Due to the different objects of Back to school Stationery, the style of stationery for students of different ages is also very different. The School Stationery for primary school students is mostly cartoon stationery series, while the stationery for middle school students and college students is mainly practical, and has been inclined to office stationery series. School Stationery,School Stationery Wholesalers,Stationery Set,School Supplies NINGBO MACEY EDUCATION PRODUCT CO.,LTD , https://www.maceycreative.com
After rapid development in recent years, this technology has reached a fairly mature application stage. Many ink production companies have begun to provide high-quality cement system products for various printing companies.
Below we will mainly introduce the application of pearlescent pigments in water-based ink systems, and how to deal with some related issues.
Second, the use of pearlescent pigments Titanium pearlescent pigments can be used in water-based ink system surface pearl interference type gloss or metallic luster, and will not produce technical problems.
Such pearlescent pigments consist mainly of platelet-shaped mother particles and a thin layer of metal oxide coated on them. The metal oxide film has a high optical refractive index (Np=2.5-3.0), and mica optics. The refractive index is relatively low (Np=1.5), see Figure 1.
As shown in Figure 1, the incident light is split into two paths on the surface of the pearlescent pigment, and the mirror-reflexive imported vehicle is refracted all the way to the interior of the pigment. The light has a different refractive index in the process of passing through the front material. Reflection and refraction occur at the interfaces between the two substances. It is this multiple reflection phenomenon that has led to the pearl-like iridescent luster.
From a productive point of view, there are three basic ways to create splendid, well-crafted colors:
One is to control the thickness of the transparent titanium dioxide coating deposited on the mica substrate. In this way, the part of the light reflected from each of the boundary cloths will have optical interference with each other due to the different optical paths. The color of the interference light we observe is determined by the thickness of the titanium dioxide coating.
The use of additional, optically absorptive metal oxides (such as ferric oxide or chromium oxide) in combination with the original interference layer results in correspondingly golden and green pearlescent effects.
The third is to deposit a high optical index and an optically absorptive metal oxide (such as ferric oxide) directly on the mica flakes and to control the thickness of the coating. The pigment thus obtained can perfectly and simultaneously surface optical interference and optical absorption effects, so that non-metallic pigments create the luster of metallic pigments.
It should be mentioned that pearlescent pigments can be supplied in different particle sizes, which is of great importance to the user of the product color. The reason for this is that the different particle sizes of the pigments determine the light and color effects of the product, from delicate matt effects to pearlescent luster, to flickering luster. In addition, the particle size determines how pearlescent light can be obtained. Han Ze. Fine pearlescent pigments have better hiding power than particles.
Pearlescent pigment is an inorganic pigment that is non-flammable, non-explosive, and electrically insulating. Even for diluted acid, salty solutions. Pearlescent pigments are also stable. Neither the organic solvent nor the water (which is particularly important here) has no effect on the pearlescent pigments. Like in polymer systems, pearlescent pigments can be easily dispersed in the two above-mentioned fractions.
The maximum temperature that the pearlescent pigment can withstand is 800 degrees Celsius, and it can meet the general requirements of ink making and printing drying. Its chemical inertness and extremely low heavy metal content make it very safe for the environment.
Because the interferential multiple reflection is an important light and color representation of pearlescent pigments, it is fundamentally different from conventional absorption/scattering pigments or totally reflective metal pigments, so it is defined as a third pigment.
Third, in the combined use of pearlescent pigments in water-based ink systems, there are two basic rules to note:
1. It is very important for the transparency of the ink binder system. Because of the basic characteristics of transparency, pearlescent pigments can produce pearl luster. The ink connecting material working medium should also have good transparency, otherwise the pearl luster will be significantly weakened even if it is not completely covered. (To be continued)
Student Stationery Set covers a wide range. According to the characteristics of stationery itself, it can be roughly divided into the following four categories:
1. Writing stationery for students. For example:
Pencils, automatic pencils, pencil refill, watercolor pens, whiteboard pens, neutral pens, ballpoint pens, oil pens, pens, crayons, etc.
2. Modified stationery for students. For example:
Correction tape, correction fluid, eraser, etc
3. Storage stationery for students. For example:
Pencil bag, pencil case, file folder, excersice book,document file, etc.
4. Tool stationery for students.
Pencil sharpener, liquid glue, glue stick, ruler, compass, utility knife, scissors, book cover, etc.
I. Introduction For many years, the iridescent pearlescent effect has been loved by people, and the field of application has become more and more extensive. But so far, most printing inks and paint coatings have always contained high concentrations of volatile organic solvents. In recent years, environmental protection by the steam gradually become the focus of modern industry, various governments have issued relevant regulations (such as the United States RULE 66 and Germany's AT-LUFT), requiring substantial reduction in the content of organic solvents in industrial products . This makes the majority of industrialized countries must consider how to improve the existing process to meet environmental protection requirements. The printing inks and coatings industry in the Western countries is one hundred countries to the above standards, and the measures taken are to replace the existing organic solvent systems with water-based systems.