JPS5924825A - Processing method for making surface of contact lens hydrophilic - Google Patents

Abstract

PURPOSE:To improve the wearability of a contact lens, by processing selectively one face of the contact lens with a low-temperature plasma and making the front face of the lens more hydrophilic than the rear face to enhance the washing effect of the rear face of the lens and reducing the sticking of dirt. CONSTITUTION:An annular sample table 41 provided with many holding jigs 40 is put on an annular electrode face 13 placed around a central part electrode 10. The top face of the sample table 41 is formed into an inclined face for the purpose of making it easy to receive the plasma from the central part electrode. When the contact lens to be subjected to the low-temperature plasma processing is fitted to a recessed part of the holding jig 40 and the plasma processing is performed, the hydrophilic property of a lens front face 31 is increased but that of a lens rear face 32 is not changed. The lens rear face 32 of this contact lens whose one face is made more hydrophilic is easier to wash in comparison with a lens whose both faces are made more hydrophilic, and sticking of dirt is reduced, and the wearability is improved for a long time.

Description

DETAILED DESCRIPTION OF THE INVENTION The present defense relates to a method of hydrophilizing the surface of a contact lens, and in particular,
This relates to a method of making one side of the glass hydrophilic.

Currently in use 8: Most of the contact lenses used in IJ are made of hydrophobic resins such as methylmethacrylate-1-resin, and these lenses have hydrophobic surfaces. Disadvantages have been pointed out, such as the feeling of a foreign body when worn, and the fact that it does not get dirty and easily fogs up when worn. In order to overcome these drawbacks, various methods have been proposed for applying hydrophilic treatment to the lens surface of the contact lens 1, and it has been reported that the wetting characteristics can be improved by low-temperature plasma treatment. Conventionally, it has been thought that hydrophilic treatment, which improves the wettability of the lens surface, will help prevent stains from adhering quickly, and hydrophilic treatment can be applied to all surfaces of the lens. It was a wide range of things.

However, according to the research of the present inventors, the whole surface of the Ntaku 1 Helens, which was treated with low-temperature plasma treatment and treated with J, -) to make the whole surface hydrophilic, was more susceptible to corneal damage caused by dirt and grime than the conventional untreated one. It was found that the incidence of inflammation, etc. was increasing, and this was contrary to the conventional thinking mentioned above.

As a result of further research into this origin, the hydrophilicity of the lens surface increased and the culm, 1'A.

(a-> when contact lenses are in contact with the contact lenses and fingers)
I discovered that there is a direction. When using a contact lens, pour a cleaning solution into the storage opening or r and wash it under running water, but due to the concave shape of the back of the lens, cleaning is not sufficient. 4f Straw, n tip l/l = 1 taku 1-Place the lens on the pad of the index finger, including the thumb, but the finger 119 has a convex shape. Therefore, the concave surface of the lens contact surface comes into close contact with the pad of the finger facing the other hand, and there is no rubbing against each other, resulting in insufficient cleaning of this area. :It seems that this problem during cleaning has become more obvious.

Therefore, the inventors of the present invention have worked diligently to eliminate such drawbacks.
As a result of our research, we found that cleaning was performed by performing low-temperature plasma treatment on only the surface of the lens, or by keeping the degree of hydrophilicization of the rear surface of the lens lower than that of the front surface of the lens. We have found that the efficacy is increased and the incidence of corneal inflammation is reduced, leading to this defense.

Contact lens [- To clean the lens, rub the forefinger and thumb together as described above, so it depends on each side whether the front side of the lens is rubbed against the pad of the finger or not. The relative t) is based on the rfA friction coefficient, contact area, etc. In the present invention, the rear surface of the lens is
, 1: It improves the tightness and purity of contact lenses by making them relatively slippery. For this reason, Kibu Mei C does not perform hydrophilic treatment on the rear surface of the lens, or it suppresses the degree of hydrophilicization from the front surface of the lens, so the benefits of hydrophilic treatment are lost on the rear surface of the lens, making it easier to wear. Although it may be slightly inferior in terms of performance, as you remove it and put it on again and again, you will notice a difference in the cleaning effect, and the b effect will become apparent as the wear lees wash away. If the front surface of the lens is wet or not, the lens surface will repeatedly get wet or dry when you blink, and components in tear fluid tend to get dirty and deposit, which can easily cause fogging. . Therefore, if J3 is on this surface, it is preferable to drop J3 on this surface.
4, so between the lens surface and the corner 116)...
Since the liquid is present, the above-mentioned dirt deposition effect occurs. Therefore, when d3 is present on this surface, even if the hydrophilicity is reduced, -C does not have an adverse effect on δ and RI.

