Non-solvent type three-proofing protective agent as well as preparation method and application thereof

Abstract

The invention discloses a non-solvent type three-proofing protective agent as well as a preparation method and application thereof. The non-solvent type three-proofing protective agent comprises the following raw materials in percentage by weight: 3.5-3.7% of water-soluble polyurethane resin; 5.3 to 5.5% of water-soluble vinyl acetate resin; 0.44 to 0.46 percent of sodium dodecyl benzene sulfonate; 0.17-0.19% of an anti-wear agent; 0.08 to 0.10 percent of a glazing agent; 0.44%-0.46% of a dispersing agent; and 89.7 to 89.9% of a solvent. The three-proofing protective agent disclosed by the invention solves the problems that a gloss oil layer sprayed on the surface of a relay product is dissolved, floats, falls off and changes color and the same problems of other electronic devices needing surface protection, and has the excellent characteristics of certain solvent resistance, temperature resistance, weather resistance and the like; and after the protective agent forms a film, the adhesive force and the flexibility are not lower than the first-grade standard.

Description

Technical Field

[0001] The invention belongs to the technical field of membrane materials, and specifically relates to a non-solvent type three-proof protective agent and a preparation method and application thereof. Background Art

[0002] At present, the organic varnish used for surface protection of relays in the electronic component industry has the following problems: 1. Poor resistance to organic solvents, such as X-2 nitro lacquer thinner, alcohol, acetone, etc. The varnish layer will dissolve, swell and fall off during the cleaning process of the relay before use in the whole machine factory; 2. The varnish layer has poor weather resistance. After the relay is stored for a period of time (30 days), the varnish layer will become flowery and discolored; 3. The organic varnish layer has poor adhesion. The varnish layer will wear and fall off during the packaging and transportation of the relay; therefore, there is an urgent need to develop a new type of relay surface protective agent. Summary of the invention

[0003] In order to solve the above problems existing in the prior art, the present invention provides a non-solvent type three-proof protective agent and its preparation method and application. The technical problem to be solved by the present invention is achieved by the following technical solution: A non-solvent type three-proof protective agent comprises the following raw materials in weight ratio: 3.5-3.7% water-soluble polyurethane resin; 5.3-5.5% water-soluble vinyl acetate resin; 0.44-0.46% sodium dodecylbenzene sulfonate; 0.17-0.19% wear-resistant agent; 0.08-0.10% polishing agent; 0.44-0.46% dispersant; and 89.7-89.9% solvent.

[0004] Furthermore, the wear-resistant agent is polytetrafluoroethylene; the polishing agent is diaminobenzene disulfonic acid; the dispersant is condensed sodium silicate; and the solvent is deionized water.

[0005] Another embodiment of the present invention also discloses a method for preparing a non-solvent type three-proof protective agent, comprising the following steps: Step 1: Place 3.5-3.7% of water-soluble polyurethane resin and 5.3-5.5% of water-soluble vinyl acetate resin in a container, heat and stir until the solution becomes uniformly translucent; Step 2: Add 0.44~0.46% of sodium dodecylbenzene sulfonate, 0.17~0.19% of anti-wear agent, 0.08~0.10% of glazing agent, 0.44~0.46% of dispersant and 89.7~89.9% of deionized water to the above solution in sequence, continue heating and stirring until the solution becomes uniform and transparent, thereby obtaining a non-solvent type three-proof protective agent.

[0006] Furthermore, the heating temperature in step 1 is 75-85° C., and the stirring time is 4.5-5.5 min.

[0007] Another embodiment of the present invention further discloses the use of the non-solvent type three-proofing protective agent in the above embodiment as a surface coating for a relay.

