JP4564719B2 - Plastic lens dyeing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a plastic lens dyeing method capable of efficiently dyeing at a high density as compared with conventional immersion methods and gas phase methods, and effectively preventing uneven dyeing during dyeing.
[0002]
[Prior art]
In recent years, plastic lenses have been used in many fields instead of glass lenses, but contact lenses and eyeglass lenses used for correcting vision are often used for dyeing lenses for purposes such as cosmetic effects. Yes. As a reason why the glass lens is replaced with a plastic lens, in addition to the light weight and safety of the plastic lens, there is a dyeability that can be easily dyed.
[0003]
For dyeing plastic lenses, an immersion method has been conventionally used. In this method, a dye solution in which a disperse dye having a coloring ability for a plastic lens is dissolved and / or suspended in water is heated, and the plastic lens to be dyed is immersed in the plastic lens for a predetermined time, and then the plastic lens is used. Is heated, and the dye that has penetrated into the lens is further diffused into the lens and stabilized.
[0004]
However, in this method, depending on the concentration of the disperse dye in the dyeing solution, the temperature of the dyeing solution, and the coloring ability of the plastic lens, the color tone of the colored lens is likely to change greatly, and a colored lens having a uniform color tone can be stabilized. It is difficult to obtain. Recently, as a result of the diversification of plastic lens materials in response to market needs for high added value, materials that are difficult to dye by the immersion method are increasing.
[0005]
A gas phase method has been proposed as a method for easily dyeing plastic lenses that have been difficult to dye by the immersion method. As this method, for example, a substrate having a sublimable dye and a plastic lens are opposed to each other at a predetermined interval, and the plastic lens is dyed by sublimating the sublimable dye [for example, Japanese Patent Laid-Open Nos. 1-277814 and 2000- No. 329901 (Patent Documents 1 and 2)] is known. However, in these methods, dyeing is performed with a certain interval between the base and the lens in order to prevent uneven coloring of the colored lens, so that there is a limit to the dyeing density of the colored lens.
[0006]
In order to increase the dyeing density of a plastic lens, an ink receiving layer made of urethane resin or the like is provided on the lens surface, and after sublimation dye is contained in the ink receiving layer, the plastic lens is heated for dyeing [for example, JP-A-8-20080 (Patent Document 3)] has been proposed. However, with this method, it is difficult to remove the ink receiving layer from the colored lens after dyeing.
[0007]
For this reason, a method of dyeing a plastic lens using an ink receiving layer made of a water-soluble polymer containing a sublimable dye and washing the resulting colored lens with water to remove the ink receiving layer [for example, Japanese Patent No. 3074003 (Patent Document 4)] has been proposed. However, in any of the above methods using an ink-receiving layer, it is not possible to obtain a plastic lens dyed at a high density simply by heating and dyeing the plastic lens in the atmosphere. In order to obtain a high-concentration colored lens, heat treatment at a high temperature and / or high temperature is required. However, if the dyeing treatment is performed for a long time, the working efficiency is deteriorated, and if the dyeing treatment is performed at a high temperature, the plastic lens is deformed. There is a problem of end up.
[0008]
Therefore, the present applicant first dyes a plastic lens at a high density efficiently by dyeing a plastic lens provided with an ink receiving layer made of a water-soluble polymer containing a sublimable dye in a heated water vapor atmosphere. (Japanese Patent Application No. 2002-198852). However, in this method, since the water resistance of the ink receiving layer is not so high, the ink receiving layer loses its shape during the dyeing process in a heated water vapor atmosphere, and thus there is a problem that uneven coloring occurs in the colored lens. .
[0009]
[Patent Document 1]
Japanese Patent Laid-Open No. 1-277814 [Patent Document 2]
JP 2000-329901 [Patent Document 3]
JP-A-8-20080 [Patent Document 4]
Japanese Patent No. 3075403 [0010]
[Problems to be solved by the invention]
Accordingly, an object of the present invention is to provide a plastic lens dyeing method capable of dyeing at a high density more efficiently than the conventional immersion method and gas phase method, and effectively preventing uneven dyeing that occurs during the dyeing process. is there.
