Self-hydrogen-supplying chalcone photoinitiator and application thereof in preparation of white photosensitive ink
By using a self-hydrogen-supplying chalcone photoinitiator, the problems of difficult curing, yellowing, and reduced reflectivity of white photosensitive inks in LED applications have been solved, achieving efficient deep curing and high reflectivity, making it suitable for industrial production.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- HEFEI UNIV OF TECH
- Filing Date
- 2024-01-02
- Publication Date
- 2026-08-04
AI Technical Summary
Existing white photosensitive inks have problems such as difficulty in curing, yellowing, and reduced reflectivity in LED applications. In particular, insufficient light absorption in the long-wavelength ultraviolet and visible light regions and incomplete curing of thick coatings lead to wrinkling of the film surface. In addition, commonly used photoinitiators have problems such as dark color, odor, and migration toxicity.
The self-hydrogen-supplying chalcone photoinitiator has alkylamino end groups, which have good long-wavelength light absorption performance and photobleaching properties. It avoids the problems of dark color and odor of commonly used photoinitiators, and provides self-hydrogen supply through the tertiary amine structure, thereby improving the deep curing efficiency and reflectivity.
It achieves excellent light absorption in the long-wavelength ultraviolet and visible light regions, ensuring deep curing of thick films, avoiding yellowing, reducing the amount of photoinitiator, improving reflectivity and reducing odor and toxicity, making it suitable for industrial production.
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Figure CN117843507B_ABST
Abstract
Description
Technical Field
[0001] This invention pertains to the synthesis of electronic chemicals and their application in photosensitive materials, specifically relating to a self-hydrogen-donating chalcone photoinitiator and its application in the preparation of white photosensitive inks. Background Technology
[0002] LED products have advantages such as energy saving, reliability, and long lifespan, and have been widely used. With the continuous improvement of the integration of LED devices, the requirements for the temperature resistance of materials for LED lamp beads, such as heat dissipation and circuit soldering, are increasing. This has led to increasingly higher requirements for the white photosensitive ink (photosensitive ink) required for LEDs and miniLEDs, in terms of resistance to yellowing and high reflectivity.
[0003] White photosensitive inks used for LEDs face the challenge of curing. Firstly, the high reflectivity required for white photosensitive inks, typically exceeding 90%, means less light is available to trigger the curing reaction. This necessitates photoinitiators with good light absorption in the long-wavelength ultraviolet and even visible light ranges. However, when the absorption wavelength of the photoinitiator exceeds 400nm, its own color deepens due to absorption of the blue end of visible light, leading to discoloration in the white photosensitive ink. Commonly used photoinitiators such as thioxanthones and titanocenes exhibit this problem. Secondly, white photosensitive ink coatings are relatively thick, typically reaching 50–60μm. Insufficient curing depth can cause wrinkling of the film surface. Furthermore, long-term light radiation from LEDs, the heat emitted, and environmental oxidation can all cause yellowing of the material, further reducing the reflectivity of the white photosensitive ink coating. Summary of the Invention
[0004] To address the contradiction between improving reflectivity and achieving deep curing in existing technologies, this invention provides a self-hydrogen-donating chalcone photoinitiator and its application in the preparation of white photosensitive inks. This invention utilizes a methylamino-terminated chalcone photoinitiator with self-hydrogen-donating properties. First, this photoinitiator exhibits good light absorption in the long-wavelength ultraviolet and visible light regions, improving the deep curing performance of the ink. Second, it possesses excellent photobleaching properties, solving the problem of existing long-wavelength photoinitiators such as thioxanthones and dicaprocene photoinitiators having darker colors and causing yellowing of the product when left in the ink. Third, the tertiary amine structure contained in this photoinitiator provides self-hydrogen donation, avoiding the odor, migration toxicity, and yellowing issues caused by the need for external co-initiator amines in hydrogen-extracting photoinitiators such as thioxanthones. Furthermore, this initiator exhibits high initiation activity, requires only a small amount, can be used for thick films, and is simple to synthesize, inexpensive, and easy to purify, making it suitable for industrial production.
