To answer your query, we have to discuss light. This will not be an easy thing to do. About 100 years ago, the world’s smartest scientists even argued about what light really is. And they argued for many years.
Light is definitely a bunch of tiny things that scientists call “photons”. These little things can travel unbelievably quickly.
How rapidly? Well, imagine this: photons can go around the total world more than seven times in just one second.
When these photons reach our eyes, we see them as light. The more photons there are, the brighter the light.
Photons can are available all the colors of the rainbow. In addition they hold energy which can flip into heat. This is why it feels warm when the sun shines.
But, not all light is the same. Blue and violet photons each have more energy than red ones, for example.
Now here is a weird thing: there are some types of light which can be invisible!
For example, ultraviolet (UV) light, which has even more energy than blue and violet light, is invisible.
Sunlight comprises a few of this highly effective UV light. Because it has so much energy, it could cause loads of damage, like sunburn, in case you get too much of it on your skin.
Another invisible type of light is infrared light. Infrared means “less than red”, so this light has even less energy than red light.
Making paint glow
Many light sources, like the Sun or an old light bulb in your toilet, glow because they are really hot. Regular glowing, like that of the Sun and a light bulb, requires objects to be really sizzling for us to see it.
As you already know, you may see glow-in-the-darkish paint, however in case you touch it, it’s just as cold because the bedroom wall. So, the glowing of the paint must be totally different to the glowing of a light bulb.
The paint has a particular type of glowing called “luminescence” and it can solely be created from a couple of types of material. One such materials is what scientists call “luminescent phosphors”, and this is what makes your paint glow. Scientists make luminescent phosphors within the lab by mixing special chemical substances collectively, after which add them to the paint. The paint is then sold to factories and producers who put it on toys, stickers, and even inside colouring pens.
While some things glow all the time, like the sun, glow-in-the-dark paint should be “told to glow in the dark paint“. Just like your parents need to cost their phones every evening to make them work, these supplies must be “charged” earlier than they start glowing.
In fact, the charging of your glow-in-the-darkish paint is done by other types of light. The invisible UV light with lots of energy can charge the particular phosphors in your paint and make it glow in your bedroom at night.
There are different types of glow-in-the-darkish paint. One type will be charged through the day and might glow for hours at midnight at night. The charging that happens throughout the day, for example by sunlight, is stored within the paint for some time, just like in the battery of a phone.
This type of paint is called phosphorescent. The other type, called fluorescent paint, solely glows while an invisible UV light is turned on to charge it.