fényállóságot

Fényállóság, often translated as lightfastness, refers to the resistance of a material, typically a pigment, dye, or plastic, to fading or degradation when exposed to light. This exposure can be from natural sunlight or artificial light sources. Materials that are highly lightfast will retain their color and integrity for extended periods under illumination, while those with poor lightfastness will show a noticeable change in hue, darkening, or becoming completely bleached over time.

The degree of lightfastness is a crucial factor in many applications, particularly in the art world, where artists rely on pigments that can withstand light exposure to ensure the longevity of their creations. In textiles, lightfastness determines how well fabrics retain their color when worn or displayed outdoors or near windows. For plastics and coatings, lightfastness is important for outdoor furniture, automotive parts, and building materials, preventing premature discoloration and deterioration.

Various testing methods are employed to quantify lightfastness. A common system is the Blue Wool Scale, where numbered standards are exposed to light alongside the material being tested. The number indicates the degree of resistance, with higher numbers signifying greater lightfastness. Other scales and standardized tests exist, often specific to particular industries, to assess the durability of color under light exposure. Understanding and controlling lightfastness is essential for ensuring the quality and lifespan of many consumer and industrial products.