What are the common reasons for poor quality of PU stone
Poor quality of PU stone is usually caused by various factors such as raw materials, production processes, formula design, and quality control. The following is a specific introduction:
Raw material issues
Poor resin quality: Polyurethane resin is the core component of PU stone, and its quality directly affects product performance. If inferior resin is used, there may be problems such as unreasonable molecular weight distribution and low purity, which can lead to a decrease in the strength, toughness, weather resistance, and other properties of the product. For example, PU stones made of inferior resin may experience cracking, deformation, and other issues in a short period of time.
Unqualified fillers: To reduce costs, poor quality fillers such as calcium carbonate with low purity and uneven particle size distribution are used, which can affect the physical properties of PU stone. Fillers with high impurities may weaken the bonding force between the resin and the filler, resulting in a decrease in the hardness and wear resistance of the product, as well as uneven color and rough surface on the appearance.
Poor pigment quality: If low-quality pigments are used in the production process, the stability and durability of the color may not be guaranteed. This type of PU stone is prone to fading and discoloration after a period of use, which affects its decorative effect.
Production process issues
Uneven mixing and stirring: During the production process, various raw materials need to be thoroughly mixed and stirred to ensure uniform distribution of ingredients. If the mixing is not sufficient, it will result in inconsistent performance of various parts of the product, with some areas having high strength and others having low strength, which can easily lead to local damage.
Improper curing process: The curing process is crucial for the quality of PU stone. If the curing temperature and time are not accurately controlled, it may lead to incomplete or excessive curing. Incomplete curing will result in insufficient product strength and poor wear resistance; Excessive curing can make the product brittle and reduce its impact resistance.
Mold quality and usage issues: The accuracy and surface quality of the mold can affect the appearance and dimensional accuracy of PU stone. If the mold itself has defects, such as uneven surface and wear, the produced product may have surface defects, dimensional deviations, and other issues. In addition, excessive use and improper maintenance of molds can also lead to a decrease in product quality.
Unreasonable formula design
Imbalance in component ratio: The proportion of various raw materials plays a crucial role in the performance of PU stone. For example, the ratio of resin to filler is not appropriate. Excessive filler can reduce the toughness and bonding strength of the product, while excessive resin may increase costs and lead to excessive shrinkage of the product. Similarly, inaccurate dosage of additives can also affect certain properties of the product, such as insufficient plasticizer dosage, which may result in insufficient flexibility of the product.
Lack of functional additives: In order to improve the performance of PU stone, it is usually necessary to add some functional additives, such as anti UV agents, anti mold agents, etc. If these additives are not properly added to the formula, the product's performance in terms of weather resistance, mold resistance, and antibacterial properties will be greatly reduced, and it is prone to aging, mold growth, and other problems in outdoor or humid environments.
Weak quality control links
Lack of strict testing standards: If a company does not establish a complete and strict quality testing standard, or if the testing standard is lower than the industry standard requirements, it cannot accurately screen out unqualified products. For example, incomplete physical performance testing items and insufficient testing accuracy for products may result in some PU stones that do not meet performance standards entering the market.
Incomplete inspection process: Even if there are inspection standards, if the inspection process is not standardized and rigorous, it is difficult to ensure product quality. For example, sampling testing is not scientific, and the sample cannot represent the quality status of the entire batch of products; Or the lack of real-time monitoring during the production process, which prevents timely detection and correction of quality issues, can lead to poor quality products leaving the factory.
