Colored soft hydrophilic corneal contact lens and manufacturing method thereof

Abstract

The invention provides a colored soft hydrophilic corneal contact lens and a manufacturing method thereof, and belongs to the technical field of corneal contact lenses. The pigment layer is printed and dyed on the surface of the inner film layer material in a film printing and dyeing manner, so that the inner film layer can well prevent the pigment layer from being in direct contact with eyes. The inner film layer, the pigment layer and the lens layer are subjected to process treatment means of mould pressing, curing and turning, and finally the colored soft hydrophilic corneal contact lens is obtained. The stability of the contact lens is effectively improved by improving a film-covering printing and dyeing process and a multi-temperature-section heat treatment mode, so that the contact lens is not easy to dehydrate and can be kept wet for a long time. The long-chain polymer and the polymeric monomer are matched with each other, so that the inner film coating layer is softer and better fits eyes, and the use comfort of a user is improved.

Description

Technical Field

[0001] The invention relates to the technical field of corneal contact lenses, and in particular to a colored soft hydrophilic corneal contact lens and a manufacturing method thereof. Background Art

[0002] Contact lenses, or corneal contact lenses, are lenses worn on the cornea of ​​the eye to correct vision or protect the eyes. They include hard and soft lenses. Contact lenses not only greatly improve the appearance and convenience of patients with refractive errors such as myopia, hyperopia, and astigmatism, but also provide a wide field of vision and realistic vision. In addition, they also play a special role in controlling the development of myopia and astigmatism in adolescents and treating special eye diseases.

[0003] Contact lenses have now developed into colored ones, which are mostly used to beautify pupils, and are called colored contact lenses. Colored contact lenses can be divided into three types according to the position structure of the color layer: the first is that the color layer is coated on the non-optical area of ​​the inner surface of the contact lens material: the second is that the color layer is coated on the non-optical area of ​​the outer surface of the contact lens material. Both methods are to coat the color layer on the surface of the contact lens material, so that the color layer will directly contact the cornea or eyelid when worn, causing discomfort when worn, and the color layer will also cause more or less damage to the eyes: the third method is to place the color layer in the middle of the interlayer of the non-optical area of ​​the contact lens material. This approach overcomes the above two shortcomings and makes the user safer during wearing. However, the three-layer structure increases the thickness of the contact lens, which reduces the wearing comfort, and this preparation process is not easy to control the thickness of the lens. Due to the setting of the middle interlayer and the inner film layer, the lens has poor oxygen permeability and low water content, and the user is prone to fatigue after wearing for a long time.

[0004] Therefore, with respect to the above-mentioned prior art, how to obtain a colored soft hydrophilic corneal contact lens with simple process and increased wearing comfort and a manufacturing method thereof is a technical problem that needs to be solved at present. Summary of the invention

[0005] The purpose of the present invention is to provide a colored soft hydrophilic corneal contact lens and a manufacturing method thereof, so as to solve the technical problems of the existing colored contact lenses being too thick, having poor oxygen permeability and having low water content.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0007] The present invention provides a method for manufacturing a colored soft hydrophilic corneal contact lens, wherein the colored soft hydrophilic corneal contact lens comprises an inner coating layer, a pigment layer and a lens layer;

[0008] The production method comprises the following steps:

[0009] (1) mixing methacryloyloxy polydimethylsiloxane, methyl methacrylate, acrylamide, benzoyl peroxide and styrene to obtain a mixture 1;

[0010] (2) mixing ethylene glycol ethyl ether and butyl acetate to obtain mixture 2, and adding mixture 1 dropwise into mixture 2 to carry out polymerization reaction to obtain an inner coating layer material;

[0011] (3) placing the inner coating layer material in a convex mold, printing and dyeing pigments on the inner coating layer material using a printing and dyeing machine, and performing a color fixing treatment on the pigments to obtain a pigment layer;

[0012] (4) Methacryloxy polydimethylsiloxane, 2-ethoxyethyl methacrylate, polyethylene glycol and azobisisobutyronitrile are mixed to obtain a mixture 3, which is then injected into a molding machine, and the mixture 3 is injected into the blow-molded concave mold, and then the convex mold is pressed down into the concave mold for molding to obtain a lens layer;

[0013] (5) performing a segmented heat treatment on the molded mold to obtain a colored soft hydrophilic corneal contact lens semi-finished mold;

[0014] (6) subjecting the colored soft hydrophilic corneal contact lens semi-finished product mold to a turning process and a hydration process in sequence, and demolding the mold to obtain the colored soft hydrophilic corneal contact lens;

[0015] Alternatively, the molded mold can be directly placed in a constant temperature drying oven for curing, and a colored soft hydrophilic corneal contact lens can be obtained after demoulding.