Above, the effects of the present invention have been explained in terms of ))-purification effects, but according to the research of the present inventors,
It has been found that certain components in tear fluid are more likely to adhere to the hydrophilic lens surface. It is also possible to reduce the amount of dirt on the rear surface of the lens by covering it with hydrophobic fi+.

Establishing a difference in hydrophilicity on both surfaces of a contact lens is achieved by separately treating each surface of the lens to make it hydrophilic. For this purpose, in the present invention, a suitable contact lens holder is used, and one side of the lens is selectively hydrophilized using low-temperature plasma generated by a specific method.

In low-temperature plasma processing, the emission and J energies of infrared, visible, and ultraviolet radiation, J and electrons, molecular ions, atoms, and atoms are still not fully understood, and sufficient research has not been conducted on processing methods. The current situation is that this is not the case. Conventional low-temperature plasma processing is performed by placing the sample between two electrodes facing each other, and in most cases the two electrodes are placed in a series position, but in this method, the sample is placed between two electrodes that face each other. There is a limit to the number of samples that can be processed, and if a plurality of samples 1 are placed between both electrodes, the positional relationship between the electrodes will differ for each sample, resulting in uneven processing. In addition, since strong energy (=I) is applied and the LC ions act on the sample in a linearly accelerated manner, the processing becomes excessive and is particularly susceptible to the position of the sample, which also causes uneven processing. It had the disadvantage of being easy.

The present invention solves such problems, and also provides a method that can process a large number of contact lenses at the same time and uniformly hydrophilize the contact lenses. Optical properties and lenses! l! ■
(By selectively making one side of the lens hydrophilic to a desired degree without impairing its properties, improving its wetting properties and enhancing wearability, as well as improving the lens cleaning effect as described above.) The purpose is to avoid a decrease in Rire (=J arrival).

The following is a summary of the present invention.

This defense is based on the following: Contact 1 - Holding the lens periphery tightly and tightly touching either the front surface of the lens or one side of the scene.
In the state of i', attach the lens to the holder and apply an electric current L to two planar electrode surfaces located in approximately the same plane in the dilute gas. The feature is that by selectively treating one side of the contact lens with a low-toned plasma generated by the liquid, the front surface of the contact lens becomes more hydrophilic than the back surface of the contact lens.

The holder should be one that is dense enough to prevent one side of the contact lens from being affected by the low-temperature plasma during treatment, and the other side open to the low-temperature plasma.The overall shape of the two electrodes is It is not particularly limited,
~'tJ7 it ([The only requirement is that the electrode surfaces that act on plasma generation in the gas are located in approximately the same plane. As long as this requirement is met, the specific shape of the electrode can be varied. A wide variety of variations are possible.

Two planar electrode surfaces are placed around the central electrode surface and its surroundings.
+ff-! If the structure is made up of 8 annular electrode surfaces, the positional relationship between the electrode surfaces will be equalized, and the generated plasma will also be equalized, making it effective for processing a large number of samples without uneven processing. be. The treatment target “=1tank1-lens” is, for example, methyl methacrylate-1~resin,
Although the contact lens is made of silicone resin or a copolymer containing silicone resin as a component, the present invention is also applicable to contact lenses made of hydrophobic resins other than these. The effectiveness of plasma treatment depends on parameters such as dilute gas pressure, type of power source, voltage, current, and treatment time, but the effects of these parameters are It is not possible to uniformly specify a preferable tea juice because it is greatly influenced by the structure of the tea, and it is necessary to select the suitable tea juice for each implementation.
Typical gases include air, oxygen, helium, argon, etc., but oxygen or gas containing it is preferred. Containing a small amount of water vapor in these scum is particularly effective in making it hydrophilic. The gas pressure (degree of vacuum) is approximately 0.1 to ITOrl·. The power source may be either a DC power source or an AC power source. Since the aspect of plasma generation differs depending on the type of power source, it is necessary to adjust the sample mounting location and each parameter to the desired extent.

