IMPROVEMENTS. TO DRINGING ARDMAIN TRETILE FARRICS AND YARNA
Year: 1867

page_text: LETTERS PATENT to John Lightfoot, of Lower House, near Burnley, in
i
the County of Lancaster, Chemist, for the Invention of "IMPROVEMENTS.
TO DRINGING ARDMAIN TRETILE FARRICS AND YARNA."
Sealed the 21st April 1868, and dated the 26th December 1867.
PROVISIONAL SPECIFICATION left by the said John Lightfoot at the
Office of the Commissioners of Patents, with his Petition, on the
26th December 1867.
I, JOHN LIGHTFOOT, of Lower House, near Burnley, in the County of
Lancaster, Chemist, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN PRINTING CERTAIN TEXTILE FABRICS AND YARNS," to be as.
follows:-
My improvements consist in applying to textile fabrics and yarns, and more
particularly those made of cotton or linen, particular preparations of indigo,
either simply thickened when blue colours only are required or mixed with a
salt or salts of lead when shades of green are required. With the preparations
thus made the goods may be either printed or padded, or when the goods are
intended to be dyed the usual mordants are simultaneously applied, but in
...

page_text: either case I then after drying pass the goods into a solution of silicated alkali,
or carbonated alkali, or mixtures of these, and wash in water, proceeding after-
wards in the cases where mordants for dyeing are used along with the indigo
preparations to dye in the dye stuffs proper for the colours required to be pro-
duced. I make the preparation of indigo by any of the following methods:-
I take of dry indigo in a ground or powdered state, or in the state usually
called in the trade "indigo pulp," one and a quarter pounds; of muriate of
tin in crystals, one and a quarter pounds; and one gallon of a solution of
caustic potash or soda; I put in a pan and raise to boil. I then add one
gallon of boiling water. I prefer now to allow the mixture to become
perfectly cold and pour it into three gallons of cold water, in which I prefer to
dissolve previously eight ounces of sugar or one pound of treacle, though this
addition is not essential. I add to this solution three pints of muriatic acid
or one pint of sulphuric acid of commerce, previously diluted with one pint
of water or three quarts of ascetic acid; I can also precipitate with a mixture
of muriate of tin liquor and any of the acids named, taking less of them in
proportion to the quantity of muriate of tin used, the maximum quantity of
which should not exceed one quarter of a pint. I then filter the precipitate
to one gallon of pulp, which I call "indigo precipitate." Instead of the
muriate of tin crystals in the above preparations I can use protoxide of tin by
precipitating a solution of protosalt of tin with an alkali or alkaline earth,
washing and filtering to a pulp or drying to powder, using such a proportion
as shall contain an amount of tin equal to that in the muriate of tin crystals;
or I boil the mixture of indigo and caustic alkali with metallic tin in powder
or granulated, the quantity being such that when the boiling is finished
undissolved metallic tin remains; or in lieu of a protosalt of tin or the
protoxide I can use the sulpbo-stannate of sodium or potassium prepared by
dissolving the bi-sulphuret of tin in caustic soda or potash, or sulphuret of
sodium or potassium. In all these cases I precipitate with an acid or acid
mixture, as above described.
To make a blue colour for printing or padding I take one gallon of the
indigo precipitate and three to four pounds of gum senegal or other suitable
thickening matter and stir till all the gum is dissolved.
To make a green colour I take one gallon of indigo precipitate, three to four
pounds of gum as before, and add a sufficient quantity of a salt of lead. 'Other
shades when meant for dyeing can be produced by various mixtures of the blue
and green colours with the mordants usually used in dyeing. I pass the goods 'so
printed or padded into a solution of carbonated alkali or into a solution of silicated
alkali, which latter may contain a little chalk, and then be rinced in water. If

page_text: only blue has been printed or padded the goods may now be washed and dried.
If green be padded or printed alone or along with blue I next pass the goods
into a weak solution of bi-chromate of potash in water, then rince in water
and wash and dry. Where blue and green or either is printed along with:
ordinary mordants I take the goods after raising in bichromate of potash, and
after washing give the process usually called in the trade "after dunging" or
"second dunging;" then wash and proceed to dye with the dye stuff proper
for the shades required, such as madder, garancine, extract of madder,.
cochineal, or other dye stuffs. The ordinary methods of clearing the white
grounds inay be followed.
I wish it to be distinctly understood that the ingredients and proportions
above referred to have been found by experiments to give good results, but,
I do not limit myself to the details given, as other proportions and other.
ingredients possessing similar properties may be found by further experiments.
to answer the purposes described.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Lightfoot in the Great Seal Patent Office on the
25th June 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
LIGHTFOOT, of Lower House, near Burnley, in the County of Lancaster,
Chemist, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Iler Letters
Patent, bearing date the Twenty-sixth day of December, in the year of our
Lord One thousand eight hundred and sixty-seven, in the thirty-first year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said John Lightfoot, Her special license that I, the said John
Lightfoot, my executors, administrators, and assigns, or such others as I, the
said John Lightfoot, my executors, administrators, and assgns, should at any
time agree with, and no. others, from time to time and at all times. thereafter
during the term therein expressed, should and lawfully might make, use,
exercise, and vend, within the United Kingdom of Great Britain and
Ireland, the Channel Islands, and Isle of Man, an Invention for "IMPROVE
MENTS IN PRINTING CERTAIN TEXTILE FABRICS AND YARNS," upon the condition
(amongst others) that I, the said John Lightfoot, my executors or adminis
trators, by an instrument in writing under my, or their; or one of their hands

