Light-absorbing compounds, materials, methods of preparation and uses
By doping transparent resin with isobutyl-modified light-absorbing compounds, the problem of narrow-band high absorption and high transmittance of filter materials in the 420nm wavelength band is solved, and the compatibility and thermal stability with optical resins are enhanced, making it suitable for miniaturized and integrated optical systems.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- FUYANG XINYIHUA PHARM TECH CO LTD
- Filing Date
- 2026-05-29
- Publication Date
- 2026-07-31
AI Technical Summary
Existing filter materials struggle to achieve narrowband high absorption in the 420nm band while maintaining high transmittance in the bands below 360nm and above 440nm. Furthermore, they are difficult to be well-compatible with optical resins and have insufficient processing stability.
By using isobutyl-modified light-absorbing compounds and doping them into transparent resins, a high absorption rate in the 420nm band is achieved, while maintaining high transmittance in the bands below 360nm and above 440nm. This also improves compatibility and thermal stability with non-polar or weakly polar optical resins.
It achieves high absorption performance at low addition concentrations, reduces bioirritation, improves compatibility and thermal stability with optical resins, and broadens the processing temperature range.
Smart Images
Figure CN122483012A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of optical materials technology, specifically relating to a light-absorbing compound, material, preparation method, and application. Background Technology
[0002] The 390–430 nm wavelength range (especially around 420 nm) has important applications in biological detection, chemical analysis, laser protection, and optical sensing. For example, in colorimetric determination or fluorescence analysis of water quality indicators such as ammonia nitrogen and hexavalent chromium, 420 nm is the detection wavelength for characteristic colorimetric reactions. All of these applications require the precise extraction of signal light around 420 nm from broadband light sources or complex background light, while simultaneously suppressing interference from ultraviolet (<360 nm) and blue-green light (>440 nm).
[0003] In existing technologies, narrowband filtering mainly relies on interferometric multilayer dielectric film filters. These filters create bandpass or notch effects by stacking dozens of alternating high / low refractive index thin films. While they offer the advantage of high wavelength selectivity, they suffer from drawbacks such as complex fabrication processes, high costs, and strong angle dependence. Furthermore, interferometric filters are difficult to conformally integrate on curved or flexible substrates, limiting their application in miniaturized and integrated optical systems.
[0004] Absorbent light-filtering materials typically achieve specific wavelength cutoff by doping transparent resins with light-absorbing agents, offering advantages such as low cost, angle independence, and ease of processing and molding. However, existing absorbent materials are mostly designed for broadband ultraviolet (200–380 nm) protection or broadband blue light (400–500 nm) blocking, making it difficult to achieve narrowband high absorption (transmittance <6%) near 420 nm while maintaining high transmittance (>85%) in the wavelength range below 360 nm and above 440 nm. Therefore, developing a novel light-absorbing material with highly selective absorption in the 420 nm band and ease of composite with optical resins has significant technological value and broad application prospects. Summary of the Invention
[0005] To address the shortcomings of existing technologies, one objective of this invention is to provide a light-absorbing material, including... .
[0006] The core component of the light-absorbing material provided in this application is: This compound exhibits high absorption in the 420nm band, but high transmittance in bands below 360nm and above 440nm.
[0007] Furthermore, in the light-absorbing material provided in this application, the introduction of isobutyl groups enhances the compatibility of the compound with non-polar or weakly polar optical resins (such as polycarbonate), effectively suppressing precipitation during use or aging, thereby maintaining stable light absorption performance at lower addition concentrations, balancing economy and reliability. In addition, the steric hindrance effect of isobutyl groups improves the thermal stability of the compound during high-temperature melt processing (such as injection molding and extrusion), reducing the risk of deterioration due to thermally induced side reactions, thus broadening the applicable processing temperature range.
[0008] Preferably, the light-absorbing material comprises 20ppm to 100ppm of The light-absorbing material has a light absorption rate of ≥94% in the wavelength range of 395~430nm.
[0009] Preferably, the light-absorbing material comprises 20ppm to 100ppm of The light absorption rate in the wavelength range of 395~420nm is ≥98.5%.
[0010] Preferably, the material comprises 20ppm to 100ppm of The light-absorbing material has a light transmittance of ≥28.8% in the range of 440nm~500nm, a light transmittance of ≥66.9% in the range of 450nm~500nm, and a light transmittance of ≥90.6% in the range of 460nm~500nm.
