Note: Descriptions are shown in the official language in which they were submitted.
,~ ~ 3 2 ~ 2
1 -- ,
CAST DETE~SIVE SYSTEMS HAVING A _ ABLE HALOGEN
SOURCE IN THE PRESENCE OF READILY OXIDIZABLE ORGANICS
Field of the Invention -
The invention relates to a detersive system containing
soil removing detergents, an encapsulated halogen source
and an organic component such as a polyalkylene oxide
polymer, and to the use of the system in cleaning. More
specifically the detersive systems of the invention can
contain an active encapsulated halogen source and organic
component, preferably an alkylene oxide polymer, which are
co-stable at relatively high concentration during
manufacture, storage, distribution, sale and use. Such
detersive systems can be used in a variety of environments
including general purpose cleaning, laundry, warewashing,
etc., while producing an effective concentration of active
chlorine for stain removal and sanitizing purposes in the
presence of organic materials such as defoamers, soil
removing nonionic surfactants and other polyalkylene oxide
polymers.
Background of the Invention
Detersive systems have been used for many years in
cleaning environments such as laundry, warewashing, hard
surface cleaning and other general cleaning applications.
Typically detersive systems are concentrates comprising
mixtures of cleaning ingredients that, just prior to use,
are mixed with water to form a cleaning medium or final use
composition.
Many detersive systems contain organic materials that
function in a variety of modes. Such organics can act as
defoaming agents, dispersing agents, soil removing
sur~actants, thickening agents, casting aids, anti-
redeposition aids, viscosity modifiers, brightening agents,
etc. One important class of organic materiali~ is
polyalkylene oxide polymers. The polyalkylene oxide
polymers derive their propertles from the presence of large
polymeric units derived from ethylene oxide, propylene
1~32~ 02
- 2 -
oxide, heteric polymers thereoF or block copolymers
thereof.
In a variety of use environments for such detersive
systems, the presence of oxidizing available halogen such
as chlorine or bromine can be importan . Such halogen
compounds can clean and remove certain residues, and can
remove stains by oxidizing and destroying color generating
functional groups in organic molecules. Further, the
presence of suEficient concentrations of active chlorine
can kill microorganisms and provide an antimicrobial or
sanitizing action. However, detersive systems
manufacturers have been reluctant to produce detersive
systems in which organic materials such as polyalkylene
oxide polymers and active chlorine yielding substances come
into direct contact. Such contact can have undesirable
safety and perormance consequences.
In the manufacture of a variety of detersive systems,
contacting many organic substances with active chlorine
compounds is hazardous. At elevated temperatures or at
high concentrations, contacting such organic compounds with
active chlorine-yielding substances ca~res~t in a rapid
~ reaction between the chlorine substances and the organic
; materials resulting in the production of large volumes of
smoke or fire. If the detersive systems are successrully
marlufactured without rapid reaction between the chlorine
and polyalkylene oxide components, the materials during
manufacture, packaging, storage, distribution, sale and use
can slowly react causing a significant depletion in the
concentration of both the organic materia~s and the active
chlorine substance. Such reactions commonly occur at a
rate such that the concentration of active chlorine in the
detersive system is below the concentration necessary for
sanitizing properties and even is often below the
concentration required for stain removal. Further such
reactions can reduce the concentration of the organic
materials to a level that results in substantially reducing
the le;el of properties derived from the polymer.
~ 32~ ~2
-- 3
We have found that active halogen can be lost through
a spontaneous degradation of active chlorine and by
reactivity of chlorine with functional groups con~only
found in organics used in detersive systems. The co~non
functional groups reactive with active chlorine compounds
include o]efinic bonds commonly found in unsaturated fatty
acids which are a common composition of alkali metal soaps,
hydroxyl groups typically found in organic builders, amine
groups, ether groups common in polyalkylene oxide polymers
and aromatic rings typically ound in alkyl benzene
sulfonates, alkyl phenol ethoxylates, etc. The prior art
commonly kept the concentration of organics less than 5
wt-~ to reduce the harmful effects of the organic/chlorine
interaction.
Accordingly a substantial need exists in the art for
detersive systems containing signiEicant effective
concentra~ions (greater than 5 wt-~) of organic materials
in the form of surfactants, foam suppressing agents and
other functional materials, and containing effective
concentrations (greater than 5 wt-%) of active chlorine
from chlorine yielding compounds. ~~
Brief Description of the Invention
__. ~ : .. .....
We have found that a cast, solid detersive system
containing an effective amount of a source of alkalinity,
an effective hardness sequestering agent, at least 5 wt-%
of an encapsulated source of chlorine and at least S wt-%
of an organic such as polyalkylene oxide polymer is an
effective detersive system that can be used in general
purpose cleaning, laundry, warewashing, hard surface
cleaning and sanitizing, and a variety of other end uses.
We have surprisingly found that such materials when cast in
a solid form result in substantial stability of an
effective concentration of both chlorine and organic
materials during manufacture, storage, distribution and
use. We have found that for periods typical in the
lifetime of such a product, the products can maintain a
substantial concentration of active chlorine and an
3%~2
effective concentration of organics until the product is
entirely consumed.
Detailed Discussion of the Invention
The detersive systems of the invention can comprise an
effective amount of a source of alkalinity, an effective
amount of a hardness sequesterilg agent, at least 5 wt-~,
up to about 50 wt-~, of an encapsulated source of chlorine
compound, and at least 5 wt~%, up to about 50 wt-~, of an
organic composition such as a polyalkylene oxlde polymer.
The detersive systems of this invention are typically in
the form of a cast, solid material wherein the material is
in the form of a large, solid mass having a minimum weight
of about 50 grams held within a disposable container. The
detersive system or concentrate can be dispensed from the
container or can be removed fron~ its container and placed
into the dispenser for dilution and use at the use site.
Inorganic Source of Alkalinlty
The detersive systems of the invention can contain an
inorganic source of alkalinity. Sources of alkalinlty
ldentified as being useful in combination with the other
components of the detersive systems~- of the invention
include but are not limited to the following: alkali metal
hydroxide, alkali metal phosphate, alkali metal carbonate,
alkali metal bicarbonate, alkali metal sequlcarbonate,
alkali metal borate, alkali metal silicate, and mixtures
thereof. Alkali metal hydroxides are typically used where
the detersive system requires strong cleaning action and
highest pH. Silicates (M2O:Sio2 compounds having a ratio
from about 2:1 to 1:3.6 wherein M ls an alkali metal ion)
are typically a reaction product between an alkall metal
hydroxide and silica. Such silicates are primarily used as
a source of alkallnlty where moderate s,rength and pH are
requlred. Carbonate and borate sources of alkalinity are
typically used ln compositions having an alkaline pH but do
not requlre the strength of alkalinity of silicates or
hydroxldes.
.
~_ 5 _ ~2~
Hardness Sequesterina ~qen_s ~ ;
The detersive systems of the invention typically
contain a hardness sequestering agent to reduce the harm~ul
ef~ects of divalent and trivalent metal ions on the ~ ;
components of the detersive systems. The detersive systems
of the invention can contain both organic and inorganic
hardness sequestering agents. Such sequestering agents are
typically in the form of poiyanionic materials.
Inorganic hardness sequestering agents include alkali
metal condensed phosphates in the form of pyrophosphate,
tripolyphosphate, hexametaphosphate, etc. Organic hardness
sequesterin~ agents include polymeric and copolymeric
compositions having pendent carboxylic acid functionality
derived from carboxylic acid containing monomers such as
acrylic acid, methacrylic acid, maleic acid, itacanic acid,
fumaric acid and mixtures thereof, etc.; alkali metal salts
of organic substituted phosphonic acid and polyphosphonic
acids, alkali metal salts of gluconic acid, alkali metal
salts of ethylene diamine tetraacetic acid, alkali metal
salts of nitrilotriacetic acid, and mixtures thereof.
Orqanic Materials
A variety of organic functional materials can be used
in the detersive systems of the invention. Such functional
materials include absorbents, adsorbents, antimicrobials,
antioxidants, anti-soil agents, perfumes, dyes, binders,
chelating agents, corrosion inhibitors~ coupling agents,
defoamers, dispersants, solubilizers, stabilizers,
thickeners, and UV absorbers. Examples of such absorbents
and adsorbents are microcrystalline cellulose, zinc
ricinoleate, free-fIowing malto dextrin, powdered acrylate
copolymers, and others. Anti-soil or anti-soil
redeposition agents that can be used include fatty acid
amides, fluorocarbon surfactants, complex phosphate esters,
styrene maleic anhydride ~ copolymers, and cellulosic
derivatives such as hydroxyethyl cellulose, hydroxypropyl
cellulose, and others. Powder binders that can be used to
aid in the formation of solid materials include
~32~2
microcrystalline cellulose, long chain lactate esters, long
chain oleate esters, polyacrylamides, microcrystalline
waxes, polyvinyl alcohol resins, polyethylene, polyvinyl
pyrrolidone, and others.
Defoamers that can be used in the detersive systems of
the invention include high molecular weight C10 40 linear
primary alcohols, polyalkylene glycolsj well known silicone
defoamers, certain acrylate copolymers, and others.
One important class of functional organic materials in
the manufacture of detersive systems of the invention
- comprises organic surfactants. A wide variety of
surfactants can be used in the detersive systems of the
invention including anionic surfactants, zwitterionic
surfactants (containing both anionic and cationic groups),
cationic surfactants and nonionic surfactants. Anionic
surfactants include alkyl carboxylate (sodium and potassium
soaps), alkyl sulfate, alkyl ether sulfate, alkyl benzene
sulfonate, alkyl sulfonate, sulfonated fatty acid ester,
sulfosuccinate surfactant.
Nonionic surfactants typically in the form of
compositions having polyalkylene oxide polymers as a
portion of the surfactant molecule can be useful in the
detersive systems of the invention.
Nonionic surfactants which are advantageously employed
in the composition of this invention include, but are not
limited to, the following polyoxyalkylene nonionic
detergents: C8-C22 normal fatty alcohol-ethylene oxide or
propylene oxide condensates, i.e., condensation products of
one mole of a fatty alcohol containing 8 to 22 carbon atoms
with fro~ 2 to 20 moles of ethylene oxide or propylene
oxide; polyoxypropylene-polyoxyethylene condensates having
the formula HO(C2H4O)X~C3H6O)y~H wherein (C2H4O)X equals at
least 15~ and (C3H6O)y equals 20-90~ of the total weight of
the compound; alkyl polyoxypropylenepolyoxyethylene
condensates having the formula RO-(C3H6O)x(C~2H4O)y~ where R
is a Cl-C15 alkyl group and x and y each represent an
integer of from 2 to 98; polyoxyalkylene glycols as
, . ~ , . , ,: , : : , . : .
