of the polymerization and the molecular weight of the raw polyvinyl alcohol is at least 9.6 % based on the original polyvinyl alcohol. 7. According to the patent claims 1 to 4 4 items of responsibility A method of making a plurality of soft contact lenses, wherein the material is a substantially unpolymerized polymer comprising a crosslinkable group, and wherein a high energy is applied to the plurality of particles prior to the water cooperation step C On top of the formed lens blank: the polymer is thereby crosslinked to achieve a joint density. The method of making a soft contact lens in the range of items i to 4 of the patent range, wherein the system T is provided in the form of a thin plate. 9. A method of making a plurality of soft contact lenses according to the scope of the patent application, wherein the sheet is used as a wheeling medium or carrier for the plurality of formed lens blanks. 1 0 · A method for manufacturing a plurality of soft contact lenses according to any one of the first s β κ 祀 弟 弟 1 to 4 of the patent application scope, in the stage after the step ,, by using a ray The shot cutting device, Jiang Yiyi, completely removes the plurality of formed lens blanks from the sheet. 1 1. A method of manufacturing a plurality of soft contact lenses according to any one of items 1-4 to 4 according to the patent application, wherein the physical formation step B is performed by using any physical formation method. The physical formation method is selected from the group consisting of a heat forming method, a vacuum forming method, or a pressing method, or a hot molding 21 1344897 method, or a cold molding method, or a compression forming method group. in.旳·7· or a method of injection molding according to any one of the plurality of soft contact lenses according to any one of claims 1-4 to 4, wherein the physical Λ 乡 乡 B includes the following substeps : ~ Β.1 heating the material to a temperature which is close to the softening temperature of the material, thereby making the formation of the material possible, but the thermal shape b) is lower than the melting point of the material; and thereby maintaining the The physical integrity of the material B.2 is thermally formed by applying a physical force to the lens blank on the material. Forming the plurality 1 3 · A method of manufacturing a plurality of soft contact lenses according to the scope of claim 2, wherein the heat forming substep comprises compressing a material between: formations or platforms. The method of manufacturing a plurality of soft hidden mirrors according to any one of claims 1 to 4, wherein the physical forming step B comprises using a mold, and placing the material between the molds The molds are intended to be formed together to form the plurality of formed lens blanks. A method of manufacturing a plurality of soft contact lenses according to any one of claims 1 to 4, which is automated or semi-automated in a continuous or semi-continuous manner. 22 1344897 97. 7. r2 XI, schema: as the next page twenty three