April 22, 2010- Extruded PVC profiles are laden with multiple attributes like strength, toughness, rigidity, resistance to heat and chemicals, resistance to abrasion and weathering, glossy looks and economy. All of these properties make extruded PVC profiles and products, highly usable and demanded in a number of critical industry applications. Variety of industries like the building and construction industry, electrical industry, agricultural industry, fire fighting equipment manufacturing industry, AC and refrigerator industry, etc. - use PVC profiles or vinyl profiles, for many small and big essential applications.

The consumer industry witnesses heavy usage of extruded vinyl profiles due its ability to be extruded in intricate and complex profiles, abrasion resistance, cost factor and above all the high gloss characteristic. Consumer industry applications often call for a focus on good looks and beauty in the final application on an extruded profile. To ensure perfect PVC gloss in extruded profiles and products, the manufacturers should try to retain maximum gloss in the profiles. There are several industry and procedural factors that affect the gloss levels of PVC profiles. Let's have a closer look at what are the factors that control the extruded PVC profiles' gloss levels.

Gloss is nothing but a visual impression that depends on the amount of light reflected. More the light reflected, more the gloss. For more scattering or reflecting of light the surface of the profiles should have a microscopic structure that is not too fine to absorb the light. Rougher surfaces appear more glossy as compared to finer surfaces because of their higher light reflecting ability.

The reflectivity of any profile depends on the surface and the surface structure depends on a number of industry factors critical to an extrusion process. Some of the important factors that affect the reflective index of the surface structure are:

• Melt Strength
• Melt Formulation

Controlling the gloss of extruded PVC profiles requires control on the melt formulation and the melt strength. Melt strength varies from with the melt temperature, degree of fusion, molecular weight and many other formulation and procedural factors. Formulations with low melt strength often display low extruded profile gloss. It is the stress developed in the surface melt layer at exit point of the die and the response of the material to this stress level that affect the down stream state of the melt and finally determine the surface finish. High molecular weight allows for higher melt strength yielding highly glossy surface structures.

Other factors that affect the gloss and shine of the PC extruded profiles are: the extrusion die design, surface texture of the die and temperature of the die lip. Taking all these key factors in control allow s a control in the gloss levels of vinyl profiles.