Routine tests for colored pencils include hand feel tests, monochrome tests, multi-color overlapping tests, as well as heavy metal content and fluorescent agents.
Feel test mainly observe the shape of the pen. If the pen is too thin, it is easy to get sore when handling the pen.
Monochrome color testing involves the following aspects:
Observe the thickness of the line, the pencil with fine lines is more suitable for overlapping colors and shaping details, while the rough line is not suitable for overlapping colors, and it is easy to appear white noise.
Check whether the pencil cartridge drops powder, fine powder particles of the pencil picture clean, easy to color, and coarse powder particles are easy to drop powder, the picture greasy.
Force the color block, observe the contrast between the color and the pen refill and the pen rod color, the color is close to the same color effect is good, and observe whether the color block is uniform, and the uniform pen quality is better.
Multi-color Overlay test includes:
Observe the transparency of each color layer of the overlapping color, good color lead transparency is high, the color is breathable, and the look is not dull.
When the color layer is calculated, the poor quality color lead may have problems such as slippage, soft and greasy, noise and dull after three times of color stacking.
heavy metal content and fluorescent agent detection are also important safety test items, if the content of these elements exceeds the national standard requirements, it may affect the normal operation of the child’s nervous system, leading to memory decline, growth and development restriction and other abnormal performance.
Therefore, in accordance with the “General requirements for the safety of student supplies” issued by the State, the whiteness of textbooks and exercise books used by students should not be greater than 85%, in order to avoid the use of papers with too much fluorescent whitening agent, which will emit different shades of blue light under ultraviolet light, indicating the addition of fluorescent agents.
