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CN-117565387-B - Processing step and method of coating process TPU

CN117565387BCN 117565387 BCN117565387 BCN 117565387BCN-117565387-B

Abstract

The invention relates to the technical field of 3D printing, in particular to a processing step and a processing method of a coating process TPU. The invention utilizes the post-treatment process of the forming part to treat the forming part, thereby not only improving the FDM printing speed by 3-4 times, realizing the successful printing of complex models which cannot be realized in the FDM printing process of TPU, but also breaking through the color flexibility which can be printed, greatly increasing the interlayer binding force after the forming part is treated, and ensuring the surface effect to be equivalent to the fineness of the SLA surface.

Inventors

  • FU WENJUN
  • ZHANG PU
  • HAN MINFENG
  • ZHU TAO
  • He Dudu
  • ZHANG XIAOJUN

Assignees

  • 徐州唯佳新材料科技有限公司
  • 武义斯汀纳睿三维科技有限公司

Dates

Publication Date
20260512
Application Date
20231115

Claims (5)

  1. 1. The processing method of the coating process TPU is characterized by comprising the following processing steps: s1, preparing a printing wire coating material, wherein the printing wire coating material mainly comprises 80 parts of PVB powder, a methanol solution, a DMF solution, a butanone solution and TPU polyurethane particles, and the concentration of the methanol solution is more than 95%; The specific steps in the step S1 are as follows: S11, stirring PVB powder to fully dissolve the PVB powder in a certain amount of methanol solvent to form a methanol solution of PVB, and preparing a solution I; S12, mixing 70% of DMF solution and 20% of butanone solution according to percentage to form a mixed solution, and adding 10% of TPU polyurethane particles to dissolve the TPU polyurethane particles in the mixed solution to prepare a solution II; s13, mixing the solution I and the solution II obtained in the step S11 and the step S12 according to a mass ratio of 8:2, and obtaining a solid substance through an evaporation treatment process; S14, granulating the solid substance obtained in the step S13 to obtain PVB polymer for later use; s2, preparing a special TPU raw material, which mainly comprises TPU64D, poly (adipic acid)/butylene terephthalate (PBAT), polycaprolactone, polyvinyl alcohol, plasticizer dibutyl phthalate, a silane coupling agent and allyl polyoxyalkyl epoxy ether, mixing, granulating and forming to obtain a TPU polymer for later use; s3, carrying out wire drawing treatment by using single-screw wire drawing processing equipment, taking the PVB polymer prepared in the step S14 as an outer layer material, taking the TPU polymer prepared in the step S2 as an inner layer material, and extruding and processing the PVB polymer into 3D printing wires by using concentric co-extrusion special processing equipment, wherein the diameter of the 3D printing wires is 1.75mm; s4, printing into a product by utilizing a three-dimensional forming technology of an FDM3D printing process to obtain a formed part of the product; s5, performing secondary treatment on the formed part, and obtaining a TPU additive 3D printing product; the specific steps in the step S5 are as follows: s51, soaking the molded part in alcohol or methanol solution for 10-20 minutes; s52, taking out the molded part from the solvent, and fumigating for 30-40 minutes by using an alcohol fumigation process to remove the solvent on the surface of the molded part.
  2. 2. The method of claim 1, wherein the viscosity of the second solution in the step S12 is controlled to be 0.0006-0.0008mPa.
  3. 3. The method for processing the TPU by the coating process according to claim 1, wherein in the step S2, the following mass ratio is adopted: 60-80 parts of TPU64D, 5-15 parts of poly (butylene adipate/terephthalate) (PBAT), 6-8 parts of polycaprolactone, 1-10 parts of polyvinyl alcohol, 2-6 parts of plasticizer dibutyl phthalate, 1-3 parts of silane coupling agent and 3-10 parts of allyl polyoxyalkylene epoxy ether.
  4. 4. A process for preparing TPU by coating according to claim 1, wherein the FDM printing speed in step S4 is 10-12mm3/S per volume.
  5. 5. The method of claim 1, wherein the step S51 is performed by ultrasonic equipment simultaneously.

