Screen printing coating based on mixing of metal screen printing solvent and boron powder as well as preparation method and application of screen printing coating
By using screen printing technology that mixes metal screen printing solvent with boron powder, the problems of complex equipment, low efficiency, and poor consistency in the manufacturing of boron-coated detector coatings have been solved. This technology enables precise control of coating thickness and achieves high purity and adhesion, making it suitable for the production of thin coatings for neutron detectors and other inorganic materials.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHINA NUCLEAR CONTROL SYST ENG
- Filing Date
- 2026-02-10
- Publication Date
- 2026-05-19
AI Technical Summary
Existing boron-coated detectors have complex coating manufacturing equipment, low production efficiency, poor coating consistency, and high impurity content, making it difficult to achieve precise thickness control, which affects neutron sensitivity and application scenarios.
A coating is prepared by mixing a metal screen printing solvent with boron powder and using screen printing technology. The coating thickness is controlled and the impurity content is reduced by combining low-temperature hot air drying and high-temperature curing, thus forming a strong micron-level coating.
It achieves precise control of coating thickness, improves coating adhesion and purity, adapts to complex environments, simplifies the production process, improves production efficiency, and meets the requirements of demanding application scenarios.
Smart Images
Figure CN122058652A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of inorganic material coating technology, specifically relating to a screen printing coating based on a mixture of metal screen printing solvent and boron powder, its preparation method, and its application. Background Technology
[0002] In the field of nuclear physics detection technology, boron-coated detectors are important neutron measurement devices, generally used to detect the thermal neutron flux rate in reactors or environments. The core component of a boron-coated detector is the boron-coated electrode. The quality of the boron layer is crucial to the thermal neutron sensitivity of the detector. However, because elemental boron is an inorganic material and non-conductive, it cannot be coated using electroplating. Furthermore, the electrode substrate is typically aluminum or stainless steel, whose surfaces do not readily react with other substances, making proper boron coating impossible. Additionally, based on the principle of neutron measurement in boron-coated detectors, the secondary particles generated by the reaction of B-10 with neutrons have a range of only 5-10 micrometers within the boron layer. Therefore, the thickness of the boron layer should be controlled to 1-5 micrometers (mass thickness 0.2~1 mg / cm²). 2 Exceeding this thickness actually reduces the neutron detection effect. Therefore, the coating thickness should be controlled within this range. The consistency, durability, and impurity content of the boron coating all limit the final neutron sensitivity and application scenarios of the boron-coated detector. According to available information, the main methods used domestically and internationally for manufacturing boron coatings are gas chemical deposition, physical deposition, and brush coating.
[0003] However, existing technologies have some problems in practical applications. First, gas chemical deposition uses complex equipment, and the raw material B2H6 is highly toxic, limiting its use. Physical deposition mainly uses magnetron sputtering, which has a slow deposition rate (20 nm / h), low production efficiency, high auxiliary material ratio in brush coating, and poor coating consistency. Summary of the Invention
[0004] The purpose of this invention is to solve the above-mentioned problems and provide a screen printing coating based on a mixture of metal screen printing solvent and boron powder, which has simple production equipment, high production efficiency, few impurities, and good coating uniformity, as well as its preparation method and application. The coating has a thickness in the micrometer range.
[0005] A first aspect of the present invention provides a method for preparing a screen-printed coating based on a mixture of a metal screen printing solvent and boron powder, the method comprising: Step 1: Prepare screen printing solvent; Step 101: Mix TMPTA2136 screen printing solvent (component is trimethylolpropane triacrylate) with boron powder. The mass ratio of the solid content in TMPTA2136 screen printing solvent to the boron powder is 10-20:80-90. Step 102: Dilute the mixture obtained in step 101 a second time with alcohol to make the solid content in the alcohol 1%~25% by mass, and mix thoroughly and evenly. The dilution ratio is controlled according to the required coating thickness and the thickness of the screen. Taking a 20-micron thick screen as an example, each screen hole can hold a solvent with a thickness of 20 microns. If the solid content in the solvent is about 20%, the final cured coating thickness is about 4 microns. Step 2: Create a wire mesh template; Step 3, screen printing; Step 4: Curing.
