Demoulding process suitable for mould pressing production mode of soft contact lenses

Abstract

The invention relates to a demolding process suitable for a mold pressing production mode of soft contact lenses. The demolding process comprises the following steps: S1, providing a male mold and a female mold; s2, an arc-shaped light shield is fixed to the preset positions of the male mold and the female mold, optical mold surfaces of the male mold and the female mold are divided, and a lens body area and an outer circumference excess material area are isolated; s3, the irradiation angle of the UV light source is adjusted through an optical positioning system, so that part of light is focused on the shielding area of the arc-shaped light shield, and it is ensured that the UV light only acts on the outer circumferential excess material area at the moment; s4, adjusting the output power of the UV light source to a pre-installation condition, carrying out limited area irradiation modification treatment on the optical mold surfaces of the male mold and the female mold, and controlling the adhesive force difference between the lens body area and the outer circumference excess material area; s5, after glue injection is conducted on the female mold monomers, the female mold monomers and the male mold are assembled, and photocuring or thermocuring treatment is conducted; s6, after curing is completed, the male mold and the female mold are separated, and the preliminarily-formed contact lenses are obtained.

Description

Technical Field

[0001] This application relates to the technical field of soft contact lens production, and particularly to a demolding process applicable to the molding production method of soft contact lenses. Background Art

[0002] As a medical device that directly contacts the eyeball, the production process of soft contact lenses has extremely high requirements for precision, efficiency, and product quality. The traditional production of soft contact lenses usually adopts a molding process, where a mold cavity is formed by the cooperation of a male mold and a female mold, and the lens is injection-molded. However, during the demolding process, the adhesion force between the lens and the mold is relatively large, especially the adhesion problem between the outer circumferential surplus material area and the mold, which easily leads to difficult demolding, lens damage or deformation, seriously affecting production efficiency and product yield. In addition, the mechanical or chemical action on the lens body area during the demolding process may damage its optical surface properties, resulting in problems such as uneven refractive index distribution and decreased surface finish, affecting the wearing comfort and visual clarity of the final product.

[0003] Chinese Patent CN110843179B discloses an injection molding device for the mirror surface of environmentally friendly injection molded spectacle lenses. It breaks through the structural form of the traditional injection molded spectacle lens mirror surface processing device, keeps the second moving pressure plate in contact with the second fixed plate, and the first horizontal driving device drives the first moving pressure plate to squeeze each layer mold towards the second fixed plate; when each layer mold is tightened, each demolding plate completely enters the mold groove and fits tightly with the bottom of the mold groove, each connecting ear completely enters the first accommodating groove, and each compression spring completely enters the second accommodating groove, the controller controls each driving device to drive each side mold to move towards the right side of the forming mold; preheat the injection molding device; and sequentially perform feeding, cooling, and demolding.

[0004] Although in the above solution, by setting a multi-layer mold structure, wherein the second moving pressure plate remains in contact with the second fixed plate, and the first horizontal driving device drives the first moving pressure plate to squeeze each layer mold towards the second fixed plate, so that during the demolding process, each layer mold can be evenly and tightly tightened, reducing the adhesion force between the lens and the mold; however, the adhesion problem between the outer circumferential surplus material area and the mold in the male and female molds is still not solved. Therefore, during the actual demolding process, the stress transfer in the working area may cause an unexpected mechanical coupling effect between the lens body and the surplus material, resulting in the lens and the surplus material being synchronously separated from the mold surface with a non-ideal cross-section (whether the lens drives the surplus material or the surplus material drives the lens), and finally forming a defective product with an abnormal connection cross-section.

[0005] Therefore, we hereby propose a demolding process applicable to the molding production method of soft contact lenses. Summary of the Invention

[0006] The main purpose of the present application is to provide a demolding process applicable to the molding production method of soft contact lenses, aiming to solve the problems of difficult demolding, reduced product yield, and impaired optical performance caused by excessive adhesion force between the outer circumferential waste material area of the lens and the mold in the prior art.