[0008] Beneficial effects of the present invention: 1. The three-proof protective agent of the present invention solves the problem of dissolution, fading and discoloration of the varnish layer sprayed on the surface of relay products and the same problem existing in other electronic devices that require surface protection; 2. The three-proof protective agent has good protective performance, and has certain excellent properties such as solvent resistance, temperature resistance, and weather resistance. The adhesion and flexibility of the protective agent after film formation are not lower than the first-class standard; 3. The invention has a simple formula, low cost, green and environmental protection, easy production and excellent performance. It is odorless and pollution-free during the construction process and does not cause any harm to the operator's body. It is an environmentally friendly protective agent and can be mass-produced. In addition, the three-proof protective agent improves the economic benefits and technical level of the enterprise, and gives the product a larger market space.

[0009] The present invention will be further described in detail below with reference to the embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 The nickel-plated relay housing is produced in small batches by the applicant using the three-proof protective agent of the present invention; Figure 2 It is a photo of the copper standard test plate of three samples in the comparative test of adhesion and flexibility of the three-proof protective agent of the present invention; Figure 3(a)~3(c) This is the test report of three samples in the comparative test of adhesion and flexibility of the three-proof protective agent of the present invention; Figure 4 This is a photo of the heat resistance test of the three-proof protective agent of the present invention; Figure 5(a)~5(b) The test report of the temperature shock resistance, salt spray resistance and durability test of the three-proof protective agent of the present invention; Figure 6(a)~6(b) The test report of the three-proof protective agent of the present invention for resistance to steady-state damp heat, resistance to fluorinated oil, resistance to coupling agent and resistance to pure water; Figure 7 These are photos of the three-proof protective agent of the present invention and the comparative sample in a simulated humid environment; Figure 8(a)~8(b) This is the result of the comparative test of the three-proof protective agent in a humid environment. DETAILED DESCRIPTION

[0011] The present invention is further described in detail below with reference to specific embodiments, but the embodiments of the present invention are not limited thereto. Example 1

[0012] The embodiment of the present invention provides a non-solvent type three-proof protective agent, comprising the following raw materials in weight ratio: 3.5-3.7% water-soluble polyurethane resin; 5.3-5.5% water-soluble vinyl acetate resin; 0.44-0.46% sodium dodecylbenzene sulfonate; 0.17-0.19% wear agent; 0.08-0.10% polishing agent; 0.44-0.46% dispersant; 89.7-89.9% solvent.

[0013] Specifically, the wear-resistant agent is polytetrafluoroethylene; the polishing agent is diaminobenzene disulfonic acid; the dispersant is condensed sodium silicate; and the solvent is deionized water. Example 2

[0014] The embodiment of the present invention provides a non-solvent type three-proof protective agent, comprising the following raw materials in weight ratio: 3.6% water-soluble polyurethane resin; 5.4% water-soluble vinyl acetate resin; 0.45% sodium dodecylbenzene sulfonate; 0.18% wear-resistant agent; 0.09% polishing agent; 0.45% dispersant; and 89.8% solvent.

[0015] Specifically, the wear-resistant agent is polytetrafluoroethylene; the polishing agent is diaminobenzene disulfonic acid; the dispersant is condensed sodium silicate; and the solvent is deionized water. Example 3

[0016] The present invention provides a method for preparing the non-solvent type three-proof protective agent of Example 1 and Example 2, which specifically comprises: Step 1: Use an electronic balance with an accuracy of 0.01g to place 4g of water-soluble polyurethane resin and 6g of water-soluble vinyl acetate resin in a beaker, heat to 80°C, and then use a small electric stirrer to stir for 5 minutes, so that the solution in the beaker is uniformly translucent; Step 2: Then add 0.5g sodium dodecylbenzene sulfonate, 0.2g polytetrafluoroethylene, 0.1g diaminobenzene disulfonic acid, 0.5g condensed sodium silicate and 100mL of deionized water to the above solution in the beaker, continue heating to 80°C and stir for 5 minutes to make the solution in the beaker present a uniform transparent state. At this point, a non-solvent type three-proof protective agent is formed.