[0016] Furthermore, the inner coating layer is obtained by polymerization of raw materials containing the following mass fractions:

[0017] 50-60 parts of methacryloxy polydimethylsiloxane;

[0018]

[0019] Furthermore, the lens layer is prepared from raw materials comprising the following mass fractions:

[0020]

[0021]

[0022] Furthermore, in the step (2), the polymerization reaction temperature is 110 to 130° C., and the polymerization reaction time is 20 to 50 minutes.

[0023] Furthermore, in step (3), the temperature of the color fixing treatment is 120-130° C., and the time of the color fixing treatment is 30-40 minutes.

[0024] Furthermore, in the step (4), the molding temperature is 100-110°C.

[0025] Furthermore, in step (4), the specific steps of the staged heat treatment are: first heating at 60-80°C for 20 min, then heating at 80-100°C for 20 min, then heating at 100-105°C for 20 min, and finally heating at 105-115°C for 50 min.

[0026] Furthermore, the dropping rate is 1 to 2 s / drop.

[0027] The invention also provides a colored soft hydrophilic corneal contact lens.

[0028] Beneficial effects of the present invention:

[0029] The manufacturing process of the present invention allows the pigment layer to be printed on the surface of the inner coating layer, and after heating and fixing, an ultra-thin pigment layer is formed, thereby reducing the overall thickness of the contact lens. The inner coating layer material of the present invention uses a long-chain polymer and a polymerized monomer to cooperate with each other, so that the inner coating layer has better flexibility, and the long-chain polymer contains siloxane, which can increase the overall oxygen permeability and water content of the contact lens, so that the wearer has a better wearing effect.

[0030] The present invention improves the stability of the contact lenses and reduces the dehydration of the contact lenses by performing segmented heat treatment on the semi-finished contact lenses through a process of staged temperature increase treatment, so that the contact lenses can be worn in a high temperature environment in summer without obvious dehydration and cracking, thereby improving the stability of the contact lenses. DETAILED DESCRIPTION

[0031] The present invention provides a method for manufacturing a colored soft hydrophilic corneal contact lens, wherein the colored soft hydrophilic corneal contact lens comprises an inner coating layer, a pigment layer and a lens layer;

[0032] The production method comprises the following steps:

[0033] (1) mixing methacryloyloxy polydimethylsiloxane, methyl methacrylate, acrylamide, benzoyl peroxide and styrene to obtain a mixture 1;

[0034] (2) mixing ethylene glycol ethyl ether and butyl acetate to obtain mixture 2, and adding mixture 1 dropwise into mixture 2 to carry out polymerization reaction to obtain an inner coating layer material;

[0035] (3) placing the inner coating layer material in a convex mold, printing and dyeing pigments on the inner coating layer material using a printing and dyeing machine, and performing a color fixing treatment on the pigments to obtain a pigment layer;

[0036] (4) Methacryloxy polydimethylsiloxane, 2-ethoxyethyl methacrylate, polyethylene glycol and azobisisobutyronitrile are mixed to obtain a mixture 3, which is then injected into a molding machine, and the mixture 3 is injected into the blow-molded concave mold, and then the convex mold is pressed down into the concave mold for molding to obtain a lens layer;

[0037] (5) performing a segmented heat treatment on the molded mold to obtain a colored soft hydrophilic corneal contact lens semi-finished mold;

[0038] (6) subjecting the colored soft hydrophilic corneal contact lens semi-finished product mold to a turning process and a hydration process in sequence, and demolding the mold to obtain the colored soft hydrophilic corneal contact lens;

[0039] Alternatively, the molded mold can be directly placed in a constant temperature drying oven for curing, and a colored soft hydrophilic corneal contact lens can be obtained after demoulding.

[0040] In the present invention, the inner coating layer is obtained by polymerization of raw materials containing the following mass fractions:

[0041] 50-60 parts of methacryloxy polydimethylsiloxane;

[0042] 10-15 parts of methyl methacrylate;

[0043] 1 to 10 parts of acrylamide;

[0044] 60-70 parts of ethylene glycol ethyl ether;

[0045] 5-15 parts of butyl acetate;

[0046] 1-10 parts of benzoyl peroxide;

[0047] 2 to 5 parts of styrene.

