TW202021790A - Injection molding process for dual-material soft contact lenses including preparing materials, casting mold and forming, curing and shaping, and post-demoulding processing - Google Patents

Abstract

The present invention provides an injection molding process for dual-material soft contact lenses, and the method includes the following steps: preparing materials, casting mold and forming, curing and shaping, and post-demoulding processing. When the preparation is conducted in this way, a finished product having a first material in the center area and a second material in the outer ring area can be obtained. As a result, the purpose of combining different materials in the center area and in the outer area and being perfectly connected without mixing can be achieved.

Description

Two-material soft contact lens injection molding process

The present invention is a two-material soft contact lens injection molding process, which specifically refers to the technology applied in the contact lens field. This method is used to produce two-material contact lenses of different materials or colors in the inner and outer regions, and use them as contact lenses.

After the German scientist Adolf Eugen Fick successfully manufactured the first contact lens in 1887, the production and use of contact lenses has flourished. Up to now, there are more than 100 million contact lens users worldwide. With the increase of users, various contact lens manufacturing methods have also shown a prosperous situation. There are three more widely known methods, lath cut, spin and injection molding. At present, in the manufacture of soft contact lenses, the most stable injection molding method is most widely used by manufacturers.

Contact lenses, in addition to being a medical material for correcting vision, are worn in the eyes. In addition to traditional contact lenses on the market, some people also print some unique graphics on contact lenses to make the user's eyeballs look bigger and more distinctive, and they are also deeply loved by oriental women. Due to the vigorous development of the market, related patents for the manufacturing method of color contact lenses have also sprung up like bamboo shoots after a rain. The manufacturing method applied to the injection molding method is mainly to print a special pattern on the cover made of contact lenses, and then the cover with the printed pattern is injected into the shape, so that the pattern on the cover is transferred to the lens. However, this transfer method will cause the pigment to fall off slightly, causing the user Security concerns.

The new anti-UV or anti-blue light function on contact lenses is also a product proposed and actually produced by many companies. The main production method is to add anti-UV or anti-blue light materials to the monomer formula for making contact lenses, and then make contact lenses after glue injection and curing. However, the traditional anti-blue light lens will show yellow color, the white area of the eye will show yellow in appearance after the user wears it, which often gives people a bad impression. In order to improve this phenomenon, some manufacturers will use the method of making color films on the periphery of the lens, and print a dark outer ring to modify the effect of yellow on the periphery of the lens.

In view of the shortcomings of the contact lenses listed above, the inventor spent a lot of time investigating relevant knowledge, comparing the advantages and disadvantages, and conducting research and development of related products, and after many experiments and tests, finally launched a "Two-material soft contact lens injection molding process" is to improve the above-mentioned shortcomings to meet the needs of the public.

The main purpose of the present invention is to provide a method for manufacturing contact lenses with two different materials. This method can perfectly combine two materials with different properties to form a contact lens. The important thing is that by joining the two materials, the contact lens can have more powerful capabilities.

The present invention is a two-layer material contact lens manufacturing process. The method includes the following steps: Molding: Put the first material in the center of an arc groove of a lower mold, and then use an arc bump of an upper mold Align the arc groove of the lower mold to close, and a small gap is formed between the arc groove and the arc protrusion, and the first material is placed in the small gap, and then the second material is replaced by a small gap. Pour into the entrance to make the second material The material can completely cover the first material to form a semi-finished product; curing and shaping: send the upper mold and the lower mold together with the semi-finished product into a high-temperature cavity or have ultraviolet or visible light for curing and molding; post-mold processing: wait for the semi-finished product to be cured Then the upper mold and the lower mold are separated, and then the lens is soaked in warm water to soften it to form a finished product.

Through this method of production, a finished product with the first material in the central area and the second material in the outer ring area can be obtained. In this way, the central area and the outer area of the lens can be combined and perfectly connected by different materials. Immaculate purpose. Therefore, the present invention can be described as a very practical and progressive invention, which is worthy of vigorous promotion by the industry and made public.