[0005] The present invention relates to a self-hydrogen-donating chalcone photoinitiator, wherein the terminal group of the chalcone is an alkylamino group, and the general structural formula is shown below:
[0006]
[0007] In the above general formula, R1 is selected from dimethylamino, diethylamino, or morpholino; R2 is selected from H, methyl, or methoxy; R3 is selected from H or methyl; R4 is selected from H, methyl, hydroxyl, or methoxy; and R5 is selected from H, methyl, ethyl, methoxy, or ethoxy.
[0008] The self-hydrogen-supplying chalcone photoinitiator of this invention is prepared using the following process:
[0009] One part of a terephthalaldehyde compound was mixed with 2-10 parts of NaOH and water until homogeneous. The reaction temperature was controlled at 20-50℃ using a water bath. One to three parts of alkylaminoacetophenone were added in batches, and the mixture was stirred in a water bath for 2-12 hours. The mixture was then filtered, dried, and the crude product was washed with a 1:3 volume ratio alcohol-water mixed solvent and recrystallized to obtain the chalcone photoinitiator with an alkylamino end group. The alcohol in the alcohol-water mixed solvent was selected from methanol and ethanol.
[0010] The alkylaminoacetophenone is selected from one of 4'-dimethylaminoacetophenone, p-diethylaminoacetophenone, 4-morpholinylacetophenone, 1-[4-(dimethylamino)-3-methylphenyl]acetophenone, 1-[4-(dimethylamino)-2,6-dimethylphenyl]acetophenone, 1-[4-(dimethylamino)-2-hydroxyphenyl]acetophenone, and 1-[4-(dimethylamino)-2,5-dimethoxyphenyl]acetophenone; the terephthalaldehyde compound is selected from one of terephthalaldehyde, 2,5-dimethylterephthalaldehyde, 2,5-diethylterephthalaldehyde, 2,5-dimethoxyterephthalaldehyde, and 2,5-diethoxyterephthalaldehyde.
[0011] White photosensitive ink was prepared using the self-hydrogen-supplying chalcone photoinitiator of this invention, and the components were configured in the following proportions by mass:
[0012] The composition includes 25-50 parts of alkali-soluble acrylic resin, 1-20 parts of epoxy resin, 10-20 parts of active photosensitive monomer, 0.1-0.5 parts of photoinitiator, 20-40 parts of rutile titanium dioxide, and 0.5-3 parts of additives.
[0013] The alkali-soluble acrylic resin is a photosensitive resin without a benzene ring structure, with an acid value ranging from 70 to 120 mg KOH / g, and is selected from one or more of polyester acrylate resin, pure acrylic resin, hydrogenated bisphenol A epoxy acrylate resin, hydrogenated bisphenol F epoxy acrylate resin, and hydrogenated biphenyl epoxy acrylate resin. All the above raw materials are commercially available.
[0014] The epoxy resin is one or more of the following: alicyclic epoxy resin without benzene rings, and triglycidyl isocyanate (TGIC). All of the above raw materials are commercially available.
[0015] The active photosensitive monomer is selected from one or more of 1,6-hexanediol diacrylate (HDDA), tripropylene glycol diacrylate (TPGDA), diethylene glycol diacrylate (DEGDA), polyethylene glycol diacrylate (PEGDA), trimethylolpropane triacrylate (TMPTA), ethoxylated trimethylolpropane triacrylate (EO-TMPTA), pentaerythritol triacrylate (PETA), ethoxylated pentaerythritol tetraacrylate (PPTTA), and dipentaerythritol hexaacrylate (DPHA). All of the above raw materials are commercially available.
[0016] The additives include 0.25 to 1 part wetting and dispersing agent, 0 to 1 part leveling agent, 0 to 0.5 part adhesion promoter, and 0.25 to 0.5 part defoamer.
[0017] The above raw material components are stirred and mixed evenly at room temperature, and then ground in a sand mill or three-roll mill until the fineness is less than 10μm.
