Cause delle differenze di colore nei prodotti stampati a iniezione
Color differences in injection molded products are a common problem that can affect the overall appearance and consistency of the parts, leading to product rejection. The main causes of color differences in injection molded products can be categorized into the following:
1. Material Factors
Material Variation: Different batches, manufacturers, or brands of raw materials may have inherent color variations. Even within the same batch, there may be subtle color differences between different parts of the material.
Color Masterbatch: Color masterbatch is a key factor affecting product color. Its quality and dispersion directly impact the final color of the product. Poor quality or unevenly dispersed color masterbatch can lead to inconsistent product color.
Additives: Certain additives, such as antioxidants and UV stabilizers, can absorb or reflect light, affecting the product's color.
2. Processing Factors
Injection Temperature: Injection temperature is a crucial factor influencing product color. Excessive temperature can cause plastic degradation and discoloration, while too low a temperature can lead to uneven color masterbatch dispersion.
Injection Pressure: Injection pressure affects plastic flowability. Excessively high or low flowability can result in product color differences.
Injection Time: Injection time determines the duration for which the plastic remains in the mold. Excessive injection time can cause plastic degradation and discoloration.
Cooling Time and Method: Cooling time and method influence the product's crystallization process, which in turn affects color.
3. Mold Factors
Mold Design: The design of the sprue, runners, parting lines, and other mold features can impact plastic flow and filling, affecting product color.
Mold Surface Roughness: Mold surface roughness influences plastic gloss, which can affect product color.
Mold Temperature: Mold temperature affects the plastic cooling rate, which can influence product color.
4. Environmental Factors
Workshop Temperature and Humidity: Workshop temperature and humidity can affect plastic's moisture absorption, which can impact product color.
Light Exposure: Light exposure can cause plastic to age and discolor, especially UV light, which accelerates plastic degradation.