[0006] As a preferred embodiment, in the above-mentioned method for preparing the screen-printed coating, in step 101, the particle size D50 of the boron powder is 0.1-5 μm. If the boron powder particles are too fine, they are prone to agglomeration, resulting in poor permeability and reduced coating uniformity during screen printing; if the particles are too coarse, they are difficult to pass through the mesh of a screen with a mesh size of 200 or higher, and are prone to local accumulation, affecting the consistency of the final coating thickness.
[0007] As a preferred embodiment, in the above-mentioned method for preparing the screen printing coating, in step 101, the mass ratio of the solid content in the TMPTA2136 screen printing solvent to the boron powder is 12-18:82-88.
[0008] As a preferred embodiment, in the above-mentioned method for preparing the screen-printed coating, in step 102, the mass percentage of solids in the alcohol is 10% to 25%.
[0009] As a preferred embodiment, in the above-mentioned method for preparing the screen-printed coating, step 2 includes: Step 201: Create a screen printing template according to the shape of the item to be coated. If there is a pattern, create a corresponding screen printing template; if the entire surface is to be coated, use a full-length screen printing template. Step 202: Assemble the silkscreen template with the substrate.
[0010] More preferably, step 2 includes: Step 201: Create a screen printing template according to the three-dimensional shape of the substrate, the size of the area to be coated, and the surface flatness; if a specific pattern needs to be printed, create a screen printing template that matches the pattern; if a full-coverage coating is required on the surface of the substrate, use a patternless "full-through screen" (i.e., all areas of the screen are ink-permeable pores). Step 202: Fit the screen printing template tightly to the substrate using a clamp or vacuum adsorption method to ensure there are no gaps between the template and the substrate, so as to avoid solvent leakage or blurred coating edges during printing.
[0011] As a preferred embodiment, in the above-mentioned method for preparing the screen-printed coating, in step 201, the mesh size of the screen is 200 mesh or larger to facilitate the passage of boron powder.
[0012] In the above-mentioned method for preparing a screen-printed coating, in step 201, the thickness of the screen is selected according to its material and strength. As a preferred option, the thickness of the screen is 10-20 micrometers.
[0013] As a preferred embodiment, in the above-mentioned method for preparing the screen-printed coating, step 3 includes: Step 301: Apply the screen printing solvent evenly to the substrate. If a squeegee is used to apply the coating to the substrate, it usually only needs to be applied once. Step 302: Preliminary drying to remove solvents such as alcohol.
[0014] In the above-mentioned method for preparing screen-printed coatings, the substrate (such as a glass substrate) after ink scraping can be conveyed to the curing oven via a rolling conveyor belt; the scraper can be of the simplest structure, and a suitable scraping structure can be designed according to the substrate; curing is carried out in a high-temperature curing oven, which preferably uses inert gas protection.
[0015] As a preferred embodiment, in the above-mentioned method for preparing the screen-printed coating, the initial drying temperature in step 302 is 80-100℃.
[0016] As a preferred embodiment, in the above-mentioned method for preparing the screen-printed coating, step 4 includes: subjecting the initially dried substrate to secondary curing, and obtaining a substrate with a screen-printed coating after cooling; the secondary curing temperature is 200-250℃, and the time is 30-60 minutes. According to a specific embodiment of the present invention, step 4 includes: step 401, sending the initially dried substrate to a high-temperature curing oven; step 402, performing secondary curing at 200-250℃ for 30-60 minutes; step 403, obtaining a substrate with a boron coating after the temperature drops to room temperature.
[0017] A second aspect of the present invention provides a screen printing coating based on a mixture of metal screen printing solvent and boron powder, which is prepared by the above-described preparation method.
[0018] The third aspect of the present invention provides the application of the above-mentioned screen-printed coating in boron-coated detectors, specifically applicable to the fabrication of boron-containing coatings during the production process of neutron detectors, and also applicable to the fabrication of thin coatings of other inorganic materials.