[0017] The water-soluble polyurethane resin and the water-soluble vinyl acetate resin are both used as film-forming substances of the three-proof protective agent; the role of sodium dodecylbenzene sulfonate is to make the three-proof protective agent form a uniform and stable emulsion system; the role of polytetrafluoroethylene is to increase the wear resistance of the protective agent after curing; the role of diaminobenzene disulfonic acid is to increase the brightness of the protective agent after curing; the role of condensed sodium silicate is to make various additives evenly dispersed. Example 4

[0018] The embodiment of the present invention provides an application of the non-solvent type three-proof protective agent in Embodiment 1 and Embodiment 2 as a relay surface coating.

[0019] Specifically, add the prepared non-solvent type three-proof surface protective agent to the spraying equipment, adjust the spray gun pressure according to the spray equipment operating procedures, and adjust the spray gun nozzle needle valve at the same time so that the liquid sprayed is in a uniform mist. Then place the clean relay on the spray fixture, and spray the relay three times continuously and evenly on the front, back, left, right and top surface, with an interval of 1 minute between each time. No preheating is required before each spraying, and spraying at room temperature is sufficient. Ensure that the relay surface has a uniform coating with a thickness of 15μm-20μm. Put the sprayed relay in an oven at 100℃±10℃ for 30 minutes, and take it out and return it to room temperature to form a relay surface protective film.

[0020] In addition, when the sprayed coating needs to be reworked, it can be soaked in industrial alcohol for 30 minutes to 60 minutes, scrubbed with a soft brush, and then rinsed with clean anhydrous ethanol, and then dried naturally or baked.

[0021] The non-solvent type three-proof protective agent is prepared by dissolving water-soluble polyurethane resin and water-soluble vinyl acetate resin in a certain proportion, and then adding emulsifier sodium dodecylbenzene sulfonate, wear-resistant agent, glazing agent, dispersant and deionized water to form a uniform and stable emulsion system in water, namely, a water-based three-proof protective agent. When the water-based three-proof protective agent is sprayed on the surface of the relay cover, the free wear-resistant particles and emulsion molecules in the system are combined with the water-soluble resin through diffusion and penetration to form a wet film. The wet film is dried to evaporate the water molecules therein, and the water-soluble resin is cross-linked and cured with the emulsion to form a three-proof protective film. Since the three-proof protective agent does not contain organic solvents, its solvent resistance is better than that of organic varnish, thereby playing a stable and long-lasting three-proof protective role on the metal surface. In addition, no organic solvent is volatilized during the drying process, so there is no odor, the use cost is low, there is no harm to the human body, and it is beneficial to environmental protection.

[0022] At the end of June 2023, the applicant selected 189 relays for small-batch trial spraying. Figure 1 As shown, the results are basically good. Except for the products sampled for preliminary testing, the rest of the products have been put into storage and delivered.

[0023] Economic benefits: The cost of the three-proof protective agent of the present invention is much lower than the imported ink currently used by the applicant, and because the solvent is pure water, the cost is even lower. Before spraying the three-proof protective agent of the present invention, the product appearance qualification rate was only 32%, while after spraying, the product appearance qualification rate was greatly improved, and the rework cost was reduced, thereby further reducing the production cost of the enterprise.

[0024] The present invention conducts the following performance tests on the non-solvent type three-proof protective agent: (1) Adhesion and flexibility test The applicant prepared a standard copper test plate by mixing the imported ink used previously, the polyurethane three-proof paint used now, and the three-proof protective agent of the present invention according to their respective coating methods. Figure 2 As shown, and then test according to the paint film adhesion and flexibility test method, the test report is as follows Figure 3(a)~3(c) As shown, 3(a) is the test report of imported ink; 3(b) is the test report of polyurethane three-proof paint; 3(c) is the test report of the three-proof protective agent of the present invention; the adhesion and flexibility of the three samples all reach the level 1 standard, indicating that the three-proof protective agent of the present invention can be used for the protection of the surface of the relay cover.

[0025] (2) Solubility resistance test Since the finished relays are most exposed to alcohol and acetone for cleaning before screening and user use, the present invention only conducts alcohol and acetone resistance tests, and selects the imported ink used originally, the polyurethane three-proof paint used now, and the three-proof protective agent of the present invention for comparative experiments. The test results are shown in Table 1:

[0026] It can be seen from the test data that the three-proof protective agent of the present application has the best alcohol resistance and the best acetone resistance.

