No matter which of the above observation methods is used for the PVC plastic box, the printed matter should be placed in the middle of the light source as much as possible to reduce the influence of the external light source. The most important thing is that when it is necessary to compare the colors of two or more items, try not to superimpose them and watch them. It is best to discharge them under the light source.

1. Use fluorescent lamp D65

The fine color discrimination in PVC plastic box production requires that the lighting source has a real daylight spectrum distribution (including UV radiation and spectral radiation), and the fluorescent lamp D65 approved by the International Commission on Illumination (CIE) can perfectly imitate real daylight.

2. Light source characteristics

The illumination range of the light source is between 750 and 3200 lux, the color rendering index is >90, and the uniformity is >80%.

3. The background color requirements

Obvious color is a subjective feeling, so comparing colors in different backgrounds can produce different results. Therefore, the background color of all PVC plastic boxes is defined as Neutral Grey with a Munsell value of 6-8.

4. The requirements of environmental factors in color discrimination

Try to block all the extraneous light that may be shining on the detector. If the window is in the field of view, it should be equipped with gray curtains, so the color discrimination in the darkroom is the most ideal.