[0011]
[Means for Solving the Problems]
As a result of diligent research in view of the above object, the present inventors have (a) coloring a plastic lens using an ink-receiving layer that does not lose its shape even in a heated steam atmosphere, so that coloring can be performed with high dye density and leveling in a short time. (B) When a plastic lens has a colored layer contour on its surface, the ink receiving layer does not lose its shape during the dyeing process, and the colored layer contour is clear without bleeding. When polyvinyl alcohol having a polymerization degree of 1000 or more and 2000 or less is used as the ink receiving layer, it was discovered that the ink receiving layer can be easily removed from the colored lens by washing with warm water of 40 to 60 ° C., and the present invention has been conceived.
[0012]
That is, in the method for dyeing a plastic lens of the present invention, an ink receiving layer made of polyvinyl alcohol having a polymerization degree of 1000 or more and 2000 or less is provided on the surface of the plastic lens, and after the sublimation dye is contained in the ink receiving layer, the ink receiving layer is received. The plastic lens provided with a layer is heated in a water vapor atmosphere, and then the ink receiving layer is removed from the plastic lens by spraying warm water of 40 to 60 ° C., thereby dyeing the plastic lens. To do. In the heated steam atmosphere, the temperature is preferably 80 to 200 ° C. and the relative humidity is preferably 50 to 100%.
[0013]
The ink receiving layer is preferably removed from the plastic lens with warm water of 40-60 ° C.
[0014]
As a method for adding a sublimation dye to the ink receiving layer, a method of printing in a desired pattern on the ink receiving layer with an ink jet printer using an ink containing a sublimation dye is preferable.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
[1] Ink Receptive Layer The ink receiving layer of the present invention does not lose its shape due to water absorption even in a heated steam atmosphere. The ink receiving layer preferably has a low affinity with the sublimable dye and can be easily removed from the colored lens after dyeing. As a material for forming such an ink receiving layer, polyvinyl alcohol having a polymerization degree of 1000 or more and 2000 or less is used.
[0016]
When the degree of polymerization is less than 1000, the ink-receiving layer has low water resistance, and the ink-receiving layer absorbs water and loses its shape during the dyeing process in a heated steam atmosphere. If the degree of polymerization is more than 2000, the water solubility of polyvinyl alcohol becomes too low, making it difficult to form a coating solution, increasing the binding property to the lens substrate, and making it difficult to peel off with warm water. Become.
[0017]
[2] Material of plastic lens The material of the plastic lens to which the dyeing method of the present invention is applied is not particularly limited, but the effect of the present invention is particularly remarkable when the material is difficult to dye. Examples of applicable materials include methyl methacrylate homopolymer, copolymer of methyl methacrylate and one or more other monomers, diethylene glycol bisallyl carbonate homopolymer, diethylene glycol bisallyl carbonate and one or more other monomers. Copolymer, sulfur-containing copolymer, halogen-containing copolymer, polycarbonate, polystyrene, polyvinyl chloride, unsaturated polyester, polyethylene terephthalate, polyurethane and the like.
[0018]
[3] Sublimable dye The sublimable dye is not particularly limited as long as it has a property of being sublimated by heating. Examples of such sublimable dyes include Kayaset Blue N (Nippon Kayaku Co., Ltd.), Sumikaron Yellow EG (Sumitomo Chemical Co., Ltd.), Kayaset Blue 906 (Nippon Kayaku Co., Ltd.), Examples include Kayaset Brown 939 (Nippon Kayaku Co., Ltd.). Alternatively, dispersed sublimation dyes may be used, and examples thereof include HANAE II (Sanryu Co., Ltd.) and sublimation ink cartridges for ink jet printers (Eltex Co., Ltd.).
