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black photoresist masters - darkening

black photoresist masters - darkening

2005-07-25 by hjf2k2

Hi all, I'm still working on the serigraphy emulsion system. I think I
need to increase the exposure time to burn the emulsion a little
more. The problem is that I'm using transparencies with toner as
masters, and toner, even from a new cartridge, is not totally black.
So I went to the serigraphy shop and found a very interesting product:
toner darkener. It's actually called toner blackener in my language
(ennegrecedor de toner), but I found it as darkener on google.
It's a spray, cheap, about $7 for the local brand and $15 for an
european brand, which the guy told me is used to make masters for
offset prints. So I bought that one and sprayed it on a transparency.
the effect was INSTANT, it dried up in a few seconds and the toner is
now totally black, even under the sun!
So to all people using photo resist, this might be an interesting
option. Also to people who use toner transfer, maybe this will help
with thin lines? I didn't see if it leaves residue as the test
transparency I used had no transparent edges.

Re: [Homebrew_PCBs] black photoresist masters - darkening

2005-07-25 by Leon Heller

----- Original Message -----
From: "hjf2k2" <drgenio@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Monday, July 25, 2005 3:42 PM
Subject: [Homebrew_PCBs] black photoresist masters - darkening


> Hi all, I'm still working on the serigraphy emulsion system. I think I
> need to increase the exposure time to burn the emulsion a little
> more. The problem is that I'm using transparencies with toner as
> masters, and toner, even from a new cartridge, is not totally black.
> So I went to the serigraphy shop and found a very interesting product:
> toner darkener. It's actually called toner blackener in my language
> (ennegrecedor de toner), but I found it as darkener on google.
> It's a spray, cheap, about $7 for the local brand and $15 for an
> european brand, which the guy told me is used to make masters for
> offset prints. So I bought that one and sprayed it on a transparency.
> the effect was INSTANT, it dried up in a few seconds and the toner is
> now totally black, even under the sun!
> So to all people using photo resist, this might be an interesting
> option. Also to people who use toner transfer, maybe this will help
> with thin lines? I didn't see if it leaves residue as the test
> transparency I used had no transparent edges.

A similar technique I've heard of is to expose the transparency to some
solvent fumes.

Leon
--
Leon Heller, G1HSM
leon.heller@...
http://www.geocities.com/leon_heller



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Re: black photoresist masters - darkening

2005-07-25 by derekhawkins

> It's a spray, cheap, about $7 for the local brand

Was this "Laser Buddy" by any chance? While it darkens the print, I
find it "fogs" up the transparency somewhat. A respirator with organic
vapor cartridges is definitely recommended when spraying that stuff.
Got better results exposing the transparency to xylol vapor.

--- In Homebrew_PCBs@yahoogroups.com, "hjf2k2" <drgenio@h...> wrote:
> Hi all, I'm still working on the serigraphy emulsion system. I think I
> need to increase the exposure time to burn the emulsion a little
> more. The problem is that I'm using transparencies with toner as
> masters, and toner, even from a new cartridge, is not totally black.
> So I went to the serigraphy shop and found a very interesting product:
> toner darkener. It's actually called toner blackener in my language
> (ennegrecedor de toner), but I found it as darkener on google.
> It's a spray, cheap, about $7 for the local brand and $15 for an
> european brand, which the guy told me is used to make masters for
> offset prints. So I bought that one and sprayed it on a transparency.
> the effect was INSTANT, it dried up in a few seconds and the toner is
> now totally black, even under the sun!
> So to all people using photo resist, this might be an interesting
> option. Also to people who use toner transfer, maybe this will help
> with thin lines? I didn't see if it leaves residue as the test
> transparency I used had no transparent edges.

Re: black photoresist masters - darkening

2005-07-25 by hjf2k2

--- In Homebrew_PCBs@yahoogroups.com, "derekhawkins"
<derekhawkins@y...> wrote:
> > It's a spray, cheap, about $7 for the local brand
>
> Was this "Laser Buddy" by any chance? While it darkens the print, I
> find it "fogs" up the transparency somewhat. A respirator with organic
> vapor cartridges is definitely recommended when spraying that stuff.
> Got better results exposing the transparency to xylol vapor.
No, it was a Spanish brand, "abezeta". I wouldn't mind about the
fogging, as long as it lets the light through.

Re: black photoresist masters - darkening

2005-07-25 by derekhawkins

> I wouldn't mind about the
> fogging, as long as it lets the light through.