(S1)‧‧‧Preparation materials

(S2)‧‧‧Mold molding

(S3)‧‧‧Curing and setting

(S4)‧‧‧Post-mold processing

(1)‧‧‧First material

(2)‧‧‧Second Material

(3)‧‧‧ Lower mold

(31)‧‧‧Arc groove

(4)‧‧‧Upper mold

(41)‧‧‧Arc bump

(5)‧‧‧Small gap

(6)‧‧‧Entrance

(7)‧‧‧Semi-finished products

(8)‧‧‧High temperature and high pressure machine

The first figure is a schematic diagram of the process steps of the present invention.

The second figure is a schematic diagram of the movement of the first material of the present invention placed in the arc groove of the lower mold.

The third figure is a schematic diagram of the action of closing the upper mold relative to the lower mold and forming a small gap in the present invention.

The fourth figure is a schematic view of the action of pouring the second material to cover the first material according to the present invention.

The fifth figure is a schematic diagram of the action of the upper and lower molds of the present invention undergoing high temperature and high pressure to solidify semi-finished products.

The sixth figure is a schematic diagram of the post-processing action of the semi-finished product of the present invention.

The seventh figure is a three-dimensional schematic diagram of the finished product of the present invention.

The eighth figure is a schematic cross-sectional view of the Ⅷ-Ⅷ line segment in the seventh figure.

Regarding the technology, means and effects of the present invention, a preferred embodiment is given in conjunction with a detailed description of the drawings. It is believed that the above-mentioned purpose and structure of the present invention And the characteristics, you can get an in-depth and specific understanding. The following is a description of the preferred embodiment, and does not limit the present invention in any form. Referring to the first to eighth figures, the present invention is a two-material soft contact lens injection molding process. The method includes The following steps: Prepare material (S1): Prepare a first material (1) and a second material (2), and the first material (1) and the second material (2) are of different colors, and the A material (1) can block the blue wavelength of 350~530NM; Molding (S2): Place the first material (1) in the center of an arc groove (31) of the lower mold (3), and then use a An arc protrusion (41) of the upper mold (4) is aligned with the arc groove (31) of the lower mold (3) to close, and a small arc is formed between the arc groove (31) and the arc protrusion (41). The gap (5), and the first material (1) is placed in the small gap (5), and then the second material (2) is poured into the small gap (5) through an inlet (6) to make the second The material (2) can completely cover the first material (1) to form a semi-finished product (7); curing and shaping (S3): send the upper mold (4) and the lower mold (3) together with the semi-finished product (7) to a high temperature The high-pressure machine (8) performs curing and molding; post-molding processing (S4): After the semi-finished product (7) is cured, the upper mold (4) is separated from the lower mold (3), and the cured semi-finished product (7) is edged , Polish, then soak the lens in warm water to soften it to form a finished product (9).

According to the description of the above steps, it can be understood that through the cooperation of the first material (1) and the second material (2), the finished product (9) formed can show that the second material (2) covers the first The outer ring of material (1), the advantage of this is that when the first material (1) has a clear color (yellow in this example), if the outer second material (2) can be colorless and transparent, the user is wearing In the present invention, because the yellow material only exists in the area where the black eyeball is located, and the transparent area of the lens is only exposed in the white area of the eye, it can take into account the user's anti-blue light effect, and can have both concealment and aesthetics. , So that the present invention can have multiple functions.

