Contact lens ink resin as well as preparation method and application thereof

Abstract

The invention belongs to the field of color contact lenses, and particularly relates to contact lens ink resin as well as a preparation method and application thereof. The method comprises the following steps: 1) preparing a mixture of a monomer, a solvent and a photoinitiator, 2) curing the monomer mixture with ultraviolet light, 3) controlling viscosity accumulation, and 4) activating with an adhesion promoter and the photoinitiator. And the filler does not contain a cross-linking agent or a chain transfer agent. The prepared resin can be used as a base film layer coating and a pigment layer coating. The resin is suitable for transfer printing and UV curing, and cannot be contaminated by pigments.

Description

Technical Field

[0001] The invention belongs to the field of colored contact lenses, and in particular relates to a contact lens ink resin and a preparation method and application thereof. Background Art

[0002] Cosmetic lenses are popular because their unique patterns can enhance the beauty of the wearer's eyes. In order to meet the demand, many methods and compositions have been developed to improve the quality of these lenses. For example, well-known foreign ink composition patents include U.S. Patent No. 4,668,240 to Loshaek, U.S. Patent No. 5,272,010 to Quinn, and U.S. Patent Application No. 2003 / 0054109 to Quinn et al. These patents disclose ink compositions including at least one pigment dispersed in a resin. The resin may have one of the reactive groups, such as -COOH, OH, -NH-R, where R may be hydrogen or a C1-C8 alkyl group. The ink composition may have an addition compound having a functional group -NCO or epoxy group. Other patents for similar compositions for printing inks include U.S. Patent No. 5,272,010, and U.S. Patent Application No. 2003 / 0054109 to Quinn et al. Patents Nos. 5,414,477 and 4,857,072 follow the same pattern technically, namely having one or more pigments, a resin with functional groups, a suitable solvent for assisting printing, and an adhesion promoter to crosslink or bond the pigment to the lens material. These ink compositions can be cured by known methods, such as thermal curing or UV curing using an appropriate initiator. The ink composition may also contain a crosslinking agent or a chain transfer agent. Typically, the viscosity buildup of the resin is controlled by adjusting the ratio of monomer to solvent or using a small amount of a chain transfer agent or a crosslinking agent or a combination thereof. However, this further complicates the resin production process and is known to change the curing time and quality of the printed pattern. The production process also requires slowly mixing the monomer mixture into the solvent at high temperature for several hours, ranging from 5 to 16 hours or even longer. Controlling the production process of the resin for a long time at higher temperatures makes it difficult to handle.

[0003] Therefore, it is necessary to design a simple, fast and easy-to-operate resin manufacturing process for transferring ink patterns on the surface of contact lenses. Summary of the invention

[0004] Prior art documents provide methods for preparing resins by thermally reacting a mixture of polymerizable monomers and solvents to obtain polymers having a viscosity suitable for printing inks. As far as is known, there has been no report on the preparation of resins by polymerizing monomers by UV curing methods.

[0005] In order to solve the above-mentioned technical problems, this application provides the following technical solutions:

[0006] The present invention provides a method for preparing a contact lens ink resin, comprising the following steps:

[0007] S1: mixing a primary hydrophilic monomer, a secondary hydrophilic monomer, a primary hydrophobic monomer, a secondary hydrophobic monomer, a tertiary hydrophobic monomer, a primary solvent, a secondary solvent and a photoinitiator to obtain a polymerization stock solution;

[0008] S2: irradiating the polymerization stock solution under an ultraviolet light source for 10-180 minutes to obtain a polymerization reaction mixture;

[0009] S3: adding an inhibitor to the polymerization reaction mixture, stirring the mixture at room temperature (25±5° C.) until the viscosity of the mixture is 400-900 cps, to obtain a mixed resin;

[0010] S4: adding a pigment, an adhesion promoter, a primary photoinitiator and a secondary photoinitiator to the mixed resin to disperse and obtain the contact lens ink resin;

[0011] In the step S1, the polymerization stock solution includes the following components by weight: 28-45% of a primary hydrophilic monomer, 0.1-5% of a secondary hydrophilic monomer, 0.1-1% of a primary hydrophobic monomer, 0.1-0.8% of a secondary hydrophobic monomer, 0.1-1.2% of a tertiary hydrophobic monomer, 30-50% of a primary solvent, 5-20% of a secondary solvent, and 0.05-1.2% of a photoinitiator;

[0012] In step 4, the dispersed mixture contains, by weight, 2-10% of pigment, 2-10% of adhesion promoter, 0.5-5% of primary photoinitiator and 0.5-5% of auxiliary photoinitiator.

[0013] Preferably, the primary hydrophilic monomer and the secondary hydrophilic monomer are independently selected from hydroxyethyl methacrylate (HEMA), hydroxyethyl acrylate (HEA), 2-hydroxypropyl methacrylate (HPMA), dimethylacrylamide (DMA), methacrylic acid (MA), N-vinyl pyrrolidone (NVP), N-hydroxymethylacrylamide (NHMA), acrylic acid (AA), N,N-dimethylacrylamide (DMAA), 2-hydroxypropyl acrylate (HPA), vinyl alcohol (VA), 2-hydroxyethylacrylamide (HEAA) or methoxy polyethylene glycol methacrylate (MPEGMA).

[0014] Preferably, the main solvent and the secondary solvent are independently selected from ethyl acetate, ethylene carbonate (EC), n-butanol (NBA), alcohol, xylene, toluene, N-methyl-2-pyrrolidone (NMP), cyclopentanone, cyclohexanone, methyl ethyl ketone (MEK), acetone, dimethylformamide (DMF), dimethyl sulfoxide (DMSO) or tetrahydrofuran (THF).

[0015] Furthermore, the alcohol is selected from methanol, ethanol, propanol or isopropanol.

[0016] Preferably, the primary hydrophobic monomer, the secondary hydrophobic monomer and the tertiary hydrophobic monomer are independently selected from methyl methacrylate (MMA), ethyl methacrylate (EMA), 2-ethylhexyl methacrylate (2-EHMA), butyl methacrylate (BMA), glyceryl methacrylate (GMA), ethoxyethyl methacrylate (EOEMA), styrene monomer, ethyl methacrylate (EMA), propyl methacrylate (PMA), butyl methacrylate (BMA), hexyl methacrylate (HMA), isobornyl methacrylate (IBOMA), lauryl methacrylate (LMA), 2-ethylhexyl methacrylate (2-EHMA) or isobutyl methacrylate (IBMA).

[0017] Preferably, the intensity of the ultraviolet light source is 500-1500 mW / cm 2 , the ultraviolet wavelength is 330-395nm.

[0018] Preferably, when a light bulb is used as the light source, the intensity of the light bulb is 50-100 mW / cm 2 between.

[0019] Preferably, in step S3, the inhibitor is selected from 4-hydroxy-TEMPO (4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl free radical), butylated hydroxytoluene (BHT), hydroquinone (HQ), hydroquinone monomethyl ether (MEHQ), tert-butylcatechol (TBC), phenothiazine (PTZ) or benzoquinone;

[0020] Preferably, in step S3, the inhibitor is added at a concentration of 100-250 ppm.

[0021] Preferably, the adhesion promoter is selected from hexamethylene diisocyanate (HDI), toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), isophorone diisocyanate (IPDI), methacryloyloxyethyl isocyanate (MOI), tetramethylene diisocyanate (TMDI), 2,4-toluene diisocyanate (2,4-TDI) or methacryloyloxyethyl isocyanate (MOI).

[0022] Preferably, the pigment is selected from ferric oxide (iron (III) oxide), cadmium sulfide (CdS), cadmium selenide (CdSe), lead tetroxide (Pb3O4) or an organic pigment; the organic pigment is selected from perylene red or anthraquinone red.

[0023] Preferably, the photoinitiator, the primary photoinitiator and the auxiliary photoinitiator are independently selected from benzoin derivatives, acylphosphine oxides, hydroxyalkyl phenones or benzyl ketals.

[0024] Furthermore, the benzoin derivative is selected from benzoin methyl ether (BME), benzoin ethyl ether (BEE), benzoin isobutyl ether (BIPE) or benzoin butyl ether (BBE).

[0025] Furthermore, the acylphosphine oxide is selected from diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO), bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide (BAPO) or ethyl(2,4,6-trimethylbenzoyl)phenylphosphonate (TPO-L).