[0007] To achieve the above object, the present application provides a demolding process applicable to the molding production method of soft contact lenses, including the following steps: S1. Provide a male mold and a female mold; S2. Fix an arc-shaped light shield at a predetermined position of the male mold and the female mold, divide the optical mold surfaces of the male mold and the female mold by region, and isolate the lens body region and the outer circumferential waste material region; the optical mold surface is specifically: the region in the male mold and the female mold for forming the optical surface of the contact lens; S3. Adjust the irradiation angle of the UV light source through an optical positioning system so that part of its light rays are focused on the shielded area of the arc-shaped light shield, ensuring that the UV light only acts on the outer circumferential waste material area at this time; S4. Adjust the output power of the UV light source to the preset operating conditions, perform a limited-area irradiation modification treatment on the optical mold surfaces of the male mold and the female mold, and control the adhesion force difference between the lens body region and the outer circumferential waste material region; S5. After injecting glue into the female mold monomer, close the mold with the male mold and perform light curing or heat curing treatment; S6. After the curing is completed, separate the male mold and the female mold to obtain a preliminarily formed contact lens; S7. Perform dry demolding or wet demolding on the lens to separate the lens from the waste material.

[0008] Preferably, in step S3, the optical positioning system collects the cavity images of the male mold and the female mold through a CCD camera, identifies the edge of the optical mold surface, and adjusts the incident angle of the UV light source to 5° - 15° so that the light rays are refracted by the arc-shaped light shield and focused on the outer circumferential waste material area.

[0009] Preferably, the arc-shaped light shield includes a base layer, a liquid crystal layer, and an electrode layer. The base layer is attached to the lens body regions of the male mold and the female mold. The liquid crystal layer is coated on the surface of the base layer, and the electrode layer is arranged on the side of the liquid crystal layer away from the base layer. The electrode layer is used to receive an external electrical signal to regulate the light transmission state of the liquid crystal layer, and accurately shield the outer circumferential waste material area by controlling the molecular arrangement of the liquid crystal layer.

[0010] Preferably, the base layer is made of a flexible polymer material, and its curvature matches the optical mold surfaces of the male mold and the female mold, with a thickness of 50-200 μm; the liquid crystal layer is made of an electrically controlled birefringent liquid crystal material, and the difference in refractive index between the non-powered state and the base layer is less than 0.05, which is used to form a grating structure through molecular orientation changes after power-on to block light in a specific wavelength band; the electrode layer is a transparent conductive oxide layer, and its sheet resistance value ≤ 50 Ω.

[0011] Preferably, a gradient light-transmitting structure is provided at the shielding edge of the arc-shaped light-shielding cover, and its light transmittance increases linearly from 5% to 30% outward along the shielding area to achieve a smooth transition of the UV modification area.

[0012] Preferably, in step S4, the preset application conditions include that the wavelength of the UV light source is 365 nm, the output power is 100-500 W, and the irradiation time is 10-60 seconds.

[0013] Preferably, in step S4, when it is necessary to perform surface modification on the outer circumferential remaining material area, the liquid crystal layer of the arc-shaped light-shielding cover is in a scattered state, shielding the lens body area, and the outer circumferential remaining material area is irradiated with high-intensity UV light, with the power controlled within the range of 300-500 W and the irradiation time of 30-60 seconds to form a hydrophobic surface with a surface contact angle of 80°-120°.

[0014] Preferably, in step S4, when it is necessary to perform surface modification on the lens body area, the liquid crystal layer of the arc-shaped light-shielding cover is switched to a transparent state to allow UV light to pass through, and the lens body area is irradiated with low-intensity UV light, with the power controlled within the range of 100-300 W and the irradiation time of 10-30 seconds to form a hydrophilic surface with a surface contact angle of 50°-70°.

[0015] Preferably, the photocuring treatment uses ultraviolet light with a wavelength of 365 nm and a curing time of 10-30 minutes; the temperature of the thermal curing treatment is 50-80 °C and the curing time is 1-3 hours; the temperature of the thermal curing treatment is 50-80 °C and the curing time is 1-3 hours.

