Naked Science Forum

General Science => General Science => Topic started by: jai on 06/07/2004 12:10:42

Title: does partical size have anything to do with colour
Post by: jai on 06/07/2004 12:10:42
am a tattooist and i understand that ink stays in the skin because the partical size of the ink is too large to move through the cell membrane, thus trapping the ink in the dermis. however also heard that one of the contributing factors to colour is the size and shape of the partical. lighter colours have been more difficult to produce as inks, is this the reason? and is this in any way true? what does size have to do with colour?
Title: Re: does partical size have anything to do with colour
Post by: Ylide on 07/07/2004 23:03:32
The short easy answer is yes, the size and shape of the molecule are what give it it's color.  

More specifically, the type, number, and character of the chemical bonds that make up the molecule affect which wavelengths of light are absorbed.  Most dyes are aromatic (in the organic chemistry sense of containing a conjugated double bond ring structure) and have amino groups and non-ring double bonds.  The interactions of these are complex and hard to understand without going into quantum mechanics.  Essentially, it comes down to certain bond configurations absorbing certain wavelengths of electromagnetic energy.

Incidentally, sunscreen works on the same principle, it's just a material that absorbs electromagnetic radiation that falls into the UV range spectrum instead of the visible light range of the spectrum.

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Title: Re: does partical size have anything to do with colour
Post by: jai on 08/07/2004 23:27:25
cool, does this mean that to get some colour pigments to stay in the skin they would have to bond them to ?? each other?? other things?.  and would this therefore have something to do with why these pigments break down in the skin faster than others. i.e. red pigments and yellows break down much fast than other colours. i understand that this is heavily contributed to by exposure to sunlight but the same sun light does not break down the other colours as quickly. alternately, does this have something to do with the fact that the red and yellow are at the shorter (?) end of the spectrum wavelength and so . . . .  ? sorry lost the thought. but does it?
Title: Re: does partical size have anything to do with colour
Post by: Ylide on 11/07/2004 18:30:27
I'm not sure of the physiology of tattoo dyes.  I have a few myself, but I don't know if it's held into place because it actually stains cells or if it lies in between cells.

As far as pigments breaking down, in tattoos that's caused by exposure to UV radiation in sunlight.  The dyes also absorb energy in the UV spectrum.  The reds and yellows either absord more readily in that spectrum (less likely) or they lose their color due to broken bonds more easily. (more liklely)  Again, just speculating, I can't say for sure without knowing exactly what dyes are used and their molecular structure.



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Title: Re: does partical size have anything to do with colour
Post by: jai on 15/07/2004 10:34:06
i dont think that the ink dyes the cells because then it would surely dissapear slowly as the cells replace themselves (you know, the seven year thing, and how true is that anyway?). or would the dye just be absorbed into the next cell????

yes, but.........
Title: Re: does partical size have anything to do with colour
Post by: qazibasit on 16/07/2004 16:42:00
well what i know is that if you want to penetrate the partical through the dermis then you should use hyaluronic acid it would help you penetrate the substance

ya its also true big inorganic particals cant penetrate through the membrane coz the channels are very small and it is the only way you can send any inorganic matter through the cell.
Title: Re: does partical size have anything to do with colour
Post by: Broca on 27/07/2004 02:48:31
Sometimes the ink can calsify a bit. It is not any big deal unless the tat is on your breast and you are a woman who goes for a mammogram. There are some breast cancers that are found due to small calcifications. If you have a tat on your breast make sure that the technologist either writes on the requisition form that you have one and where it is or better yet, there are small "beebes" that can be placed around the tat to outline it on the film. Many woman have been called back for biopsys that were not needed because of this.
Title: Re: does partical size have anything to do with colour
Post by: jai on 27/07/2004 11:11:34
thanks! [:)], i didnt know this! i have a lot of tattoos, some of which are on my breasts and as yet have not had to have a mammogram (touch wood). do you know and could you tell me how calicification happens? i have heard of it on bones that have been damaged but never on soft tissue and i am not really sure of the process. thanks

yes, but.........
Title: Re: does partical size have anything to do with colour
Post by: Broca on 27/07/2004 23:28:02
I am not the medical expert here...not by a long shot...but<laughing>  I know that sometimes when cysts rupture (yes, even in the breasts)there are calcifications formed and also, like I said, calcifications are indicitive of some cancers. I am certain someone will answer that for you.
For those of us who sport our tats other places than the breast, we still need to be careful during a mammo as far as NOT wearing deoderant. Some sprays have aluminum chlorhydrate which can also mimic calcifications. amazing isn't it?