Vellum lets the light through too. In other words the fogging negates
the gains from using transparencies in the first place. You can get the
darkened print without the fogging using xylol vapor.


--- In Homebrew_PCBs@yahoogroups.com, "hjf2k2" <drgenio@h...> wrote:
> --- In Homebrew_PCBs@yahoogroups.com, "derekhawkins"
> <derekhawkins@y...> wrote:
> > > It's a spray, cheap, about $7 for the local brand
> >
> > Was this "Laser Buddy" by any chance? While it darkens the print, I
> > find it "fogs" up the transparency somewhat. A respirator with
organic
> > vapor cartridges is definitely recommended when spraying that
stuff.
> > Got better results exposing the transparency to xylol vapor.
> No, it was a Spanish brand, "abezeta". I wouldn't mind about the
> fogging, as long as it lets the light through.

Re: black photoresist masters - darkening

2005-07-25 by hjf2k2

I'll see if I can get some Xylol. What's the procedure for vaporizing
then?

> Vellum lets the light through too. In other words the fogging negates
> the gains from using transparencies in the first place. You can get the
> darkened print without the fogging using xylol vapor.

Re: black photoresist masters - darkening

2005-07-25 by derekhawkins

> I'll see if I can get some Xylol.

Homedepot sells it if you live in the US. If not, it is also called
xylene or dimethyl benzene.

> What's the procedure for vaporizing then?

Pour to about a 1/2" level in a container with mouth larger than the
area covered by the artwork. A plastic container (like a sandwich box)
can be used provided it's not also used for storing the xylol. Place
the transparency with artwork facing down over the mouth of the
container. Place a piece of thick cardboard with some form of weight
over the transparency. Check after 15 to 30 minutes. Careful, wait too
long and the toner may get so wet that it starts to run. Store the used
xylol in a sealed metal or glass container for reuse when done.



--- In Homebrew_PCBs@yahoogroups.com, "hjf2k2" <drgenio@h...> wrote:
> I'll see if I can get some Xylol. What's the procedure for vaporizing
> then?
>
> > Vellum lets the light through too. In other words the fogging
negates
> > the gains from using transparencies in the first place. You can get
the
> > darkened print without the fogging using xylol vapor.

Re: black photoresist masters - darkening

2005-07-25 by hjf2k2

> > I'll see if I can get some Xylol.
>
> Homedepot sells it if you live in the US. If not, it is also called
> xylene or dimethyl benzene.

No, I'm not in the US. If I get some of the product, I'll try that,
thanks for the info!

Re: [Homebrew_PCBs] Re: black photoresist masters - darkening

2005-07-25 by Leon Heller

----- Original Message -----
From: "derekhawkins" <derekhawkins@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Monday, July 25, 2005 8:18 PM
Subject: [Homebrew_PCBs] Re: black photoresist masters - darkening


>> I'll see if I can get some Xylol.
>
> Homedepot sells it if you live in the US. If not, it is also called
> xylene or dimethyl benzene.

Xylene is used in cellulose paint thinners.

Leon


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Re: [Homebrew_PCBs] Re: black photoresist masters - darkening

2005-07-25 by Leon Heller

----- Original Message -----
From: "derekhawkins" <derekhawkins@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Monday, July 25, 2005 8:56 PM
Subject: [Homebrew_PCBs] Re: black photoresist masters - darkening


>> Xylene is used in cellulose paint thinners.
>
> A common solvent used in many things...What's your point?

Just that paint thinners is widely available, xylene itself isn't easy to
find.

Leon



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Re: black photoresist masters - darkening

2005-07-25 by derekhawkins

> Just that paint thinners is widely available, xylene itself isn't
> easy to find.

It's very, very easy to get in the US, but I see your point. However,
depending on thinner, it may also have other ingredients that will
dissolve or degrade the transparency film rapidly. I wouldn't use
lacquer thinner for this purpose for example.