[0019]
[4] Plastic lens dyeing method
(1) Preparation method of ink receiving layer The method of providing the ink receiving layer on the surface of the plastic lens is not particularly limited. For example, a water-soluble polymer solution is prepared by dissolving a water-soluble polymer in an aqueous solvent. After the polymer solution is coated on the surface of the plastic lens, a method of forming a cured film of the water-soluble polymer by heating the plastic lens may be used. Water is preferably used as the aqueous solvent, but an organic solvent having a high affinity for water may be mixed as necessary. When the water-soluble polymer is difficult to dissolve in the aqueous solvent, the water-soluble polymer may be dissolved by raising the temperature of the water-soluble polymer solution to 40 to 80 ° C.
[0020]
The content of the water-soluble polymer in the water-soluble polymer solution is preferably 1 to 30% by weight. When the content is less than 1% by weight, the viscosity of the water-soluble polymer solution becomes too low, and when coating on the surface of the plastic lens, the aqueous polymer solution tends to flow, and a cured film of the water-soluble polymer having the required thickness is formed. It becomes difficult to form. If the content is more than 30% by weight, the viscosity of the water-soluble polymer solution becomes too high, and it becomes difficult to form a cured film of the water-soluble polymer having a uniform thickness on the surface of the plastic lens.
[0021]
The method for coating the water-soluble polymer solution on the surface of the plastic lens is not particularly limited as long as it is a method capable of coating the water-soluble polymer solution on the surface of the plastic lens uniformly with a uniform thickness. Examples of such methods include brushing, dipping, spin coating, and spraying.
[0022]
After the water-soluble polymer solution is coated on the surface of the plastic lens, the plastic lens is heated to a temperature of 20 to 150 ° C. for about 1 minute to 12 hours and dried to form a cured film of the water-soluble polymer.
[0023]
When the plastic lens is dyed using the ink receiving layer of the present invention, the ink receiving layer absorbs water even in a heated water vapor atmosphere and does not lose its shape, so that uneven coloring of the colored lens is effectively prevented. Further, since the ink receiving layer of the present invention is slightly dissolved in warm water of 40 to 60 ° C., the ink receiving layer can be removed from the colored lens by strongly spraying warm water in the above temperature range after the dyeing treatment.
[0024]
(2) Dyeing method of plastic lens In the dyeing method of the present invention, a sublimable dye is contained in the ink receiving layer provided on the surface of the plastic lens by the method of (1), and the plastic lens is heated in a water vapor atmosphere. Dye plastic lenses. There is no restriction | limiting in particular as a method of making a sublimation dye contain in an ink receiving layer, For example, it can carry out by printing etc. Hereinafter, although the dyeing | staining method of the plastic lens of this invention is demonstrated in detail, this invention is not limited to these.
[0025]
FIG. 1 is a schematic view of the staining method of the present invention. As shown in FIG. 1 (a), a sublimable dye is ejected from the nozzle 3 of the ink jet printer onto the surface of the ink receiving layer 2 provided on the plastic lens 1 by the method (1), for example, as shown in FIG. 2 (a). As shown in FIG. 2B, a printing layer 4a having a single sublimation dye attached to a part of the ink receiving layer 2 as shown in FIG. Alternatively, as shown in FIG. 2C, a plurality of printing layers 4a and 4b having a single sublimation dye attached to the ink receiving layer 2 are formed.
[0026]
The obtained plastic lens 1 is fixed to a lens holding member (not shown) and placed in an apparatus (not shown) for forming a heated steam atmosphere. As shown in FIG. 1B, when the plastic lens 1 is heated in a water vapor atmosphere in this state, the molecules of the sublimable dye are sublimated and transferred from the ink receiving layer 2 to the plastic lens 1. Spreads inside. In a heated steam atmosphere, the movement of sublimable dye molecules becomes active, so that the lens can be dyed at a high concentration in a short time. The ink receiving layer 2 is excellent in water resistance and absorbs water even in a heated water vapor atmosphere and does not lose its shape. When the plastic lens 1 has the outline of the colored layer 4a (or colored layers 4a, 4b) on the surface thereof as shown in FIG. 1 (b) or (c), the colored layer 4a (or colored layers 4a, 4b) is formed. ) The outline becomes clear without blurring.
