In our work contact, most people don’t know much about glow in the dark powder. They don’t understand what luminous powder can be used for, and what effect can be achieved. Today this article will talk about the application of several aspects of luminous powder.
The luminous powder used in plastic products:
The plastics industry is one of the most-used industries in the application of luminous powder. It can usually use injection molding and other processes to produce plastic toys, crafts, zippers, hard hats, and other products with luminous effects. These plastic products with luminous effects can increase the safety, interestingness, energy-saving, and environmental protection of customers when they are used.
Below we introduce some instructions and precautions in details for luminous powder used in the plastics industry:
Generally speaking, it is reasonable for the final product to contain 10-20% of luminous powder (not absolute, only for reference), based on the final effect the customer wants to achieve and its own injection molding technical support. It is added according to the brightness that the final product wants to make. The higher the ratio of addition or the higher the brightness level of the added glow powder, the higher the brightness of the final product.
In the injection molding process, if the plastic materials we use are not highly translucent, this will also cause the luminous powder can not absorb light or emit light. Therefore, the plastic material should be as transparent and light-transmissive as possible, and the luminous effect will be better. The materials that can be injected are PP, PE, PVC, PU, PS, ABS, TPR, EVA, PMMA, nylon, etc.
When the injection molding is performed, the shape of the plastic raw material should be similar to that of the luminous powder. (Plastic powder mix with glow powder and plastic masterbatch mix with glow masterbatch) It is easier to mix evenly, and the dispersion of luminous powder in the final product will be better.
Very often, customers report that after buying glow in the dark powder and using it on plastic, they find that the brightness of the luminous powder is not as good as expected. Even it is not bright, and it becomes black. It is due to various reasons, for example, injection molding technology, injection molding machine, the temperature of the molten material may cause blackening. And one of the reasons for the low brightness of the luminous powder is that it may be exposed to acid and metal during use. All these reasons will cause the brightness of luminous powder to be greatly reduced. (The reason for injection blackening can be found in another blog of mine). Glow Technology has recently developed a special luminous powder for injection molding, which greatly reduces the possibility of blackening in injection molding. Please contact us for specific details.
The luminous powder used for printing:
It is to use luminous ink to print as needed, adding glow in the dark powder pigment into printing ink and print on clothing, carton products, or other materials. It is generally used for clothing or venue identification in special work occasions such as public security, transportation, fire fighting, stage performances, or for casual wear, children’s clothing, and interior decoration. For example, many building number signs are screen-printed to create a luminous effect. It can be used as a reminder at night, without power consumption, energy-saving, and environmental protection. All kinds of small animal patterns are better if the luminous effect is printed on the eyes of the animals. After the night, the eyes will shine, increasing the artistic charm of the fabric. For the plant pattern, it is possible to print the luminescent color paste on its small flowers or flower cores, and the effect at night is also very interesting.
There are many printing processes. We will talk about the most commonly used screen printing in luminous printing:
The first and most important point of screen printing is that the particle size of the glow in the dark powder must be smaller than the size of the mesh. Otherwise, the luminous powder cannot pass through the screen and affect the luminous effect of the final product;
Influencing factors of luminous effect and precautions
(1) The addition ratio of luminous powder in luminous ink should be about 20% -40% according to the weight. The higher the addition ratio can reduce the number of repeated printing to achieve a better luminous effect.
(2) According to different printing materials, we choose different types of transparent inks, such as printing metal materials, we must select metal-specific inks. such as printing PVC materials, we must select PVC-specific inks, the higher the transparency, the better the effect.
(3) If it is water-based ink, you need to use waterproof glow powder.
(4) If the substrate is transparent or dark, white ink can be printed as a base to improve the luminous effect.
(5) Selecting luminous powder with high brightness level can reduce the proportion of addition.
The choice of luminous powder
Luminous materials are required to be non-toxic, non-hazardous, non-radioactive, safe for the human body, and not harmful to the environment. At present, there are many types of luminous materials on the market. Short-acting luminous powders have low luminous brightness and short afterglow time, while rare earth-doped aluminate inorganic long afterglow luminous powders have strong energy storage. High luminous brightness, afterglow time can be up to 12 hours. It is a kind of material that is used a lot at present.
Glow in the dark powder for paint
Glow in the dark paint has a very high luminous intensity, Glow Technology’s long-lasting luminous paint can continuously emit light for about 12 hours.