[0019] Compared with the prior art, the present invention has at least the following beneficial effects: 1. This invention uses TMPTA metal screen printing solvent to mix with boron powder in a suitable solid ratio to form a screen printing solvent, and controls the final boron coating thickness by diluting the screen printing solvent with alcohol twice. This achieves precise adjustment of the coating thickness and solves the problem that traditional boron coating process parameters are difficult to control precisely for coating thickness. 2. This invention employs a combination of low-temperature hot air preliminary drying and high-temperature curing. The solvent is removed by low-temperature hot air preliminary drying, and a strong coating is formed by high-temperature curing, which effectively improves the coating's adhesion and overcomes the shortcomings of traditional boron coatings, such as poor adhesion and easy peeling. 3. This invention further reduces the impurity content in the coating by further decomposing the film-forming material at high temperature, thereby improving the purity and quality of the coating and meeting the high requirements of screen printing quality for products such as solar cells and photovoltaic glass; 4. The coating prepared by this invention has excellent high temperature resistance. It can achieve Grade 1 fastness at 250 degrees Celsius and does not peel off at 400 degrees Celsius, which significantly improves the durability and stability of the coating and can adapt to various complex usage environments. 5. The preparation method of the present invention is simple and controllable, easy to operate, and easy to industrialize, thus solving the problem of low manufacturing efficiency of boron coating.
[0020] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description
[0021] Figure 1 This is a flowchart illustrating one specific embodiment of this application. Detailed Implementation
[0022] The following description provides numerous specific details to offer a more thorough understanding of the technical solutions provided by this invention. However, it will be apparent to those skilled in the art that the technical solutions provided by this invention can be implemented without one or more of these details.
[0023] In this embodiment of the invention, all raw materials are commercially available.
[0024] In this embodiment of the invention, the wire mesh is made of PET; the substrate is made of stainless steel.
[0025] The durability test was conducted using a cross-cut adhesion tester. 1) First, record the quality and thickness of the coating.
[0026] 2) Use a cross-cutting tool to make 10mm wide strips with a length greater than 1mm on the coating surface at an angle of about 45 degrees.
[0027] 3) Then, use coating measurement tape (3M 600) to vertically adhere to the marked area, and gently press the tape with an eraser or your finger to ensure that the coating adheres fully.
[0028] 4) Then quickly peel off the tape.
[0029] 5) Weigh again.
[0030] 6) Calculate the weight loss rate and calculate the coating firmness based on the weight loss rate. Use 0-100 as the score, where 0 is the firmest and the coating weight loss is 0%, and 100 is the weakest and the coating weight loss is 100%.
[0031] Example 1 A method for preparing a screen-printed coating based on a mixture of metal screen printing solvent and boron powder includes the following steps, the process of which can be found in [link to flowchart]. Figure 1 : Step 1: Manufacturing screen printing solvent and substrate treatment: Step 101: Mix TMPTA metal screen printing solvent with boron powder with a particle size D50 of 0.1-5μm at a solid ratio of 10:90, and stir evenly at room temperature to obtain a mixture; Step 102: Dilute the mixture obtained in step 101 a second time using alcohol as a solvent, so that the final solid mass percentage is 20%; Step 103: The solvent obtained in step 102 is continuously stirred and mixed evenly using a stirrer; Step 104: Clean the surface of the substrate to remove oil stains.
[0032] Step 2: Create the wire mesh template: Step 201: Select a 200-mesh screen (approximately 75 micrometers in aperture) with a screen thickness of 20 micrometers, and manufacture a screen printing template according to the shape of the substrate; Step 202: Assemble the screen printing template with the substrate to facilitate coating.
[0033] Step 3, screen printing: Step 301: Use a squeegee to evenly apply the screen printing solvent to the substrate, applying one coat. Step 302: Perform preliminary drying on the substrate at 90℃ for 5-10 minutes to remove the solvent; Step 4, Curing: Step 401: Continue to transfer the substrate to the high-temperature curing oven; Step 402: Perform a second curing at 200℃ for 30 minutes; Step 403: After the temperature drops to room temperature, a boron-coated substrate is obtained.
[0034] Example 2 The difference from Example 1 is that in step 101, TMPTA metal screen printing solvent and boron powder with a particle size D50 of 0.1-5μm are mixed at a solid ratio of 15:85.
[0035] Example 3 The difference from Example 1 is that in step 101, TMPTA metal screen printing solvent and boron powder with a particle size D50 of 0.1-5μm are mixed at a solid ratio of 20:80.
[0036] Comparative Example 1 The difference from Example 1 is that the TMPTA metal screen printing solvent was replaced with H85-9032 ink. After mixing with boron powder at a ratio of 10:90 and then diluting, the screen printing was blocky and could not be uniform.