[0026] Furthermore, the hydroxyalkyl phenone is selected from 2-hydroxy-2-methyl-1-phenylpropan-1-one 1-Hydroxycyclohexylphenylketone 2-Hydroxy-1-(4-(2-hydroxyethoxy)phenyl)-2-methyl-1-propanone

[0027] Furthermore, the benzyl ketal is selected from benzyl dimethyl ketal (BDK), 2-benzyl-2-(dimethylamino)-1-(4-morpholinophenyl)butanone-1

[0028] Specifically, the preparation method of the contact lens ink resin comprises the following steps:

[0029] Step 1: In a transparent beaker, add 28-45 wt % of the primary hydrophilic monomer, 0.1-5 wt % of the secondary hydrophilic monomer, 0.1-1 wt % of the primary hydrophobic monomer, 0.1-0.8 wt % of the secondary hydrophobic monomer, 0.1-1.2 wt % of the tertiary hydrophobic monomer, 30-50 wt % of the primary solvent, 5-20 wt % of the secondary solvent, add 0.05-1.2 wt % of the photoinitiator, and stir with a magnetic stirrer until uniform.

[0030] Step 2: Expose the mixture to an ultraviolet light source. The intensity of the ultraviolet light source is set between 500-1500mW / cm2. The wavelength of the ultraviolet light is 330nm to 395nm, and the illumination time is 10 minutes to 3 hours.

[0031] Step 3: The third step is to stop the polymerization to obtain the desired viscosity. Add a suitable inhibitor and mix it into the resin by mechanical or magnetic stirrer. The amount of inhibitor added to the resin is between 100-250ppm. Continue stirring until the resin reaches a viscosity between 400-900cps at room temperature. The resin can be used without further purification.

[0032] Step 4: Add 2-12 wt% of pigment, 2-10 wt% of adhesion promoter, 0.5-5 wt% of primary photoinitiator and 0.5-5 wt% of auxiliary photoinitiator to prepare ink. The prepared ink is suitable for printing on plastic surfaces and used in contact lens technology.

[0033] The present invention also provides a contact lens ink resin prepared by the preparation method.

[0034] The present invention also provides application of the contact lens ink resin, and the contact lens ink resin is printed on a plastic surface to prepare a contact lens.

[0035] The technical solution of the present invention has the following advantages over the prior art:

[0036] The resin manufacturing process outlined in this invention proposes a completely different UV-initiated polymerization method. The main components of the resin formulation are hydrophilic monomers with hydroxyl functional groups (-OH). Compared with thermal polymerization methods, these hydroxyl functional groups polymerize very quickly under a UV light source. The UV-initiated method is superior to the thermal method because the power, intensity and time of the UV light source can be controlled to obtain the desired viscosity. However, during the thermal curing process, a cross-linking agent or chain transfer agent needs to be added to control the viscosity of the resin. In addition, UV-initiated polymerization does not require continuous stirring or reflux condensation to prevent high-temperature solvent evaporation. The viscosity of the UV-made resin is suitable for pad printing on plastic substrates. When dispersed with inorganic pigments, the resin can be used as a base layer as well as an ink pattern layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is the molecular weight data diagram of Comparative Example 1.

[0038] Figure 2 This is the molecular weight data diagram of Comparative Example 2.

[0039] Figure 3 This is an example of the normal printing effect of UV resin.

[0040] Figure 4 This is an example of a non-printable UV resin.

[0041] Figure 5 This is an example of the effect of UV resin dry adhesive printing.

[0042] Figure 6 This is an example of wet printing effect. DETAILED DESCRIPTION

[0043] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0044] Methacrylate MA, styrene monomer SM, glycerol methacrylate GMA, methyl methacrylate MMA, hydroxyethyl methacrylate HEMA, ethylene carbonate EC, n-butanol NBA, 1-hydroxycyclohexyl phenyl ketone HPK 184, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide Darocur 819.

[0045] Example 1

[0046] The secondary hydrophilic monomer methacrylic acid MA 0.2%, the hydrophobic monomer styrene monomer SM 0.41%, the hydrophobic monomer methacrylate glycerol GMA 0.82%, the hydrophobic monomer methyl methacrylate MMA 0.62%, the primary hydrophilic monomer hydroxyethyl methacrylate HEMA 33.11%, the primary solvent ethylene carbonate EC 55.22% and the secondary solvent n-butanol NBA 9.62% are placed in a transparent beaker. The photoinitiator 1-hydroxycyclohexyl phenyl ketone HPK 1840.1% is added to the total weight percentage of the mixture. The mixture is stirred until uniform. The beaker is placed at 1000mW / cm 2 60 min under UV light. UV wavelength is 395 nm. Add inhibitor 4-hydroxy-TEMPO to 150 ppm to stop viscosity increase. See Table 1 for time and intensity. Stir the resulting resin to room temperature.