Next, the present invention will be described in detail based on a preferred embodiment shown in the accompanying drawings.

FIG. 1 is a cross-sectional view of an embodiment of a processing section of a low-temperature plasma processing apparatus used in the method of the present invention.

However, the contact lens holder shown in FIG. 1 is different from the one according to the present invention for comparison. The electrodes consist of a central electrode 10 on the right side of a circular electrode surface 11, a peripheral electrode 12 on the right side of an annular electrode surface 13 located around the periphery, and are insulated from each other by an insulator 14. Although the peripheral electrode 12 appears to be separated left and right in the figure, it is an integral annular electrode when viewed from both directions. Both the central electrode 10J5J and the peripheral electrode 12 are connected to the housing 15 (only a portion of which is shown in the figure). ).

A Pelger 17 is placed on the base 15 via a backing 16, and a plasma generation space 18 is formed therein. The lens to be hydrophilized is held on an annular sample stage 18 placed on the annular electrode surface 13p so as to surround the circular electrode surface 11. When performing plasma treatment, first close the gas introduction pipe 20,
After connecting the gas exhaust pipe 21 to a vacuum pump (not shown) to create a vacuum of 0.0170 rr or less in the plasma generation space 18, the gas to be used is introduced through the gas introduction pipe 20J to a predetermined gas pressure. J (0,1 to 11 orr).

The voltage applied to both electrodes by the power source 22' is preferably an alternating voltage. In the case of an AC power source, a ring-shaped low-temperature plasma is attached to the valve near the sample stage A in Fig. 1, so test 1'z1 is 9. Evenly many times in i'i time 1
11. In the case of a DC power supply, it is more efficient to load the sample r1 on the cathode side. fn iv
In the case of an example using 1 l-orr of air as the gas,
In the case of any power source, bQf is desirable, i'1 is a voltage of 400 to 800 V, a current of 4 to ε301Δ, and a processing time of 33 to 10 minutes. When processing JIP with the same electric power, AC can process the process in a shorter time than DC.c5-
Ru.

Figure 2 is an I-side view of 21 contact lenses 30 made of methyl methacrylate resin, where 31 is the front surface of the lens and 32 (J lens 1). The measurement characteristic 111 on the lens surface is the contact angle of water droplets, which is about 60° to about 70' frl
It is.

Here, the contact angle is the angle formed between the lens surface and the water droplet surface when a water droplet is placed on the lens surface, and the more hydrophilic the lens surface is, the smaller the contact angle becomes.

First of all, in order to increase 1 Eikawa 1 level, contact lenses 30
Both surfaces of the lens front surface 31;
Low-temperature plasma treatment was performed for 6 minutes using an AC power source with a voltage of 500 V and a current of 5111 A in the air of RR. As a result, the 1a antennae of the water droplet was 66°, but the angle on both sides was approximately 4°.
1. This hydrophilic treatment on both sides reduced the degree of culm to 0°. At first, the wearability was good and patients evaluated it highly, but after using it for several months, the conventional untreated J (P lens) Therefore, the contact angle is 066° with both surfaces, and the lens is attached to contact 1, which has a contact angle of 0.66° with both surfaces, as shown in Figure 3. Low-temperature plasma treatment was carried out using a ring-shaped sample stage 41 with a large number of holders 40 shown enlarged in FIG. 4 on its surface. The holder 40 is attached to the inclined top surface -F (=J) of the sample stage 41 via the protrusion 42 at the bottom. This is to make it easier to receive plasma from Toden (~10).

The sample stage 41 with the contact lens 1 and the lens attached is shown in Figure 6. #'r When only the front surface of the lens 31 was plasma treated with the same strip 1'1 as described above, the 1a antennae of lens 6γj decreased to approximately 40°, but the contact angle of the rear surface of the lens decreased by 6°C. There wasn't. This contact lens has a hydrophilic treatment on both sides (1'3) (compared to a contact lens that has been treated with water), it is easier to wash the lenses with 1 crotch 32, and a lens that has been treated with hydrophilic treatment on both sides. Compared to 11111, the rate of staining on the floor in the evening was reduced to one-fiftieth.The contact angle of the lens surface was approximately 6o on both sides.

