Factors affecting solid surface casting process
1. Influencing factors in the process
1) Batching process
Pay attention to the accuracy of the addition of various raw materials in the process of ingredients. Because the addition of color paste will affect the color of the board, particles, fillers, topcoats will affect the key process parameters - the viscosity level, which is especially important for color, otherwise it can not meet the customer's requirements and lose the application value. The filler to be added is usually aluminum hydroxide, and the platen made by mixing with the up resin has an agate-like texture, and the color of the product after coloring is bright, which is favored by consumers.
2) Defoaming process
Since a large amount of gas is dissolved during the mixing of the ingredients, if the bubbles inside the product cannot be excluded, the quality of the product is affected, so the defoaming process is very important. Defoaming is divided into two steps: one defoaming and two defoaming. The first step is defoaming. The specific method is to vacuum in a vacuum agitating tank under the condition of a vacuum degree of 0.9 to 1 mpa. Under such a degree of vacuum, the microbubbles are difficult to discharge. In this process, the viscosity of the system will increase due to the stirring time and the reaction time, and the viscosity will affect the quality of the sheet. Too low a viscosity will cause the particles to precipitate, and too high a viscosity will cause the bubbles to be uncleaned, resulting in a large amount of pores after polymerization of the raw materials. The pouring process is a process of injecting a completely defoamed material into a mold under vacuum conditions, and in this process, attention should be paid to controlling the speed of the pouring and the speed of pulling the mold to avoid nucleation and color separation. In order to eliminate the air introduced during the dumping process, secondary defoaming is required. Secondary defoaming, vibrating frame vibration defoaming: the use of this method should pay attention to the amplitude, frequency and vibration time of the platform. The amplitude is too large to deposit the filler on the surface of the template, resulting in a resin lean, slow curing, small shrinkage, and exotherm. The temperature is low; the other side is rich in resin, fast curing, slow shrinkage, high exothermic temperature, and prone to warping. At the same time as the vibration of this section, the scraper is used to process the material just injected into the mold to a certain level, which is convenient for post-treatment.
3) Curing process The curing process is carried out in an oven. Controlling the temperature of the oven is the key, and the temperature of the environment is also an important factor affecting the production of artificial stone plates. Therefore, there is a certain difference between the set temperature of the oven in winter and summer. The temperature of the liquid in the winter is lower. The polymerization time is longer than that of the liquid material. Therefore, increasing the oven temperature can shorten the polymerization time (about 40 °C); summer temperature The high viscosity increases rapidly, and the indoor temperature and the oven temperature must be strictly controlled to prevent the quality of the sheet from appearing. The temperature of the sheet coming out of the oven can not reach the maximum heating temperature, otherwise the sheet will have quality problems such as bowing, cracking and moiré. The time of sheet polymerization should also be strictly controlled. Prematurely, the sheet will have a “watermark”. When the sheet is pressed with the platen glass, the sheet is not completely polymerized, and it is in the late stage of polymerization, which must overcome the pressure of the glass and overcome its own. Fine cracks appear in the internal stress.
4) Demoulding process
The demolding process is the process of removing the sheet from the oven and removing it from the mold. When leaving the mold, pay attention to observe whether the hardness of the sheet reaches the extent that it can be released from the mold. If the mold is too early, the mold will be damaged to a certain extent to reduce the life of the mold (made of FRP); if the sheet is too late, the sheet will be bent, so it will be applied. A certain external force forces it to shrink, and after the sheet is taken out, it is pressed with tempered glass, so that the flatness of the sheet is maintained to some extent.
2. Development prospects
With the continuous improvement of artificial stone production technology, an artificial stone market that can adapt to multi-directional, multi-functional and multi-purpose needs is facing the opportunity of development and expansion. The artificial stone products are from a single traditional product, and are facing two-color, multi-color, and mosaic. , ultra-thin, diversified development. Quartz granite in artificial stone has been available in products with a thickness of only 3mm. The artificial stone ultra-thin board can be fixed on the wall with light weight and ordinary adhesive, which not only saves transportation cost, but also saves and utilizes stone resources in a large amount. At the same time, the artificial quartz granite has the advantages of low radioactivity, corrosion resistance, weathering resistance, durability, high gloss and uniform color, which is unmatched by other architectural decoration materials. According to industry experts, natural stone and artificial stone in the next few years, a large market share of natural stone will give way to artificial stone, the success of microcrystalline stone is a good proof.
3, the conclusion
In summary, the manufacture of high-quality solid surface artificial stone is not a simple technology, but involves a variety of comprehensive knowledge, high technical content, must have a wealth of professional knowledge and practical experience, familiar with the curing mechanism, materials Performance, process control, in order to create newer, better products.
QuanZhou Neweco High Polymer Material Co.,Ltd.
Neweco is one of the leading unsaturated polyester resin manufacturers and suppliers,widely used in automobiles, ships, rail transit, wind power generation, pipe cans, heat and corrosion protection, building materials, stone repair, sanitary ware, artificial stone and other industries. Suitable for hand lay-up, spray, pultrusion, winding, molding, vacuum introduction / RTM, casting and other molding processes. Neweco Resin is committed to excellence and focuses on the application of composite materials to provide customers with comprehensive solutions.