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""...the bog-common blue pigment, to dye fabric to the darkest possible midnight tint. Then a second dye, typically a red (madder) or yellow (weld), would be ad

""...the bog-common blue pigment, to dye fabric to the darkest possible midnight tint. Then a second dye, typically a red (madder) or yellow (weld), would be added over the top to eliminate the blue tinge."" I've occasionally wondered about dyes, their stability, and how they were fixed pre modern chemistry (before early-to-mid 19th C., Perkins et al), for me the practice of dyeing and its fixing process is a bit of a black art. Mind you, my experience at dyeing stuff is rather limited and I haven't attempted it in while. I mostly come at it from the other end when trying to get clothes clean and dyes either run or change color in the process. For instance, I had several pairs of almost identical navy blue work shorts made by two different manufacturers (the colors were essentially identical from each manufacturer). On one occasion I put two pairs of rather dirty shorts into a prewash stain remover to soak overnight, each pair was from a different manufacturer. The stain remover did a good job on both at removing stains but it turned one pair to a bright lairy magenta color whilst the color of the other remained completely unaltered. The magenta pair was so bright that it was rendered useless (I could do without the catcalls). A second similar incident occurred with a high-vis safety shirt colored florescent yellow and black. The yellow remained unaffected but the black turned a mottled darkish magenta color (it was still wearable however). Also, I've noticed other black clothing, T-shirts etc., will often tend towards a blackish magenta on harsh washing. It seems thus that we still have a problem dyeing deep black—or at least keeping it that color without it getting dull, dowdy and slightly shifting in hue. Although I have a little knowledge of dyes and pigments from chemistry, indigo, azo, mordant red, etc., I've little idea what dyes are used for black other than it seems to be at least a two-color process. Perhaps things haven't changed as much as I'd thought (right, we know indigo has been with us for millennia but I'm a bit surprised we've still a problem with black). Is anyone up-to-date about dying stuff black? Edit: BTW, I've noticed that when trying to remove black ballpoint pen stains from shirt pockets with solvents such as ethanol that the color upon dilution is often not black but rather dirty shades of a magenta/bluish color. Seems we've a similar problem here.

sorokod 3y ago
Some paractioners of Japanese martial arts wear a hakama, a sort Japanese trousers (not a great description this, have a look online). The tradionalists go for a proper indigo hakama which absolutley "bleeds" it's colour to the annoyance of practice partners. Check out the care instructions from one traditional hakama manufacturer https://iwataco.com/about_hakama#care https://iwataco.com/about_hakama#care
- hilbert42 3y ago
  Thanks for that link. Having seen Japanese martial arts I was vaguely aware of what practitioners wore although I had no idea they were called 'hakama'. In fact, until I saw the link (having not thought about it), I'd assumed they were 'jet-black'—if I may use that term here. Indigo is notorious for fading—its deemed virtue—but what I'm surprised about is how deep a blue it is here (its deeper than the bluest of unwashed denim). I wonder if any other dark dyes or pigments are added to increase the blackness. I'm notorious for getting very grubby when stripping machines down for maintenance, etc. so I'm familiar with getting 'black' oil and grease stains out of clothes, it's very difficult and in some cases impossible. The black in oils and grease comes primarily from metal oxides and sometimes graphite, these aren't dyes as such but are in effect pigments. Some oxides/pigments can be very black (almost neutral) and some of their fine particulates lodge mechanically (and often tenaciously) in the fibers and can stay there permanently (a little like a tattoo in human skin). That said, only a 'small' percentage of a pigment will remain fixed to the fibers but what stays there does so permanently (like carbon black in printer's ink a mechanical mechanism (the binder) is need to hold it there). I'm now curious, perhaps some of these very black materials are a combination of a black substrate pigment buffered with either azo blues and or indigo. Just a thought.
  - sorokod 3y ago
    Indigo is perceived more traditional then black, some places allow indigo, some demand. By the way, indigo bleeding is not limited to washing, the colour actually rubs off during training. It is turned around and seen a virtue since your garment becomes uniquely yours as it fades.
    - hilbert42 3y ago
      Right, somewhere in my past I got the impression that the original reason (before it became fashionable) for why manufacturers started pre-washing jeans was to stop the problem of indigo rubbing off onto furniture, chair seats etc. I recall when I was a kid before the pre-washing era started that the labels on some jeans advised that (a) jeans are to be washed before wearing and (b) they could shrink up to 5% after washing (i.e. buy a sloppy fit). My mother insisted that jeans be washed first as she warned that I'd be in dead trouble if I got blue patches on her light beige lounge suite. This was a bit of a ritual, blue jeans first had to be washed and then only worn outside until the second wash, brown and black jeans only had to be washed once! Re indigo fading, even now jeans manufacturers advise not to wash denim until really necessary so as to develop one's own characteristic fade marks. My point about very black materials and pigments was broader than just the hakama, materials such as black felt hats, women's dead-black shawls, and men's monkey suits, black parchment paper, etc. These are as black as the current technology permits—whatever it is.