[0047] Example 2

[0048] The secondary hydrophilic monomer methacrylic acid MA 0.2%, the hydrophobic monomer styrene monomer SM 0.41%, the hydrophobic monomer methacrylate glycerol GMA 0.82%, the hydrophobic monomer methyl methacrylate MMA 0.62%, the primary hydrophilic monomer hydroxyethyl methacrylate HEMA 35.11%, the primary solvent ethylene carbonate EC 53.22%, the secondary solvent n-butanol NBA 9.62%, and the photoinitiator HPK 1840.1% are added into a transparent beaker, and the added amount is calculated by percentage of the total weight of the mixture. The rest of the resin preparation process is the same as that in Example 1.

[0049] Example 3

[0050] Add the secondary hydrophilic monomer methacrylic acid MA0.2%, the hydrophobic monomer styrene monomer SM 0.41%, the hydrophobic monomer methacrylate glyceride GMA0.82%, the hydrophobic monomer methyl methacrylate MMA0.62%, the primary hydrophilic monomer hydroxyethyl methacrylate HEMA41.11%, the primary solvent ethylene carbonate EC 47.22%, the secondary solvent n-butanol NBA9.62%, and the photoinitiator HPK 1840.1% into a transparent beaker, the added amount is calculated by the total weight percentage of the mixture, and the ultraviolet irradiation time is 15 minutes. The rest of the resin preparation process is the same as in Example 1.

[0051] Example 4

[0052] The preparation process is the same as that of Example 3, except that the ultraviolet irradiation time is 19.5 min.

[0053] Example 5

[0054] The preparation process is the same as that of Example 3, except that the ultraviolet irradiation time is 20 minutes.

[0055] Example 6

[0056] The preparation process is the same as that of Example 3, except that the ultraviolet irradiation time is 22 minutes.

[0057] Example 7

[0058] The preparation process is the same as that of Example 3, except that the ultraviolet irradiation time is 24 minutes.

[0059] Table 1 Effect of curing time and monomer content on viscosity

[0060]

[0061] Application Example 1

[0062] The binder solution finally obtained in Examples 1 to 7 was activated by adding HDI 4%, and inorganic pigment ferric oxide 5%, photoinitiator 8191% and HPK 184 3% were added to the ink. The ink was dispersed by multi-stage centrifugation. The pad printing ink results are shown in Table 2.

[0063] Table 2 Effect of viscosity on printing quality

[0064] Example HDI% Iron(III) oxide, % Basement membrane Ink dot pattern Printing Effect 1 4 5 Wet and bubbly Non-stick not good 2 4 5 dry Very sticky not good 3 4 5 No basement membrane formed Not printable Not printable 4 4 5 A bit wet Normal A bit wet 5 4 5 Normal Normal good 6 4 5 Normal Normal good 7 4 5 sticky Dry, sticky dry

[0065] Comparative Example 1

[0066] The same raw materials as in Example 3 were weighed and UV cured according to the procedure described in Example 1. The monomer content was 43.16%, the solvent content was 56.84%, and the UV curing temperature was 1000 mW / cm 2 The intensity of the UV LED light source was set to 20%. The curing time was 19.5 minutes. 150 ppm of 4Hydroxy-TEMPO was added to control the viscosity increase of Comparative Example 1 to 580 cps and the viscosity increase of Comparative Example 2 to 1200 cps.

[0067] Comparative Example 2

[0068] The same raw materials as in Example 3 were weighed and UV cured according to the procedure described in Example 1. The monomer content was 43.16%, the solvent content was 56.84%, and the UV curing temperature was 1000 mW / cm 2 The intensity of the UV LED light source was set to 20%. The curing time was 22 minutes. 150 ppm of 4Hydroxy-TEMPO was added to control the viscosity increase of Comparative Example 1 to 580 cps and the viscosity increase of Comparative Example 2 to 1200 cps.

[0069] Table 3 Effect of viscosity on printing quality

[0070] Comparative Example Viscosity(cps) Mp Mn M Mz Mv PDI 1 580 205283 99605 296826 642916 258793 2.98 2 1200 300814 146722 2126654 12545850 1462480 14.49

[0071] In Table 3, Mp is the peak molecular weight, Mn is the number average molecular weight, Mw is the weight average molecular weight, Mz is the Z average molecular weight, Mv is the viscosity average molecular weight, and PDI is the polydispersity index.