~ _ 7 _ ~32~2 ~
described in U.S. Pat. No. 3,048,548; butylene oxide capped
alcohol ethoxylates having the formula R~OC2H4)y(0C4Hg)xOEI
where R is a C8-Cl8 alkyl group and y is from about 3.5 to
lO and x is an integer from about 0.5 to 1.5; benzyl ethers
of polyoxyethylene condensates oE alkyl phenols having the
formula
R ~ (oc2H4)xocH2c6~
1 0 '' ' ~ """ '
where R is a C6-C2~ alkyl group and x is an integer of from ,h
5 to 40; and alkyl phenoxy polyoxyethylene ethanols havin~ ,,
the formula
R ~ ~OC2H4)xOH
where R is a C8-C2~ alkyl group and x is an integer of from
3 to 20.
Non-Surfactant Polyoxyalkylene Groups --
Nonsurfactant polyalkylene oxide polymers are used in
the manufacture of the detersive systems of the invention
as a binder or as a casting agent in which the materials o~
the invention are blended with the casting agent at ~;
elevated temperatures and ~the cooling of the blended
material solidifles the casting agent resulting in a stable
cast solid. Such polyalkylene oxide polymers comprise
homopolymers of ethylene oxide (EO), homopolymers of
propylene oxide (PO), heteric EO/PO copolymers or block
EO/PO copolymers, for example, those of molecular weight
from 1,000 to 10,000, especially about 6,000 to 8,000. ''
These materials are not to be considered as surfactant
35 materials in the context of the present invention. -
Additional,Inqredients ~
The detersive systems of the invention can contain ' , -
~ ~ - 8
anti-foaming agents, typically in an amount of from about
0.001% to about 2%, preferably 0.05 to 1~. Such foam
suppressing or foam regulating agents include silicone
compounds, phosphate esters, microcrystalline slack waxes,
etc. In somewhat greater detail, preEerred suds
suppressing agents are silicone mat-rials which are
siloxanes having the formula
R
- [ I i ~~ ] x
~' . .
wherein X is from about 20 to about 2,000 and R and R' are
each independently selected from the group consisting of
Cl_20 alkyl or alkyl substituted aryl groups. Preferred
groups include methyl, ethyl, propyl, butyl, and phenyl.
Polydimethyl siloxanes having a molecular weight in the
range of 200 to 200,000 and higher are useful suds
controlling agents. Other suds suppressing agents include
alkyl phosphate esters such as monostearyl phosphate and
microcrystalline waxes having a melting point from about
65 C. to about 100 C. and having a molecular weight from
400 to about 1,000.
The detersive systems of the invention can contain
neutral organic and inorganic fillers such as sodium
sulfate and sodium chloride. Organic fillers that can be
used in the invention include starch, sugars, alkylene
glycols having from 1 to 10 carbon atoms, etc.
Additionally the compositions can contain proteolytic and
amylolytic enzymes, tarnish inhibitors such as benzo-
triazol, antibacterial agents, anti-soil redeposition
agents, soil suspendin~ agents, dyes, perEurnes, and
silicate, glass and aluminum tarnish suppressing agents.
Method of Castinq the Detersive_Systems
The components of the detersive systems are typically
cast in a disposable container ~hich also acts as a mold.
~ 9 ~3~ 2
The detersive system can be dispensed from the container or
can be removed from the container prior to insertion in the
dispenser. Alternatively the detersive system components
can be cast in a reusable mold wherein the cast material is
removed from the mold and placed into a separate disposable
container for shipment and use.
The detersive system can be cast in virtually any
order of addition of materials to a mixing unit. Once
uniform the material for casting is then placed in an
appropriate mold.
A preferred mode of casting the material is to place
the low molecular weight and water soluble materials into a
mixing chamber in conjunction with any water used in the
manufacture of the materials. Next the higher molecular
weight or insoluble materials are slowly added to the
contents of the mixing unit until a uniform suspension is
obtained. Lastly the active halogen source can be added to
the mixture. The mixture is carefully agitated at a slow
rate such that the integrity of the encapsulate is not
compromised.
Encapsulate
The encapsulated sources of halogen of this invention
comprise a core of an active halogen compound and at least
one coating layer. Preferably the encapsulated sources of
halogen have a core and two or more coating layers. If one
layer is used it preferably comprises an inorganic co~ting
of a composition compatible with the halogen source,
however certain coatings of a synthetic detergent can be
used. If two layers are used the first layer comprises a
typically inert or inorganic coating agent and the second
layer comprises an organic layer or a synthetic detergent
layer.
Haloaen Source
The halogen releasing substances suitable as a core
material include halogen components capable of liberating
active halogen species such as a free elemental halogen or
-OX- wherein X is Cl or Br, under conditions normally used
~ 3 ~ 2
`, '- 10 -
-,
in detergent-bleaching cleaning processes. Preferably the
halogen releasing compound releases chlorine or bromine
species. The most preferred halogen releasing compound
` releases chlorine. Chlorine releasing compounds include
potassium dichloroisocyanurate, sodium dichloroiso-
cyanurate, chlorinated trisodium phosphate, calcium hypo-
chlorite, lithium hypochlorite, monochloroamin , dichloro-
amine, pentaisocyanurate, 1,3-dichloro-5,5-dimethyl
hydantoin, paratoluene sulfondichlo~o-amide,
; lO trichloromelamine, N-chloromelamine, N-chlorosuccinimide,
N,N'-dichloroazodi-carbonamide, N-chloro-acetyl-urea, N,N-
dichlorobiuret, chlorinated dicyandiamide,
trichlorocyanuric acid, and dichloroglycoluril.
