close

Вход

Забыли?

вход по аккаунту

?

Патент USA US2405031

код для вставки
Patented July 30, 1946
2,405,031
UNITED STATES PATENT OFFICE
2,405,031
-METHOD OF PRODUCING LUMINESCENT
ZINC SULPHIDE
1
Mac Goodman, New York, N. Y.
‘No Drawing. Application June 24, 1940,
Serial No. 342,077
10 Claims. (01. 252-3011;)
2
This invention relates to improvements in
luminescent compositions and methods of pro
ducing the same, being particularly directed to
?uorescent and phosphorescent zinc sulphide
products.
,
analogous classes, it has been essential not oi y
to carry out a calcination of the mix in
tion aforesaid, a quantity of a volatile salt prefer
5
Up to the‘present time in the manufacture of
luminescent compositions of the zinc sul
of zinc oxide and sulphur in stoichiometric pro
nortions referred to in my co-pending applica
non-
oxidizing or reducing atmosphere, Whether it he
that of zinc sulphide together with ?uxes
acti
vators on the one hand, or that of zinc oxide and
sulphur
in my co-pending
in stoichiometric
application,
proportions
Serial No.
as 336,831,
aably
solvent
in saturated
for the zinc
solution
oxide ofcapable
such mix,
of that
acting
upon
ignition the end product comprises a very light
and fluffy product of relatively very small crystal
size, qualities which give greater emission e?i~
ciency and adaptability for commercial use in
mixtures for paints or the like.
These and other advantages, capabilities and
features of the invention will appear from the
subjo ed detailed description of one speci?c em
bodiment thereof.
?led May 23, 1940, on the other hand, but in 15
In carrying out a preferred embodiment of my
commercial operations even with the greatest
process I form my mix by adding to stoichiometric
of care the presence of air or oxygen even in rela
proportions of Zinc oxide and sulphur as de?ned
tively small quantities in the ignition chamber is
in my aforesaid co-pending application, between
found to decrease the liminescence of the end
three-quarters of a mol and a mol of ammonium
product resulting from calcination by virtue .
the formation through-oxidation of deleterious
and unwanted byproducts.
I have found that by addition of volatile
to the mix, be it of the character of either the >
well-known Zinc sulphide-?uX-activator mix of
the prior art, as for example, a mix incorporating
zinc sulphide to which has been added a relatively
small amount of a flux such as sodium chloride
or sodium sulphate and a minute amount of an
activator such as copper or silver chloride or
nitrate or the zinc oxide and sulphur mix referred
to in my aforesaid co-pending application, I am
able to avoid oxidation during ignition through
20 carbonate, wl ,
quantity substantially is in
stoichiometric proportions with respect to the
zinc oxide and sulphur and ignite for a period of
o e-half hour to
hour at from 1100" to 1250" C.
I prefer to apply the ammonium carbonate, zinc
oxide~sulphur mix in saturated solution since
under such conditions the aforesaid volatile salt
acts‘as a solvent for the zinc oxide of the mix and
by such solvent action provides for the formation
to some extent of zinc carbonate on the one hand,
and undissolved zinc oxide of reduced particle
size on the other, as a result of which there pro
vided a more intimate mixture of the sulphur
and zinc oxide upon drying at temperatures of
between 100°-1?5° C. The composition of the
tion products of such volatile salts; which vapors
mass after drying contains sulphur and zinc oxide
or gases after development upon discharge from
and to
extent basic zinc carbonate.
the chamber scrub or sweep out any air or oxygen.
During ignition of the aforesaid mix at the
from the ignition chamber either
combined
temperature range between 110€l° and 125*)" C.
or uncombined therewith.
for a period of one-half hour to one hour, there
I have further found that ‘it
not necessary 40 is developed in
ignition chamber carbon
to tightly seal the ignition chamber against in~
dioxide, ammonium and water vapor, most of
gress of air, since with the development (it
which. is discharged from the ignition chamber as
ignition of the vapors or gases from the vola s
the reaction proceeds, carrying with it in a scrub
salts added to the mix aforesaid, a preponderance
g action the oxygen or air present in or enter
of the volume of the atmosphere in
ignition 45 ing the chamber; that portion of the developed
chamber comprises the vapors or
of the
vapors and gases remaining in the chamber serv»
volatile salts which by their nature are non-oxidiz
ing essentially to provide a non-oxidizing atmos
ing and which, being continually developed as the
phere in such. chamber.
During ignition, the relatively small quantity of
ignition procee
chamber, not
but only
as they
substantially
discharged
?ll
the development of vapors or gases as decomposi~
therefrom carry along in a'substantially scrubbing
effect any air or oxygen normally in the ignition
carbonate developed in the pre-ignition mix
ing
is broken down to form zinc oxide and
carbon diovide so that at the end of the calcina
chamber or entering into the same as the reac
tion period the crystals formed are luminescent
tion progresses.
zinc sulphide crystals in the distorted lattice
I have further found that by adding to the mix. 55 formation of which are occluded zinc oxide in
2,405,031
3
solid solution, as described in my copending ap
plication aforesaid.
Although I have referred to the use of am
monium carbonate as the volatile salt useful for
the purpose aforesaid, I may apply other inorganic
salts of the same character, as for example, am
and subjecting the mixture to ignition in a cham
ber, whereby the luminescent end product is
