Different packaging glossiness can have unexpected visual effects, greatly improving the quality of product packaging. The commonly used printing packaging glossiness effects are included in the following types, each of which can be achieved by using a gloss meter to measure the specific gloss of printed packaging:
(1) Pearlescent effect can be achieved by printing transfer in pearlescent ink. Pearlescent printing requires a certain pearlescent texture. Therefore, the content of pearlescent powder in the ink is generally not less than 30%. Pearlescent ink should also have certain thickness makes the pearl effect more obvious.
(2) Crystal gloss refers to the crystalline substance hidden on one side of the printed product or in the transparent ink layer. Under the change of the incident angle of the fluorescent lamp or light, it can produce a colorful and shiny special effect.
(3) Variable gloss printing refers to a printing process that uses special inks or materials to produce printed products. Under the mutable force of a certain energy, printed products can produce gloss changes. At present, it can be divided into two types of printing processes: thermochromic and photochromic.
(4) Metallic gloss printing should have some connection with iron printing process. In the process of iron printing, people have found that the more transparent ink is printed on tinplate that has been coated, polished and mirror-finished. The printed product can produce a glittering, translucent and magnificent effect, which feels very high-grade. Affected by this, due to the emergence of metal cardboard and anodized aluminum materials and vacuum aluminum plating technology, it has been cited in the field of paper and plastic composite packaging.
Gloss is a property of the object surface, which can be expressed by the surface's ability to produce specular reflection. The use of different materials and processing methods for product packaging will cause great differences in appearance gloss. If the gloss of the product packaging surface is uneven or there is a significant difference in gloss between different batches of product packaging, it will affect the overall appearance. We should use porfessional gloss meters to check the product gloss so that we can avoid obvious differences in packaging gloss.
Package gloss is mainly determined by surface refractive index and surface smoothness. When the refractive index of the packaging material is high and the surface is smooth, the specular reflection of the light meter is dominant, then the glossiness is high; otherwise, the diffuse reflection is dominant and the glossiness is poor. The composition and manufacturing process of packaging materials are the main factors affecting the surface gloss.
With the increasing requirements for the quality of PVC products, the requirements for most PVC products such as flat, regular appearance and good surface brightness have become the concern of manufacturers. The gloss of PCV products is an important index for evaluating product quality. Generally, a gloss meter is used for testing. Under the same formula, processing equipment and process conditions, the type or amount of additives was changed to produce PVC packaging samples of the same thickness for testing. At present, people who need to do the gloss testing of plastic packaging products use Linshang portable gloss meter.