[0016] Preferably, the dry demolding adopts a mechanical peeling method; the wet demolding is assisted by spraying a wetting agent on the remaining material area to reduce the adhesion force, and the wetting agent is physiological saline or boric acid buffer solution.

[0017] The beneficial effects of the technical solution of the present invention are as follows: By adjusting the output power of the UV light source and combining it with the shielding effect of the arc-shaped light shield, limited-area irradiation and modification treatment are carried out on the optical mold surfaces of the male mold and the female mold, precisely controlling the adhesion force difference between the lens body area and the outer circumferential surplus material area. This enables the lens body to maintain a relatively stable attachment state during the subsequent demolding process, while the outer circumferential surplus material area is more easily separated from the lens due to the reduced adhesion force, greatly improving the demolding success rate and the integrity of the lens. At the same time, since the UV light only acts on the outer circumferential surplus material area, over-irradiation and potential impacts on the lens body area are avoided. This ensures that the optical mold surface of the contact lens does not undergo changes in optical properties, such as uneven refractive index distribution and decreased surface finish, due to improper light treatment during the molding process, thereby guaranteeing that the finally produced contact lens has excellent optical properties and meets the requirements of users for visual clarity and comfort.

[0018] The optical positioning system is used to determine the precise position where the UV light source needs to irradiate, and the incident angle of the UV light source is adjusted so that its light can precisely act on the predetermined area, that is, the outer circumferential surplus material area, after being refracted by the arc-shaped light shield, without affecting the lens body area. At the same time, the incident angle of the UV light source is adjusted to the range of 5° - 15°, which can not only ensure that the light has sufficient energy to penetrate the light shield and focus on the target area, but also avoid energy waste or potential damage to the mold caused by overly concentrated light.

[0019] For the outer circumferential surplus material area, high-intensity UV irradiation is used to form a hydrophobic surface with a contact angle of 80° - 120° on its surface, thereby effectively reducing the adhesion force between the surplus material and the mold. During the subsequent demolding process, the outer circumferential surplus material is more easily detached from the mold, reducing the external force required for demolding and the risk of damage to the lens during demolding, while also improving production efficiency. For the lens body area, low-intensity UV irradiation is used to form a hydrophilic surface with a contact angle of 50° - 70°, improving the wettability and adhesion of the lens surface, enhancing the bonding force between the coating or film and the lens surface, and improving product quality. Description of the Drawings

[0020] Figure 1 It is a schematic diagram of the production process flow of soft contact lenses in the prior art; Figure 2 It is a schematic structural diagram of the modification treatment device for the optical mold surface of the female mold in an embodiment of the present application; Figure 3 It is a schematic structural diagram of the modification treatment device for the optical mold surface of the male mold in an embodiment of the present application; Figure 4 It is a disassembled diagram of the wavelength spectrum of the UV light source in an embodiment of the present application. Detailed Embodiments

[0021] Embodiments of the present application will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary and are intended to explain the present application, and should not be construed as limiting the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.

[0022] In addition, if the description in the present application involves "first", "second", etc., it is only for descriptive purposes (such as for distinguishing the same or similar elements), and should not be construed as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement them. When the combination of the technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present application.

[0023] Referring to Figures 2 - 3 , the present invention provides a demolding process applicable to the molding production method of soft contact lenses, including the following steps: S1. Provide a male mold and a female mold. The female mold is used for injection molding a contact lens lens; the male mold is used to cooperate with the female mold to form a mold cavity to define the shape of the contact lens lens. S2. Fix an arc-shaped light shield at a predetermined position of the male mold and the female mold, and divide the optical mold surfaces of the male mold and the female mold to isolate the lens body area and the outer circumferential surplus material area; the optical mold surface specifically refers to: the area of the male mold and the female mold used for molding the optical surface of the contact lens lens. S3. Adjust the irradiation angle of the UV light source through an optical positioning system so that part of its light is focused on the shielded area of the arc-shaped light shield to ensure that the UV light only acts on the outer circumferential surplus material area at this time. S4. Adjust the output power of the UV light source to the preset operating conditions, and perform a limited-area irradiation modification treatment on the optical mold surfaces of the male mold and the female mold to control the adhesion force difference between the lens body area and the outer circumferential surplus material area. S5. After injecting glue into the female mold monomer, close the mold with the male mold and perform photocuring or thermosetting treatment. S6. After curing is completed, separate the male mold and the female mold to obtain a preliminarily formed contact lens lens. S7. Perform dry demolding or wet demolding on the lens to separate the lens from the surplus material.