formed in the nonoxidizing atmosphere of car
bon dioxide and ammonia developed during the
reaction.
6. The method of forming a luminescent com
position, comprising admixing with zinc oxide
and sulphur capable of forming a luminescent
zinc sulphide upon calcination, a saturated so
monium bicarbonate and organic compounds as,
for example, urea, and thiourea, and any and all
other compounds which upon decomposition at
or below the ignition temperatures above speci?ed 10 lution of a volatile salt selected from the group
consisting of ammonium carbonate, ammonium
produce carbon dioxide, ammonia, or both, or
bicarbonate, urea, and thiourea, convertible by
gases or vapors of a non-oxidizing nature.
heating into carbon dioxide and ammonia, dry
It is obvious that various changes and modi?
ing the mixture and subjecting the mixture to ig
cations may be made to the details of construc
tion without departing from the general spirit 15 nition in a chamber, whereby the luminescent
end product is formed in the non-oxidizing at
of the invention as set forth in the appended
mosphere of carbon dioxide and ammonia de
claims.
veloped during the ignition reaction.
I claim:
7. The method of forming a luminescent com
1. The method of producing a luminescent com
position, comprising admixing with substances 20 position, comprising admixing with zinc oxide
and sulphur capable of forming a luminescent
incorporating zinc and sulphur capable of form
zinc sulphide upon calcination, a saturated solu
ing a luminescent zinc sulphide upon calcination,
a volatile salt convertible by heating into am
tion of a volatile salt selected from the group con
ignition reaction.
nition in a chamber within a range of tempera
sisting of ammonium carbonate, ammonium bi
monia vapor, and subjecting the mixture to igni
tion in a chamber whereby the luminescent end 25 carbonate, urea, and thiourea, convertible by
heating into carbon dioxide and ammonia, drying
product is formed in the non-oxidizing atmos
the mixture and subjecting the mixture to lg
phere of ammonia vapor developed during the
_
2. The method of producing a luminescent
tures extending from 1100" C. to 1250° C., Where
composition, comprising admixing with sub 30 by the luminescent end product is formed in the
atmosphere of non-oxidizing ammonia and car
stances incorporating zinc and sulphur capable of
forming a luminescent zinc sulphide upon calci
nation, a volatile salt of a group consisting of am
monium and amine compositions convertible by
heating into a non-oxidizing vapor, and sub
jecting the mixture to ignition in a chamber
bon dioxide developed during the reaction.
8. The method of forming a luminescent com
position, comprising admixing with zinc oxide and
35 sulphur capable of forming a ‘luminescent zinc
sulphide upon calcination, a saturated solution
of a volatile salt selected from the group consist
ing of ammonium carbonate, ammonuim bicar
bonate, urea, and thiourea, convertible by heat
3. The method of producing a luminescent 40 ing into carbon dioxide and ammonia, drying the
mixture and subjecting the mixture to ignition in
‘composition, comprising admixing with a sub
a chamber, and for a period of one-half hour to
stance incorporating zinc and sulphur capable of
an hour, whereby the luminescent end product
forming a luminescent zinc sulphide upon calci
is formed in the atmosphere of non-oxidizing am
nation, a volatile salt convertible by heating into
carbon dioxide and ammonia vapor, and sub 45 monia and carbon dioxide developed during the
reaction.
jectlng the mixture to ignition in a chamber,‘
9. In a method of forming a luminescent zinc
whereby the luminescent end produce is formed
whereby the luminescent end product is formed
in the non-oxidizing atmosphere developed dur
ing the ignition reaction.
sulphide, the steps which comprise mixing zinc
in the non-oxidizing atmosphere of carbon diox
oxide and sulphur crystals in stoichiometric pro"
ide and ammonia developed during the ignition
60 portions, ammonium carbonate, and heating be
reaction.
tween the temperatures of 1100° C. to 1250° C. for
4. The method of producing a luminescent
a period of one-half hour to an hour, whereby the
composition, comprising admixing with zinc ox
luminescent end product is formed in the at
ide and sulphur capable of forming a luminescent
mosphere of non-oxidizing ammonia and carbon
zinc sulphide upon calcination, a volatile salt con
vertible by heating into carbon dioxide and am 55 dioxide developed during the reaction.
10. In a method of forming luminescent zinc
monia vapor, and subjecting the mixture to ig
sulphide, the steps which comprise mixing zinc
nition in a chamber, whereby the luminescent end
oxide and sulphur crystals in stoichiometric pro
product is formed in the non-oxidizing atmos
portions and adding thereto in substantially
phere of carbon dioxide and ammonia developed
during the ignition reaction.
60 stoichiometric proportions, a saturated solution
of ammonium carbonate, drying and heating be
5. The method of producing a luminescent
tween the temperatures of 1100° C. to 1250° C. for
composition, comprising admixing with zinc ox
a period of one-half hour to an hour, whereby
ide and sulphur capable of forming a luminescent
the luminescent end product is formed in the at
zinc sulphide upon calcination, a volatile salt of
a group consisting of ammonium carbonate, am 65 mosphere of non-oxidizing ammonia and carbon
dioxide developed during the reaction.
monium bicarbonate, urea and thiourea, convert- '
ible into carbon dioxide and ammonia by heating,
MAC GOODMAN.
Документ
Категория
Без категории
Просмотров
0
Размер файла
319 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа