TPE Thermoplastic Elastomers: Are There Differences in Material Safety Between Dark and Light Colors?

TPE thermoplastic elastomer products are common in daily life, from baby teething rings to kitchen seals, and are closely related to our daily living. The safety of such materials naturally becomes a focal point of concern, and the question of “which is safer, dark or light-colored TPE?” often arises. In fact, color itself is not the key factor determining TPE safety; the underlying raw materials, additives, and manufacturing processes are the core factors. Why is that? Let's take a look at the analysis by the editor of Huizhou Zhongsu Wang.

1. The impact of raw material differences on safety

From the perspective of raw materials, the primary material for TPE thermoplastic elastomers is thermoplastic elastomer base materials such as SEBS and SBS. High-quality base materials inherently possess excellent chemical stability and safety. Whether they are made into dark or light colors, their base material safety properties remain consistent.

However, some manufacturers may use recycled materials or low-quality base materials in dark-colored TPE to reduce costs. Recycled materials may contain unknown impurities, aged components, or residual contaminants, which could affect safety. In contrast, light-colored TPE, due to its transparent or light color, makes impurities more easily detectable, so manufacturers are less likely to use recycled materials, indirectly leading to differences in safety between the two.

II. Impact of Additive Usage on Safety

The use of additives is a key factor affecting safety. Light-colored TPE thermoplastic elastomers have higher requirements for pigment purity, typically using high-purity, low-migration inorganic pigments or food-grade organic pigments. These pigments have extremely low heavy metal content and meet safety standards.

However, dark-colored TPE thermoplastic elastomers, such as black or dark brown, may use inexpensive carbon black or industrial-grade dyes. If the carbon black purity is insufficient, it may contain harmful substances like polycyclic aromatic hydrocarbons. Industrial-grade dyes may also have issues like heavy metal exceeding standards or residual volatile substances. Additionally, dark-colored TPE may add more stabilizers, plasticizers, and other additives to mask raw material defects. If the quality of these additives does not meet standards, it may also increase safety risks.

3. Impact of production processes on safety

Production processes also affect safety. Light-colored TPE thermoplastic elastomers, due to their lighter color, require stricter cleanliness standards in the production environment. Impurities must be avoided during processing to prevent issues with appearance and safety. Some manufacturers may relax process controls when producing dark-colored TPE, such as uneven mixing leading to localized excess additives, or inadequate control of degradation during high-temperature processing, resulting in harmful small molecules. However, reputable manufacturers apply uniform strict process standards to both dark-colored and light-colored TPE to ensure both meet safety standards.  

Therefore, determining the safety of TPE thermoplastic elastomer products cannot be based solely on color. A more reliable approach is to verify if the product has obtained relevant safety certifications, review the manufacturer's test reports, and prioritize brands with a good reputation. After all, whether dark or light-colored, only TPE that meets safety standards can truly be used with confidence.