After the hydrophilic treatment, plasma treatment was performed on only the front surface 31 of the lens (front surface 31Q) to further increase the contact angle to approximately 40°, and then the cleaning process was performed in the same manner as above.
From Song Dynasty.

Historically, according to the present invention, contacts 1 to lenses can be treated at the same time.
jl unevenness 4 [can be processed in large numbers and has little effect on heat/,
1, so it is transparent <'K (ffl fat is white) The surface of the lens is appropriately hydrophilized without changing to 4M. It is possible to improve wetting characteristics without

The effects of the present invention are clearly seen in the Examples shown below.

[Example 1] As shown in FIG.
A comparative experiment was carried out to compare the adhesion of sample pieces 52 of various properties to the chamois by spraying a contact lens cleaning solution 9 (anionic surfactant agent) or water onto the chamois. Chamois is the skin of a small deer and corresponds to the characteristics of human finger skin. A thread 53 is connected to one end of the sample 52, and a weight 5 is attached to the other end of the thread.
5" (), sample piece 5 is removed with a constant force through the erasing wheel 4.
I tried to pull 2. The sample was first pressed against the chamois with a constant pressure, and the time from when this pressure was released until it began to slide was measured. The same experiment was conducted several times, and the average values are shown in Table 1. In Table 1, sample piece A Onibi C is γ-methacrylo 1: shibu 11 pill 1 heliethoxysilane (manufactured by Shin-Etsu Chemical).

Copolymer of product name K II l'E-503) (5 parts by weight) and methyl methacrylate-1.(1) 5 parts by weight, sample 11 pieces Polymer, sample piece E is K B E-503 (50-fold portion)
and methyl methacrylate-t-(,'+0 middle M part)'ξ
It is a polymer. In the case of plasma treatment, the hydrophilic treatment was carried out in the air of 0.2 l-orr for 6 minutes using an AC power source with a voltage of 500 V and a current of 5 IllA using the apparatus shown in FIG. In the case of acid treatment, the sample was treated with an acid-resistant aqueous solution of No. 0113-4 for 30 minutes. According to these results, it is clear that in the case of specimens made of the same rope material, the adhesion of the culm and PM skin, whose surfaces become hydrophilic, increases; It can be seen that f is largely dependent on the contact angle of the surface.

[Example 21] In order to compare the ease with which stains adhere to various sample pieces while avoiding changes in wettability, 0% of lysodeme, a component in tear fluid, was used.
．． A study was conducted using a 5% by weight solution. The material J5 and surface treatment of the sample pieces are shown in Table 1. Each sample piece was immersed in the lysozyme solution described above, pulled out, dried, and dipped again. Repeatedly, the sample pieces were dipped in the lysozyme solution and the lysozyme solution was removed. As a result, sample piece C had less (q arrival) than sample piece A d3 J: and B.

Example Methyl methacrylate 1 - Resin contact 1 - Twelve lenses shown in Figure 6 were placed in an annular manner on a sample table 41, and the pressure inside the verge P-18 was reduced to below 110,000 liters. After that, keep the air pressure around 0.2 Torr and increase the voltage to 50 Torr.
Low-temperature plasma treatment was performed using an AC power source with a current of 0 V and a current of 5 mA for a treatment time ranging from 2 to 9 minutes. The wettability of the front surface of the lens was good for all treatment times, and was particularly good for treatment times of 5 to 9 minutes. In addition, there was almost no variation in vigor between individual lenses. Just wet t[(
Regarding paternity (111 is also good 1 for 6 of 16 minutes processing)T
There was 'c.

Example 4] The front voltage was fixed at (i (IOV), the power was 1.5A)
The test was carried out in the range of 55W on the 7th day.Methyl methacrylate-1 resin T1 tank 1-1 with the same strip 1'1 as in Example 3
The lens was treated to make it hydrophilic. Under any power (current), J3 was rated good. However, when using J5 under a power of 4W or more, γ71 due to Nj due to individual lenses
It is easy for variations in the value to occur.

[Example 5] The current was fixed at 3 mA, and the power was in the range of 1.5 to 5 W. The wettability 111 was good under any power (voltage).However, under a power of 4W or higher, variations in wettability among IIM lenses tend to occur, : Discoloration and deterioration of the lenses were observed.

