Ultrasonic cleaning process for plastic toy products

Abstract

The invention discloses an ultrasonic cleaning process for plastic toy products, and belongs to the technical field of cleaning. Comprising the following steps that the plastic toy product is soaked in cleaning liquid, ultrasonic waves are applied to assist cleaning, then the plastic toy product is fished out and washed with water, the operation is repeated, and cleaning is completed; the cleaning solution comprises a surfactant, a penetrant, sodium hydroxide, a builder and deionized water; the builder is of a microsphere structure with a core formed by compounding porous calcium carbonate and Al2ZnO4 crystals and a shell formed by crosslinking sodium alginate and calcium ions. Ultrasonic waves are used for assisting cleaning liquid in cleaning, resonance friction is generated between ultrasonic vibration frequency and the cleaning liquid, and stubborn oil stains are cleaned up.

Description

Technical Field

[0001] This invention belongs to the field of cleaning technology, specifically relating to an ultrasonic cleaning process for plastic toy products. Background Technology

[0002] PVC plastic is widely used in toy manufacturing due to its low cost and excellent processing performance. To improve the flexibility and processing fluidity of PVC materials, a certain amount of plasticizer needs to be added during production. However, the plasticizer and PVC molecular chains are only physically bonded, and it easily migrates from the material's interior to the surface during production, processing, and subsequent storage. The leached plasticizer is sticky and easily adheres to dust and impurities in the production environment, forming complex oil stains. These oil stains have a strong adsorption effect on the surface of PVC toys, making them difficult to remove completely using conventional cleaning methods.

[0003] Currently, the mainstream cleaning solutions for PVC products on the market mostly use organic solvents such as thinner. Although these solvents can dissolve surface oil stains to a certain extent, they have significant drawbacks: these solvents can only dissolve oil stains in the system and cannot completely separate the oil stains. When the PVC toy is removed from the solvent, the dissolved oil stains are easy to re-adhere to the product surface, resulting in poor cleaning effect and difficulty in meeting the quality requirements for product surface cleanliness. Summary of the Invention

[0004] The purpose of this invention is to provide an ultrasonic cleaning process for plastic toys, which improves the removal effect of stubborn oil stains on the surface of PVC materials.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] An ultrasonic cleaning process for plastic toys includes the following steps: immersing the plastic toys in a cleaning solution, applying ultrasonic-assisted cleaning, then removing them and rinsing them with water, repeating the above operation to complete the cleaning;

[0007] The cleaning solution includes surfactants, penetrants, sodium hydroxide, detergent additives, and deionized water;

[0008] The detergent additive is a microsphere structure with a core formed by a composite of porous calcium carbonate and Al2ZnO4 crystals and a shell formed by cross-linking sodium alginate with calcium ions.

[0009] As a preferred embodiment of the present invention, the mass ratio of the surfactant, penetrant, sodium hydroxide, detergent, and deionized water is 10-18:5-7:4-8:0.8-1.5:65.5-80.2.

[0010] As a preferred embodiment of the present invention, the power of the ultrasonic wave is 200-400W and the ultrasonic frequency is 25-55kHz.

[0011] As a preferred embodiment of the present invention, the surfactant includes di(hydroxyethyl)laurylamine oxide, dodecyl glucoside, sodium dodecylbenzenesulfonate, and fatty alcohol polyoxyethylene ether AEO-3.

[0012] As a preferred embodiment of the present invention, the mass ratio of di(hydroxyethyl) laurylamine oxide, dodecyl glucoside, sodium dodecylbenzenesulfonate, and fatty alcohol polyoxyethylene ether AEO-3 is 3-5:2-4:1-3:4-8.

[0013] As a preferred embodiment of the present invention, the preparation method of the detergent additive includes the following steps:

[0014] S1. Take aluminum source, zinc source and ethanol, mix them, disperse them by ultrasonication, put them into oleic acid, heat and stir them in an oil bath at 115-125℃, dry them, calcine them at 750-850℃, grind them to obtain composite powder.

[0015] S2. After the seashells are acid-washed and water-washed, dried, crushed, sieved, and calcined at 1000℃, porous calcium carbonate is obtained.

[0016] S3. Take the composite powder and porous calcium carbonate, mix them, disperse them in an aqueous solution of sodium alginate, then add them dropwise to an aqueous solution of calcium chloride, let stand, filter, take the solid phase, wash and dry to obtain the detergent additive.

[0017] As a preferred technical solution of the present invention, in step S1, the ratio of aluminum source, zinc source, ethanol and oleic acid is 1.2-1.6g: 1-1.5g: 60-80mL: 50-60g.

[0018] As a preferred technical solution of the present invention, in step S3, the ratio of the composite powder, porous calcium carbonate, sodium alginate aqueous solution, and calcium chloride aqueous solution is 0.22-0.32g: 1.04-1.28g: 100mL: 5-7mL.

[0019] The beneficial effects of this invention are:

[0020] (1) The ultrasonic cleaning process for plastic toy products disclosed in this invention uses ultrasonic-assisted cleaning fluid to clean oil stains. The ultrasonic vibration frequency and the detergent particles in the cleaning fluid resonate with each other. The detergent particles and the product generate resonance friction in the water due to the same polarity of the resonance. This causes the detergent particles to disrupt the oil film adsorption balance on the surface of the product, allowing the oil stains to peel off from the surface of the product. The stubborn oil stains are cleaned by the adsorption effect of the detergent particles.

[0021] (2) The ultrasonic cleaning process for plastic toy products disclosed in this invention adds di(hydroxyethyl) laurylamine oxide, dodecyl glucoside, sodium dodecylbenzene sulfonate, and fatty alcohol polyoxyethylene ether AEO-3 to the cleaning solution. The four surfactants work synergistically to reduce the interfacial tension between the product and the oil stains, enhance wetting and penetration, and form mixed micelles to efficiently encapsulate the oil stains and form a stable water-in-oil emulsion. This prevents the oil stains from re-aggregating or adhering back to the PVC surface, and the synergistic adsorption and strengthening effect promotes the removal of oil stains, thereby improving the oil stain removal effect.

[0022] (3) The ultrasonic cleaning process for plastic toy products disclosed in this invention involves preparing a cleaning aid. In the ultrasonic field, the rigid structure of the core of the cleaning aid microspheres (Al2ZnO4 crystal combined with porous calcium carbonate) resonates and collides with the oil stains. The impact force directly breaks the adsorption balance between the oil stains and the surface of the PVC product, promoting the peeling of the oil stains. The oleic acid-modified Al2ZnO4 crystals enhance the interfacial affinity for the oil stains. Furthermore, through the steric hindrance effect of the organic long chain, the cleaning aid particles are prevented from agglomerating, ensuring uniform dispersion in the cleaning solution and expanding the contact range with the oil stains. The Al2ZnO4 crystal structure formed by zinc and aluminum composite can provide dual adsorption sites. The peeled oil stains are first adsorbed by the active sites of the Al2ZnO4 crystals and then physically intercepted through the pore structure of porous calcium carbonate, forming a dual effect of crystal adsorption and pore interception, separating the oil stains from the cleaning solution and avoiding secondary adhesion. Detailed Implementation

[0023] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with embodiments, is provided below.

[0024] Example 1

[0025] An ultrasonic cleaning process for plastic toys includes the following steps:

[0026] Immerse the plastic toys in a 40°C cleaning solution for 10 minutes, apply ultrasonic cleaning for 3 minutes, then remove and rinse with water. Repeat this process 3 times to complete the cleaning.

[0027] The ultrasonic wave has a power of 200W and a frequency of 25kHz.

[0028] The cleaning solution comprises a surfactant, a penetrant, sodium hydroxide, a detergent builder, and deionized water; the mass ratio of the surfactant, penetrant, sodium hydroxide, detergent builder, and deionized water is 10:5:4:0.8:80.2.