[0018] This invention employs a chalcone-type photoinitiator with an alkylamino end group that exhibits high initiation activity, long-wavelength absorption conducive to deep curing, photobleaching properties, and self-hydrogen supply characteristics. Using a benzene-free resin and monomer material system and rutile titanium dioxide, a high-reflectivity white photosensitive ink suitable for thick films was obtained.
[0019] Compared with the prior art, the present invention has the following beneficial effects:
[0020] The chalcone photoinitiator with terminal amino groups provided by this invention and the white photosensitive ink prepared therefrom have the following characteristics: (1) The photoinitiator has excellent light absorption characteristics in the long-wavelength ultraviolet and visible light regions, and the molar extinction coefficient reaches the order of 10. 4 (1) It is conducive to deep curing and can cure thick film coatings; (2) The photoinitiator has significant photobleaching characteristics. After long-wavelength ultraviolet and visible light irradiation, the yellow photoinitiator turns white, avoiding the yellowing of white ink; (3) The photoinitiator has high initiation efficiency. Only a mass fraction of no more than 1% in the formula can achieve complete curing, which is far lower than the 3-8% photoinitiator used in existing white inks; (4) The photoinitiator has self-hydrogen supply characteristics. When used in ink, there is no need to add amine co-initiators, avoiding the toxicity, precipitation and yellowing of small molecule amines; (5) The prepared white ink has high reflectivity, which can reach 95%, while current general products are difficult to reach 90%. Attached Figure Description
[0021] Figure 1 The hydrogen nuclear magnetic resonance spectrum of the self-hydrogen-supplying chalcone photoinitiator in Example 1.
[0022] Figure 2 The UV-Vis absorption spectrum of the self-hydrogen-supplying chalcone photoinitiator in Example 1.
[0023] Figure 3 The double bond conversion rate of the self-hydrogen-supplying chalcone photoinitiator in Example 1 to the active photosensitive monomer TPGDA is shown in the figure. Detailed Implementation
[0024] The present invention will be further illustrated by the following non-limiting embodiments.
[0025] Example 1: Preparation of self-hydrogen-donating chalcone photoinitiators
[0026] One part of terephthalaldehyde and two parts of NaOH were mixed evenly with water. The reaction temperature was controlled at 40℃ using a water bath. Two parts of 4'-dimethylaminoacetophenone were added in batches, and the mixture was stirred in a water bath for 6 hours. The mixture was then filtered, dried, and the crude product was washed with a 1:3 volume ratio of alcohol to water and recrystallized to obtain a chalcone photoinitiator with an alkylamino end group, namely 3,3'-(1,4-phenylene)bis[1-[4-(dimethylamino)phenyl]-2-propen-1-one], with a yield of 83%. Its structural formula is as follows:
[0027]
[0028] Its structure was characterized by proton NMR spectroscopy (see [reference]). Figure 1 It exhibits strong absorption in the long-wave ultraviolet to visible light region, with a maximum absorption wavelength of 400 nm and an absorption edge extending to 500 nm (see...). Figure 2 In the 365nm to 425nm wavelength range, the molar extinction coefficient can reach 2 to 3 × 10⁻⁶. 4 (See Table 1). At a dosage of only 0.05%, the double bond conversion rate of the active photosensitizing monomer TPGDA can reach over 90% (see Table 1). Figure 3 ).
[0029] Table 1. UV absorption performance data of the self-hydrogen-supplying chalcone photoinitiator in Example 1.
