No abstract

The development of 3D technology has brought opportunities and challenges to the footwear industry because people’s living standards have been improving due to economic development, and people have higher requirements for the design of fashion shoes and boots. The use of 3D printing technology in the design of fashion shoes and boots can enable faster molding of footwear products, enrich the shape of footwear, and meet people’s aesthetic needs for fashion shoes. In this paper, we firstly describe the advantages of 3D printing molding shoe models and then use 3D laser foot scanning and measuring instrument to scan and obtain the cloud map of shoe lasts and foot-related data. Secondly, we realize the digital management of shoe lasts by establishing the database of solid models. On this basis, we apply the technology of least squares support vector machine improvement algorithm to make partial modifications to the lasts according to the need to leave the appropriate helper and foot lining degrees. Finally, based on this technology, we apply the least squares support vector machine improvement algorithm technology to make partial modifications to the last shape according to the need for appropriate helper and foot lining degrees to realize the process of shoe last redesign. The last model and role model can also be produced by 3D printing technology, which can be used as a mold to facilitate the processing of the cut last 2D unfolding material for shoe and boot production later. Therefore, the article studies and analyzes the design and manufacturing process of digital shoe lasts based on individual foot shape and uses CAD/CAM technology to realize the digitalization of shoe last design.

A series of blend membranes were prepared by immersion precipitation phase inversion method using hydroxypropylcellulose and polyacrylonitrile as raw materials. The effects of casting conditions on membrane's characterization were studied. The properties of resulting blend membranes were that water flux decreased from 489 L·h -1 ·m -2 to 312 L·h -1 ·m -2 ; retention rate increased from 80.1% to 91.8%; and corresponding porosity presented increasing trend but changed little within the range of casting solution concentrations from 10 wt % to 16 wt %. The greater the mass fraction of HPC in casting solution, the greater the water flux of blend membranes. Prolonging the atmosphere exposing time, water flux increased from 268 L·h -1 ·m -2 about 20s to 372 L·h -1 ·m -2 about 60 s, then decreased to 340 L·h -1 ·m -2 about 75s. In addition, retention rate decreased from 91.2% to 81.3%. Porosity tend to decrease but changed a little. With the coagulation bath temperature rising, water flux of blend membranes increased from 306 L·h -1 ·m -2 about 20 0 C to 429 L·h -1 ·m -2 about 35 0 C, and corresponding retention rate decreased from 87.9% to 82.5%, porosity decreased from 80.23% to 68.26%.

No abstract

In order to improve the dyeing fastness of indigo plant dyes for leather, save the cost of dyeing and reduce the environmental pollution in the dyeing process, the appearance quality is improved by improving the traditional indigo dyeing method. In this study, we try to use indigo acid environment to dye vegetable tanned leather to avoid the damage of basic environment to leather in the process of indigo vat dyeing. The single factor and orthogonal experiments of indigo natural dye dyeing vegetable tanned leather were carried out with the amount of iron medium, indigo dye, dyeing temperature and pre mordant dyeing time as experimental parameters, and the dyeing effect was evaluated with the K/S levels and color fastness as measurement indexes. The results showed that the concentration of iron powder was 10g / L, the pre mordant dyeing time was 25 minutes, the concentration of indigo was 16 g / L, and the dyeing temperature was 35 °C; the vegetable tanned leather after dyeing had better K/S levels, dry wet friction and tensile strength, but the light fastness needs to be further improved.