sorokod 3y ago

Some paractioners of Japanese martial arts wear a hakama, a sort Japanese trousers (not a great description this, have a look online). The tradionalists go for a proper indigo hakama which absolutley "bleeds" it's colour to the annoyance of practice partners. Check out the care instructions from one traditional hakama manufacturer https://iwataco.com/about_hakama#care https://iwataco.com/about_hakama#care

hilbert42 3y ago
Thanks for that link. Having seen Japanese martial arts I was vaguely aware of what practitioners wore although I had no idea they were called 'hakama'. In fact, until I saw the link (having not thought about it), I'd assumed they were 'jet-black'—if I may use that term here. Indigo is notorious for fading—its deemed virtue—but what I'm surprised about is how deep a blue it is here (its deeper than the bluest of unwashed denim). I wonder if any other dark dyes or pigments are added to increase the blackness. I'm notorious for getting very grubby when stripping machines down for maintenance, etc. so I'm familiar with getting 'black' oil and grease stains out of clothes, it's very difficult and in some cases impossible. The black in oils and grease comes primarily from metal oxides and sometimes graphite, these aren't dyes as such but are in effect pigments. Some oxides/pigments can be very black (almost neutral) and some of their fine particulates lodge mechanically (and often tenaciously) in the fibers and can stay there permanently (a little like a tattoo in human skin). That said, only a 'small' percentage of a pigment will remain fixed to the fibers but what stays there does so permanently (like carbon black in printer's ink a mechanical mechanism (the binder) is need to hold it there). I'm now curious, perhaps some of these very black materials are a combination of a black substrate pigment buffered with either azo blues and or indigo. Just a thought.
- sorokod 3y ago
  Indigo is perceived more traditional then black, some places allow indigo, some demand. By the way, indigo bleeding is not limited to washing, the colour actually rubs off during training. It is turned around and seen a virtue since your garment becomes uniquely yours as it fades.
  - hilbert42 3y ago
    Right, somewhere in my past I got the impression that the original reason (before it became fashionable) for why manufacturers started pre-washing jeans was to stop the problem of indigo rubbing off onto furniture, chair seats etc. I recall when I was a kid before the pre-washing era started that the labels on some jeans advised that (a) jeans are to be washed before wearing and (b) they could shrink up to 5% after washing (i.e. buy a sloppy fit). My mother insisted that jeans be washed first as she warned that I'd be in dead trouble if I got blue patches on her light beige lounge suite. This was a bit of a ritual, blue jeans first had to be washed and then only worn outside until the second wash, brown and black jeans only had to be washed once! Re indigo fading, even now jeans manufacturers advise not to wash denim until really necessary so as to develop one's own characteristic fade marks. My point about very black materials and pigments was broader than just the hakama, materials such as black felt hats, women's dead-black shawls, and men's monkey suits, black parchment paper, etc. These are as black as the current technology permits—whatever it is.