[0030] <![CDATA[λ max ]]> <![CDATA[ε max (M -1 cm -1 )]]> <![CDATA[ε 365 (M -1 cm -1 )]]> <![CDATA[ε 385 (M -1 cm -1 )]]> <![CDATA[ε 405 (M -1 cm -1 )]]> <![CDATA[ε 425 (M -1 cm -1 )]]> 400 <![CDATA[2.9×10 4 ]]> <![CDATA[1.80×10 4 ]]> <![CDATA[2.76×10 4 ]]> <![CDATA[2.86×10 4 ]]> <![CDATA[2.22×10 4 ]]>
[0031] Example 2: Preparation of self-hydrogen-supplying chalcone photoinitiators
[0032] One part of terephthalaldehyde and four parts of NaOH were mixed evenly with water. The reaction temperature was controlled at 50°C using a water bath. Three parts of p-diethylaminoacetophenone were added in batches, and the mixture was stirred in a water bath for 8 hours. The mixture was then filtered, dried, and the crude product was washed with a 1:3 volume ratio of alcohol to water and recrystallized to obtain a chalcone photoinitiator with an alkylamino end group, namely 3,3'-(1,4-phenylene)bis[1-[4-(diethylamino)phenyl]-2-propen-1-one], with a yield of 71%. Its structural formula is as follows:
[0033]
[0034] 1 H NMR (500MHz, CDCl3): δ H 8.11(1H,O=CC=CH-C,m),7.70(2H,HC-C(-C)=CH,m),7.63(3H,C-CH=C,m),6.83 (2H,NC-CH=C,m),3.61(2H,-CH2-N,m),3.30(2H,-CH2-N,m),1.22(6H,-CH3,m).
[0035] Example 3: Preparation of self-hydrogen-donating chalcone photoinitiators
[0036] One part of 2,5-dimethyl-3-phenylene terephthalaldehyde was mixed with five parts of NaOH and water until homogeneous. The reaction temperature was controlled at 35°C using a water bath. Two parts of 1-[4-(dimethylamino)-3-methylphenyl]acetone were added in batches, and the mixture was stirred in a water bath for 2 hours. The mixture was then filtered, dried, and the crude product was washed with a 1:3 volume ratio of alcohol to water and recrystallized to obtain a chalcone photoinitiator with an alkylamino end group, namely 3,3'-(2,5-dimethyl-1,4-phenylene)bis[1-[4-(dimethylamino)-3-methylphenyl]-2-propen-1-one], with a yield of 75%. Its structural formula is as follows:
[0037]
[0038] 1 H NMR (500MHz, CDCl3): δ H 8.10(1H,>C-CH=C,m),7.62(1H,C(=O)-C-CH=C(-CH3),m),7.55(2H,C(=O)-C=CH-C=C,m),7.35(1H,>CC=CH- C(=O),m),6.89(1H,-NC=CH-C,m),2.92(6H,-N-CH3,m),2.37(3H,C(-C)-C-CH3,m),2.31(3H,-NCC-CH3,m).
[0039] Example 4: Preparation of self-hydrogen-donating chalcone photoinitiators
[0040] One part of 2,5-diethyl-terephthalaldehyde and ten parts of NaOH were mixed evenly with water. The reaction temperature was controlled at 50°C using a water bath. One part of 1-[4-(dimethylamino)-2,6-dimethylphenyl]acetone was added in batches, and the mixture was stirred in a water bath for 12 hours. The mixture was then filtered, dried, and the crude product was washed with a 1:3 volume ratio of alcohol to water and recrystallized to obtain a chalcone photoinitiator with an alkylamino end group, namely 3,3'-(2,5-diethyl-1,4-phenylene)bis[1-[4-(dimethylamino)-2,6-dimethylphenyl]-2-propen-1-one], with a yield of 68%. Its structural formula is as follows:
[0041]
[0042] 1 H NMR (500MHz, CDCl3): δ H 8.18(1H,>C-CH=CC(=O),m),7.63(1H,CH-C(-C2H5),m),7.34(1H,CC=CH-C(=O)-C,m),6.60(2H,C(-N)=C H-C,m),2.93(6H,H3C-N-,m),2.63(2H,>C-CH2-CH3,m),2.36(6H,H3C-C<,m),1.32(3H,H3C-CH2-C<,m).
[0043] Example 5: Preparation of self-hydrogen-donating chalcone photoinitiators
[0044] One part of 2,5-diethoxy-2-phenylene glycol was mixed with two parts of NaOH and water until homogeneous. The reaction temperature was controlled at 25°C using a water bath. Two parts of 1-[4-(dimethylamino)-2-hydroxyphenyl]ethyl ketone were added in batches, and the mixture was stirred in a water bath for 6 hours. The mixture was then filtered, dried, and the crude product was washed with a 1:3 volume ratio of alcohol to water and recrystallized to obtain a chalcone photoinitiator with an alkylamino end group, namely 3,3'-(2,5-diethoxy-1,4-phenylene)bis[1-[4-(dimethylamino)-2-hydroxyphenyl]-2-propen-1-one], with a yield of 75%. Its structural formula is as follows:
[0045]
[0046] 1 H NMR (500MHz, CDCl3): δ H8.24(1H,>C-CH=C,m),7.45(3H,C-CH=C,m),6.83(1H,-OH,m),6.42(1H,-NC-CH=CC,m),6.38(1H,-NC=CH-C(-OH),m),4.04
[0047] (2H,CO-CH2-CH3,m),2.93(6H,-N-CH3,m),1.41(3H,CO-CH2-CH3,m).
[0048] Example 6: Preparation of self-hydrogen-donating chalcone photoinitiators
[0049] One part of 2,5-dimethoxy-2,5-phenylene ether was mixed with two parts of NaOH and water until homogeneous. The reaction temperature was controlled at 20°C using a water bath. Two parts of 1-[4-(dimethylamino)-2,5-dimethoxyphenyl]ethyl ketone were added in batches, and the mixture was stirred in a water bath for 4 hours. The mixture was then filtered, dried, and the crude product was washed with a 1:3 volume ratio of alcohol to water and recrystallized to obtain a chalcone photoinitiator with an alkylamino end group, namely 3,3'-(2,5-dimethoxy-1,4-phenylene)bis[1-[4-(dimethylamino)-2,5-dimethoxyphenyl]-2-propen-1-one], with a yield of 79%. Its structural formula is as follows:
[0050]
[0051] 1 H NMR (500MHz, CDCl3): δ H 7.91(1H,>C-CH=C,m),7.37(1H,C-CH=C(-O),m),7.30(1H,CC(=O)-CH=CC,m),7.20(1H,C(- O)=CH-CC(=O),m),6.44(1H,-NC=CH-C(-O),m),3.82(9H,CO-CH3,m),2.93(6H,H3C-N-,m).
[0052] Example 7: Preparation of self-hydrogen-donating chalcone photoinitiators
[0053] One part of terephthalaldehyde and four parts of NaOH were mixed evenly with water. The reaction temperature was controlled at 40℃ using a water bath. Two parts of 4-morpholinoacetophenone were added in batches, and the mixture was stirred in a water bath for 8 hours. The mixture was then filtered, dried, and the crude product was washed with a 1:3 volume ratio of alcohol to water and recrystallized to obtain a chalcone photoinitiator with an alkylamino end group, namely 3,3'-(1,4-phenylene)bis[1-(4-morpholinophenyl)-2-propen-1-one], with a yield of 75%. Its structural formula is as follows:
[0054]
[0055] 1 H NMR (500MHz, CDCl3): δ H 8.11(1H,CC(=O)-C=CH-C,m),7.67(5H,C-CH=C,m),6.87(2H,NC(=CH)-CH=C,m),3.79(4H,O-CH2-CN,m),3.49(2H,OC-CH2-N,m),3.34
[0056] (2H,N-CH2-CO,m).
[0057] Example 8:
[0058] Under room temperature and yellow light conditions, 15 parts of polyester acrylate, 20 parts of hydrogenated bisphenol A epoxy acrylate, 12 parts of alicyclic epoxy resin, 5 parts of EO-TMPTA, 12 parts of TPGDA, 2 parts of DPHA, 0.1 parts of 3,3'-(1,4-phenylene)bis[1-[4-(dimethylamino)phenyl]-2-propen-1-one], 20 parts of titanium dioxide, 0.25 parts of wetting and dispersing agent, 0.3 parts of leveling agent, and 0.25 parts of defoamer are stirred and mixed evenly in a sealed container, and then ground in a sand mill until the fineness is less than 10 μm. The resulting white photosensitive resin composition is stored in a light-proof container and can be used for high-reflectivity solder resist inks.
[0059] The white ink described above was used to prepare the corresponding coating through a roller coating process, and then exposed to a light source in the wavelength range of 405–425 nm with an exposure energy of 100–300 mJ / cm². 2 The sample was then developed in a 1% Na₂CO₃ solution, and finally treated at 150–200°C for 1 hour. The reflectance was measured to be 90% using a spectrophotometer.
[0060] Comparative Example 1:
[0061] The difference from Example 8 is that the photoinitiator used is 0.1 parts of ITX (2-isopropylthioxanthraquinone) and 0.2 parts of EDAB (ethyl 4-(dimethylamino)benzoate), and the prepared coating cannot be completely cured.
[0062] Example 9:
[0063] Under room temperature and yellow light conditions, 15 parts of pure acrylate, 25 parts of hydrogenated bisphenol F epoxy acrylate resin, 12 parts of alicyclic epoxy resin, 5 parts of TMPTA, 2 parts of TPGDA, 2 parts of PPTTA, 0.3 parts of 3,3'-(1,4-phenylene)bis[1-[4-(diethylamino)phenyl]-2-propen-1-one], 30 parts of titanium dioxide, 0.5 parts of wetting and dispersing agent, 0.3 parts of leveling agent, 0.3 parts of defoamer, and 0.3 parts of adhesion promoter were stirred and mixed evenly in a sealed container, and then ground in a sand mill until the fineness was less than 10 μm. The resulting white photosensitive resin composition was stored in a light-proof container and can be used for high-reflectivity solder resist inks.
[0064] The white ink described above was used to prepare the corresponding coating through a roller coating process, and then exposed to a light source in the wavelength range of 405–425 nm with an exposure energy of 100–300 mJ / cm². 2 The sample was then developed in a 1% Na₂CO₃ solution, and finally treated at 150–200°C for 1 hour. The reflectance was measured to be 92% using a spectrophotometer.
[0065] Comparative Example 2:
[0066] The difference from Example 9 is that the photoinitiator used is 0.5 parts of ITX (2-isopropylthioxanthraquinone) and 1 part of EDAB (ethyl 4-(dimethylamino)benzoate), and the reflectance of the prepared coating was measured to be 85%.
[0067] Example 10:
[0068] Under room temperature and yellow light conditions, 15 parts of pure acrylate, 35% hydrogenated bisphenol A epoxy acrylate, 12 parts of alicyclic epoxy resin, 8 parts of TGIC, 5 parts of EO-TMPTA, 5 parts of TPGDA, 5 parts of PETA, 5 parts of DPHA, 0.5 parts of 3,3'-(2,5-dimethoxy-1,4-phenylene)bis[1-[4-(dimethylamino)-2,5-dimethoxyphenyl]-2-propen-1-one], 40 parts of titanium dioxide, 1 part of wetting and dispersing agent, 0.5 parts of defoamer, and 0.5 parts of adhesion promoter were stirred and mixed evenly in a sealed container, and then ground in a sand mill until the fineness was less than 10 μm. The resulting white photosensitive resin composition was stored in a light-proof container and sealed. It can be used for high-reflectivity solder resist inks.
[0069] The white ink described above was used to prepare the corresponding coating through a roller coating process, and then exposed to a light source in the wavelength range of 405–425 nm with an exposure energy of 100–300 mJ / cm². 2 The sample was then developed in a 1% Na₂CO₃ solution, and finally treated at 150–200°C for 1 hour. The reflectance was measured to be 95% using a spectrophotometer.
[0070] Example 11:
[0071] Under room temperature and yellow light conditions, 15 parts of pure acrylate, 20 parts of hydrogenated biphenyl epoxy acrylate, 12 parts of TGIC, 5 parts of EO-TMPTA, 5 parts of TPGDA, 5 parts of PETA, 5 parts of DPHA, 0.4 parts of 3,3'-(2,5-dimethyl-1,4-phenylene)bis[1-[4-(dimethylamino)-3-methylphenyl]-2-propen-1-one], 25 parts of titanium dioxide, 0.5 parts of leveling agent, 0.3 parts of defoamer, and 0.3 parts of adhesion promoter were stirred and mixed evenly in a sealed container, and then ground in a sand mill until the fineness was less than 10 μm. The resulting white photosensitive resin composition was stored in a light-proof container and sealed. It can be used for high-reflectivity solder resist inks.
