Well, sometimes our possessions and paints really can change color, thanks in part to thermochromic ink technology. Thermochromic inks take advantage of thermochromism, which refers to materials that change their hues in response to temperature fluctuations. Still hate that lime green? Pony up for the right paint and on a warm day, it could morph from a Kermit the Frog hue into a more tolerable sunshine yellow.

Thermochromic inks first hit the mainstream in the 1970s, appearing in one of that era's lasting icons -- the mood ring, which supposedly used the wearer's body heat as a sign of his or her emotional state.

More recently, a microwaveable maple syrup bottle featured a thermochromic label that indicated when its buttery, delicious goodness was warm enough for your waffles. And some beer cans sport graphics that appear when their hoppy contents are cool enough to provide optimum refreshment.

Since mood rings, thermochromic inks have evolved at a steady pace. They're still used in all sorts of silly novelty items, but they have many useful and creative applications, too: thermometers, clothing, paint, drink containers, toys, battery indicators, plastic products of all kinds and much more.

There are numerous companies integrating these dynamic, eye-catching inks into their products. Doing so can help them grab consumers' attention and differentiate a brand from those that use old-fashioned inks with just one static hue. Paired with a clever bit of creativity, such products provide real visual wow.

Keep reading and you'll see how these crazy inks pull their chameleon tricks. Be ready -- your eyes in are in for a surprise.

Loco for Leuco (Dyes)

Liquid crystal-based TLCs are a temperamental bunch and rather difficult to incorporate into labels, clothes or other goods. Leuco dye inks, though, feature more durable chemistry that lets product designers employ these inks for all sorts of fun applications.

One of the most famous applications of leuco dyes is on cans of Coors Light beer. These cans feature a graphic of a mountain landscape next to the company's logo. At room temperature, the mountains appear white. Cool the can to drinking temperature (about 45 degrees Fahrenheit or 7 Celsius), though, and those same mountains turn a vivid, bright blue. As the beer warms in your hand, the graphic again shifts to its original white. This color change can happen over and over again.

As with TLCs, leuco dyes are also microencapsulated into tiny droplets that are only about 3 to 5 microns in size, which prevents them from reacting with or being damaged by other chemicals.

Usually, leuco dyes are colored when they're at a cool temperature. Then, as heat rises, they become translucent, which lets them reveal any colors, patterns or words that may be printed on an underlying layer of ink. In other products, leuco dyes can be blended with another color so that as temperatures change, a two-tone effect occurs. Mix blue with yellow, for example, and you have an ink that looks green at lower temperatures and yellow when heat rises.

It sounds a bit magical, but there's some basic science behind the way the inks work. The teensy capsules contain a colorant, an organic acid and a solvent. At lower temperatures the solvent remains in a solid state, keeping the colorant and acid in close proximity to each other -- and as a result, they reflect light and create color. As the solvent warms, the colorant and the acid separate and there's no visible color, which in turn exposes underlying inks.

Take your maple syrup bottle as an example. At room temperature, the bottle shows a picture of a tiny black microwave; when warmed, the black area fades, temporarily revealing the word "hot."

When it comes to temperature accuracy, leuco dyes are more ham-handed than TLCs, so you can't depend on them for applications where you really need a precise temperature reading. But leuco dyes can be integrated into all sorts of fascinating and amusing products.

chore of painting it all over again. You wish that the colors of the things in your life were as dynamic as life itself.

Well, sometimes our possessions and paints really can change color, thanks in part to thermochromic ink technology. Thermochromic inks take advantage of thermochromism, which refers to materials that change their hues in response to temperature fluctuations. Still hate that lime green? Pony up for the right paint and on a warm day, it could morph from a Kermit the Frog hue into a more tolerable sunshine yellow.

Thermochromic inks first hit the mainstream in the 1970s, appearing in one of that era's lasting icons -- the mood ring, which supposedly used the wearer's body heat as a sign of his or her emotional state.

More recently, a microwaveable maple syrup bottle featured a thermochromic label that indicated when its buttery, delicious goodness was warm enough for your waffles. And some beer cans sport graphics that appear when their hoppy contents are cool enough to provide optimum refreshment.

Since mood rings, thermochromic inks have evolved at a steady pace. They're still used in all sorts of silly novelty items, but they have many useful and creative applications, too: thermometers, clothing, paint, drink containers, toys, battery indicators, plastic products of all kinds and much more.