, Sodium dichloroisocyanurate, potassium dichloroiso-
cyanurate and the dihydrates thereof are the most preferred
oxidizing chlorine source suitable as a core substance.
These materials are cor~lercially available and may be
obtained from sources such as Monsanto or Olin Corp.
Coatina Materials
The coating on the active halogen source can be a
single or multiple layer coating. 5~i`n~-le layer coatings
can comprise virtually any inert organic or inorganic
coating material stable with a halogen source that is solid
~` ~ at room temperature. In the instance that a multiple layer
coating is used, often the first layer is an inorganic
layer where the second layer comprises an organic layer -~
that can be drawn from a variety of sources.
Nearly any substance may be employed as the first
coating so long as it is substantially halogen inert and is
a solid at normal storage temperatures typicalLy between
30 and 100 F. (-1 to 38 C.). The coating material is
preferably inert with respect to the core material. If the
~ inner coating material is potentially reactive with the
¦~ core material~ the core material may be initially coated
,35 with an inert material to prevent or retard any eaction
between the core and this first coat, the initial coat
acting as a chemical barrler between the core and the flrst
,,
I
~ ~32~2
and other layers. Useful inorganics in the coating
material include alkalies such as sodium carbonate, sodium
bicarbonate, sodium sequicarbonate, sodium borate,
potassium bicarbonate, potassium sequicarbonate, potassium
borate, phosphates such as diammonium phosphates,
monocalcium phosphate, tricalcium phosphate, calcium
pyrophosphate, iron pyrophosphate, magnesium phosphate,
monopotassium orthophosphate, potassium pyrophosphate,
disodium orthophosphate, trisodium orthophosphate,
tetrasodium pyrophosphate, sodium tripolyphosphate, sodium
phosphate glass; neutral salts such as zeolites, sodium
sulfate, sodium chloride, and talc; silicates and silicate
hydrates such as sodium metasilicate, sodium sequisilicate,
dry sodium/potassium silicate water glasses, sodium
orthosilicate and mixtures thereof.
A useful initial inorganic coating compound for a
halogen bleach core material to be used in a detergent
composition would be an admixture o~ sodium sulfate and
sodium tripolyphosphate. Sodium sulfate and sodium
2Q tripolyphosphate are relatively inert with respect to
halogen bleaches and are components commonly blended into
detergent compositions.
Outer Coatinq Materials
Nearly any substance may be employed as the outer
coating material so long as it is solid at normal storage
tenperatures (typically between 30 and 100 F.). A
nonexhaustive list of compounds which ~may be used as the
second coat includes alkalies such as sodium carbonate,
sodium bicarbonate, sodium sequicarbonate, sodium borate,
potassium bicarbonate, potassium sequicarbonate, potassium
borate, sodium sulfate hydrate, phosphates such as
diammonium phosphates, monocalcium phosphate, tricalcium
phosphate, calcium pyrophosphate, iron pyrophosphate,
magnesium phosphate, monopotassium orthophosphate,
potassium pyrophosphate, disodium orthophosphate, trisodium
orthophosphate, tetrasodium pyrophosphate, sodium
tripolyphosphate, sodium phosphate glass; neutral salts
- 12 ~ 2
such as zeolites, sodium sulfate, sodium chloride, and
talc; silicates and silicate hydrates such as sodium
metasilicate, sodium sequisilicate, dry sodium/potassium
silicate water glasses, sodium orthosilicate; organic
sequestering agents such as copolymers of vinylacetate and
maleic anhydride, copolymers of acrylic acid and maleic
anhydride, copolymers of maleic anhydride and itaconic
acid, polyacrylic acid; and N-alkyl sulfona e, such as
octyl sulfonate, sodium car~oxymethyl celluloses,
hydropropyl cellulose, hydroxyethyl ether of cellulose,
hydroxypropylmethyl cellulose; C12 to C20 fatty acids such
as stearic acid, palmitic acid, and n-alkanoic acids;
paraffin waxes; microcrystalline waxes; C12 and greater
primary and secondary solid alcohols; Pluronic surfactants
with molecular weight between about 8,000 to about 16,500;
primary and secondary alkyl sulfates; and alkali metal
sulfonates and mixtures thereof.~ The preferred encapsulate
uses an outer coating that is insoluble in the liquid
composition prior to casting. After the detersive system
2G is cast, the preferred encapsulates are water soluble to
permit release of the halogen into the` c~ean~ling medium. ~-
The synthetic detergent compound used in the coating
must remain sufficiently solid at temperatures likely to be
encountered during storage of the product, for example,
temperatures of about 15 to 50 C., and also remain stable
at temperatures likely to be encounter~d during processing
of the product lnto end use mixtures, for example,
temperatures of about 15 to 95 C.
Synthetic deterjents that can be used include anionic,
cationic, nonionic and amphoteric detergent compositions.
Examples of anionic detergents useful in the detergent-
bleach compositions of the invention are the higher alkyl
mononuclear aromatic alkali-metal sulfates and sulfonates,
and linear alkyl sulfates and sulfonates such as
alkylbenzene sulfonates having about 9 to about 13 carbon
atoms in the alkyl group wherein the alkyl group is derived
from polypropylene as described by Lewis in U.S. Pat. ~o.
~ - 13 - ~32~02
2,477,382, or wherein the alkyl group is a hexene dimer or
trimer as in McEwan, U.S. Pat. No. 3,370,100, or wherein
the alkyl group is derived from alpha-olefins, as in
Swenson, U.S. Pat. No. 3,214,462. Also there may be
S employed primary and secondary alkyl sulfates.
The soaps are included within the definition o~
anionic detergents as used herein. Examples of operable
soaps soluble with the present invention are the sodium and
potassium salts of acyclic monocarboxylic acids naving
chain lengths of about 8 to about 22 carbon atoms.
A particularly suitable synthetic detergent for use as
a coating in the present invention is preoxidized sodium
octyl sulfonate. The sodium octyl sulfonate may contain
1,2 alkane bisulfonate as a by-product of manufacture which
does not affect the performance of sodium octyl sulfonate
as a coating in the invention.
The organic compound coating is applied as a solution
in a suitable solvent, water being preferred because o~ its
compatibility with chlorine releasing agents, non-
flammability, and non-toxicity.
The compositions of the presen~ nvention may be
formulated with a detergent builder as a de~ergency aid,
for example, those mentioned hereinaEter, to provide a
commercially valuable detergent-bleach co~position.
Inorganic fillers suitable for coating agents include
alkalies such as sodium bicarbonate, sodium sequicarbonate,
sodium borate, potassium bicarbonate, potassium sequi-
carbonate, potassium borate; phosphates such as diammonium
phosphate, monocalcium phosphate monohydrate, tricalcium -
phosphate, calcium pyrophosphate, iron pyrophosphate,
magnesium phosphate, monopotassium orthophosphate,~j-
potassium pyrophosphate, disodium orthophosphate,
dihydrate, trisodium orthophosphate, decahydrate, tetra-
sodium pyrophosphate, sodium tripolyphosphate, sodium
phosphate glass; neutral soluble salts such as sodium
sulfate and sodium chloride; silicates; organic seques-
tering agents; and anti-redeposition agents.
- 14 - 132~2
Nhen carrying out the process of the instant
invention, the protective encapsulate materials or coatings
of the invention are conveniently applied using fluidized
bed encapsulating equipment. Such equipment comprises a
coating chamber or cylindrical tower whereln the coating or
encapsulation of the particles is accomplished. A
unexpanded bed of the particles to be coated is introduced
into the equip~ent. A nozzle constituting a spraying means
is disposed within the equipment and adapted to be adjusted
vertically so that the liquid coating material discharged
in a downwardly diverging three-dimensional spray pattern
would just cover ~he upper surface area of the bed.
The coating solution is contained in a vessel and is
fed to the nozzle. Fluidizing gas (typically air) passes
into the fluidized bed area. The fluidized gas is heated
or cooled if r~quired, in order to maintain the fluidizing
gas within a desired temperature range,
A known weight of particles of a halogen source to be
coated is placed in the equipment. Air is caused to flow
into the fluidized bed thereby expanding the layer of
particles, and maintaining the parti~c-les~ in continuous
motion within the volume defined by the expanded bed, thus
forming a fluidized bed. A solution of a coating substance
is sprayed through the nozzle on the fluidized bed of
particles until all particles in the bed are completely
coated. Particles coated by the above-described procedure
are completely encapsulated with a continuous coating, and
are free-flowing and non-agglomerated.
It is important that each particle be fully covered to
prevent the oxidizing halogen source from reacting in the
- ~ detersive system environment.
When it is desired to apply an initial coating of a
coating agent and a subsequent coating of a synthetic
detergent, the double coating may be conducted in a single
fluidized bed either by applying the first coat, emptying
the solution tank, filling the solution tank with the
second coating solution and then applying the second coat;
~ ~2~2
- 15 -
or with a dual coâting solution inlet to the nozzle, the
fluidized particles in the bed first being coated with the
coating agent contained in a solution tank, this first
coating being allowed to dry and then a second coating of
the synthetic detergent contained in a second solution tank
being applied, both coatings being conducted in accordance
with the previous discussion on the operation of the
fluidized bed.
A third method of applying a double coating in a
fluidized bed is to coat the core particles with the
coating agent in a first fluidized bed apparatus. The
coated material is then allowed to dry and placed in a
second fluidized bed apparatus, wherein the encapsulated
product produced in the first fluidized bed is coated with
a second coating solution of a synthetic detergent. The
fluidized bed operation is conducted in accordance with the
prior discussion of the operation of the fluidized bed.
Before removal of the encapsulated oxidizing chlorine
source from the fluidized bed the temperature in the bed
can be increased so as to drive off any solvent remaining
in the encapsulate. However, the temper-a~ture must rema n
below the melting temperature of the encapsulant and below
the degradation temperature of the encapsulated core and
coatings.
The encapsulated halogen bleach sources of the present
invention comprise about 20 to 90 wt-~ halogen bleach
source core and about 10 to 80 wt-% coating when a single
coating is utilized, and about 20 to 90 wt-% halogen bleach
source core, about 0.5 to 50 wt-% inorganic coating agent
first coat, and about 5 to 70 wt-~ synthetic coating when a
double coating is utilized.
More particularly, the single coated halogen bleach
source comprises about 30 to 80 wt-~ halogen bleach source
core and about 20 to 70 wt-% synthetic coating and most
particularly about 40 to 55 wt-% halogen bleach source cor~
and 45 to 60 wt-~ synthetic coating.
A more preferred embodiment of the double coated
, -,, " "~; ;, : ", ., ,,.. , ," " ,
~L 3 ~ 2
- 16 -
halogen bleach source comprises about 30 to 80 wt-3i halogen
bleach source core, about 5 to 50 wt-% inorganic coating
agent first coating, and about 5 to 50 wt-~i synthetic
coating. In a most preferred embodiment, the encapsulat~
comprises about 30 to 60 wt-% chlorine bleach source core,
about 15 to 45 wt-~ inorganic coating agent first coating,
and about 10 to 35 wt-% detergent second coating.
