Kodalith Type Developer Formula

[Mark Layne]

So can anyone tell me what the difference between Kodalith and Kodalith Fine Line is. I have lots of the latter but I do not seem able to get it to produce any pink colour on lith prints the way my old Dupont Cronalith will.
I suspect it is formulated to have less agressive infectious development.
So what can I add to bring out some colour. A little Kbr maybe?
Mark

 

[dancqu]

Ansco 81 isn't bad. It doesn't have the rapid 'infectious' action
of Kodalith AB, but it doesn't require any formeldehyde or lye,
either. It keeps for months.

Per liter:

35. gm Hydroquinone
55. gm S. Sulfite
80. gm S. Carbonate
5.5 gm Citric Acid
10. gm P. Bromide

Use full strength, developing time not longer than 3 minutes.

Save for the citric acid and bromide the formula is similar to
that of Wall's. Wall's cuts right to the lith phenomenon itself
with no extras. Both Ansco 81 and Wall's use a carbonate
to activate the hydroquinone.

With low sulfite levels infectious development will occur as
the byproducts of development produce even more energetic
development and exponetionally more of the byproducts.

A carbonate provides the high ph needed for reasonable
development times. I've processed with a 50-50 blend of
carbonate and bicarbonate with increased time. The
generation of very high ph byproducts through the
interaction of additional chemistries is beyond
the needs of a lith developer.

Formaldehyde is included as a slow release agent which
maintains the necessary low sulfite level while at the
same time increases the longevity of working
strength lith chemistry. Dan

 

[Ray Rogers]

10% of saturated formalin (40% vol.) = 4% (vol.) formaldehyde

4% formaldehyde [is] not equal to 10% formalin since formlain is formaldehyde.

Ron,
I think Ted is defining 10% formalin as a 1:9 dilution of 100% Formalin* with HOH;

*
100% Formalin being the saturated aqueous soluton of the gas
which is 37% by weight formaldehyde... but 40% by volume.

10% of 40% gives a 4% Formaldehyde gas solution.
----------------------------------------------------
BTW, anyone see "Yes Man" ? It has a very tiny, yet nice, social commentary about Photography and Photographers... humor and a nice message as well!

Ray

 

[Ray Rogers]

Save for the citric acid and bromide the formula is similar to that of Wall's.

Formaldehyde is included as a slow release agent which
maintains the necessary low sulfite level while at the
same time increases the longevity of working
strength lith chemistry. Dan

------------------------------------
I must have missed something!
Walls What?

In what is Formaldehyde included?
Wall's, Ansco 81 or D-85
?

 

[Photo Engineer]

Ron,
I think Ted is defining 10% formalin as a 1:9 dilution of 100% Formalin* with HOH;

*
100% Formalin being the saturated aqueous soluton of the gas
which is 37% by weight formaldehyde... but 40% by volume.

10% of 40% gives a 4% Formaldehyde gas solution.
----------------------------------------------------
BTW, anyone see "Yes Man" ? It has a very tiny, yet nice, social commentary about Photography and Photographers... humor and a nice message as well!

Ray

Ray;

That very well may be so but it should be specific as the context implies that formalin and formaldehyde are two different things when they are not.

The statement, as posted above, is incorrect, regardless of intent by the poster or the originator.

PE

 

[Ray Rogers]

the context implies that formalin and formaldehyde are two different things when they are not.

PE

I agree with you.

Of course, they are different; one is a gas, the other is it's solution.
Formaldehyde contains no water.

Ted actually points out terms that have been deprecated.
(but makes an error at one point describing a 10% solution)

Anyway, we often say formaldehyde when we should say
"a formaldehyde solution" (or "formalin").

 

[Cor]

Hi Bill and Nicholas,

Thanks for the formulas. I have everything but the paraformaldehyde so will probably go with Nicholas's formula. What does that do?

Sandy

I might be mistaken, Tim Rudmen's book on Lith printing is at home, but I believe that other function of the formalin is to "bond" the sulphite ions (I believe PE referred to it, if I understood him correctly). To be able to do Lith printing (on certain B&W papers that is) infectious development should take place. For this process as little or no Sulphite should be freely present..

Best,

Cor

 

[dancqu]

I might be mistaken, Tim Rudmen's book on Lith printing
is at home, but I believe that other function of the formalin
is to "bond" the sulphite ions (I believe PE referred to it, if
I understood him correctly).

To be able to do Lith printing (on certain B&W papers that is)
infectious development should take place. For this process as
little or no Sulphite should be freely present.. Best, Cor

My post 27 mentions the connection twixt formaldehyde
and sulfite. There is a bonding. Sulfite levels must be kept
low so that infectious development may take place. At the
same time developer longevity requires a preservative.
So, the formaldehyde. Apparently sulfite combined
will not retard infectious development while that
free in solution will retard development.

Likely sulfite levels should not exceed bonding capacity.
Formulators may wish to keep that in mind. Of course
no formaldehyde is necessary where short tank or
tray life is expected. In the little lith work I've
done none was used.

That I believe is the only reason for the formaldehyde;
maintaining the presence of a preservative, sulfite, in
some quantity above a lith developer's in solution
allowable. Dan

 

[dancqu]

I must have missed something!
Walls What?

In what is Formaldehyde included?
Wall's, Ansco 81 or D-85 ?

Wall's Normal Hydroquinone is a most basic lith
developer; hydroquinone, sulfite, carbonate. Like
the other two, 81 and 85, it is a film developer.
Any of the three will do for paper when very
dilute. IIRC only 85 uses formaldehyde. Dan

 

[Ian Grant]

Formaldehyde is in Reprolith - Agfa Ansco 79 & 79b, Kodak D85 & D85B, Dupont LD1, Dupont 7D, Ilford Formalith and other more obscure lith developrers, as well as a whole host of commercial lith developers from a variety of companies.

It's fair to say that virtually every manufacturer supplying the graphics trade produced a formaldehyde based Lith developer because these developers have very significant advantages over other high contrast developers for many types of graphics work.

Kodak now use Sodium Formaldehyde Bisulphite in most of the various types of Kodalith, these are all derived from D85.

Ian

 

[spongeboy]

Kodalith halftone developing: any update?

Sandy,
I just came across this discussion on your Kodalith halftone development options....
have you, or others any updates for us? Muchly appreciated....