[0029] The surfactant comprises di(hydroxyethyl) laurylamine oxide, dodecyl glucoside, sodium dodecylbenzene sulfonate, and fatty alcohol polyoxyethylene ether AEO-3; the mass ratio of di(hydroxyethyl) laurylamine oxide, dodecyl glucoside, sodium dodecylbenzene sulfonate, and fatty alcohol polyoxyethylene ether AEO-3 is 3:2:1:4.

[0030] The penetrant is nonylphenol polyoxyethylene (9) ether;

[0031] The preparation method of the detergent additive includes the following steps:

[0032] S1. Mix zinc chloride, aluminum chloride, and ethanol, ultrasonically disperse for 15 min, add to oleic acid, heat and stir in an oil bath at 115℃ for 2 h, dry at 380℃ for 8 h, calcine at 750℃ for 3 h, grind to obtain composite powder; the ratio of aluminum chloride, zinc chloride, ethanol, and oleic acid is 1.2 g: 1 g: 60 mL: 50 g.

[0033] S2. After acid washing and water washing, the shells are dried, crushed, passed through a 100-mesh sieve, and calcined at 1000℃ for 4 hours to obtain porous calcium carbonate.

[0034] S3. Take the composite powder and porous calcium carbonate, mix them, disperse them in sodium alginate aqueous solution, and then add them dropwise to calcium chloride aqueous solution at a rate of 1 mL / min. Let stand for 1 h, filter, take the solid phase, wash it, immerse it in 0.5 mol / L chloroacetic acid solution, and adjust the pH to 8 with 0.1 mol / L sodium hydroxide solution. After standing and solidifying for 10 h, take it out, wash it, and dry it to obtain the detergent additive. The ratio of the composite powder, porous calcium carbonate, sodium alginate aqueous solution and calcium chloride aqueous solution is 0.22 g: 1.04 g: 100 mL: 5 mL; the mass fraction of the sodium alginate aqueous solution is 5%; and the concentration of the calcium chloride aqueous solution is 15 g / L.

[0035] Example 2

[0036] An ultrasonic cleaning process for plastic toys includes the following steps:

[0037] Immerse the plastic toys in a 45°C cleaning solution for 15 minutes, apply ultrasonic cleaning for 4 minutes, then remove and rinse with water. Repeat this process 3 times to complete the cleaning.

[0038] The ultrasonic wave has a power of 300W and a frequency of 40kHz.

[0039] The cleaning solution comprises a surfactant, a penetrant, sodium hydroxide, a detergent builder, and deionized water; the mass ratio of the surfactant, penetrant, sodium hydroxide, detergent builder, and deionized water is 14:6:6:1.2:72.8.

[0040] The surfactant comprises di(hydroxyethyl) laurylamine oxide, dodecyl glucoside, sodium dodecylbenzenesulfonate, and fatty alcohol polyoxyethylene ether AEO-3; the mass ratio of di(hydroxyethyl) laurylamine oxide, dodecyl glucoside, sodium dodecylbenzenesulfonate, and fatty alcohol polyoxyethylene ether AEO-3 is 4:3:2:6.

[0041] The penetrant is nonylphenol polyoxyethylene (9) ether;

[0042] The preparation method of the detergent additive includes the following steps:

[0043] S1. Mix zinc chloride, aluminum chloride, and ethanol, ultrasonically disperse for 20 min, add to oleic acid, heat and stir in an oil bath at 120℃ for 3 h, dry at 400℃ for 9 h, calcine at 800℃ for 4 h, grind to obtain composite powder; the ratio of aluminum chloride, zinc chloride, ethanol, and oleic acid is 1.4 g: 1.3 g: 70 mL: 55 g;

[0044] S2. After acid washing and water washing, the shells are dried, crushed, passed through a 150-mesh sieve, and calcined at 1000℃ for 5 hours to obtain porous calcium carbonate.