[0048] In the present invention, the content of the methacryloxy polydimethylsiloxane is preferably 52 to 58 parts by mass, more preferably 54 to 56 parts, and even more preferably 55 parts.

[0049] In the present invention, the content of methyl methacrylate is preferably 11 to 14 parts by mass, more preferably 12 to 13 parts, and more preferably 12.5 parts.

[0050] In the present invention, the content of acrylamide is preferably 2 to 8 parts by mass, more preferably 4 to 6 parts, and even more preferably 5 parts.

[0051] In the present invention, the content of the ethylene glycol ethyl ether is preferably 62 to 68 parts by mass, more preferably 64 to 66 parts, and even more preferably 65 parts.

[0052] In the present invention, the content of butyl acetate is preferably 6 to 12 parts by mass, more preferably 8 to 10 parts, and even more preferably 9 parts.

[0053] In the present invention, the content of the benzoyl peroxide is preferably 2 to 8 parts by mass, more preferably 4 to 6 parts, and more preferably 5 parts.

[0054] In the present invention, the content of styrene is preferably 2.5 to 4.5 parts by mass, more preferably 3 to 4 parts, and even more preferably 4.5 parts.

[0055] In the present invention, the lens layer is prepared from raw materials comprising the following mass fractions:

[0056] 80-90 parts of methacryloxy polydimethylsiloxane;

[0057] 1 to 5 parts of 2-ethoxyethyl methacrylate;

[0058] 5-15 parts of polyethylene glycol;

[0059] 0.5 to 2 parts of azobisisobutyronitrile.

[0060] In the present invention, the content of the methacryloxy polydimethylsiloxane is preferably 82 to 88 parts by mass, more preferably 84 to 86 parts, and even more preferably 85 parts.

[0061] In the present invention, the content of the 2-ethoxyethyl methacrylate is preferably 1.5 to 4.5 parts by mass, more preferably 2 to 4 parts, and even more preferably 2.5 to 3.5 parts.

[0062] In the present invention, the content of the polyethylene glycol is preferably 6 to 12 parts by mass, more preferably 8 to 10 parts, and even more preferably 9 parts.

[0063] In the present invention, the content of azobisisobutyronitrile is preferably 1 to 1.5 parts by mass, and more preferably 1.2 parts.

[0064] In the present invention, in step (2), the polymerization reaction temperature is 110-130°C, preferably 115-125°C, and more preferably 120°C; the polymerization reaction time is 20-50 min, preferably 30-40 min, and more preferably 35 min.

[0065] In the present invention, in step (3), the temperature of the color fixing treatment is 120-130° C., preferably 125° C.; the time of the color fixing treatment is 30-40 min, preferably 32-38 min, and more preferably 35 min.

[0066] In the present invention, in the step (4), the molding temperature is 100-110°C, preferably 102-108°C, and more preferably 105°C.

[0067] In the present invention, in the step (4), the specific steps of the segmented heat treatment are: first heating at 60-80°C for 20 min, then heating at 80-100°C for 20 min, then heating at 100-105°C for 20 min, and finally heating at 105-115°C for 50 min; preferably, first heating at 65-75°C for 20 min, then heating at 85-95°C for 20 min, then heating at 105°C for 20 min, and finally heating at 108-110°C for 50 min.

[0068] In the present invention, the dropping rate is 1 to 2 s / drop, preferably 2 s / drop.

[0069] The invention also provides a colored soft hydrophilic corneal contact lens.

[0070] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0071] Example 1

[0072] A method for manufacturing a colored soft hydrophilic corneal contact lens:

[0073] (1) weighing 55 parts of methacryloxy polydimethylsiloxane, 13 parts of methyl methacrylate, 10 parts of acrylamide, 2 parts of benzoyl peroxide and 2 parts of styrene, mixing and stirring the raw materials to obtain a mixture 1;

[0074] (2) Weighing 65 parts of ethylene glycol ethyl ether and 10 parts of butyl acetate, mixing and stirring to obtain a mixture 2, slowly dropping the mixture 1 into the mixture 1, heating at 110° C. while stirring to cause a polymerization reaction, reacting for 50 minutes, cooling to room temperature, and obtaining an inner coating layer material;