[0011] Preferably, in the light-absorbing material, the amount of the light-absorbing compound represented by formula (I) added is ≥20ppm, such as 21ppm, 25ppm, 32ppm, 38ppm, 45ppm, 54ppm, 60ppm, 67ppm, 76ppm, 86ppm, 95ppm, 120ppm, 150ppm, 168ppm, 177ppm, 195ppm, 205ppm, 220ppm, etc., preferably 20ppm~200ppm, more preferably 20ppm~80ppm.
[0012] The light-absorbing material provided in this application can achieve low-dose addition of light-absorbing compounds. This application does not specifically limit the substrate material of the light-absorbing material. Typical but non-limiting materials include polycarbonate (PC), polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), polystyrene (PS), polypropylene (PP), polyethylene (PE), polyamide (PA), polyvinyl chloride (PVC), polyurethane (PU), etc. Preferred substrates are those with good compatibility with the light-absorbing material, such as polycarbonate (PC).
[0013] The second objective of this application is to provide a light-absorbing compound with the following structure: The light-absorbing compound, at a concentration of 20 ppm, exhibits a light absorption of ≥94% at wavelengths of 395–430 nm.
[0014] The light-absorbing compound described in this application can achieve high absorption with low addition amount, and also has the characteristics of low irritation, high resin compatibility and high stability.
[0015] The third objective of this application is to provide a method for preparing a light-absorbing compound, comprising the following steps:
[0016] (1) Using 4-(4-morpholine)benzaldehyde and isobutyl cyanoacetate as raw materials and triethylbenzylammonium chloride as catalyst, the raw materials and catalyst were added to toluene, stirred and replaced with argon gas.
[0017] (2) Heat the reaction system to the point where the reaction liquid is refluxed for 1-3 hours, then cool down to end the reaction and post-process to obtain a light-absorbing compound with the structure of formula (I).
[0018] Preferably, the molar ratio of 4-(4-morpholine)benzaldehyde and isobutyl cyanoacetate is 1:0.9 to 1:1.1.
[0019] Preferably, the triethylbenzylammonium chloride is mixed with 4-(4-morpholine)benzaldehyde in a ratio of 1.8:1 to 2.1:1.
[0020] Preferably, the volume of toluene added is 4.8~5.5 mL / g of the mass of 4-(4-morpholine)benzaldehyde.
[0021] Preferably, the post-processing includes the following steps:
[0022] The reaction system was cooled until a small amount of solid precipitated. Dichloromethane and pure water were added and stirred. The mixture was allowed to stand and separate into layers. The organic phase was taken, washed and dried, and DCM was removed by rotary evaporation. Methanol was added to the material to dissolve it, and the mixture was filtered. The filter residue was a light-absorbing compound.
[0023] The fourth objective of this application is to provide a use of the light-absorbing material described in the first objective or the light-absorbing compound described in the second objective, wherein the light-absorbing material or light-absorbing compound is used as a filter material, preferably as any one or a combination of at least two of filter elements and optical detectors.
[0024] The fifth objective of this application is to provide a light-absorbing material, wherein the light-absorbing material is added with the light-absorbing material described in the first objective or the light-absorbing compound described in the second objective.
[0025] Preferably, the filter material contains at least 20 ppm of a light-absorbing compound having the structure of formula (I).
[0026] Compared with the prior art, this application has the following beneficial effects:
[0027] The core components of the light-absorbing material provided in this application The light-absorbing compound has light absorption of 390~420nm, and at a concentration of 20ppm, it has a narrow-band strong absorption of ≥94% for light with wavelengths of 395~430nm; it also has low bioirritation, high compatibility with non-polar or weakly polar optical resins, and high thermal stability. Attached Figure Description
[0028] Figure 1 The image shows the HPLC chromatogram of the reaction system sampled and analyzed after 1 hour of reaction in step 2 of Example 1.
[0029] Figure 2 The image shows the HPLC chromatogram of the reaction system sampled and analyzed after 2 hours of reaction in step 2 of Example 1.
[0030] Figure 3 This is an HPLC chromatogram of the filtrate after post-treatment in step 3 of Example 1.
[0031] Figure 4 This is an HPLC chromatogram of the filter residue after post-treatment in step 3 of Example 1.
[0032] Figure 5 NMR spectrum of the light-absorbing compound provided in Example 1;
[0033] Figure 6 A photograph of the light-absorbing compound provided in Example 1;
[0034] Figure 7 The full-band spectral scan curve of the light-absorbing compound obtained in Example 1 is shown in the range of 300 nm to 700 nm. Detailed Implementation
[0035] The technical solution of the present invention will be further explained and described below with reference to specific embodiments. However, it should be noted that the specific embodiments are only a specific implementation and explanation of the essence of the technical solution of the present invention, and should not be construed as a limitation on the scope of protection of the present invention.