[0045] S3. Take the composite powder and porous calcium carbonate, mix them, disperse them in sodium alginate aqueous solution, and then add them dropwise to calcium chloride aqueous solution at a rate of 1.5 mL / min. Let it stand for 1.5 h, filter, take the solid phase, wash it, immerse it in 0.5 mol / L chloroacetic acid solution, and adjust the pH to 8 with 0.1 mol / L sodium hydroxide solution. After standing and solidifying for 10 h, take it out, wash it, and dry it to obtain the detergent additive. The ratio of the composite powder, porous calcium carbonate, sodium alginate aqueous solution and calcium chloride aqueous solution is 0.27 g: 1.16 g: 100 mL: 6 mL; the mass fraction of the sodium alginate aqueous solution is 5%; and the concentration of the calcium chloride aqueous solution is 15 g / L.

[0046] Example 3

[0047] An ultrasonic cleaning process for plastic toys includes the following steps:

[0048] Immerse the plastic toys in a 50°C cleaning solution for 20 minutes, apply ultrasonic cleaning for 5 minutes, then remove and rinse with water. Repeat this process 3 times to complete the cleaning.

[0049] The ultrasonic wave has a power of 400W and a frequency of 55kHz.

[0050] The cleaning solution comprises a surfactant, a penetrant, sodium hydroxide, a detergent builder, and deionized water; the mass ratio of the surfactant, penetrant, sodium hydroxide, detergent builder, and deionized water is 18:7:8:1.5:65.5.

[0051] The surfactant comprises di(hydroxyethyl) laurylamine oxide, dodecyl glucoside, sodium dodecylbenzene sulfonate, and fatty alcohol polyoxyethylene ether AEO-3; the mass ratio of di(hydroxyethyl) laurylamine oxide, dodecyl glucoside, sodium dodecylbenzene sulfonate, and fatty alcohol polyoxyethylene ether AEO-3 is 5:4:3:8.

[0052] The penetrant is nonylphenol polyoxyethylene (9) ether;

[0053] The preparation method of the detergent additive includes the following steps:

[0054] S1. Mix zinc chloride, aluminum chloride, and ethanol, ultrasonically disperse for 25 min, add to oleic acid, heat and stir in an oil bath at 125℃ for 4 h, dry at 420℃ for 10 h, calcine at 850℃ for 5 h, grind to obtain composite powder; the ratio of aluminum chloride, zinc chloride, ethanol, and oleic acid is 1.6 g: 1.5 g: 80 mL: 60 g;

[0055] S2. After the seashells are acid-washed and water-washed, dried, crushed, passed through a 200-mesh sieve, and calcined at 1000℃ for 6 hours, porous calcium carbonate is obtained.

[0056] S3. Take the composite powder and porous calcium carbonate, mix them, disperse them in sodium alginate aqueous solution, and then add them dropwise to calcium chloride aqueous solution at a rate of 2 mL / min. Let stand for 2 hours, filter, take the solid phase, wash it, immerse it in 0.5 mol / L chloroacetic acid solution, and adjust the pH to 8 with 0.1 mol / L sodium hydroxide solution. After standing and solidifying for 10 hours, take it out, wash it, and dry it to obtain the detergent additive. The ratio of the composite powder, porous calcium carbonate, sodium alginate aqueous solution and calcium chloride aqueous solution is 0.32 g: 1.28 g: 100 mL: 7 mL; the mass fraction of the sodium alginate aqueous solution is 5%; and the concentration of the calcium chloride aqueous solution is 15 g / L.

[0057] Comparative Example 1

[0058] The difference from Example 2 is that the mass ratio of di(hydroxyethyl)laurylamine oxide, dodecyl glucoside, sodium dodecylbenzenesulfonate, and fatty alcohol polyoxyethylene ether AEO-3 in the surfactant is 0:5:4:6.

[0059] Comparative Example 2

[0060] The difference from Example 2 is that the mass ratio of di(hydroxyethyl)laurylamine oxide, dodecyl glucoside, sodium dodecylbenzenesulfonate, and fatty alcohol polyoxyethylene ether AEO-3 in the surfactant is 4:0:5:6.

[0061] Comparative Example 3

[0062] The difference from Example 2 is that the mass ratio of di(hydroxyethyl)laurylamine oxide, dodecyl glucoside, sodium dodecylbenzenesulfonate, and fatty alcohol polyoxyethylene ether AEO-3 in the surfactant is 4:5:0:6.

