I think any leave-in conditioner that as UV Protection will be good with respect to sunlight. IMO, the issue with leave-in conditioners is their tendency to leave residue/build-up on the hair. You'll want to rinse them out and use conditioner regularly. Some can really weigh down the hair or...
I would, however, agree that Injected Thin Skin is unparalleled in realism, as far as hair direction is concerned. Though the same issues are apparent with regards to plastic base potential for visibility.
IMO, knot sealers will interfere with the natural flow of the hair. Just like everything in the craft, it's a tradeoff between presentation and durability.
Coloring hair: Maintaining color fade
This section is not too much different than the sections above. However, in this case, you likely won't be bleaching the hair at all. If it is safe to assume your hair color originally was perfect, then it should be possible to restore it to that color...
Coloring hair: Iterating on your hair samples and how to find your perfect bio-hair match
Each time you try a color formula, make sure you write it down along with a label code. I used labels such as "C01" through "C07" for my coloring attempts with a 36 minute bleach, and "D01" through "D05"...
Coloring hair: Planning your color alteration
Coloring hair will consist of either one or two steps. If you are only trying to tone/correct fading from an existing colored hair, you will need only the dyeing step. If you are trying to color hair that is darker than your desired match, you need...
Coloring hair: Preparing hair samples
Finding the perfect formula will no doubt take some trial and error. You'll want to make some hair samples for color tests. If you are starting with purchased hair from a weft or a loose bundle, this will be plentiful. If you are working only from a factory...
Coloring hair: Products and equipment
Now we'll use a lot of the science explained up above.
Selecting the right tools
The first thing you need to do is buy coloring tools. You will need a mixing bowl, a good brush, aluminum foil, a color tube key, and a 0.1g scale.
Color tube key...
Color Terminology
Hair color is described as tones and levels.
Tone
The tone is essentially the ratio of blue, red, and yellow. If your hair has more blue molecules than it does red and yellow, you have an "Ash" or a "cool" toned hair. If your hair has some reddish to it, then you have...
Color Theory
Let's now take a step back and understand how colors combine to make other colors. We all remember the color wheel from high school art class? Great, throw it out the window. The only thing you need to take from that is that all three primary colors make brown.
If you have red...
Why bleaching the hair always results in a red or yellow result
Because Pheomelanins are much harder to oxidize than Eumelanins, the bleach will remove blue long before it removes red and yellow.
I made a chart showing how bleaching a Level 1 super dark brown / black hair will result at every...
The science behind natural hair coloring
Now we're getting into the color science!
Natural hair pigment is made of melanins, like your skin color. However, these are called "Eumelanins" and "Pheomelanins."
Eumelanins contain all the cool colors. For simplicity, let's say that the "blue" is...
The composition of the hair strand
The human hair has three layers.
Cuticle
The outer layer is called the Cuticle. This layer is very thin, and acts like a shell of scales protecting the interior from moisture loss. They can make the hair look smoother and shinier.
The cuticle can open up...