[0072] The white ink described above was used to prepare the corresponding coating through a roller coating process, and then exposed to a light source in the wavelength range of 405–425 nm with an exposure energy of 100–300 mJ / cm². 2 The sample was then developed in a 1% Na₂CO₃ solution, and finally treated at 150–200°C for 1 hour. The reflectance was measured to be 93% using a spectrophotometer.
[0073] Example 12:
[0074] Under room temperature and yellow light conditions, 15 parts of pure acrylate, 25 parts of hydrogenated bisphenol F epoxy acrylate resin, 12 parts of alicyclic epoxy resin, 5 parts of TMPTA, 2 parts of TPGDA, 2 parts of PPTTA, 0.3 parts of 3,3'-(2,5-diethyl-1,4-phenylene)bis[1-[4-(dimethylamino)-2,6-dimethylphenyl]-2-propen-1-one], 30 parts of titanium dioxide, 0.5 parts of wetting and dispersing agent, 0.3 parts of leveling agent, 0.3 parts of defoamer, and 0.3 parts of adhesion promoter were stirred and mixed evenly in a sealed container, and then ground in a sand mill until the fineness was less than 10 μm. The resulting white photosensitive resin composition was stored in a light-proof container and can be used for high-reflectivity solder resist inks.
[0075] The white ink described above was used to prepare the corresponding coating through a roller coating process, and then exposed to a light source in the wavelength range of 405–425 nm with an exposure energy of 100–300 mJ / cm². 2 The sample was then developed in a 1% Na₂CO₃ solution, and finally treated at 150–200°C for 1 hour. The reflectance was measured to be 94% using a spectrophotometer.
[0076] Example 13:
[0077] Under room temperature and yellow light conditions, 15 parts of pure acrylate, 25 parts of hydrogenated bisphenol F epoxy acrylate resin, 12 parts of alicyclic epoxy resin, 5 parts of TMPTA, 2 parts of TPGDA, 2 parts of PPTTA, 0.3 parts of 3,3'-(2,5-diethoxy-1,4-phenylene)bis[1-[4-(dimethylamino)-2-hydroxyphenyl]-2-propen-1-one], 30 parts of titanium dioxide, 0.5 parts of wetting and dispersing agent, 0.3 parts of leveling agent, and 0.3 parts of defoamer were stirred and mixed evenly in a sealed container, and then ground in a sand mill until the fineness was less than 10 μm. The resulting white photosensitive resin composition was stored in a light-proof container and sealed. It can be used for high-reflectivity solder resist inks.
[0078] The white ink described above was used to prepare the corresponding coating through a roller coating process, and then exposed to a light source in the wavelength range of 405–425 nm with an exposure energy of 100–300 mJ / cm². 2 The sample was then developed in a 1% Na₂CO₃ solution, and finally treated at 150–200°C for 1 hour. The reflectance was measured to be 93% using a spectrophotometer.
[0079] Example 14:
[0080] Under room temperature and yellow light conditions, 10 parts of pure acrylate, 20 parts of hydrogenated bisphenol F epoxy acrylate resin, 12 parts of alicyclic epoxy resin, 5 parts of HDDA, 5 parts of PEGDA, 2 parts of PPTTA, 0.3 parts of 3,3'-(1,4-phenylene)bis[1-(4-morpholinylphenyl)-2-propen-1-one], 20 parts of titanium dioxide, 0.5 parts of wetting and dispersing agent, 0.3 parts of leveling agent, 0.3 parts of defoamer, and 0.3 parts of adhesion promoter were stirred and mixed evenly in a sealed container, and then ground in a sand mill until the fineness was less than 10 μm. The resulting white photosensitive resin composition was stored in a light-proof container and can be used for high-reflectivity solder resist inks.