[0075] (3) placing the inner film layer material in a convex mold, and operating it using a two-color printing and dyeing machine. The inner film layer material is placed in the first oil cup of the two-color printing and dyeing machine, and the prepared pigment is placed in the second oil cup. The inner film layer material is first printed on the convex mold by the printing and dyeing machine to obtain an inner film layer, and then the pigment is printed on the inner film layer. The convex mold printed with the pigment is placed in an oven for color fixing treatment, the temperature is set to 120° C., and the color fixing time is 30 minutes to obtain a pigment layer;

[0076] (4) weighing 82 parts of methacryloyloxy polydimethylsiloxane, 3 parts of 2-ethoxyethyl methacrylate, 15 parts of polyethylene glycol and 2 parts of azobisisobutyronitrile, stirring and mixing to obtain a mixture 3; injecting the mixture 3 into a steel tank of a molding machine, injecting the mixture 3 into the blow-molded concave mold, and then pressing the convex mold down into the concave mold for molding at 100° C. to obtain a lens layer;

[0077] (5) performing a segmented heat treatment on the mold after forming, and the segmented temperatures are shown in Table 1 below. After the heat treatment is completed, a semi-finished mold of a colored soft hydrophilic corneal contact lens is obtained;

[0078] (6) The colored soft hydrophilic corneal contact lens semi-finished product mold is turned by a lathe to obtain the light, and then the surface is ground to obtain a sheet, and then the sheet is hydrated to obtain a colored soft hydrophilic corneal contact lens.

[0079] Table 1 Process parameters of staged heat treatment

[0080]

[0081]

[0082] Example 2

[0083] The same as Example 1, except that the inner coating layer material comprises: 60 parts of methacryloxy polydimethylsiloxane, 10 parts of methyl methacrylate, 5 parts of acrylamide, 5 parts of benzoyl peroxide, 2 parts of styrene, 70 parts of ethylene glycol ethyl ether and 5 parts of butyl acetate.

[0084] The lens layer material comprises: 80 parts of methacryloxy polydimethylsiloxane, 1 part of 2-ethoxyethyl methacrylate, 10 parts of polyethylene glycol and 1 part of azobisisobutyronitrile.

[0085] Example 3

[0086] The same as Example 1, except that the inner coating layer material comprises: 50 parts of methacryloxy polydimethylsiloxane, 12 parts of methyl methacrylate, 10 parts of acrylamide, 10 parts of benzoyl peroxide, 2 parts of styrene, 60 parts of ethylene glycol ethyl ether and 15 parts of butyl acetate.

[0087] The lens layer material comprises: 90 parts of methacryloxy polydimethylsiloxane, 3 parts of 2-ethoxyethyl methacrylate, 15 parts of polyethylene glycol and 2 parts of azobisisobutyronitrile.

[0088] In order to verify the advantages of the staged heat treatment process of the present invention, the following comparative examples were made for comparison:

[0089] Comparative Example 1

[0090] The same as Example 1, except that the staged heat treatment process is different, as shown in Table 2 below:

[0091] Table 2 Staged heat treatment process

[0092] project first Second time The third time Fourth Temperature(℃) 65 80 110 115 Time (min) 20 20 20 50

[0093] Comparative Example 2

[0094] The same as Example 1, except that the staged heat treatment process is different, as shown in Table 2 below:

[0095] Table 3 Staged heat treatment process

[0096]

[0097]

[0098] In order to verify the advantages of using the raw materials of the present invention, the following comparative examples were compared:

[0099] Comparative Example 3

[0100] The same as Example 1, except that the inner coating layer material comprises: 50 parts of 2-hydroxyethyl methacrylate, 12 parts of methyl methacrylate, 10 parts of methacrylic acid, 10 parts of benzoyl peroxide, 2 parts of styrene, 60 parts of ethylene glycol ethyl ether and 15 parts of butyl acetate.

[0101] Comparative Example 4

[0102] Same as Example 1, except that the lens layer material comprises: 90 parts of 2-hydroxyethyl methacrylate, 3 parts of 2-ethoxyethyl methacrylate, 15 parts of polyethylene glycol and 2 parts of azobisisobutyronitrile.

[0103] The various properties of the colored soft hydrophilic corneal contact lenses obtained in the above examples and comparative examples were tested respectively, and the results are shown in Table 4 below:

[0104] Table 4 Comparison of lens center thickness under different heat treatment processes

[0105]

[0106] The comparison of oxygen permeability and flexibility of lenses under different raw material ratios is shown in Table 5 below;

[0107] Table 5 Comparison of lens performance under different raw material ratios

[0108]

[0109]

[0110] The oxygen permeability test: use an oxygen permeability tester to measure the change of oxygen content in the permeation cavity over time after oxygen permeates through the membrane, calculate the slope k of the curve of oxygen content change over time, and at the same time determine the permeation cavity volume V, contact lens film thickness t and contact lens film contact air part membrane area S, and calculate the oxygen permeability according to the following formula DK / t=Vk / SΔP.