There are numerous companies integrating these dynamic, eye-catching inks into their products. Doing so can help them grab consumers' attention and differentiate a brand from those that use old-fashioned inks with just one static hue. Paired with a clever bit of creativity, such products provide real visual wow.

Keep reading and you'll see how these crazy inks pull their chameleon tricks. Be ready -- your eyes in are in for a surprise.

The Heat is On, The Color is Off

Thermochromic inks conjure their magic in different ways. Currently, there are two major categories of these inks: thermochromatic liquid crystals (TLCs) and leuco dyes.

Liquid crystals are exactly what their name indicates -- a substance that has many properties of a liquid crossed with structural elements inherent to crystals. Peer through a microscope at a liquid crystal and you'll see a fluid that exhibits evident textures.

Liquid crystals are dynamic. Their properties change depending on environmental conditions; TLCs exhibit different colors in response to temperature changes. At lower temperatures, these liquid crystals are mostly in a solid, crystalline form. In this low temperature state, TLCs may not reflect much light at all, thus, appearing black.

Apply warmth and increase it bit by bit, though, and you'll see the TLCs shift from black to just about every color of the rainbow. This happens because as temperature rises, spacing between the crystals changes, and as a result, they reflect light differently.

You can't just plop TLCs onto a product to make it change colors. The liquid crystals must first be microencapsulated into billions of tiny capsules that are just a few microns in size. This encapsulation process offers some protection for the TLCs and maintains their thermochromic properties.

Then, these capsules are blended with other materials and used in products, such as room thermometers. Hang the thermometer in a bedroom and you'll see a rapid change in color that indicates an accurate temperature.

Temperature accuracy is a strong suit for TLCs. Their color consistency means they can indicate heat levels to within a few degrees. However, TLCs are a touchy technology. Their performance can suffer with repeated exposure to UV light, water and chemicals. What's more, they require specialized equipment for proper integration into various products, and that equipment (as well as the TLCs themselves) often adds significant expense to a manufacturer's production costs.

Leuco dyes and inks, though, are a different story.

Glow in the dark powders have been around a while. The zinc sulfide type was developed way back in the early 1800's. These are still cool, but the longevity of glow is only around a half an hour at best. Within the last twenty years, glow in the dark powders have come a long way. A compound called Strontium Aluminate was developed and scientist added an activator called Europium and bang! You have a substance that glows up to 13 hours. I will not go into the details of how it stores and releases energy here, but I do want to cover how it works in an airbrush.

Glow in the dark powders come in 8 different colors. Red, White, Blue, Teal, Violet, Green, Yellow, and Orange. The yellow and orange are a yellow-green with added dyes to make them glow yellow or orange. The rest are their true colors. They can have many different daytime colors. The red, purple, blue, are white in the day light. The green and teal are an off white with a slight yellow green tint. The orange and yellow have like colors in the daytime. The white has a daytime color of white. These colors can differ from suppliers, and the colors listed are those of Glonation.com.

Glow times are 12 hours for the green, 8 to 10 for the teal and blue, 4 for purple yellow and orange. The red is half an hour and the white is around 10 minutes.

The powders also come in different mesh or grain sizes. For Spray Painting & Airbrushing I highly suggest using the finest mesh glow in the dark powder available. See the chart below.

· Smallest size 12-25 micron

· Medium size 25-55 micron

· Large size 55-100 micron

You will also get varying degrees of glow time from your glow paint depending on the size of the particles. The smaller the size, the less the glow time. But adding layers enhances the glow intensity.

This is the tricky part of Spray Painting & Airbrushing with glow in the dark powder; because it is grainy, it tends to clog the brush more often than just using airbrush paint.

Applications:

In addition to pain instrument, roads, machinery and equipment, fire equipment, air defense walkways and other safety signs and luminous watches and jewelry, this coating can be used for building decoration, warning signs, car license, military facilities.

Features:

After ultraviolet light or sunlight excitation, it is long luminous duration at night or in the dark ,which can be luminous than 20h, and not aging.It extends the life of the coating, and when it touches to the human body without toxic effects, improving their effectiveness and value.

Ratio of raw materials (weight)

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Water based photoluminescent coating

Produce procedure: 

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After the above raw materials were mixed, at room temperature stir 60min, and grind.