In addition, in the use of the first material (1) and the second material (2), the present invention adopts two materials: Hydrogel and Silicone Hydrogel. (Hydrogel) is a gel with water as a dispersion medium. The water-soluble polymer with a network cross-linked structure introduces a part of hydrophobic groups and hydrophilic residues. The hydrophilic residues combine with water molecules to connect the water molecules inside the network, and the hydrophobic residues swell with water. Things. Hydrogel is a polymer network system, soft in nature, can maintain a certain shape, and can absorb a lot of water; and Silicone Hydrogel (ie hydrogel + silicon Si) ("silicon" is actually used in high oxygen permeability The hard contact lenses of Japan have been quite popular, mainly because they have super high oxygen permeability.) But also because of the limitations of the material, if the contact lens is made of silicone gel alone, it can have higher oxygen permeability. However, it is easy to absorb eye secretions, and the lens material has insufficient toughness and poor comfort. It is not easy to improve the material to achieve various purposes. Therefore, it combines water gel and silicon components with advanced technology to achieve a balance of comfort and high oxygen permeability. Using the manufacturing method of the present invention, silicone gel is used in the center area of the lens, and water gel is used in the area around the center. The superior hydrophilicity and toughness of the hydrogel create comfort for the user, good hydrophilicity, high toughness, and not easy to deposit. However, in the central area, there is a high oxygen permeable silicone hydrogel to provide an endless supply of wearers. The oxygen can be called a multifunctional lens.

Finally, the first material (1) and the second material (2) are placed in the lower mold (3) and the small gap (5) by injection or dripping during the manufacturing process, which are mainly matched with contact lenses: In the form of thin sheets, the finished product (9) obtained through the manufacturing method of the present invention can be worn by the user. Since the two materials are in contact with each other before the reaction, the bonding force formed is compared with After being formed, the power to connect is relatively large, so the first material (1) and the second material (2) of the lens can be firmly joined together to achieve safety in use.

In summary, the present invention "two-material soft contact lens injection molding process" is indeed fully in line with the needs of industrial development in terms of practicability and cost-effectiveness, and the disclosed structure creation also has an unprecedented innovative structure. , So it has "new "Brightness" should undoubtedly be considered, and the present invention can be more effective than the conventional structure, so it is also "progressive". It fully complies with the requirements of China's patent law on the requirements for invention patents. Patent applications are filed in accordance with the law. And I hope that Jun Bureau will review it as soon as possible and give it affirmation.

(S1)‧‧‧Preparation materials

(S2)‧‧‧Mold molding

(S3)‧‧‧Curing and setting

(S4)‧‧‧Post-mold processing

Claims (6)

A two-material soft contact lens injection molding process. The method includes the following steps: preparing materials: preparing a first material and a second material, and the first material and the second material are of different colors, and the first material A material can block the blue light wavelength of 350~530NM; mold molding: place the first material in the center of an arc groove of the lower mold, and then align an arc bump of an upper mold with the arc groove of the lower mold Is closed, a small gap is formed between the arc groove and the arc bump, and the first material is placed in the small gap, and then the second material is poured in through an entrance connected to the small gap to make the second material It can completely cover the first material to form a semi-finished product; curing and shaping: send the upper mold and the lower mold together with the semi-finished product into a high temperature and high pressure machine for curing and molding; post-mold processing: the upper mold and the lower mold are cured after the semi-finished product is cured After separation, the cured semi-finished product is edged and polished, and then the lens is soaked in warm water to soften it to form a finished product. According to the two-material soft contact lens injection molding process described in item 1 of the scope of patent application, the first material and the second material use different materials and different colors. According to the two-material soft contact lens injection molding process described in item 2 of the scope of patent application, the material used for the first material can be: Hydrogel or Silicone Hydrogel. According to the two-material soft contact lens injection molding process described in item 3 of the scope of patent application, the method of placing the first material into the arc groove can be injection or dripping. Manufactured according to the two-material soft contact lens injection molding method described in item 4 of the scope of patent application Process, wherein the material used for the second material is Hydrogel or Silicone Hydrogel, and the color of the second material is different from that of the first material. According to the two-material soft contact lens injection molding process described in item 5 of the scope of patent application, the method of pouring the second material from the inlet can be injection or dripping.

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