[0063] Comparative Example 4

[0064] The difference from Example 2 is that the mass ratio of di(hydroxyethyl)laurylamine oxide, dodecyl glucoside, sodium dodecylbenzenesulfonate, and fatty alcohol polyoxyethylene ether AEO-3 in the surfactant is 6:5:4:0.

[0065] Comparative Example 5

[0066] The difference from Example 2 is that the preparation method of the detergent builder includes the following steps:

[0067] S1. Take zinc chloride, aluminum chloride and ethanol, mix them, ultrasonically disperse them for 20 min, dry them at 80℃ for 9 h, calcine them at 800℃ for 4 h, grind them to obtain composite powder; the ratio of aluminum chloride, zinc chloride and ethanol is 1.4 g: 1.3 g: 70 mL.

[0068] S2. After acid washing and water washing, the shells are dried, crushed, passed through a 150-mesh sieve, and calcined at 1000℃ for 5 hours to obtain porous calcium carbonate.

[0069] S3. Take the composite powder and porous calcium carbonate, mix them, disperse them in sodium alginate aqueous solution, and then add them dropwise to calcium chloride aqueous solution at a rate of 1.5 mL / min. Let it stand for 1.5 h, filter, take the solid phase, wash it, immerse it in 0.5 mol / L chloroacetic acid solution, and adjust the pH to 8 with 0.1 mol / L sodium hydroxide solution. After standing and solidifying for 10 h, take it out, wash it, and dry it to obtain the detergent additive. The ratio of the composite powder, porous calcium carbonate, sodium alginate aqueous solution and calcium chloride aqueous solution is 0.27 g: 1.16 g: 100 mL: 6 mL; the mass fraction of the sodium alginate aqueous solution is 5%; and the concentration of the calcium chloride aqueous solution is 15 g / L.

[0070] Comparative Example 6

[0071] The difference from Example 2 is that the preparation method of the detergent builder includes the following steps:

[0072] S1. After acid washing and water washing, the shells are dried, crushed, passed through a 150-mesh sieve, and calcined at 1000℃ for 5 hours to obtain porous calcium carbonate.

[0073] S2. Disperse the porous calcium carbonate in an aqueous sodium alginate solution, then add it dropwise to an aqueous calcium chloride solution at a rate of 1.5 mL / min. Let it stand for 1.5 h, filter, wash the solid phase, immerse it in a 0.5 mol / L chloroacetic acid solution, and adjust the pH to 8 with a 0.1 mol / L sodium hydroxide solution. Let it stand and solidify for 10 h, then remove it, wash it, and dry it to obtain the detergent additive. The ratio of the porous calcium carbonate, the aqueous sodium alginate solution, and the aqueous calcium chloride solution is 1.16 g: 100 mL: 6 mL; the mass fraction of the aqueous sodium alginate solution is 5%; and the concentration of the aqueous calcium chloride solution is 15 g / L.

[0074] Comparative Example 7

[0075] The difference from Example 2 is that in the preparation process of the detergent additive, only an aluminum source is added in step S1.

[0076] Comparative Example 8

[0077] The difference from Example 2 is that in the preparation process of the detergent additive, only a zinc source is added in step S1.

[0078] Performance testing

[0079] Eleven PVC test pieces with dimensions of 50mm×50mm×2mm were selected to ensure that the surface was free of scratches and initial oil residue.

[0080] Simulated composite oil stain: According to the actual production scenario, dioctyl phthalate, a commonly used plasticizer for PVC, is mixed with industrial dust (particle size 5-50μm) at a mass ratio of 3:1 and stirred evenly to make simulated oil stain.

[0081] Oil stain application: Use a pipette to take 0.1g of simulated oil stain and apply it evenly to the surface of each PVC test piece. Let it stand at room temperature for 24 hours to allow the plasticizer to fully simulate precipitation and adhere to the dust.

[0082] Weigh each test piece using an electronic balance to determine its initial mass (M0) and record the data.