[Example 61 Electric power: 1.5 to JW% Treatment time: 2 to 10 minutes, using both DC and AC power sources. Resin contact 1 Hellens was treated to make it hydrophilic. Although it was possible to obtain good 4-way demand with direct current and alternating current, in general, alternating current had a better treatment effect. In the case of alternating current, an annular low-temperature plasma is generated near the sample stage 41 in Fig. 6 along this line, and in this area there is less heat shadow %5.1, and many lenses can be processed simultaneously without uneven processing. We were able to apply hydrophilic treatment to the material. In the case of 1 DC current, the cathode side was more efficiently hydrophilized.

[Example 71 Electric power (AC) 2 to 4.5 W, treatment time in the range of 2 to 10 minutes, and a gas pressure of about 0.2 Torr.
We investigated the influence of the type of gas on the hydrophilization of . The residue was air, oxygen, nitrogen, argon, low humidity air, and high humidity air, and an improvement in wet bamboo was observed in each case. However, long-term wetting durability 11 differed depending on the type of gas. In particular, scum containing oxygen and high-humidity gas showed good results in terms of wettability (1) and durability.

[Example ε3] In the above Example 1, the lenses of contact lens 1 subjected to hydrophilic treatment showed a decrease in the resistance to crystallization due to drying.
However, the product is stabilized by being immersed in water after plasma blast treatment, and even after that, it is stabilized by soaking in water.
[Lori lasted. Furthermore, the optical characteristics of the contact lenses (which exhibited good irradiation resistance) are fully satisfactory.

[Comparative Example] A plasma photogeneration device in which two electrode surfaces face each other was used under the same conditions as in the above example (methyl methacrylate-1 to resin: I-tact I, hydrophilicization of the lens). Although the treatment was carried out, the treatment tends to be excessive and the range of the optimum treatment strip A'1 is narrow, so the effect was uneven depending on the position of the strip A'1 and sample H.Also, sufficient wetting ↑ (1 is A) In some cases, the lens surface became internally heated due to the influence of heat without being exposed to heat.

[Brief explanation of drawings]

FIG. 1 shows the processing section 1 of a low-temperature plasma apparatus for carrying out the method of the present invention. J Longitudinal QMi shown with some changes for comparison
The top view, Figure 2 is a vertical cross-sectional view of the contact lens, and Figure 3 (
J Slope view of the sample stage used for carrying out the method of the present invention,
Figure 4 is a perspective view of the holder for fitting and holding the lens into the contact lens 1, and Figure 5 is a perspective view of the holder shown in Figure 4] Contact 1
〜An end view of the vertical IO'i with the lens fitted, FIG. 6 is a processing section of a low temperature plasma apparatus for carrying out the method of the present invention by attaching a contact L-lens to the 11 test units shown in FIG. 3. FIG. 7 is a simplified diagram of the adhesion test load.

Claims (7)

[Claims] (1) Hold the periphery of the lens in close contact with either the front or rear surface of the lens, attach the lens to the holder, and use the diluted gas. selectively treating one side of the contact lens with low-temperature plasma generated by applying a voltage to two planar electrode surfaces located within substantially the same plane; A method for making the surface of a contact lens hydrophilic, characterized by making the front surface of the contact lens more hydrophilic than the rear surface of the contact lens. (2) Said? The contact lens surface hydrophilic treatment method according to claim (1), wherein t2[ is connected to an AC power source. (3) The contact lens surface according to claim (1) or (2), wherein the two planar electrode surfaces include a central electrode surface and an annular electrode surface located around the central electrode surface. Hydrophilic treatment method. (4) The voltage is derived from an AC power supply, and the contact lens is processed in an annular low-temperature plasma generated on the entire surface of the annular electrode.
A hydrophilic treatment method for the surface of a contact lens described in . (5) The diluted gas is air or oxygen (a hydrophilic treatment agent for a contact lens surface according to any one of claims (1) to (4)). (6) The contact lens mentioned above is methyl methacrylate-1-
♀31 of the contact lens surface according to any one of claims (1) to (5); Water treatment method. (7) The holder has a contact lens diameter and L'f
It is equipped with four cylindrical parts with the same diameter,
The contact 1 to the lens surface according to any one of claims (1) to (6), wherein a lens is fitted to the contact 1 into the cylindrical four parts and the low temperature plasma treatment is performed. Hydrophilic treatment method.