[0024] In this embodiment, in step S4, by adjusting the output power of the UV light source and combining with the shielding effect of the arc-shaped light shield, the optical mold surfaces of the male mold and the female mold are subjected to limited-area irradiation and modification treatment, accurately controlling the adhesion force difference between the lens body area and the outer circumferential remaining material area. So that during the subsequent demolding process, the lens body can maintain a relatively stable attachment state, while the outer circumferential remaining material area is easier to separate from the lens due to the reduction of the adhesion force, greatly improving the demolding success rate and the integrity of the lens. At the same time, since the UV light only acts on the outer circumferential remaining material area, it avoids over-irradiation and potential effects on the lens body area. Ensure that the optical mold surface of the contact lens lens will not cause changes in optical properties, such as uneven refractive index distribution, surface finish degradation, etc. during the molding process due to improper light treatment, thus ensuring that the finally produced contact lens has excellent optical properties and meets the requirements of users for visual clarity and comfort.

[0025] Furthermore, Figure 1 In the existing production process of soft contact lenses, the plasma or corona treatment method is used to change the dyne value of the optical mold surfaces of the male and female molds, so that the dyne value of the area treated by plasma or corona in the optical mold surfaces of the male and female molds increases, and a significant difference is formed with the dyne value of the area not treated by plasma or corona, thereby controlling the adhesion force difference between the lens body area and the outer circumferential remaining material area and realizing the control of the contact lens demolding process.

[0026] However, there are some inherent defects in the existing plasma or corona treatment methods. For example, it is difficult to precisely control the uniformity of plasma or corona treatment, which easily leads to uneven distribution of the dyne value in the treated area of the optical mold surfaces of the male and female molds, affecting the adhesion force difference between the lens body area and the outer circumferential remaining material area, making the demolding process unstable, and it is difficult to guarantee the integrity and optical properties of the lens.

[0027] In contrast, the limited-area irradiation and modification treatment method of adjusting the output power of the UV light source and combining with the shielding effect of the arc-shaped light shield in step S4 of this solution has significant advantages. By accurately adjusting the irradiation angle of the UV light source through the optical positioning system, the light is focused on the shielding area of the arc-shaped light shield, ensuring that the UV light only acts on the outer circumferential remaining material area, and can achieve precise positioning and area control of the optical mold surfaces of the male and female molds.

[0028] In summary, the processing method of this solution can not only effectively control the adhesion force difference between the lens body area and the outer circumferential waste material area, improve the demolding success rate and lens integrity, but also avoid adverse effects on the optical performance of the lens body area, ensuring the excellent optical performance of the contact lens. At the same time, the requirements for equipment and process environment are relatively low, making it easy to operate and control. The output power of the UV light source can be precisely adjusted according to preset conditions, and the arc-shaped light shield can maintain a stable shielding effect after its position is fixed, making the entire processing process have high stability and repeatability.

[0029] In one of the embodiments, in step S3, the optical positioning system collects cavity images of the male mold and the female mold through a CCD camera, identifies the edge of the optical mold surface, and adjusts the incident angle of the UV light source to 5° - 15°, so that the light is refracted by the arc-shaped light shield and focused on the outer circumferential waste material area.

