The transparent texture of resin tableware is presented

Resin selection and the basis of transparent texture

Resin type: The transparency and texture of different types of resins vary significantly. Polystyrene (PS) resin has a high degree of transparency. Its molecular chain structure is regular and its crystallinity is relatively low, resulting in less light scattering within it and allowing most of the light to pass through, thus presenting a good transparent effect. It is often used to make tableware with high transparency requirements, such as some transparent cups and plates with a simple style. Polymethyl methacrylate (PMMA, commonly known as organic glass) has a higher transparency, approaching that of glass. Its molecular chains are highly flexible, with extremely low absorption and scattering of light. It is suitable for making tableware that requires an extremely transparent texture, such as the transparent display plates used in some high-end restaurants.

Resin purity: Impurities in the resin raw materials can seriously affect the transparent texture. Impurities can form scattering centers within the resin, causing light to scatter during its propagation and resulting in the tableware appearing blurry. Therefore, in the production process, high-purity raw materials need to be used and impurities should be removed through meticulous purification techniques. For instance, when manufacturing polycarbonate (PC) resin tableware, conducting multiple filtration and distillation treatments on the raw materials can effectively enhance the purity of the resin, thereby improving the transparency of the tableware.

The influence of molding process on the transparent texture

Injection molding: This is a commonly used molding method for resin tableware. During the injection molding process, the control of parameters such as temperature, pressure and injection speed is of vital importance. If the temperature is too low, the resin has poor fluidity and cannot fully fill the mold cavity, which will form flow marks, bubbles and other defects on the surface of the tableware, affecting the transparency. If the temperature is too high, it may cause the resin to decompose, generating impurities and also reducing the transparent texture. Pressure and injection speed also need to be precisely matched. Appropriate pressure can ensure that the resin fills the mold tightly, avoiding problems such as shrinkage cavities, while an appropriate injection speed can reduce the shear heat generated by the resin in the cavity and prevent local overheating that leads to a decrease in transparency. For instance, when manufacturing polypropylene (PP) resin tableware, by optimizing the injection molding process parameters, the surface of the tableware can be made smooth and the transparency can be significantly enhanced.

Blow molding: Mainly used for the production of hollow resin tableware, such as plastic water cups. During the blow molding process, the blow molding pressure and time can affect the uniformity of the wall thickness of tableware. Uneven wall thickness can cause inconsistent refraction and scattering of light during its propagation, thereby affecting the transparent texture. Appropriate blow molding pressure can make the parison expand uniformly, forming tableware with uniform wall thickness, ensuring that light can pass through smoothly and presenting a good transparent effect. At the same time, controlling the blow molding time well can prevent the parison from being overly stretched or understretched, ensuring that the shape and transparency of the tableware meet the requirements.

The post-treatment process enhances the transparent texture

Annealing treatment: During the molding process of resin tableware, internal stress is generated. This internal stress can cause the tableware to deform or crack during use, and also affect transparency. Annealing treatment involves heating tableware to a certain temperature, maintaining it for a period of time, and then slowly cooling it to rearrange the resin molecular chains and eliminate internal stress. For instance, for polyethylene terephthalate (PET) resin tableware, after appropriate annealing treatment, its transparency will be significantly enhanced, and the dimensional stability of the tableware will also be improved.

Surface polishing: The roughness of the tableware surface can affect the reflection and refraction of light, thereby influencing the transparent texture. Through surface polishing treatment, the roughness of the tableware surface can be reduced, allowing light to reflect and refract more regularly and enhancing transparency. Common polishing methods include mechanical polishing and chemical polishing. Mechanical polishing involves using a polishing wheel and polishing paste to rub the surface of tableware, removing tiny protrusions and scratches on the surface. Chemical polishing is a process that uses chemical reagents to corrode the surface of tableware, making it smooth. For instance, for some transparent resin lunch boxes, after surface polishing treatment, they will present a brighter and clearer transparent effect.

The influence of environmental factors on transparent texture and their responses

Light exposure: Prolonged exposure to sunlight may cause certain components in resin tableware to undergo photo-oxidation reactions, leading to molecular chain breakage or cross-linking, which results in the tableware turning yellow, becoming brittle, and reducing transparency. To reduce the influence of light, ultraviolet absorbers can be added to the resin. They can absorb ultraviolet energy and convert it into heat energy to be dissipated, thereby protecting the molecular structure of the resin from damage. For instance, adding ultraviolet absorbers to some transparent resin tableware used outdoors can effectively extend the service life of the tableware and maintain its transparent texture.

Temperature: High-temperature environments can cause the resin to soften, deform, and even decompose, affecting its transparency. However, a low-temperature environment may make the resin brittle and prone to cracking. Therefore, when using and storing resin tableware, it should be avoided to place it in extreme temperature environments. For example, do not place resin tableware beside a hot stove or in the freezer of a cold refrigerator.