[0036] The reagents and instruments used in the examples are all commercially available, and the detection methods are conventional methods well known in the art.
[0037] Example 1
[0038] A method for preparing isobutyl(E)-2-cyano-3-(4-morpholinophenyl)acrylate includes the following steps:
[0039] (1) Add 2g of 4-(4-morpholine)benzaldehyde, 1.42g of isobutyl cyanoacetate and 4.6g of triethylbenzylammonium chloride to 10mL of toluene, stir and purge with argon;
[0040] (2) After the addition of materials is complete, heat the reaction system in an oil bath at 120°C. Reflux the reaction solution for 2 hours, then cool it down to end the reaction. Take a sample after reflux for 1 hour for high-performance liquid chromatography (HPLC) detection. The results are as follows: Figure 1 ( Figure 1 The HPLC chromatogram of the reaction system after step 2 of Example 1, taken after 1 hour of reaction, is shown below; after reflux for 2 hours, samples were taken for HPLC analysis, and the results are as follows. Figure 2 ( Figure 2 The HPLC chromatogram of the reaction system sampled and analyzed after 2 hours of reaction in Step 2 of Example 1 is shown below; from Figure 1 It can be seen that the peak area normalization ratio of the raw material (4-morpholinobenzaldehyde) is approximately 11%, while the peak area normalization ratio of the product is approximately 74%. Figure 1 It can be seen that the normalized peak area of raw materials accounts for approximately 8.3%, while the normalized peak area of products accounts for approximately 89%.
[0041] (3) Cool the reaction system until a small amount of solid precipitates (about 50~60℃), add 20mL of dichloromethane and 20mL of pure water, stir, let stand to separate the layers, take the organic phase, wash twice with 40mL of pure water, add anhydrous magnesium sulfate and dry, remove DCM by rotary evaporation, add 10mL of methanol to the material to dissolve, filter, the filter residue is light-absorbing compound. The filtered filtrate was analyzed by high-performance liquid chromatography (HPLC), and the results are as follows: Figure 3 ( Figure 3 The HPLC chromatogram of the filtrate after post-treatment in step 3 of Example 1 is shown below. The filtered residue was analyzed by high-performance liquid chromatography (HPLC), and the results are as follows: Figure 4 ( Figure 4 The HPLC chromatogram of the filter residue after post-treatment in step 3 of Example 1 is shown below; from Figure 4 It can be seen that the purity of the light-absorbing compound in the filter residue is 99.67%, and the yield is 64%.
[0042] Figure 5 The NMR spectra of the light-absorbing compounds are given. Figure 5 The NMR results were 1H-NMR (deuterated chloroform), with chemical shifts of 1.04 (d, 6H), 2.10 (m, 1H), 3.42 (t, 4H), 3.89 (t, 4H), 4.11 (d, 2H), 6.93 (d, 2H), 8.00 (d, 2H), and 8.13 (s, 1H), which are consistent with... The analysis results.
[0043] Figure 6 A photograph of the light-absorbing compound is provided, showing that it is a yellow powder.
[0044] Comparative Example
[0045] The preparation method of ethyl (E)-2-cyano-3-(4-morpholinylphenyl)acrylate differs from that in Example 1 only in that 1.42 g of isobutyl cyanoacetate is replaced with 1.13 g of ethyl cyanoacetate. The filter residue obtained by final filtration was determined to be a light-absorbing compound. Calculations showed that the purity of the light-absorbing compound was 99.13%, and the yield was 58%.
[0046] Performance testing:
[0047] (1) Light absorption:
[0048] The light-absorbing compounds obtained in Example 1 and the comparative example were dissolved in tetrahydrofuran at a concentration of 20 ppm and subjected to illumination from 395 nm to 420 nm. The light transmittance of each wavelength band was tested. The full-band spectral scanning curve of the light-absorbing compound obtained in Example 1 from 300 nm to 700 nm is shown below. Figure 7 As shown, the test results are shown in Table 1.
[0049] Table 1
[0050]
[0051] As can be seen from Table 1, the light-absorbing compound provided in this application can achieve high light absorption performance at extremely low concentrations. In particular, in the range of 395~430nm, the light absorption can be above 98%, while the light absorption drops sharply at 440nm and above. The light transmittance is higher than 28.8%, and the light transmittance continues to increase with the increase of wavelength.