[0030] In this embodiment, the optical positioning system determines the precise position where the UV light source needs to irradiate and adjusts the incident angle of the UV light source so that its light can accurately act on the predetermined area, that is, the outer circumferential waste material area, after being refracted by the arc-shaped light shield, without affecting the lens body area. At the same time, the incident angle of the UV light source is adjusted to the range of 5° - 15°, which can not only ensure that the light has enough energy to penetrate the light shield and focus on the target area, but also avoid energy waste or potential damage to the mold caused by overly concentrated light.

[0031] In one of the embodiments, the arc-shaped light shield includes a base layer, a liquid crystal layer, and an electrode layer. The base layer is attached to the lens body areas of the male mold and the female mold. The liquid crystal layer is coated on the surface of the base layer, and the electrode layer is disposed on the side of the liquid crystal layer away from the base layer. The electrode layer is used to receive an external electrical signal to regulate the light transmission state of the liquid crystal layer, and precise shielding of the lens body area is achieved by controlling the molecular arrangement of the liquid crystal layer.

[0032] Furthermore, the base layer is made of a flexible polymer material, and its curvature matches the optical mold surfaces of the male mold and the female mold, with a thickness of 50 - 200 μm. The liquid crystal layer is made of an electro-optically birefringent liquid crystal material, and its refractive index difference from that of the base layer in the non-powered state is less than 0.05, and it is used to form a grating structure through molecular orientation change after being powered on to block specific wavelength light. The electrode layer is a transparent conductive oxide layer, and its sheet resistance value ≤ 50 Ω.

[0033] In this embodiment, the liquid crystal layer uses an electro-controlled birefringence liquid crystal material, and the refractive index difference between the non-powered state and the refractive index of the base layer is limited to 0.05. On the one hand, when not powered, light can pass through the base layer and the liquid crystal layer more evenly, without causing obvious occlusion or influence on the lens body area. On the other hand, when receiving an external electrical signal, the electrode layer can quickly respond and regulate the arrangement of liquid crystal layer molecules to form a grating structure, and precisely block light of a specific wavelength band through the formed grating structure, realizing precise shielding of the lens body area.

[0034] At the same time, the electrode layer uses a transparent conductive oxide material, such as indium tin oxide (ITO). Its low-resistance characteristic ensures that the electrical signal can be efficiently conducted to the liquid crystal layer to achieve a fast and stable electro-controlled response; while the base layer is made of a flexible polymer material, and its curvature matches the optical mold surface of the male mold and the female mold. The thickness of 50 - 200μm enables the arc-shaped light-shielding cover to closely fit the lens body area of the mold, not only ensuring that there will be no light leakage or light scattering problems during the shielding process, but also effectively avoiding the stress concentration phenomenon caused by the non-fitting of the light-shielding cover and the mold surface, thereby protecting the optical mold surface of the mold from damage.

[0035] In one of the embodiments, a gradient light-transmitting structure is provided at the shielding edge of the arc-shaped light-shielding cover, and its light transmittance increases linearly by 5% - 30% outward along the shielding area to achieve a smooth transition of the UV modification area.

[0036] In this embodiment, the light transmittance of the gradient light-transmitting structure gradually increases outward along the shielding area, so that the intensity of the UV light presents a smooth transition in the shielding edge area, avoiding the stress concentration phenomenon caused by sudden light changes in the traditional shielding method. At the same time, it effectively suppresses the scattering and refraction of light at the shielding edge, making the boundary of the modified area clearer and smoother, avoiding abnormal lens edge performance caused by the "edge effect", making the adhesion force difference between the lens body area and the outer circumferential remaining material area more stable, improving the controllability of the demolding process, reducing the risk of demolding failure, and ensuring that the lens will not be torn or deformed due to uneven adhesion force during the demolding process.

[0037] See Figure 4 , in one of the embodiments, in step S4, the preset application conditions include that the wavelength of the UV light source is 365nm, the output power is 100 - 500W, and the irradiation time is 10 - 60 seconds.