[0072] Obviously, the above embodiments are merely examples for clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the protection scope of the invention.

Claims

1. A method for preparing a contact lens ink resin, characterized in that: The steps include: S1: mixing a primary hydrophilic monomer, a secondary hydrophilic monomer, a primary hydrophobic monomer, a secondary hydrophobic monomer, a tertiary hydrophobic monomer, a primary solvent, a secondary solvent and a photoinitiator to obtain a polymerization stock solution; S2: irradiating the polymerization stock solution under an ultraviolet light source for 10-180 minutes to obtain a polymerization reaction mixture; S3: adding an inhibitor to the polymerization reaction mixture, stirring the mixture at room temperature until the viscosity of the mixture is 400-900 cps, to obtain a mixed resin; S4: adding a pigment, an adhesion promoter, a primary photoinitiator and a secondary photoinitiator to the mixed resin to disperse and obtain the contact lens ink resin; In the step S1, the polymerization stock solution includes the following components by weight: 28-45% of a primary hydrophilic monomer, 0.1-5% of a secondary hydrophilic monomer, 0.1-1% of a primary hydrophobic monomer, 0.1-0.8% of a secondary hydrophobic monomer, 0.1-1.2% of a tertiary hydrophobic monomer, 30-50% of a primary solvent, 5-20% of a secondary solvent, and 0.05-1.2% of a photoinitiator; In step 4, the dispersed mixture contains, by weight, 2-10% of pigment, 2-10% of adhesion promoter, 0.5-5% of primary photoinitiator and 0.5-5% of auxiliary photoinitiator.

2. The preparation method according to claim 1, characterized in that The primary hydrophilic monomer and the secondary hydrophilic monomer are independently selected from hydroxyethyl methacrylate, hydroxyethyl acrylate, 2-hydroxypropyl methacrylate, dimethylacrylamide, methacrylic acid, N-vinyl pyrrolidone, N-hydroxymethylacrylamide, acrylic acid, N,N-dimethylacrylamide, 2-hydroxypropyl acrylate, vinyl alcohol, 2-hydroxyethylacrylamide or methoxy polyethylene glycol methacrylate.

3. The preparation method according to claim 1, characterized in that: The main solvent and the secondary solvent are independently selected from ethyl acetate, ethylene carbonate, n-butanol, alcohol, xylene, toluene, N-methyl-2-pyrrolidone, cyclopentanone, cyclohexanone, methyl ethyl ketone, acetone, dimethylformamide, dimethyl sulfoxide or tetrahydrofuran.

4. The preparation method according to claim 1, characterized in that: The primary hydrophobic monomer, the secondary hydrophobic monomer and the tertiary hydrophobic monomer are independently selected from methyl methacrylate, ethyl methacrylate, 2-ethylhexyl methacrylate, butyl methacrylate, glyceryl methacrylate, ethoxyethyl methacrylate, styrene monomer, ethyl methacrylate, propyl methacrylate, butyl methacrylate, hexyl methacrylate, isobornyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate or isobutyl methacrylate.

5. The preparation method according to claim 1, characterized in that: The intensity of the ultraviolet light source is 500-1500mW / cm 2 , the ultraviolet wavelength is 330-395nm.

6. The preparation method according to claim 1, characterized in that: In step S3, the inhibitor is selected from 4-hydroxy-TEMPO, butylated hydroxytoluene, hydroquinone, hydroquinone monomethyl ether, tert-butylcatechol, phenothiazine or benzoquinone; the adhesion promoter is selected from hexamethylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, methacryloyloxyethyl isocyanate, tetramethylene diisocyanate, 2,4-toluene diisocyanate or methacryloyloxyethyl isocyanate.

7. The preparation method according to claim 1, characterized in that: The pigment is selected from ferric oxide, cadmium sulfide, cadmium selenide, lead tetroxide or organic pigment; the organic pigment is selected from perylene red or anthraquinone red.

8. The preparation method according to claim 1, characterized in that: The photoinitiator, the primary photoinitiator and the auxiliary photoinitiator are independently selected from benzoin derivatives, acylphosphine oxides, hydroxyalkyl phenones or benzyl ketals.

9. A contact lens ink resin prepared by the preparation method according to any one of claims 1 to 8.

10. The use of the contact lens ink resin according to claim 9, characterized in that: The contact lens ink resin is printed on a plastic surface to prepare a contact lens.

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