It can be recycled for unlimited times, has a long service life, is non-toxic and harmless, does not contain radioactive elements, and is a new generation of environmentally friendly decorative coatings. It can be used on the ground, wall, indoor and outdoor, and has the advantages of strong abrasion resistance, mildew resistance and durability, and strong weather resistance. Luminous paint is composed of luminous powder and water-based paint. Glow powder’ quality and the proportion of materials added determines the brightness of glow paint. (For more details, check my other blog on WHY ISN’T MY GLOW IN THE DARK PAINT GLOWING?)
A typical application of luminous paint: (applicable to display night objects and back materials)
- Architectural decoration, interior decoration, lighting, painting, wall surface.
- Night object identification label, power switch, tool, or toolbox.
- Beautify business locations such as PUB, KTV, storefronts, large parties.
- Traffic signs, fire emergency escape system, military equipment, garden beautification.
- Clocks, buttons, field instruments or indicators, radios, cameras.
- Bicycles, locomotives, automobiles, body patterns and aluminum rings, steel rings.
- Fishing equipment, aquarium equipment, flags, stickers, toys.
- General ornaments, stunning image painting, ceiling beautification, etc.
The luminous powder used in ceramics:
The glow in the ceramics a product sintered in a high-temperature under restore environment. The reason for its luminescence is mainly due to the physical photoluminescence generated by the transition of the low-valent electronic energy level of the rare earth element therein. Sintered ceramic glass requires a high temperature in an oxidizing atmosphere. If the luminous powder is directly applied, it will be oxidized, and the rare earth element will be oxidized to become a high valence state. The function of luminous will be lost.
Therefore, there are only two ways to make luminous ceramics:
- The proportion of luminous powder is generally between 30% -50%. After mixing the luminous powder with some transparent paints, it is coated on the surface of the ceramic. There is no oxidation and sintering process in this way, so the luminous powder will not be damaged. However, due to the presence of paint, the original glazed effect of the ceramic is lost.
- Use luminous ceramic glaze. This luminous ceramic glaze is a special luminous product. In the low-temperature stage, the enamel is quickly liquefied to seal the luminous powder and no more prolonged contact with oxygen. So it can ensure the luminous effect to a certain extent. However, even for luminous ceramic glazes, the lower the sintering temperature, and the shorter the sintering time, the better the luminous effect. It is more suitable for building ceramics, such as wall tiles and waistline products.
Ceramics can be turned into luminescent ceramics by adding luminous powder. Each piece of ceramic has a different proportion of glow in the dark pigment, and it will have a different luminous effect.
After absorbing the light source, ceramics can also admire the embryonic shape of the artwork in the dark space. It greatly improves the appreciation value of the artwork itself so that the artwork has a higher interpretation.
The production of high-grade luminous ceramic products can be made into luminous patterns as required, and products with completely luminous surfaces can also be produced;
Attention should be paid to the firing process:
(1) The luminous powder should avoid strong friction with metal objects; otherwise, it will affect the luminous effect;
(2) Choose a low-temperature glaze that matches the porcelain blank, and control the temperature and time. If the temperature is too high, the luminous powder may decompose; too long time will affect the luminous effect.
The problem often encountered when firing finished ceramics is that bubbles appear. This problem is generally due to the existence of the combination of additives or the chemical stability of the molten block and the transparent glaze. The proportion can be changed, or the additives can be replaced. It can also add an anti-foaming agent to eliminate.
To determine whether ceramics can be made into luminous materials, the specific process must also consult professional glow in the dark powder manufacturers.
How to use the luminous powder in glass:
The application of glass is very similar to ceramics. The point to note is that the temperature should be controlled below 500 degrees Celsius, and low-temperature glass is the first choice.
If the glass is fired at a high temperature, remember not to pour luminous powder directly into a high-temperature glass water. The luminous powder will have a luminous effect. You can use a shaped glass blank that has not been completely cooled down and fixed to a large-diameter luminous powder on the surface And then coated with a layer of glass to make the effect of starlight glass.
From the above, it can be seen that luminous powder is widely used in the three major industries of plastics, paints, and inks. It is subject to temperature restrictions in ceramic tiles and glass and requires more technical adjustments. However, Glow Technology has continuously been improving the quality of the luminous powder. Continuous research will do its best to meet all customer needs.