[0037] Comparative Example 2 The difference from Example 1 is that the TMPTA metal screen printing solvent was replaced with H65-9002T self-drying ink, which, when mixed with boron powder at a ratio of 10:90, could not be screen printed evenly.
[0038] Comparative Example 3 The difference from Example 1 is that the TMPTA metal screen printing solvent is replaced with environmentally friendly water-based acrylic ink. After being mixed with boron powder at a ratio of 10:90, it forms lumps and cannot be screen printed evenly.
[0039] Comparative Example 4 The difference from Example 1 is that the TMPTA metal screen printing solvent and boron powder with a particle size of 0.1-5μm were mixed at a solid ratio of 25:75, resulting in a smaller proportion of boron by mass, which affected the final test results.
[0040] Comparative Example 5 The difference from Example 1 is that the TMPTA metal screen printing solvent is mixed with boron powder with a particle size of 0.1-5μm at a solid ratio of 5:95, resulting in less material in the final film and poorer adhesion.
[0041] Comparative Example 6 The difference from Example 1 is that acetone was used as a solvent for secondary dilution, which evaporated quickly, affecting the screen printing process and causing the solvent to become viscous, making screen printing impossible.
[0042] Test Example 1 The products obtained in the examples and comparative examples were subjected to a durability test using the cross-cut adhesion test. The results are shown in Table 1. Table 1
[0043] Test Example 2 The products obtained in Examples 1-3 and Comparative Example 4 were subjected to high-temperature durability tests. High-temperature durability was tested by baking samples at different high temperatures and then removing them for adhesion testing. After reaching 250℃, the coating cured better and exhibited superior adhesion.
[0044] Table 2
[0045] Test Example 3 The products obtained in Examples 1-3 and Comparative Example 4 were subjected to radiation resistance tests. Radiation resistance was assessed by subjecting the samples to cumulative dose irradiation, followed by a adhesion test. The coating was found to be more robust due to radiation cross-linking.
[0046] Table 3
[0047] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A method for preparing a screen-printed coating based on a mixture of metal screen printing solvent and boron powder, characterized in that, The preparation method includes: Step 1: Prepare screen printing solvent; Step 101: Mix TMPTA2136 screen printing solvent with boron powder. The mass ratio of the solid content in TMPTA2136 screen printing solvent to the boron powder is 10-20:80-90. Step 102: Dilute the mixture obtained in step 101 a second time with alcohol to make the mass percentage of solids in the alcohol 1%~25%, and mix thoroughly. Step 2: Create a wire mesh template; Step 3, screen printing; Step 4: Curing.
2. The method for preparing a screen-printed coating according to claim 1, characterized in that, In step 101, the particle size D50 of the boron powder is 0.1-5 μm.
3. The method for preparing a screen-printed coating according to claim 1, characterized in that, Satisfy at least one of the following characteristics: In step 101, the mass ratio of solid content in TMPTA2136 screen printing solvent to boron powder is 12-18:82-88; In step 102, the mass percentage of solids in the alcohol is 10% to 25%.
4. The method for preparing a screen-printed coating according to claim 1, characterized in that, Step 2 includes: Step 201: Create a screen printing template according to the shape of the item to be coated. If there is a pattern, create a corresponding screen printing template; if the entire surface is to be coated, use a full-length screen printing template. Step 202: Assemble the silkscreen template with the substrate.
5. The method for preparing a screen-printed coating according to claim 4, characterized in that, Satisfy at least one of the following characteristics: In step 201, the mesh size of the wire mesh is 200 mesh or larger; In step 201, the thickness of the screen is 10-20 micrometers.
6. The method for preparing a screen-printed coating according to claim 1, characterized in that, Step 3 includes: Step 301: Apply the screen printing solvent evenly to the substrate; Step 302: Preliminary drying.
7. The method for preparing a screen-printed coating according to claim 6, characterized in that, In step 302, the initial drying temperature is 80-100℃.
8. The method for preparing a screen-printed coating according to claim 1, characterized in that, Step 4 includes: subjecting the initially dried substrate to secondary curing and cooling to obtain a substrate with a screen-printed coating; the secondary curing temperature is 200-250℃ and the time is 30-60 minutes.
9. A screen-printed coating based on a mixture of metal screen printing solvent and boron powder, characterized in that, It is prepared by the preparation method described in any one of claims 1-8.
10. The application of the screen-printed coating of claim 9 in a boron-coated detector.