[0038] Specifically, in step S4, when surface modification treatment is required for the outer circumferential surplus material region, the liquid crystal layer of the arc-shaped light shield is in a scattering state to shield the lens body region, and high-intensity UV irradiation is applied to the outer circumferential surplus material region with the power controlled within the range of 300 - 500W and the irradiation time of 30 - 60 seconds to form a hydrophobic surface with a surface contact angle of 80° - 120°. When surface modification treatment is required for the lens body region, the liquid crystal layer of the arc-shaped light shield switches to a transparent state to allow UV light to pass through, and low-intensity UV irradiation is applied to the lens body region with the power controlled within the range of 100 - 300W and the irradiation time of 10 - 30 seconds to form a hydrophilic surface with a surface contact angle of 50° - 70°.

[0039] In this embodiment, on the one hand, for the outer circumferential surplus material region, high-intensity UV irradiation is used to form a hydrophobic surface with a contact angle of 80° - 120° on its surface, thereby effectively reducing the adhesion force between the surplus material and the mold. During the subsequent demolding process, the outer circumferential surplus material is more likely to be detached from the mold, reducing the external force required for demolding, lowering the risk of damage to the lens during demolding, and improving production efficiency at the same time. On the other hand, for the lens body region, low-intensity UV irradiation is used to form a hydrophilic surface with a contact angle of 50° - 70°, improving the wettability and adhesion of the lens surface, enhancing the bonding force between the coating or film and the lens surface, and improving product quality.

[0040] Furthermore, this control method based on the state switching of the liquid crystal layer of the arc-shaped light shield and different UV irradiation intensities and times can directly enter this surface modification treatment link when the basic shaping of the lens is completed during the lens production process without additional complex equipment or process adjustment, simplifying the production process, reducing production costs and production cycles. At the same time, since this method can effectively improve demolding efficiency and product quality, it can also reduce the lens rejection rate caused by demolding problems, further enhancing the overall production efficiency.

[0041] In one of the embodiments, the photocuring treatment uses ultraviolet light with a wavelength of 365nm and a curing time of 10 - 30 minutes; the temperature of the thermal curing treatment is 50 - 80°C and the curing time is 1 - 3 hours; the temperature of the thermal curing treatment is 50 - 80°C and the curing time is 1 - 3 hours.

[0042] In one of the embodiments, the dry demolding adopts a mechanical peeling method; the wet demolding is assisted by spraying a wetting agent on the surplus material region to reduce the adhesion force, and the wetting agent is physiological saline or boric acid buffer solution.

[0043] It should be noted that in this text, the term "including", "comprising" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, apparatus, article or demolding process applicable to the molding production method of soft contact lenses including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or further includes elements inherent to such process, apparatus, article or demolding process applicable to the molding production method of soft contact lenses. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of additional identical elements in the process, apparatus, article or demolding process applicable to the molding production method of soft contact lenses that includes such element.

[0044] The above are only the preferred embodiments of the present application, and do not limit the patent scope of the present application accordingly. Any equivalent structural or equivalent process transformation made by using the content of the specification and drawings of the present application, or directly or indirectly applied in other related technical fields, shall equally be included in the patent protection scope of the present application.

Claims

1. A demolding process applicable to the molding production method of soft contact lenses, characterized in that, It includes the following steps: S1. Provide a male mold and a female mold; S2. Fix the arc-shaped light shield at the predetermined positions of the male mold and the female mold, divide the optical mold surfaces of the male mold and the female mold regionally, and isolate the lens body region and the outer circumferential surplus material region; the specific optical mold surface is: the region in the male mold and the female mold for forming the optical surface of the contact lens; S3. Adjust the irradiation angle of the UV light source through the optical positioning system so that part of its light rays are focused on the shielding region of the arc-shaped light shield to ensure that the UV light only acts on the outer circumferential surplus material region at this time; S4. Adjust the output power of the UV light source to the preset application conditions, perform limited-area irradiation and modification treatment on the optical mold surfaces of the male mold and the female mold, and control the adhesion force difference between the lens body region and the outer circumferential surplus material region; S5. After injecting glue into the female mold monomer, close the mold with the male mold and perform light curing or heat curing treatment; S6. After curing is completed, separate the male mold and the female mold to obtain a preliminarily formed contact lens; S7. Perform dry demolding or wet demolding on the lens to separate the lens from the surplus material.