Raw materials of water based photoluminescent coating and weights are as follows: Water 400~500; alkaline earth aluminates 250~500; PVAC 250~450; 974 coalescent 10~20; 1124 dispersant 5~10; plasticizer 5~15; tributyl phosphate 5~10

Applications:

In addition to pain instrument, roads, machinery and equipment, fire equipment, air defense walkways and other safety signs and luminous watches and jewelry, this coating can be used for building decoration, warning signs, car license, military facilities.

Features:

As alkaline earth aluminates is used as photoluminescent pigment. After ultraviolet light or sunlight excitation, it is long luminous duration at night or in the dark ,which can be luminous than 20h, and not aging.It extends the life of the coating, and when it touches to the human body without toxic effects, improving their effectiveness and value.

But to get the real reflect chrome effect,It is really necessary for printers to test to determine how much pigment you want.

1. the ratio of copper powder in the ink is typically 10% -15% of the proportion ratio, the proportion of resin is 55%, the proportion of the diluent is 30%.

2.the ratio of aluminum silver in the ink is typically 10% -20% of the proportion ratio, the proportion of resin is 50%, the proportion of the diluent is 30%.

Another reason to ensure color consistency is difficult to arrange the pigment, especially stratified gold and silver powder ink. Metal flakes floating in the ink film surface, forms a lot of free open areas. (More coarse particle size of the color, the greater the desert to idle).

When copper powder aluminum silver inks is printed, printing materials selection is very hub.Because a lot of pores on the surface, with a penetration of exudative printing materials will absorb liquid transparent resin.Especially when the ink viscosity is low, the resin is absorbed, the pigment particles will remain on the surface of substrates. Less resin component, will result in rendering gray silver powder, and the gold powder is rendered brown.For screen printing, the pigment particle size is usually between 3 ~ 15μm.So if you insist on using aluminum manufacturing silver ink, then we must ensure that the aluminum powder is stored in a dry place with right temperature.At different premises, metallic pigment particles and binders after mixing, the shelf life of the ink is different, generally between a few hours to several months. Screen printing ink manufacturers are still ongoing efforts to refine gold and silver powder ink, so they use it more easily, producing stunning results.Ink pigments act as binders and adhesives to protect the ink dried film.

Silver ink is made of aluminum powder dispersed in a solvent and then braced oil binders made of.At this time the pigment particles will settle to the bottom of the ink film, greatly improving their adhesion. But because the particles at the bottom isn’t line up regularly,  the light needs to pass through the link material to enter the bottom surface of the particles to be able to be reflected at the expense of luster.Under comparison,in the presence of aluminum paste is relatively safe.All aluminum powder producers supply various forms of solvent-based, water-based and UVdrying inks compatible pasty pigment. The fact is that the fewer the number of paint, the better adhesion, , the more the average ink film, the more average means more smooth surface, the reflection function better, of course, the better the gloss.If you have no other choice but to use absorbent substrates, it is best to print one ink (like traditional transparent varnish), printing materials to seal the pores of the surface, and its gold and silver powder printing ink.Gold ink use in a certain percentage of copper zinc. Depending on the different ratio, gold redness or fluorescence can also be made of a transparent yellow ink and aluminum pigment. It is better to use gold ink gloss copper system, but in a long time, keeping the gloss is not bad, and chemical resistance and toxicity are quite good.Fine metal pigment particles at the time of transfer is more suitable, unlike those oversized particles required by increasing the mesh screen,fine pigment particles are at the expense of gloss.This is the reason that it is generally not recommended to use traditional printing spectrophotometer to measure gold and silver powder print.In most cases, the metal powder is sold as a screen printing ink sector, in the use of added binders.

1. pigment: silver pigment

2. Solvent: toluene, xylene, butyl acetate, 783, etc.

3. Resin: known as varnish or lacquer, which according to the type of material to be coated and fixed objects, such as for steel and transparent varnish.

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[Usage]

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(1)solvent dilution is added to silver pigment,the amount to just dilute silver, making silver uniformly dispersed better.

(2)Silver even after dilution, adding varnish to mix thoroughly. added amount of Varnish to just make the silver spray paint not open at the end better.

(3)Silver: diluent: resin ratio = 1: 3: 7 (weight ratio).This proportion is for reference only, the specific amount requested flexible changes in the practical application.Thin or thick resin has a great effect on this ratio.

[Remark]

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Pine fragrance, cyclohexanone, also used as a solvent, but such a toxic solvent, is not recommended.