[0027]
After dyeing, as shown in FIG. 1 (c), the ink receiving layer 2 and the remaining sublimable dye (not shown) are removed by the hot water 6 ejected from the nozzle 5 of the washing machine. Thus, when the plastic lens 1 is dyed with the pattern shown in FIG. 2 (a), the plastic lens 1 having the colored layer 7 with high levelness and dyeing density can be efficiently obtained. When the plastic lens 1 is dyed with the pattern shown in (c), in addition to the effects described above, an effect that the outline of the colored layer 4a (or the colored layers 4a and 4b) on the surface of the plastic lens 1 is clear is obtained.
[0028]
The apparatus used for carrying out the dyeing method of the present invention is not particularly limited as long as it can create a heated steam atmosphere. Examples of such devices include autoclaves and pressure cookers.
[0029]
The heating temperature depends on the desired dyeing density, but is preferably 80 to 200 ° C. If the heating temperature is less than 80 ° C., a sufficient dyeing effect cannot be obtained, and if it exceeds 200 ° C., discoloration and deformation of the plastic lens 1 occur. A more preferable heating temperature is 100 to 150 ° C.
[0030]
Although the heating time depends on the desired dyeing concentration, it is usually about 30 to 60 minutes. When the heating time is less than 30 minutes, a sufficient dyeing effect cannot be obtained, and when the heating time is more than 60 minutes, discoloration and deformation of the plastic lens 1 occur.
[0031]
The relative humidity in the water vapor atmosphere is preferably 50 to 100%. If the relative humidity is less than 50%, a sufficient dyeing effect cannot be obtained. If the water vapor atmosphere is supersaturated, water droplets adhere to the surface of the lens substrate, or the ink receiving layer 2 loses its shape. A more preferable relative humidity is 70 to 95%.
[0032]
【Example】
The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto.
[0033]
Example 1
A polyvinyl alcohol (manufactured by Kuraray Co., Ltd., PVA-210 polymerization degree 1000) layer was provided as an ink receiving layer on the surface of a plastic lens made of a thiourethane monomer (Mitsui Chemicals, MR-8). As shown in FIG. 1 (a), an ink containing a sublimable disperse dye for ink jet (manufactured by Sanryu Co., Ltd., HANAE-II) is added to the ink receiving layer 2 by an ink jet printer (manufactured by Mastermind Co., Ltd., MMP-). 900RT) was printed on the pattern shown in FIG. As shown in FIG. 1B, the obtained plastic lens 1 was fixed to a lens holding member (not shown) and placed in a pressure cooker (manufactured by Hirayama Seisakusho). The inside of the pressure cooker was set to 70% relative humidity, and the lens 1 was heated to 130 ° C. and dyed for 1 hour.
[0034]
As shown in FIG. 1 (c), the ink receiving layer 2 and the remaining sublimation dye (not shown) were removed with warm water 6 ejected from the nozzle 5 of the washer. The transmittance of the obtained plastic lens 1 was measured with monochromatic light having a wavelength of 550 nm and found to be 75%. In addition, when the leveling property and the dyeing density of the colored lens 1 were visually checked, it was confirmed that the colored lens 1 was dyed in accordance with the pattern output by the ink jet printer, and the entire lens 1 was dyed uniformly and without any unevenness. It was done.