2. The demoulding process applicable to the mould pressing production method of soft contact lenses according to claim 1, characterized in that In step S3, the optical positioning system collects the mold cavity images of the male mold and the female mold through a CCD camera, identifies the edge of the optical mold surface, and adjusts the incident angle of the UV light source to 5°-15° so that the light rays are refracted by the arc-shaped light shield and focused on the outer circumferential surplus material region.

3. A demolding process applicable to the molding production method of soft contact lenses according to claim 1, characterized in that, The arc-shaped light shield includes a base layer, a liquid crystal layer, and an electrode layer. The base layer is attached to the lens body regions of the male mold and the female mold. The liquid crystal layer is coated on the surface of the base layer, and the electrode layer is arranged on the side of the liquid crystal layer away from the base layer. The electrode layer is used to receive an external electrical signal to regulate the light transmission state of the liquid crystal layer, and precisely shield the outer circumferential surplus material region by controlling the molecular arrangement of the liquid crystal layer.

4. A demolding process applicable to the molding production method of soft contact lenses according to claim 3, characterized in that, The base layer is made of a flexible polymer material, its curvature matches the optical mold surfaces of the male mold and the female mold, and its thickness is 50-200 μm; the liquid crystal layer is made of an electro-controlled birefringence type liquid crystal material, and its refractive index difference from that of the base layer in the non-powered state is less than 0.05, and it is used to form a grating structure through molecular orientation change after being powered on to block light of a specific wavelength band; the electrode layer is a transparent conductive oxide layer, and its sheet resistance value ≤ 50 Ω.

5. A demolding process applicable to the molding production method of soft contact lenses according to claim 4, characterized in that, The shielding edge of the arc-shaped light shield is provided with a gradient light transmission structure, and its light transmission rate increases linearly by 5%-30% outward along the shielding region to achieve a smooth transition of the UV modification region.

6. A demolding process applicable to the molding production method of soft contact lenses according to claim 5, characterized in that The preset application conditions in step S4 include that the wavelength of the UV light source is 365 nm, the output power is 100-500 W, and the irradiation time is 10-60 seconds.

7. A demolding process applicable to the molding production method of soft contact lenses according to claim 6, characterized in that, In step S4, when it is necessary to perform modification treatment on the surface of the outer circumferential surplus material region, the liquid crystal layer of the arc-shaped light shield is in a scattering state, shielding the lens body region, and performing high-intensity UV irradiation on the outer circumferential surplus material region, with the power controlled within the range of 300-500 W and the irradiation time of 30-60 seconds to form a hydrophobic surface with a surface contact angle of 80°-120°.

8. A demolding process applicable to the molding production method of soft contact lenses according to claim 7, characterized in that, In step S4, when the surface of the lens body region needs to be modified, the liquid crystal layer of the arc-shaped light-shielding cover is switched to a transparent state to allow UV light to pass through. The lens body region is irradiated with low-intensity UV light with a power controlled within the range of 100-300 W and an irradiation time of 10-30 seconds to form a hydrophilic surface with a surface contact angle of 50°-70°.

9. A demoulding process applicable to the mould pressing production method of soft contact lenses according to claim 1, characterized in that The photocuring treatment uses ultraviolet light with a wavelength of 365 nm and a curing time of 10-30 minutes; the temperature of the thermal curing treatment is 50-80°C and the curing time is 1-3 hours; the temperature of the thermal curing treatment is 50-80°C and the curing time is 1-3 hours.

10. A demolding process applicable to the molding production method of soft contact lenses according to claim 1, characterized in that The dry demolding is carried out by mechanical peeling; the wet demolding is assisted by spraying a wetting agent on the surplus material region to reduce the adhesion force, and the wetting agent is physiological saline or boric acid buffer solution.

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