(1)Ordinary copper powder have good floating performance, we recommend it is not necessary to add a wetting or dispersing agent, otherwise it will reduce its floating nature (metallic effect).

(2)If in order to deliberately adjust the floating performance powder, it can be appropriate to reduce its floating nature (adding 0.1-0.5% citric acid). But this would reduce the metallic effect.

(3)If you still can not obtain the desired optical effect by adjusting the application viscosity and drying time. That is, pigment particles failed to have better orientation.You can add a small amount of lubricant and surface leveling agent.

(3)In general, the performance of copper powder re-dispersed is good. If  precipitation is found, it can be added to <2.0% of the anti-settling agent or thixotropic agents, such as swelling disabilities, fumed silica in the formula.

Copper powder dispersion method

(1)join metallic pigments in a slow stirring, add to the gold powder several times 1:1 or 2:1solvent

(2)Stirring for about 15 minutes to a paste at low shear

(3)Join the oil required , stir mixture evenly

(4)Adjusted to the desired viscosity with a solvent

(5)To avoid flake powder particles in the dispersion process and reduce curl and break the optical effect, the best selection is disc blade mixer or dispersing machine

Bronze powder and finished storage

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Copper powder and their products should be stored at room temperature and dry conditions. The unused copper powder should be sealed immediately. Otherwise, due to prolonged exposure to copper oxide powder and deterioration in air.

(1)Avoid using nitrocellulose and epoxy resins.Because both will generate jelly react with copper; if we must choose two resins, they should be used whenever possible in a short time.

(2)Use low acid value (less than 3) of the resin if possible. The acid value of the resin system,the lower the better.

(3)Aromatic hydrocarbon and ester solvents helps to complete the hole wet and powder particles is sufficiently dispersed.Avoid using solvents and alcohols and ketones acidification incomplete lipid solvents.

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(4)Be sure to use high purity resin and solvent (low water content).If containing a small amount of water, it is recommended before adding pigment powder to use molecular sieve aerosilr972 or silosievea 4 to remove water.

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The use of physical and chemical methods in bronze powder-coated surface of organic and inorganic.It studied through different reagent-coated copper powder processing oxygen uptake in weakly alkaline aqueous medium,calculate the inhibition efficiency, and differential thermal analysis of the different treatment of copper powder coated antioxidant properties at high temperatures.For water-based gloss bronze powder of low status, the use of mechanical force chemical modifies surface of copper powder.It studied the influence of surface modification on copper powder in an aqueous dispersion of connecting compound, alignment and floating performance and analyzing its mechanism of action, exploring the relationship between the various properties, and surface treatment reagents optimized copper powder.

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The main findings are as follows:

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(1)root cause of aqueous copper powder  corrosion and hue change is due to the oxygen reaction takes place in a weakly alkaline aqueous solution.

Organic acids and SiO2 coated copper powder can effectively inhibit oxygen corrosion of copper powder. Citric acid, which can be generated with a metal chelate, is the best corrosion inhibition efficiency reaching 95.83%, followed by ascorbic acid 90.28 %.

(2)Salt and saturated fatty acid modification and coupling are able to improve the dispersion stability of the aqueous bronze powder, which mainly depends on the activity of a hydrophobic group and anion.The long chain hydrocarbyl of the dispersion stability is better than  short chain hydrocarbon group, an anionic high activity better than low activity.

(3)Copper powder floating depends on the used surface modifier and the arrangement of the copper powder in reagent outermost surface groups. It does this by changing copper powder density to affect wettability to affect the surface properties of copper 

powder, thereby affecting the buoyancy.Not the worst point wettability floating rate corresponding to the maximum value.

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(4)gloss water-based ink is impact by polishing of gold bronze powder,the modified reagent type and dispersion and floating capability of gold bronze powder in an aqueous liquid. When the agent is once adsorbed, the gloss depends on the rate of dispersion, while the secondary adsorption, mainly depending on the floating rate.

(5)In optimizing reagent, the amount of the antioxidant effect most on the gloss of the aqueous copper powder, followed by the type of antioxidant. Selecting 0.1% salicylic acid as an antioxidant, which is combined with 

surface modifiers, can effectively improve the water-based gloss bronze powder.

(6)Using 0.6% double hydrocarbon chain modifies copper stearate powder surface , enabling water-based gold ink up to 72.02,compared with unmodified gloss powder improves 91.34%, reaching the level of solvent-based gold ink.