page_text: and seals, should particularly describe and ascertain the nature of the said
Invention, and in what manner the same was to be performed, and cause
the same to be filed in the Great Seal Patent Office within six calendar
months next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said John Lightfoot, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement (that is to say):-
My Invention consists in applying in the manner herein-äfter described to
textile fabrics or yarns, and more particularly those made from cotton or
linen, certain indigo preparations simultaneously with the usual mordants for
dyeing, the indigo preparations undergoing the usual operations of dyeing
and clearing along with the mordants, and the result being that blues, greens,
and other shades are produced along with the colors obtained by dyeing
mordants with dye stuffs. The use of indigotine, combined or mixed with an
oxide or salt of tin, for producing blue figures upon cotton or linen fabrics,
and subsequently raising these colours in an alkaline bath, is well known to
calico printers under the name of fast blue; or when mixed with a salt of
lead under the name of fast green. When applied in madder or. garancine
styles these colours have been usually blocked into spaces left vacant for
them after the pieces have been printed, dyed, cleared and dryed. From
time to time attempts have been made to print simultaneously with the
madder and garancine mordants, preparations of indigo, and, in some cases,
those named above as fast blue and fast green, so as to save the expense of
blocking in these colours after dyeing, but either from the blues and greens
so produced having been dull and wanting in vivacity, or from the mordants
having been attacked by the alkaline bath used to fix the indigo colours, and
the dyed colours thus coming from the bath poor and bare, or from special
apparatus having been necessary to print the indigo colours, these attempts
have never met with success. The discovery therefore of an efficient process
which will enable the simultaneous printing of blue and green with mordants
intended for dyeing to be successfully carried into practice was and remained
a desideratum up to the date of this Patent. I have succeeded in discovering
that the difficulties which have prevented success hitherto may be obviated,
and by using the indigo preparations as herein described, and by employing
for fixing indigo blue and green in juxtaposition with ordinary madder
inordants the materials herein-after' mentioned, which materials have not been
so used before. My process enables me to produce fine blues and greens
which are printed at tlie same time as the ordinary mordants for reds, purples

page_text: chocolates, and black, and undergo with them the operations required to dye
and clear these colors. I make a preparation of indigo, fulfilling the
required conditions by employing much less tin, whether as oxide or in the
state of salt, in the process of dissolving the indigo than has hitherto been
used, and also by dispensing with the addition of a salt of tin to the pre-
cipitated indigotine, whether this has been made by the aid of oxide or salt.
of tin, or, as is sometimes the case, by the aid of metallic tin, because I.
have ascertained that if the tin is in excess of a certain proportion to the
indigo oxide of tin is left in the fibre during the process of fixing the indigo
colours and the mordants, and thus acting itself as a mordant becomes dyed
by the dye stuff, producing with the indigo compound colours which in the
case of blue are more or less purple and dull, and in the case of green are
more or less a sombre olive. This use of tin in excess has been one of the
causes of the failures to which I have before alluded.
:
I prepare a paste or pulp of indigotine and tin suitable for my improved
process by any of the following methods:-I take of dry indigo in a ground
or powdered state one and a quarter pounds, or when indigo pulp is used,
using such a quantity as to be equal to one and a quarter pounds of dry
indigo, of protochloride of tin in crystals one and a quarter pounds, and 'of
caustic soda at thirty degrees on Twaddell's hydrometer, or of caustic potash
at frty degrees on Twaddell's hydrometer, one gallon. I put these materials
in a pan and raise to boil in half an hour, and then add one gallon of boiling
water. I prefer now to allow the mixture to become perfectly cold, and
pour it into three gallons of cold water, in which I prefer to dissolve eight
ounces of sugar or one pound of treacle (though this addition is not essential) I
add to this solution two and a half pints of muriatic acid at thirty-two degrees
of Twaddell's hydrometer, or one pint of sulphuric acid of commerce, pre-
viously diluted with one pint of water, and allowed to stand till clear, or
three quarts of acetic acid at eight degrees of Twaddell's hydrometer. The
indigotine may also be precipitated by a mixture of protochloride of tin
solution at one hundred and twenty degrees of 'Twaddell's hydrometer, with
any of the acids named, using one quarter of a pint of tin solution and only
half the quantities of the acids given above, this quantity of tin solution being
the maximum that I can use when precipitating the indigotine for producing
a fine blue and green. Of all these precipitants I prefer to use "acetic acid
alone." Instead of using protochloride of tin crystals in making the indigo
solution, protoxide of tin made by precipitating a solution of protosalt of
tin with an alkali may be used, the precipitate being washed with water and