[0052] (2) Compatibility test:
[0053] Bisphenol A type polycarbonate (PC) with a weight average molecular weight of 25,000-30,000 was used as the base resin. 20 ppm of the light-absorbing material from Example 1 and the comparative example were added to the sample, respectively. The sample was melt-blended by twin-screw extrusion (260-280°C, 2-3 min) and then pressed by a flat vulcanizing machine to obtain Sample 1 and Sample 2. 50 ppm of the light-absorbing material from Example 1 and the comparative example were added to the sample, respectively. The sample was melt-blended by twin-screw extrusion (260-280°C, 2-3 min) and then pressed by a flat vulcanizing machine to obtain Sample 3 and Sample 4.
[0054] High temperature and high humidity aging: The sample was placed at 85°C and 85% humidity, and the haze was tested at 0h and 500h (ASTM D1003A method).
[0055] Thermal precipitation: The sample was baked at 120°C for 72 hours, the haze was measured (ASTM D1003), and the presence or absence of crystal precipitation was observed.
[0056] The test results are shown in Table 2.
[0057] Table 2
[0058]
[0059] As can be seen from Table 2, and Although the structures are the same, It exhibits high absorbance (≥94%) at low concentrations (e.g., 20 ppm) and narrow-band absorption characteristics. Furthermore, when added to the base resin, It has better compatibility and better stability.
[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.
Claims
1. A light-absorbing material, characterized in that, The material includes light-absorbing compounds. .
2. The light-absorbing material as described in claim 1, characterized in that, The light-absorbing material comprises 20 ppm to 100 ppm of light-absorbing compounds. The light-absorbing material has a light absorption rate of ≥94% in the wavelength range of 395~430nm; Preferably, the light-absorbing material comprises 20 ppm to 100 ppm of light-absorbing compounds. The light absorption rate in the wavelength range of 395~420nm is ≥98.5%.
3. The light-absorbing material as described in claim 1 or 2, characterized in that, The material includes 20ppm to 100ppm of light-absorbing compounds. The light-absorbing material has a light transmittance of ≥28.8% in the range of 440nm~500nm, a light transmittance of ≥66.9% in the range of 450nm~500nm, and a light transmittance of ≥90.6% in the range of 460nm~500nm.
4. The light-absorbing material according to any one of claims 1 to 3, characterized in that, In the light-absorbing material, the amount of light-absorbing compound added is ≥20ppm, preferably 20ppm~200ppm, and more preferably 20ppm~80ppm.
5. A light-absorbing compound, characterized in that, The structure of the light-absorbing compound is as follows: The light-absorbing compound, at a concentration of 20 ppm, exhibits a light absorption of ≥94% at wavelengths of 395–430 nm.
6. A method for preparing the light-absorbing compound as described in claim 5, characterized in that, The preparation method includes the following steps: (1) Using 4-(4-morpholine)benzaldehyde and isobutyl cyanoacetate as raw materials and triethylbenzylammonium chloride as catalyst, the raw materials and catalyst were added to toluene, stirred and replaced with argon gas; (2) Heat the reaction system to the point where the reaction liquid is refluxed for 1-3 hours, then cool down to end the reaction and proceed with post-treatment to obtain the light-absorbing compound.
7. The preparation method according to claim 6, characterized in that, The molar ratio of 4-(4-morpholine)benzaldehyde to isobutyl cyanoacetate is 1:0.9 to 1:1.1; Preferably, the ratio of triethylbenzylammonium chloride to 4-(4-morpholine)benzaldehyde is 1.8:1 to 2.1:1; Preferably, the volume of toluene added is 4.8~5.5 mL / g of the mass of 4-(4-morpholine)benzaldehyde.
8. The preparation method according to claim 6 or 7, characterized in that, The post-processing includes the following steps: The reaction system was cooled until a small amount of solid precipitated. Dichloromethane and pure water were added and stirred. The mixture was allowed to stand and separate into layers. The organic phase was taken, washed and dried, and DCM was removed by rotary evaporation. Methanol was added to the material to dissolve it, and the mixture was filtered. The filter residue was a light-absorbing compound.
9. Use of a light-absorbing material as described in any one of claims 1 to 4 or a light-absorbing compound as described in claim 5, characterized in that, The light-absorbing material or light-absorbing compound is used as a filter material, preferably as any one or a combination of at least two of the filter elements and optical detectors.
10. A light-filtering material, characterized in that, The filter material is added with a light-absorbing material as described in any one of claims 1 to 4 or a light-absorbing compound as described in claim 5; Preferably, the filter material contains at least 20 ppm of the light-absorbing compound of claim 5, and more preferably 20 ppm to 80 ppm of the light-absorbing compound of claim 5.