Improvements in and connected with Pigments or Lakes suitable for the Manufacture of Wall-papers.
Year: 1895

page_text: Date of Application, 2nd Sept., 1895-Accepted, 25th Jan., 1896
COMPLETE SPECIFICATION.
Improvements in and connected with Pigments or Lakes suitable
for the Manufacture of Wall-papers.
I, CARL DENEYS, Merchant, of W. O. 12, Linie 37, St. Petersburg, in the
Russian Empire, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :—
The best pigments or lakes suitable for use in the manufacture of wall papers
are produced by precipitating soluble colouring matters upon a white material, and
especially by adding dissolved barium chloride to a solution of colouring matter
and sodium carbonate, the barium carbonate thus produced carrying the colouring
matter with it.
Pigment produced in this manner meets with much favour in the manufacture of
wall papers, and fancy papers, owing to its great spreading power and soft hue.
I have found, that a special technical effect may be produced, by substituting in
this manufacture a soluble strontium salt for the barium salt, the pigments thus
obtained having a peculiar fiery intensity and a beautiful hue.
'
A further advantage consists in the quantitative efficiency of these lakes; for
producing a given weight of a given shade, a considerably smaller quantity of
colouring matter may be employed, than in taking lakes made with barium chloride
as usual.
If Glauber's salt is employed instead of sodium carbonate, the pigments on the
strontium sulphate obtained in the process, are more intensely blue, just as the
pigments obtained on barium sulphate (blanc fixe) are bluer than those produced
on barium carbonate. I have tested the applicability of commercial coal tar
colours, and of various natural colouring matters, and have found, that most of
them can be used advantageously as strontium lakes.
Exceptionally beautiful and fiery shades ranging between orange or yellowish
and blueish-red can be obtained from the azo-colouring matters produced from.
diazo-benzene-chloride and its homologues and sulpho-acids with the naphtholes
and their sulpho-acids (orange II, crocein-orange, ponceau G, R, 2 R, 3R etc.),
from alpha and beta-diazonaphthyl-chloride and their sulpho-acids with the
naphtholes and their sulpho-acids blueish-red and brown shades (true-red A, B, C,
D, E, BT, etc., bordeaux S and R, amaranth, true-brown O and N etc.), from the
tetrazo colouring matter produced from tetrazodiphenyl-chloride and its homologues
with naphthylamine and naphthole-sulpho-acids and salicylic acid reddish brown,
blue and yellow shades (benzo-purpurin B, 4 B, 10 B, etc., chrysamine etc.), yellow
tints from tartrazine, and fine yellowish brown tints from the natural colouring
matter flavin.
It may be mentioned, moreover, that I have specially prepared for these
experiments various coal tar colours not obtainable in commerce, notably azo-dyes,
and have obtained useful results for instance from the colouring matter derived
from diazo benzene chloride and sodium sulphanilide (yellowish variety) and
sodium naphthionate.
It is advantageous to combine the manufacture of the colouring matter with the
production of the lake, by adding to a cold diazo-solution (kept at a low
temperature) the necessary quantity of strontium chloride, and to the alkaline
solution of the phenole or naphthole, or their carbon acids or amido-sulpho-acids,

page_text: the quantity of soda solution which is necessary for the formation of the azo
colouring matter and for the complete precipitation of the strontium.
The geranium, márroon, and similar lakes which find so much favour in the
manufacture of wall papers may be produced in very fiery hues, from pure lakes of
bordeaux S or R, or (and preferably) by subsequently dyeing the fiery red lakes
obtained from ponceau, with other coal tar colours, such as fuchsin, violet, to which
special tints may be imparted by the addition of tannin. Basic colouring matters
may be used by treating the previously formed strontium carbonate with the
solution of the colouring matter and subsequently precipitating the colouring
matter with tannin.
Example 1. One part by weight of ponceau R is dissolved in 200 parts of water,
then 7 parts of sodium carbonate dissolved in water are added, subsequently a
solution of one part of alumina sulphate (free from iron) is added, afterwards
strontium chloride just sufficient in quantity to precipitate the colouring matter is
stirred into the mixture, which may be effected by 50 parts (by weight) of a
strontium chloride solution at 28° Bé. For this purpose the crude strontium
chloride solution obtained from ordinary strontianite, by neutralisation with some
dilute hydrochloric acid, may be used.
The lake or pigment thus obtained is filtered in the filter press and either used
directly as a paste, or it may be dried at a moderate temperature, ground and
strained. If in the above example we add to the solution of colouring matter
before precipitation two parts by weight of finely ground spar (barium sulphate)
rubbed through a fine sieve together with water, the shade and softness of the
resulting colour will not be altered.
Example II. 12 parts (by weight) of xylidin are dissolved in 27 parts of hydro-
chloric acid (at 20° Bé.) and 1000 parts of water, and diazotised with 7 parts of
nitrite dissolved in water, the temperature being kept low by the addition of ice
during diazotisation. To this diazo-solution 3000 parts of strontium chloride
solution at 28° Bé. are added while constantly stirring, and the mixture thus
obtained is poured into a solution of 40 parts of beta-naphthol-disulphonate of soda
(R-salt) and 430 parts of anhydrous carbonate of soda in 5000 parts of water,
while constantly stirring. The resulting colouring matter is filtered and treated as
described above.
If in the above described process the sodium carbonate be replaced by Glauber's
Galt, or another soluble sulphate, the use of strontium chloride yields strontium
sulphate, a white substance suitable specially for producing pigments or lakes.
The colours obtained with this body having a blueish hue. This body may be
produced by mixing an aqueous solution of the sulphate with an aqueous solution
of a soluble strontium salt in molecular proportions (for instance 142 parts hy
weight of anhydrous sodium sulphate to 158 parts of anhydrous stroutium chloride)
so as to obtain a precipitate. The manufacture of the strontium sulphate may take
place in the presence of coal tar dyes, especially azo-dyes, in which case the
colouring matter is precipitated simultaneously with the formation of the strontium
sulphate.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
_claim is.
1. The manufacture of pigments or lakes by means of artificial strontium
carbonate obtainable from sodium carbonate and a soluble strontium-salt, substan-
-tially as described.
2. The manufacture of pigments or lakes by means of the strontium salts of
caid coal-tar dyes, and in particular by means of the strontium salts of the above
mentioned azo-dyes ponceau (G, R, 2 R, 3 R), orange (II and crocein orange),
Bordeaux (S and R), true red (A, B, C, D, E, B T), true brown (O, N), benzo-
purpurin (B, 4B, 10 B), chrysamin (G and R), tartrazin, and natural flavin.

page_text: 3. The simultaneous manufacture of artificial strontium carbonate and of azo-
dyes, in particular those specified in Claim 2, as described in the second example
for the production of pigments or lakes.
4. The manufacture of artificial strontium sulphate from soluble sulphates and
soluble strontium salts for the purpose specified.
Dated this 30th day of August 1895.
FAIRFAX & WETTER,
433, Strand, London, Agents..