Dispensina
The cast solid detersive systems of the invention can
be dispensed from a manual or automatic dispenser in which
a stream of water is contacted with a surface of the cast
material providing a concentrate that is directed to a use
location.
The cast material can be contained in a disposable
container and inserted into the dispenser in that form.
Alternatively the cast material can be maiually removed
from a disposable container directly into a dispenser
wherein the stream of water is contacted with at least one
surface of the material. Typical dispensers are mechanical
apparatus containing a nozzle for directing a stream of
water onto the solid cast materïa~ The dispenser
typically comprises a housing containing the internal
working parts. The housing typically includes a storage
portion wherein the mass of the solid block detersive
system can be supported. The dispenser contains typically
a support means upon which the cast material is placed.
The support is typically horizontally mounted within the
dispenser and maintains the block material in position
adjacent to the spray. The preferred support comprises a
screen mounted to the inner walls of the housing at a
position fixed above the spray such that the spray contacts
the majority of the solid cast detersive system. The
spray-forming nozzle is connected to a pressurized source
of water by means of a supply line. The spray is
controlled by a device that can demand the addition of the
concentrate made by spraying water on the cast material.
Upon the receipt of demand, water flow is directed through
.
- 17 -
the supply line and nozzle onto substantially the entire
lower surface of the cast material at pressures typically
greater than 10 psi. Heated water can be used depending on
the formulation. The use oE heated wa~er, all else being
equal, increases the rate of dispensing. The detersive
system passes in solution form through the support screen
and is directed by underlying collector portion of the
housing to an outlet port and through a conduit to a
utili~ation point. The utilization point can be a
warewashing machine, a station for charging containers such
as buckets or other apparatus with a concentrate for
dissolution with additional quantities of water, or other
use positions.
Alternatively the dispensing apparatus can be manually
operated such that a measured amount of concentrate can be
produced by manually triggering the spray onto the cast
material.
We have found that the stability of the chlorine
source in the presence of the organic compositions relates
to the quantity of free water in the cast material. We
have found that the detersive systems~du~ring manufacture
require some water fo~ processing. Preferably all water
present in the detersive system after casting is in the
form of bound water or water of hydration or complexed
water which is sequestered and removed from reactivity with
the components. Free water is water available for reaction
with the encapsulated chlorine material and can provide a
medium of reaction between released chlorine and any
organics present in the cast material. We have found that
maintaining the concentration of free water below about 10
wt-% can aid in preserving the availability of chlorine in
the cast material over a substantiaL period of time,
preferably maintaining the concentration of free water at
less than 5 wt-% or most preferably less than 2 wt-~ can be
very effective in maintaining the stability of the
material.
Exam~le I
. i ~ . : ~ .. . .. .... .
~32~ ~2
- 18 -
Chlorinated General Purpose Cleaner
Into a stainless steel jacketed tank equipped with a
variable speed turbine agitator WAS charged 10 parts of soft
water which was heated to 170F. Into the mixed water was added
20 parts of a polyethylene glycol (CARBOWAX* 8000, Union Carbide)
at a sufficient rate to dissolve the CARBOWAX in the water.
Agitation was ended and into the tank was placed 22 parts of a
linear alkyl benzene sulfonate, 4 parts of a polyacrylic acid
polymer (GOODRITE* K-7058D, B.F. Goodrich), 14.5 parts of a
powdered sodium tripolyphosphate, and l part of a granular sodium
tripolyphosphate, 14 parts of anhydrous sodium metasilicate and
6 parts of sodium bicarbonate. The product was cooled to a
temperature below 145~F. Next, 8.5 parts of an encapsulated
sodium isocyanurate (of Example II) is added to the tank and the
contents of the tank are carefully agitated at a temperature
below 145F. in a manner such that the encapsulate is evenly
distri~uted throughout the product. The material is drawn from
the tank and 2 lbs. of the warm liquid material is placed in
polyethylene containers. The containers and their contents are
cooled in an air chiller for 12-15 minutes at a temperature less
than 1~F and are solidified.
Example II
The encapsulated sodium dichloroisocyanurate used in
Example I was prepared as follows. Into a cylindrical fluidized
bed encapsulating machine was placed 61.25 parts of sodium
dichlorisocyanurate. The particles were fluidized and suspended
in air by an upwardly moving stream of air at a temperature of
about 90C. Onto the heated suspended particulate was sprayed
a solution comprising in 68.97 parts of soft deionized water,
16.5 parts of sodium sulfate and 5.5 parts of sodium
tripolyphosphate. The addition of this solution creates a first
inorganic layer of mixed sodium sulfate and sodium
tripolyphosphate. After the complete addition of the inorganic
layer, a solution comprising 49.62 parts of a sodium linear alkyl
sulfonate
*Trade-mark
.
', ' . , ~, , ' ' , , .
, , , , ,' i' ~ ,: ' ' `': '
~L32~ ~2
-- 19 --
in 49.62 parts of soft water is then sprayed on the
fluidized particle. This second step created an organic
encapsulate layer on the exterior of the particle.
Substantially all free water (about 151.5 parts were
removed~ was removed during encapsulation.
Example III
A chlorinated solid laundry detergent was made
according to the following procedure. Into a stainless
steel mixing tank equipped with heating and cooling and a
variable speed turbine agitator was placed 20 parts of a
nonylphenol ethoxylate having an average of 9.5 moles of
ethylene oxide, and 0.6 part of hexylene ~lycol. The mixer
is begun and into the tank is charged 11.35 parts of a
polyethylene glycol (CARBOWAX 8000, Union Carbide) at a
rate such that the polyethylene glycol melts and dissolves
in the liquid phase. In a separate container 2.3 parts of
soft water, 0.1 part of a fluorescent brightener and 0.004
part of a blue dye were mixed and then charged to the tank.
The temperature of the charged mater;als was permitted to
fall below 150 F. In a separate dry ~lender 0.5 part of
carboxymethyl cellulose, 27.246 ~-~parts of sodium
tripolyphosphate powder and 9.4 parts of anhydrous sodium
metasilicate were dry blended. The dry blend was slowly
added to the liquid phase in the mixing tank. After
uniformity was reached, 0.25 part of a fragrance was added.
The mixture was cooled and to the carefully agitated
mixture was added 19 parts of a chlorinated isocyanurate
manufactured in Example IV with 5 parts oE sodium
carbonate. The agitation was controlled such that the
encapsulate was just distributed throughout the product and
terminated. The material was packaged in 4 lb. aliquots in
polyethylene tubs and cooled until solid.
Example IV
Using the procedure of Example II the following
encapsulate was prepared.
':
:
'~ - 20 - ~3~
Ingredient Parts bv Weiqht
Core:
Sodium dichloroisocyanurate 63.2
Coating 1:
Sodium sulfate 25.8
Sodium tripolyphosphate 8.6
Soft water 103.0
Coating 2:
Hydroxypropyl cellulose 4.9 -;
Soft water 98.4
Water removed during encapsulation 203.9
xamel~ Y ;~
Using the procedure of Example II an encapsulated
15 chloxine source was prepared usin~ the following :
ingredients.
Ingredient Parts by_Weiqht :~
Core: ~ ;
Sodium dichloroisocyanurate 80.65 -
:
Coating 1:
Sodium sulfate 14.73
: Sodium tripolyphosphate 4.33 ;~
Soft water 58.68 .
25 Coating 2: ~-
Carboxymethyl cellulose 5.Q0
Soft water 88.8Q
Water removed during encapsulation 351.27
Example VI
: Using the procedure of Example II an encapsulated
chlorine ~ source was prepared using the following
ingredients.
,
` . .
~ 3 ~ 2
- 21 -
Inqredient Parts by ~eiqht
Core:
Sodium dichloroisocyanurate 63.2
Sodium sulfate 25.8 : -
Coating 1:
Sodium tripolyphosphate 8.6
Soft water 103.0 ~:
Coating 2:
Hydroxyethyl cellulose 4.9 :
Soft water 98.3
~ater removed during encapsulation 203.3
_amDle VII
An encapsulated chlorine source was prepared using the
15 procedure of Example II using the following ingredients. :
_qredient Parts by Weiqht
Core:
Sodium dichloroisocyanurate 63.2
Coating 1:
Sodium sulfate 25.8
Sodium tripolyphosphate 8.6
: Soft water 103.0
Coating 2:
Methyl cellulose 4.92
Soft watex 245.92
Water removed during encapsulation 351.46 :
Example VIII :
A solid chlorinated fabric softening laundry detergent :
was prepared following the procedure of Example III using
the following ingredients.
. . . , , ~ .
, ~ . . : , . ;
.. ~ . . . .. .
- 22 -~ 3 2~ 02
Ingredient Parts bv Weiqht
Nonylphenol ethoxylate 26.39
with 9.5 moles ethylene oxide
Hexylene glycol 1.17
5 Polyethylene glycol 14.6
SoEt water 2.-'5
Dye 0.08
Sodium tripolyphosphate 26.39
Sodium metasilicate 3.81
10 Quaternary ammonium fabric softener 2.25
Encapsulate of Example VI23.00
':
Exam~le IX
Example VI was repeated with the encapsulate of
Example II.
Example X
Example VIII was repeated with the encapsulate of
Example V.
Example XI
20Example VIII was repeated with the encapsulate of
Example VII.
,
Table 1 ~ :~
Active Chlorine Stability
25Percent Active Chlorine Retained After :
Storaqe at 100 for Two Weeks
Preparation Percent Retained
Example VIII 67.2
30 Example IX 57.5 :
Example X 62.8
Example XI 85.2
. :
Example XII
35Chlorinated General Pur~ose Cleaner
Into a stainless steel mix tank equipped with heating
and cooling equipment and a variable speed turbine type
: . . . . . . .
- 23 - ~3~02 -~
, :~
agitator was added 10 parts of water and 22 parts of
polyethylene glycol (CARBOWAX 8000). The glycol was added
at a rate such that it was melted and fully mixed upon
addition. Into the heated solution was added 20 parts of a
linear alkyl sulfonate, 4 parts of a polyacrylate polymer,
15.5 parts of sodium tripolyphosphate, 14.0 parts of sodium
metasilicate, and 6 parts of sodium bicarbonate. The
contents of the mixer were agitated until uniform and into
the mixer was added 8.5 parts of the encapsulate cf Example
II. The contents of the mixer were carefuIly agitated
until just uniform. The material manufactured above had a
chlorin,e stability of 106.06~ chlorine retained at 100 F.
for two weeks of storage.
Table 2 ~ -
Dispensinq Characteristics of Product oE ExamPle XII
Grams Dispensed
_lAveraqe of 5 Tests~
Temperature At 30 ~si At 50 ~si
120 34.338 53.735
130 38.72 59.2
140 50.68 66.184
~ 55-44 81.7
The data in Table 2 shows that the product of Example XII
is easily dispensed using warm water at commonly available
temperatures at commonly available pressures at most end
use sites. The product can easily be dispensed for any
typical end use by controlling either pressure, temperature
or dispensing time.
The product was dispensed by placing the material in a
dispenser using a 30-second cycle at either 30 or 50 psi
and at temperatures ranging from 120-150 F.
A useful dispenser is shown in FIGURE 1. Referring to
Fig. 1, there is generally disclosed a dispenser having a
container or housing 20. The housing has a generally
cylindrical upper storage portion 21 having a cylindrical
.
24 ~ 2
inner wall 22. The wall 22 defines an internal cavity 23.
The upper terminous of the storage portion 21 defines an
access port 24 into cavity 23 of storage portion 21~
Inner wall 22 of housing 20 converges in the downward
directionl defining a lower funnel-shaped collector portion
of housing 20. Inner wall 22 of housing 20 is
configured to form an annular flange at 26
circumferentially extending around inner wall 22 of housing
20 at the juncture of upper storage portion 21 and lower
collector portion 25. The lower terminous of collector
portion 25 defines an outlet port 27 from internal cavity
23 for passage therethrough of solution collected by
collector portion 25. Outlet port 27 has a hose clamp
extension 28 having a plurality of annular ribs configured
for engaging the inner walls of a connecting hose or
conduit 2~.
~ he outlet port 27 may be directly connected with the
wash chemical solution utilization point by conduit 29 and
feed thereto by gravity as it is created or feed thereto by
a wash chemical solution pump 30 placed in conduit 29.
Housing 20 may be constructed-of~ a~y suitable material
which is capable of withstanding exposure to cleaning
solutions, and is preferably configured of stainless steel
or molded plastic material. The housing 20 can ~e
constructed of a transparent or translucent material to
allow the operator to see at a glance the amount of wash
chemical in storage portion 21 and if dispenser 20 needs to
be refilled. If housing 20 is not made of a transparent or
translucent material, preferably a portion of storage
portion 21 is made transparent or translucent to aid in
determining when dispenser 20 should be refilled. A pair
of mounting plates 32 are connected to and extend
rearwardly from the outer surface of housing 20 for
securely mounting housing 20 to a vertical side wall.
A door 34 is sized to extend entirely across and to
sealingly close access port 24. Door 34 is pivotally
mounted at 35 for pivotai motion between a closed and
~ 25 - ~3~ 2
opened position. The lower collector portion 25 of housing
has an outwardly projecting coupling portion 36
extending from collector portion 25 adjacent outlet port 27
of collector portlon 25. A tube fitting insert 37 is
secured within coupling projection 36 and projects through
inner wall 22 of collector portion 25 of housing 20. A
spray-forming nozzle 38 is threaded into the end oE tube
insert 37 and is axially aligned within inner cavity 23 of
housing 20 in a direction so as to direct an upwardly
projected spray pattern therefrom. Tube fitting insert 37
is provided with an O-ring seal 39.
A horizontal support screen 40 is mounted in resting
engagement upon annular flanged portion 26 of housing 20.
Support screen 40 has about 1 inch square openings in order
to support a solid block o detersive system 80 without
significantly interfering with the impingement of water
sprayed from nozzle 38 onto the lower surface of water
sprayed from nozzle 38 onto the lower surface 81 of the
detersive system 80 (i.e., the surface in contact with
support screen 40).
A 1/4 to 1/20 inch (0.63 to 0.13 cm~) lower screen 41
is placed in collector portion 25 of housing 20 between
spray nozzle 38 and outlet port 27 to catch any undissolved
chunks of wash chemical 80 small enough to pass through
support screen 40. This prevents small chunks o~ chemical
80 collecting in outlet port 27 or conduit 29 and blocking
the flow of concentrated wash chemical solution out of
dispenser 20.
A water supply inlet pipe 42 is connected to tube
insert 37 and is in communication therewith for providing a
source of water flow to spray-forming nozzle 38. Water
supply line 42 passes through one of the mounting plate
members 32 and receives structural support therefrom. A
siphon breaker 43 interrupts water supply line 42. A
safety switch 50 is mounted to door 34 for movement
therewith and senses the operative position of door 34
relative to access port 24 of housing 20. In the preferred
, . ' , '. ' , ' ~ . '
13291 02
, ~
- 26 -
.
embodiment, safety switch 50 comprises a mercury actuated
switch.
FIGURES 2 and 3 represent an embodiment of the product
format for the cast detersive systems of the invention.
S The solid cast detersive system o. the invention is
packaged in a closable contalner 200 which comprises a lid
210 and a lower container section 211. The lid 210 can be
made of a variety of materials including paper, film, foil,
etc. The lower container can also be made of a variety of
materials, however thermoplastic deformable material is
preferred. The lid 210 is adhered to the container 211
through a releasable layer 212 disposed between the lid and
the container.
FIGURE 3 shows a side view of the cast detersive
system within its container. In use lid 210 is peeled from
the top oE the lower portion revealing the upper surface of
the cast material 80. The container as a whole without the
lid can be inserted into the dispenser. Alternatively the
container body 211 if made of a deformable material can be
flexed for the purpose of removing the cast material 80 in
a solid block which can then directly be inserted into the
dispenser for contact with a water stream.
While the foregoing discussion, Examples and data
provide a basis to understand the invention, many
embodiments of the invention can be made without departing
from the spirit and scope of the invention. Thus the
invention resides in the claims hereinafter appended.
,.