--- In Homebrew_PCBs@yahoogroups.com, "Leon Heller"
<leon.heller@b...> wrote:
> ----- Original Message -----
> From: "derekhawkins" <derekhawkins@y...>
> To: <Homebrew_PCBs@yahoogroups.com>
> Sent: Monday, July 25, 2005 8:56 PM
> Subject: [Homebrew_PCBs] Re: black photoresist masters - darkening
>
>
> >> Xylene is used in cellulose paint thinners.
> >
> > A common solvent used in many things...What's your point?
>
> Just that paint thinners is widely available, xylene itself isn't
easy to
> find.
>
> Leon
>
>
>
> --
> No virus found in this outgoing message.
> Checked by AVG Anti-Virus.
> Version: 7.0.338 / Virus Database: 267.9.4/57 - Release Date:
22/07/2005
>
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Re: [Homebrew_PCBs] Re: black photoresist masters - darkening

2005-07-26 by Leon Heller

----- Original Message -----
From: "Stefan Trethan" <stefan_trethan@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Monday, July 25, 2005 10:04 PM
Subject: Re: [Homebrew_PCBs] Re: black photoresist masters - darkening


> What is happening there, the fumes solving the toner making it flow?
> any ideas?

Yes, that's the way it works.

Leon


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Re: [Homebrew_PCBs] black photoresist masters - darkening

2005-07-26 by Zoran A. Scepanovic

Hello Leon,

Monday, July 25, 2005, 4:48:51 PM, you wrote:

LH> ----- Original Message -----
LH> From: "hjf2k2" <drgenio@...>
LH> To: <Homebrew_PCBs@yahoogroups.com>
LH> Sent: Monday, July 25, 2005 3:42 PM
LH> Subject: [Homebrew_PCBs] black photoresist masters - darkening


>> Hi all, I'm still working on the serigraphy emulsion system. I think I
>> need to increase the exposure time to burn the emulsion a little
>> more. The problem is that I'm using transparencies with toner as

epa<SNIP>

LH> A similar technique I've heard of is to expose the transparency to some
LH> solvent fumes.

LH> Leon
LH> --
LH> Leon Heller, G1HSM
LH> leon.heller@...
LH> http://www.geocities.com/leon_heller


You have good ears!

Tonner can be exposed to paint thinner vapours (something that Stefan do not like), to acetone vapours or even vapours of solvent for PVC based colors for serigraphy

--
Sincerely,
ø¤º°``````````````````````````````````````````````````````°º¤ø
ZAS ElMed | mailto:zasto@...
| http://www.zas-elmed.co.yu
| Tel/Fax: +381 11 344-0748
|
Zoran A. Scepanovic | Mob: +381 63 609-993
º¤ø,¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸,¸¸¸¸¸¸¸¸¸¸¸¸¸,ø¤º

*********
Pieces of seven! Pieces of seven! (Hrm, parroty error)
*********

[Non-text portions of this message have been removed]

Re: black photoresist masters - darkening

2005-07-26 by Phil

Hmmm, I wonder if post toner transfer, exposing the PCB to these
vapors would improve pinholing by causing the toner to flow a little.
Worth a try on my next board.

--- In Homebrew_PCBs@yahoogroups.com, "Zoran A. Scepanovic"
<zasto@y...> wrote:
> Hello Leon,
>
> Monday, July 25, 2005, 4:48:51 PM, you wrote:
>
> LH> ----- Original Message -----
> LH> From: "hjf2k2" <drgenio@h...>
> LH> To: <Homebrew_PCBs@yahoogroups.com>
> LH> Sent: Monday, July 25, 2005 3:42 PM
> LH> Subject: [Homebrew_PCBs] black photoresist masters - darkening
>
>
> >> Hi all, I'm still working on the serigraphy emulsion system. I
think I
> >> need to increase the exposure time to burn the emulsion a little
> >> more. The problem is that I'm using transparencies with toner as
>
> epa<SNIP>
>
> LH> A similar technique I've heard of is to expose the transparency
to some
> LH> solvent fumes.
>
> LH> Leon
> LH> --
> LH> Leon Heller, G1HSM
> LH> leon.heller@b...
> LH> http://www.geocities.com/leon_heller
>
>
> You have good ears!
>
> Tonner can be exposed to paint thinner vapours (something that
Stefan do not like), to acetone vapours or even vapours of solvent for
PVC based colors for serigraphy
>
> --
> Sincerely,
> ø¤º°``````````````````````````````````````````````````````°º¤ø
> ZAS ElMed | mailto:zasto@y...
> | http://www.zas-elmed.co.yu
> | Tel/Fax: +381 11 344-0748
> |
> Zoran A. Scepanovic | Mob: +381 63 609-993
> º¤ø,¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸¸,¸¸¸¸¸¸¸¸¸¸¸¸¸,ø¤º
>
> *********
> Pieces of seven! Pieces of seven! (Hrm, parroty error)
> *********
>
> [Non-text portions of this message have been removed]