[0083] The surface of the specimen was photographed under a stereomicroscope to capture the state of oil stains and the initial images were preserved.

[0084] The PVC test pieces were ultrasonically cleaned using the cleaning solutions prepared in Examples 1-3 and Comparative Examples 1-8, respectively. After cleaning, the surface moisture of the test pieces was dried, and the final mass (M1) of each test piece was weighed using an electronic balance, and the data was recorded.

[0085] 1) Oil residue rate: Calculate the oil residue rate of each test piece = (M0-M1) / M0×100%, and take the average value of each group. The lower the residue rate, the better the cleaning effect.

[0086] 2) Adhesive tape peel test: The Tesa® 4657 adhesive tape is flatly pasted on the surface of the test piece, and then rolled with a 2kg weight 3 times. The tape is then quickly peeled off, and the oil residue on the tape surface is observed and graded as "no residue or slight residue (level 1), obvious residue (level 2), and severe residue (level 3)".

[0087] The test results are shown in Table 1 below.

[0088] Table 1

[0089]

[0090] As shown in Table 1, the cleaning solutions prepared in Examples 1-3 of this application have better oil removal effects compared with the comparative examples.

[0091] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. An ultrasonic cleaning process for plastic toy products, characterized in that, Includes the following steps: Immerse the plastic toys in the cleaning solution, apply ultrasonic cleaning, then remove them and rinse with water. Repeat the above operation to complete the cleaning. The cleaning solution includes surfactants, penetrants, sodium hydroxide, detergent additives, and deionized water; The detergent additive is a microsphere structure with a core formed by a composite of porous calcium carbonate and Al2ZnO4 crystals and a shell formed by cross-linking sodium alginate with calcium ions.

2. The ultrasonic cleaning process for plastic toy products according to claim 1, characterized in that, The mass ratio of the surfactant, penetrant, sodium hydroxide, detergent, and deionized water is 10-18:5-7:4-8:0.8-1.5:65.5-80.

2.

3. The ultrasonic cleaning process for plastic toy products according to claim 1, characterized in that, The ultrasonic power is 200-400W, and the ultrasonic frequency is 25-55kHz.

4. The ultrasonic cleaning process for plastic toy products according to claim 1, characterized in that, The surfactants include di(hydroxyethyl) laurylamine oxide, dodecyl glucoside, sodium dodecylbenzenesulfonate, and fatty alcohol polyoxyethylene ether AEO-3.

5. The ultrasonic cleaning process for plastic toy products according to claim 4, characterized in that, The mass ratio of di(hydroxyethyl) laurylamine oxide, dodecyl glucoside, sodium dodecylbenzenesulfonate, and fatty alcohol polyoxyethylene ether AEO-3 is 3-5:2-4:1-3:4-8.

6. The ultrasonic cleaning process for plastic toy products according to claim 1, characterized in that, The preparation method of the detergent additive includes the following steps: S1. Take aluminum source, zinc source and ethanol, mix them, disperse them by ultrasonication, put them into oleic acid, heat and stir them in an oil bath at 115-125℃, dry them, calcine them at 750-850℃, grind them to obtain composite powder. S2. After the seashells are acid-washed and water-washed, dried, crushed, sieved, and calcined at 1000℃, porous calcium carbonate is obtained. S3. Take the composite powder and porous calcium carbonate, mix them, disperse them in an aqueous solution of sodium alginate, then add them dropwise to an aqueous solution of calcium chloride, let stand, filter, take the solid phase, wash and dry to obtain the detergent additive.

7. The ultrasonic cleaning process for plastic toy products according to claim 6, characterized in that, In step S1, the ratio of aluminum source, zinc source, ethanol and oleic acid is 1.2-1.6g: 1-1.5g: 60-80mL: 50-60g.

8. The ultrasonic cleaning process for plastic toy products according to claim 6, characterized in that, In step S3, the ratio of the composite powder, porous calcium carbonate, sodium alginate aqueous solution, and calcium chloride aqueous solution is 0.22-0.32g: 1.04-1.28g: 100mL: 5-7mL.

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