[0035]
Example 2
In the same manner as in Example 1, the ink receiving layer 2 provided on the surface of the plastic lens 1 was printed, and the obtained plastic lens 1 was fixed to a holding member and then placed in a pressure cooker. As shown in FIG. 1 (b), the inside of the pressure cooker was set to 90% relative humidity, and the lens 1 was heated to 130 ° C. and dyed for 1 hour.
[0036]
As shown in FIG. 1 (c), the ink receiving layer 2 and the remaining sublimation dye (not shown) were removed with warm water 6 ejected from the nozzle 5 of the washer. The transmittance of the obtained plastic lens 1 was measured with monochromatic light having a wavelength of 550 nm and found to be 65%. In addition, when the leveling property and the dyeing density of the colored lens 1 were visually checked, it was confirmed that the colored lens 1 was dyed in accordance with the pattern output by the ink jet printer, and the entire lens 1 was dyed uniformly and without any unevenness. It was done.
[0037]
Comparative Example 1
In the same manner as in Example 1, an ink receiving layer provided on the surface of the plastic lens was printed, fixed to the lens holding member, and then placed in an atmospheric furnace, and the lens was heated to 130 ° C. and dyed for 1 hour. .
[0038]
After removing the ink receiving layer and the remaining sublimation dye with warm water, the transmittance of the colored lens obtained was measured with monochromatic light having a wavelength of 550 nm, and it was 95%. Further, when the leveling property and the dyeing density of the colored lens were visually examined, the entire lens was uneven and the dyeing density was low as compared with the dyed lens in a water vapor atmosphere.
[0039]
【The invention's effect】
As described above, the method for dyeing a plastic lens of the present invention uses an ink receiving layer that does not lose its shape even in a heated steam atmosphere. This makes it possible to (a) obtain a colored lens having a high dye density and levelness in a short time, and (b) when the plastic lens has a colored layer contour on its surface, the colored layer contour is clear without blurring. (C) It is possible to easily remove the ink receiving layer from the colored lens by washing with warm water of 40 to 60 ° C.
[Brief description of the drawings]
FIG. 1 is a schematic view showing a method for dyeing a plastic lens according to the present invention, wherein (a) shows a state of printing on an ink receiving layer provided on the surface of a plastic lens by an ink jet printer, and (b) is obtained. A state where the plastic lens is heated in a water vapor atmosphere is shown, and (c) shows a state where the ink receiving layer is removed from the colored lens.
FIG. 2 is a diagram illustrating a printing surface of an ink receiving layer to which a sublimation dye is attached according to an embodiment of the present invention, and (a) has a printing layer having a single sublimation dye attached to the entire ink receiving layer. (B) is a diagram showing a printing surface having a printing layer having a single sublimation dye attached to a part of the ink receiving layer, and (c) is a drawing showing a single printing surface. It is a figure which shows the printing surface which has several printing layers to which various sublimable dyes adhered.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Plastic lens 2 ... Ink receiving layer 3 ... Nozzle of inkjet printer
4a ・ ・ ・ Printing layer of sublimation dye
4b ... Print layer of another sublimation dye 5 ... Nozzle 6 of washing machine ... Hot water 7 ... Colored layer of plastic lens

Claims (3)

An ink receiving layer made of polyvinyl alcohol having a polymerization degree of 1000 or more and 2000 or less is provided on the surface of the plastic lens, and after the sublimation dye is contained in the ink receiving layer, the plastic lens provided with the ink receiving layer is placed in a water vapor atmosphere. A method for dyeing a plastic lens, comprising: heating, and then spraying hot water of 40 to 60 ° C. to remove the ink receiving layer from the plastic lens, thereby dyeing the plastic lens. The method for dyeing plastic lenses according to claim 1 , wherein the temperature in the heated steam atmosphere is 80 to 200 ° C and the relative humidity is 50 to 100%. 3. The method for dyeing a plastic lens according to claim 1 , wherein printing is performed on the ink receiving layer in a desired pattern by an ink jet printer using the ink containing the sublimable dye.

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