page_text: filtered to a thick paste, or anhydrous protoxide of tin made in any convenient,
way may be employed, in all cases taking such a proportion of oxide as shall.
contain an amount of tin about equal to but not greater than that in one and
a quarter pounds of crystallized protochloride. In some cases the mixture.
of one and a quarter pounds of indigo and one gallon of alkali may be boiled
with metallic tin in powder or granulated, the quantity of the latter being,
such that when the boiling is finished and the indigo all dissolved there shall,
be metallic tin. undissolved. In all these cases I precipitate the indigotine;
as previously described. I filter the indigotine precipitate through a deep.
conical filter so as to leave as small a surface exposed to the air as possible;,
when filtered the pulp should measure one gallon or thereabouts.
To make a blue color for printing I take four gallons of indigotine pre-,
cipitate and fourteen pounds of gum senegal in powder, stirring until dissolved.
(other suitable thickening substances may be used), after straining the colour
is ready for printing.
To make a green colour I take four and a quarter gallons of indigotine
pulp and eighteen pounds of gum senegal in powder, stir till dissolved, and
add eleven pounds of nitrate of lead in powder, and eleven pounds of white
acetate of lead in powder, stir till dissolved and strain.
Compound colours may be made by mixing the blue and green colours
with each other, or with the ordinary mordants for dyeing. With the
blue and green above described and the ordinary ferruginous and aluminous
mordants I print cotton and linen fabrics, and after cooling hang the pieces
in a room known to printers as an ageing room for one night, I then cause
them to undergo what is known as the fixing operation by passing them
into a solution of silicate of soda or silicate of potash at eight degrees of
Twaddell's bydrometer, or into a solution of carbonate of potash at twelve
degrees of Twaddell's hydrometer, to which about one ounce of chalk in
powder per gallon may be added, or into a mixture of silicate of soda or
silicate of potash at eight degrees of Twaddell's hydrometer with carbonate
of potash at twelve degrees of Twaddell's hydrometer. I heat the bath
to ninety degrees Fahrenheit or thereabouts in a cistern fitted with rollers,
at the top and bottom, and the passage of the pieces may be at the rate of
twenty-five yards per minute. On leaving this the pieces must be quickly
winced in a pit of cold water fitted with a reel about four feet above the
surface of the water. By this wincing the indigotine attached to the fibre be-
comes again indigo blue. If green has been printed I next pass the pieces into
a solution of bi-chromate of potash containing one ounce of bi-chromate of

page_text: the goods are then washed.
potash per gallon of water at one hundred degrees Fahrenheit for five minutes,
If only blue has been printed along with the
mordants this process may be omitted. I next subject the pieces to the
operation known to calico printers as "second dunging," and which consists
in making the pieces circulate in a beck containing cowdung and water at a
temperature of about one hundred and sixty degrees Fahrenheit for from
fifteen to twenty minutes. They are then washed with water and dyed with
madder, munjeet, flower of madder, garancine, extract of madder, cochineal,
mixtures of garancine with sumac and bark, or with either of them, after
which the ordinary operations of clearing the white grounds may be performed,
preference being given to the chloride of lime clearing usually adopted with
garancine colours.
Now, although the proportions above given have been ascertained by me to
be in practice the best for the purposes desired to be effected, it is obvious
that they may be slightly varied without departing from the nature of my
Invention, which for its successful operation depends materially upon keeping
the ratio of tin to indigo much lower when making indigotine colours intended
for printing along with mordants to be dyed with the dye stuffs named or similar
ones than in the fast blues and greens hitherto in use, and to avoid the use of
salt of tin in the printing colours made therefrom; and here let it be observed
that I make no claim to making a solution of indiget'ne in caustic alkali by
means of protochloride of tin or protoxide of tin; nor do I claim its use
otherwise than in my improved process as described and substantially in the
proportions given above; and I make no claim to dissolving indigo in caustic
alkali by the aid of metallic tin, such solution being well known; but I claim
the improved process herein described, the making of blue and green colors
from the above-mentioned solutions or their equivalents in such a manner
that the indigotine remains combined or mixed with such a small proportion
of tin oxide that none or nearly none is fixed in the fibre by the subsequent
processes, and consequently that there is little or no tin lake formed with the
dye stuff to spoil the purity of the blue and green. I am aware that carbonate
of potash may have been used to fix fast blue and green made with indigo
and tin, but it was not known that it could with advantage be used as described
by me to fix aluminous and ferruginous mordants at the same time; and I
therefore claim the use of carbonate of potash for fixing simultaneously
indigotine colours and mordants intended for dyeing as herein described. I
am also aware that "alkaline silicates" have been used to fix mordants
intended for dyeing, and that they have in some cases been proposed to be
used cool and stronger than in the usual way of using them as "cowdung

page_text: substitutes," but it was not known that they could be used to effect the simul
taneous fixing of ordinary mordants and indigotine colours as described herein,
and I therefore claim their use for this purpose.
In witness whereof, I, the said John Lightfoot, have hereunto set my
hand and seal, this Twentieth day of June, One thousand eight
hundred and sixty-eight.
JOHN LIGHTFOOT. (L.s.)