[0027] (3) Temperature resistance test According to the spraying process of the three-proof protective agent of the present application, several relay covers are sprayed, cured at room temperature for 1 hour, and then placed in an oven at 150°C for continuous baking for 8 hours. The varnish coating on the surface of the relay cover is observed. Figure 4 As shown, it is visible to the naked eye that the coating has no discoloration and no cracking. The temperature rise of the coil and the ambient operating temperature of a general relay will not exceed 150°C at most, indicating that the temperature resistance of the three-proof protective agent of the present invention can fully meet the product requirements.

[0028] (4) Temperature shock resistance, salt spray resistance and durability tests The test results are shown in Table 2 and Figure 5(a)~5(b) As shown: Table 2 Comparison of the results of temperature shock resistance, salt spray resistance and durability tests

[0029] (4) Steady-state heat and humidity resistance, fluorinated oil resistance, coupling agent resistance and pure water resistance tests According to the use environment of the relay cover after spraying the three-proof protective agent, and the situation that the relay cover will be exposed to fluorine oil, coupling agent and pure water in the subsequent process, the relay cover sprayed with the three-proof protective agent is subjected to steady-state damp heat resistance, fluorine oil resistance, coupling agent resistance and pure water resistance tests. The test results are as follows: Figure 6(a)~6(b) As shown, after testing, all the above items are qualified.

[0030] (5) Wet environment simulation test Artificially simulate a humid environment: take three relay covers coated with imported ink, the three-proof protective agent of the present invention, and no coating, put them into a PE lined packaging box, put them into a sealed drying bottle, take out the desiccant in the drying bottle, put in a cup of tap water, and Figure 7 As shown, a humid environment was simulated and placed for 5 months.

[0031] After 5 months of storage under the above conditions, the samples were taken out for comparison. The comparison results are as follows: Figure 8(a) and 8(b) As shown in the photos, it can be seen that the cover that has not been coated with any protective agent has the most serious discoloration, the cover that has been coated with the imported ink coating has a slight discoloration, and the cover that has been coated with the protective agent of the present invention has almost no discoloration and has the best protective effect.

[0032] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. A non-solvent type three-proof protective agent, characterized in that: The invention comprises the following raw materials in weight ratio: 3.5-3.7% water-soluble polyurethane resin; 5.3-5.5% water-soluble vinyl acetate resin; 0.44-0.46% sodium dodecylbenzene sulfonate; 0.17-0.19% wear-resistant agent; 0.08-0.10% polishing agent; 0.44-0.46% dispersant; and 89.7-89.9% solvent.

2. The non-solvent type three-proof protective agent according to claim 1, characterized in that: The wear-resistant agent is polytetrafluoroethylene; the polishing agent is diaminobenzene disulfonic acid; the dispersant is condensed sodium silicate; and the solvent is deionized water.

3. A method for preparing the non-solvent type three-proof protective agent according to claim 1-2, characterized in that: The following steps are involved: Step 1: Place 3.5-3.7% of water-soluble polyurethane resin and 5.3-5.5% of water-soluble vinyl acetate resin in a container, heat and stir until the solution becomes uniform and translucent; Step 2: Add 0.44~0.46% of sodium dodecylbenzene sulfonate, 0.17~0.19% of anti-wear agent, 0.08~0.10% of glazing agent, 0.44~0.46% of dispersant and 89.7~89.9% of deionized water to the above solution in sequence, continue heating and stirring until the solution becomes uniform and transparent, thereby obtaining a non-solvent type three-proof protective agent.

4. The method for preparing the non-solvent type three-proof protective agent according to claim 3, characterized in that: The heating temperature in step 1 is 75-85° C., and the stirring time is 4.5-5.5 min.

5. Use of the non-solvent type three-proof protective agent according to any one of claims 1 to 2 as a relay surface coating.

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