[0081] The white ink described above was used to prepare the corresponding coating through a roller coating process, and then exposed to a light source in the wavelength range of 405–425 nm with an exposure energy of 100–300 mJ / cm². 2 The sample was then developed in a 1% Na₂CO₃ solution, and finally treated at 150–200°C for 1 hour. The reflectance was measured to be 90% using a spectrophotometer.
Claims
1. The use of a self-hydrogen-donating chalcone photoinitiator in the preparation of a white photogum, characterized in that The general structural formula of the self-hydrogen-supplying chalcone photoinitiator is shown below: ； In the above general formula, R1 is selected from dimethylamino, diethylamino, or morpholino; R2 is selected from H, methyl, or methoxy; R3 is selected from H or methyl; R4 is selected from H, methyl, hydroxyl, or methoxy; and R5 is selected from H, methyl, ethyl, methoxy, or ethoxy. The components of the white photosensitive ink are composed of the following parts by mass: The ingredients are: 25-50 parts alkali-soluble acrylic resin, 1-20 parts epoxy resin, 10-20 parts active photosensitive monomer, 0.1-0.5 parts photoinitiator, 20-40 parts rutile titanium dioxide, and 0.5-3 parts additives.
2. Use according to claim 1, characterized in that The self-hydrogen-supplying chalcone photoinitiator is prepared by a method comprising the following steps: According to the mass fraction, 1 part of terephthalaldehyde compound and 2-10 parts of NaOH are mixed evenly with water. The reaction temperature is controlled at 20-50℃ in a water bath. 1-3 parts of alkylaminoacetophenone are added in batches. The mixture is stirred in a water bath for 2-12 hours. After filtration and drying, the crude product is recrystallized to obtain chalcone photoinitiators with alkylamino end groups. The alkylaminoacetophenone is selected from one of 4′-dimethylaminoacetophenone, p-diethylaminoacetophenone, 4-morpholinylacetophenone, 1-[4-(dimethylamino)-3-methylphenyl]acetophenone, 1-[4-(dimethylamino)-2,6-dimethylphenyl]acetophenone, 1-[4-(dimethylamino)-2-hydroxyphenyl]acetophenone, and 1-[4-(dimethylamino)-2,5-dimethoxyphenyl]acetophenone; the terephthalaldehyde compound is selected from one of terephthalaldehyde, 2,5-dimethylterephthalaldehyde, 2,5-diethylterephthalaldehyde, 2,5-dimethoxyterephthalaldehyde, and 2,5-diethoxyterephthalaldehyde.
3. The application according to claim 1, characterized in that: The alkali-soluble acrylic resin is a photosensitive resin without a benzene ring structure, with an acid value ranging from 70 to 120 mg KOH / g, and is selected from one or more of polyester acrylate resin, pure acrylic resin, hydrogenated bisphenol A epoxy acrylate resin, hydrogenated bisphenol F epoxy acrylate resin, and hydrogenated biphenyl epoxy acrylate resin.
4. The application according to claim 1, characterized in that: The epoxy resin is one or more of the following: alicyclic epoxy resin without benzene rings and triglycidyl isocyanate.
5. The application according to claim 1, characterized in that: The active photosensitive monomer is selected from one or more of 1,6-hexanediol diacrylate, tripropylene glycol diacrylate, diethylene glycol diacrylate, polyethylene glycol diacrylate, trimethylolpropane triacrylate, ethoxylated trimethylolpropane triacrylate, pentaerythritol triacrylate, ethoxylated pentaerythritol tetraacrylate, and dipentaerythritol hexaacrylate.
6. The application according to claim 1, characterized in that: The additives include 0.25-1 part wetting and dispersing agent, 0-1 part leveling agent, 0-0.5 part adhesion promoter, and 0.25-0.5 part defoamer.
7. The application according to claim 1, characterized in that: All raw material components are stirred and mixed evenly at room temperature, and then ground in a sand mill or three-roll mill until the fineness is less than 10 μm.