[0111] The dehydration rate test was performed on the lenses of Example 1 and Comparative Examples 1 and 2. The results are shown in Table 6 below:

[0112] Table 6 Dehydration rate results

[0113]

[0114] It can be seen from the above embodiments that the present invention provides a colored soft hydrophilic corneal contact lens and a method for making the same. The above experiments have verified that the colored soft hydrophilic corneal contact lens obtained by the present invention has significantly improved lens thickness under specific processing conditions, and the error of the center thickness of the produced lens does not exceed ±0.002mm, which meets the wearing comfort. The inner coating layer obtained by the specific inner coating material of the present invention not only has high oxygen permeability, but also has good softness. After tensile test, it meets the national standards and will not have obvious cracks, meeting the needs of users who wear contact lenses for a long time; at the same time, the corneal contact lens obtained by the present invention has good stability, and the dehydration rate within 30 minutes is only 0.0001g / min.

[0115] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for manufacturing a colored soft hydrophilic corneal contact lens, characterized in that: The colored soft hydrophilic corneal contact lens comprises an inner coating layer, a pigment layer and a lens layer; The production method comprises the following steps: (1) mixing methacryloyloxy polydimethylsiloxane, methyl methacrylate, acrylamide, benzoyl peroxide and styrene to obtain a mixture 1; (2) mixing ethylene glycol ethyl ether and butyl acetate to obtain mixture 2, and adding mixture 1 dropwise into mixture 2 to carry out polymerization reaction to obtain an inner coating layer material; (3) placing the inner coating layer material in a convex mold, printing and dyeing pigments on the inner coating layer material using a printing and dyeing machine, and performing a color fixing treatment on the pigments to obtain a pigment layer; (4) Methacryloxy polydimethylsiloxane, 2-ethoxyethyl methacrylate, polyethylene glycol and azobisisobutyronitrile are mixed to obtain a mixture 3, which is then injected into a molding machine, and the mixture 3 is injected into the blow-molded concave mold, and then the convex mold is pressed down into the concave mold for molding to obtain a lens layer; (5) performing a segmented heat treatment on the molded mold to obtain a colored soft hydrophilic corneal contact lens semi-finished mold; (6) subjecting the colored soft hydrophilic corneal contact lens semi-finished product mold to a turning process and a hydration process in sequence, and demolding the mold to obtain the colored soft hydrophilic corneal contact lens; Alternatively, the molded mold can be directly placed in a constant temperature drying oven for curing, and a colored soft hydrophilic corneal contact lens can be obtained after demoulding.

2. The method for manufacturing a colored soft hydrophilic corneal contact lens according to claim 1, characterized in that: The inner coating layer is obtained by polymerization of raw materials including the following mass parts:

3. The method for manufacturing a colored soft hydrophilic corneal contact lens according to claim 1 or 2, characterized in that: The lens layer is prepared from raw materials comprising the following mass fractions:

4. The method for manufacturing a colored soft hydrophilic corneal contact lens according to claim 3, characterized in that: In the step (2), the polymerization reaction temperature is 110 to 130° C., and the polymerization reaction time is 20 to 50 minutes.

5. The method for manufacturing a colored soft hydrophilic corneal contact lens according to claim 1, 2 or 4, characterized in that: In the step (3), the temperature of the color fixing treatment is 120-130° C., and the time of the color fixing treatment is 30-40 minutes.

6. The method for manufacturing a colored soft hydrophilic corneal contact lens according to claim 5, characterized in that: In the step (4), the molding temperature is 100-110°C.

7. The method for manufacturing a colored soft hydrophilic corneal contact lens according to claim 1 or 6, characterized in that: In step (4), the specific steps of the staged heat treatment are: first heating at 60-80°C for 20 min, then heating at 80-100°C for 20 min, then heating at 100-105°C for 20 min, and finally heating at 105-115°C for 50 min.

8. The method for manufacturing a colored soft hydrophilic corneal contact lens according to claim 7, characterized in that: The dropping rate is 1-2 s / drop.

9. A colored soft hydrophilic corneal contact lens prepared by the method according to any one of claims 1 to 8.

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