Aqueous dissociating abrasive cutting fluid used for cutting solar silicon wafer and its preparation method

Abstract

The invention discloses an aqueous dissociating abrasive cutting fluid used for cutting a solar silicon wafer and its preparation method. The aqueous dissociating abrasive cutting fluid comprises a synthetic polymer thickening agent, a non-ionic surface active agent, a dispersing agent, a defoaming agent and water. The aqueous dissociating abrasive cutting fluid has a moisture content reaching to more than 90 parts, the cutting fluid production cost is greatly reduced, but the performance is greatly improved, the cutting fluid has better dispersion suspension performance on SiC, the cutting fluid has better cooling and lubrication properties; aiming at the problem that a water base cutting fluid is easy to produce hydrogen in an on-line cutting process, the aqueous dissociating abrasive cutting fluid has targeted measures, greatly reduces the hydrogen production amount, makes the production more secure; and at the same time, and because of the low water content and high organic matter content, the aqueous dissociating abrasive cutting fluid is very low in COD (chemical oxygen demand) value, and is a green, environmental-friendly and new water base cutting fluid.

Description

technical field [0001] The invention belongs to the technical field of silicon wafer cutting, and relates to a cutting fluid, in particular to a water-based free abrasive cutting fluid for cutting solar silicon wafers and a preparation method thereof. Background technique [0002] With the continuous development of the solar photovoltaic industry, higher requirements are put forward for photovoltaic conversion efficiency and cost, which requires that every link of the photovoltaic industry must continuously improve the technical level. As silicon wafers are the core components of photovoltaic cells, the improvement of the quality of silicon wafers, the reduction of production costs and the greening of production will provide a stronger impetus for the development of the photovoltaic industry. [0003] Silicon wafer free abrasive wire cutting is to mix the cutting fluid with SiC and spray it between the steel wire and the silicon rod workpiece, so that the silicon rod produce...

AI Technical Summary

Problems solved by technology

This method is currently the most widely used silicon wafer cutting method, but there are still problems such as poor dispersion and suspension of the cutting fluid, high cost of the cutting fluid, poor cooling and lubricity of the cutting fluid, and serious environmental pollution.

The existing water-based cutting fluids used for free abrasive wire cutting of silicon wafers or the water content is still too low to achieve the purpose of effectively reducing costs, or the suspension dispersibility and lubricity are not enough, and few people mention water-based cutting fluids The problem of easy generation of hydrogen gas in the process of wire cutting

[0004] For example, the application number is 201210397124.9, the Chinese patent titled "Water-based cutting fluid for hard and brittle materials and its preparation method" and the application number is 201110176262.X, the invention title is "A water-based cutting fluid for silicon wafer cutting" The water content of the water-based cutting fluid mentioned in the Chinese patents is 40 parts or less, although the production cost is saved to a certain extent, but the range is not large, and the COD value of the cutting fluid is still high due to the low water content, and the It cannot be truly green and environmentally friendly; moreover, in the process of separating the waste mortar after cutting, the organic matter on the surface of SiC is not easy to separate, and the content of organic matter in the above two patents is very high, resulting in more organic matter adsorbed on the surface of SiC, further increasing Reduced the difficulty of waste mortar treatment

[0005] Secondly, the water content of the water-based cutting fluid disclosed in the application number 201110174484.8 and the title of the invention "a water-based wire cutting fluid for silicon wafers" has reached 89.95-98 parts, but the main component mentioned in it is poly Vinyl alcohol is easy to form a film on the surface of the machine, which will cause inconvenience to the stability and continuity of production

[0006] Furthermore, although the water-based cutting fluid in the US patent with the application number US13139046 and the invention name "Cutting Fluid Composition For Wiresawing" mentions the problem that the water-based cutting fluid will generate hydrogen during the cutting process, its suppression of hydrogen ability is still low

[0007] In view of the existing water-based cutting fluids, there are generally problems such as low water content, ignoring the hydrogen gas generated during the cutting process, and poor lubricity. The indicators of water-based cutting fluids cannot be comprehensively integrated, resulting in high production costs and high COD values ​​of cutting fluids. Severe pollution, serious damage to the surface of the silicon wafer after cutting, etc.