Description

Processing step and method of coating process TPU Technical Field The invention relates to a processing step and a processing method of a coating process TPU, and belongs to the technical field of 3D printing. Background With the continuous development of the 3D printing industry, 3D printing is more and more close to people's life, and at present, 3D printing shoes printed by utilizing an SLA single-component forming process are crazy and crazy to catch up and hot pin, but shoes printed by SLA are influenced by double components, and only shoes with special designs and single-color products can be printed. With the continuous development of FDM, shoes printed by special TPU are now appeared, but the shoes have not been developed because of the influence of low printing speed, limited molding shape and the like. With the improvement of the printing speed of the FDM technology and the maturity of the technology in 2023, the shoes with colorful TPU can be printed at present, but the main defects of TPU in FDM molding according to market feedback are that the speed is low, the interlayer bonding force is poor, the surface fineness is not enough and the like, so the shoes cannot be applied. The invention can realize the printing of multi-color shoes and the direct forming of various wearable products, such as bags, watchbands, toys, flexible products and the like. Disclosure of Invention The invention aims to provide a processing step and a processing method of a coating process TPU, wherein a post-processing process of a formed part is utilized to process the formed part, so that the printing speed of FDM printing conventional TPU is improved by 3-4 times, colorful flexible printing is realized, the interlayer binding force is greatly increased after the formed part is processed, the surface effect is equivalent to the surface fineness of SLA, the process breaks the limitation that 3D can only print specific designs, the printing cost is greatly reduced, the efficiency is improved, and more importantly, printed objects can be directly worn. In order to achieve the above purpose, the main technical scheme adopted by the invention comprises the following steps: A processing method of a coating process TPU adopts the following processing steps: s1, preparing a printing wire coating material, wherein the printing wire coating material mainly comprises 80 parts of PVB powder, a methanol solution, a DMF solution, a butanone solution and TPU polyurethane particles, and the concentration of the methanol solution is more than 95%; S2, preparing special TPU raw materials, mainly comprising TPU64D, poly (adipic acid)/butylene terephthalate (PBAT), polycaprolactone, polyvinyl alcohol, plasticizer dibutyl phthalate, silane coupling agent and allyl polyoxyalkyl epoxy ether, mixing, granulating and shaping to obtain TPU polymer for later use; S3, carrying out wire drawing treatment through single-screw wire drawing processing equipment, wherein the processing equipment and the process are the prior art, see patent (CN 114752196A 2); s4, printing into a product by utilizing a three-dimensional forming technology of an FDM3D printing process to obtain a formed part of the product; S5, performing secondary treatment on the formed part to obtain the TPU additive 3D printing product. Preferably, the specific steps in S1 are as follows: S11, stirring PVB powder to fully dissolve the PVB powder into a certain amount of methanol solvent to form a methanol solution of PVB, and preparing a solution I; S12, mixing 70% of DMF solution and 20% of butanone solution according to percentage to form a mixed solution, and adding 10% of TPU polyurethane particles to dissolve the TPU polyurethane particles in the mixed solution to prepare a solution II; s13, mixing the solution I and the solution II obtained in the step S11 and the step S12 according to a mass ratio of 8:2, and obtaining a solid substance through an evaporation treatment process; s14, granulating the solid substance obtained in the step S13 to obtain PVB polymer for later use. Further, the viscosity of the second solution in the step S12 is controlled to be 0.0006-0.0008mPa.s. Preferably, in the step S2, the mass ratio is as follows: 60-80 parts of TPU64D, 5-15 parts of poly (butylene adipate/terephthalate) (PBAT), 6-8 parts of polycaprolactone, 1-10 parts of polyvinyl alcohol, 2-6 parts of plasticizer dibutyl phthalate, 1-3 parts of silane coupling agent and 3-10 parts of allyl polyoxyalkylene epoxy ether. Further, in the step S3, the PVB polymer prepared in the step S14 is used as an outer layer material, the TPU polymer prepared in the step S2 is used as an inner layer material, and the 3D printing wire is processed by concentric coextrusion, wherein the diameter of the 3D printing wire is 1.75mm. Preferably, in the step S4, the FDM printing speed is 10-12mm3/S per unit volume, because the conventional hardness of the TPU is 95A, the printing speed is relatively soft, the pr