tinting PETG with rit dye black, but ended up looking brownish?

[jenny]

Hi, im new here. I have read somewhere that black must be mix with certain color for it to turn black??? I did one pack of black rit dye and this is what it end up looking like not even close to black :confused

 

[GuntahKela]

What kind of fabric was it? Once, we tried to dye white denim into black, and we got brown/purple-ish, instead. The fabric wouldn't absorb the dye.

 

[PepMaster]

You either needed to use half the amount of hot water called for or double the dye. GuntahKela PETG is a Clear Plastic sheet that can be heated and dyed.

 

[division 6]

Sounds like a red based dye.
I have a piece that came out green because the black was green based.
Sometimes they are also blue based.

Black acrylic is also green based.

 

[Darth Lars]

I got a brown result too, dyeing PBT in liquid black RIT dye,
When looking into the issue, I came across people who claim that there is a difference between liquid and powder RIT dye. The powder dye is supposedly better.

Can I mix different RIT dyes? I do have some "Royal Blue" liquid and "Sunshine Orange" powder on hand ...

 

[trooper1m]

The reason for getting the brownish tint is beacause ,as some people have rightly said, because the ''black dye'' is made up of various colours to give something that's so dark in depth that it appears black. There is no such colour as black, black is a measurement of depth of shade and has no tone. For example if you took red, green, blue and yellow marker pens and scribbled one on top of the other you would get something that is probably so dark that it looks black when it's actually just red,blue,green and yellow mixed together. You would more than likely need to use 3 different coloured dye baths to get a decent black finish. 3 colours because anything less would be a secondary colour and you need to at least a tertiary colour to get the depth without having and one hue showing predominantly. Colours that are opposite each other on the colour wheel is the best idea i.e red and green are opposing colours and cancel each other out tonally but combined will give increased depth (darkness).......