Note: Descriptions are shown in the official language in which they were submitted.
3~
This invention re]ates to detergent compositions
which are useful for washin~ synthetic organic polymeric
fibrous materials, such as polyesters, and which impart soil
releasing properties to such washed materials. More particu-
larly, the invention relates to such compositions in parti-
culate form which contain as the soil releasing agen-t therein a
copolymer of polyethylene terephthalate and polyoxyet'nylene
terephthalate, a nonionic detergent, an alkaline builder which
can decrease the soil releasing effectiveness of the soil
releasing material when in contact wi-th such material during
storage, and a stabilizing proportion of polyvinyl pyrrolidone
(PVP) to help to maintain the soil releasiny characteristics of
the soil releasing copolymer despite the presence of the
alkaline builder.
In our Canadian Patent Application Serial ~o. 432,116
there are described built nonionic synthetic organic detergent
compositions which contain a preferred type of soil releasing
copolymer of polyethylene terephthala-te and polyoxyethylene
terephthalate. When polyester or polyes-ter-cotton blend
fabrics and items made From such fabrics have been washed in
the described products such fabrics acquire soil releasing
proper-ties so that when -they are subsequently soiled with a
lipophilic material, such as dirty motor oil, such soil can
more readily be removed during washing of the fabric,
whether such washing is with the invented detergent composition
or with a conventional Laundry detergent product. It has been
proposed to dissolve the mentioned type of soil releasing poly-
mer of polyethylene terephthalate and polyoxyethylene tereph-
thalate in molten nonionic detergent and to spray the solution
onto absorbent spray dried beads of builder material. The
described compositions and the me-thod for -the manufacture
thereof are useful but in some cases, as when the builder is
alkaline, its presence can adversely affect the soil releasing
capability of the soil releasing polymer in the mentioned
detergent compositions, after storage at room temperatures and
especially after storage at elevated temperatures. This
appears to be due to the sensitivity of the soil release pro-
moting polymer to hydrolysis. It has now been discovered that
when PVP, preferably of a certain type (molecular weight
range), is present in the detergent composi-tion in intimate
contact with the soil releasing polymer, sometimes coating it,
the soil releasing capabili-ty of the detergent composition
containing such polymer is significantly improved after stor-
age, compared to a similar product in which no PVP is present.
In accordance with the present invention a particu-
late built nonionic synthetic organic de-tergent composition for
washing synthetic organic polymeric fibrous materials and im-
parting soil release properties to them comprises a detersive
proportion of a nonionic synthetic organic detergent~
a bullding proportion of a water soluble alkaline builder for
such detergent, a soil releasing proportion of a soil releasing
polymer of polyethylene terephthalate and polyoxyethylene tere~
phthalate, and a stabilizing proportion of polyvinyl pyrrolidone
(PVP) for stabilizing the soil releasing polymer in the presence
of the alkaline builder. In another aspect, the present inven-
tion provides a process for manufacturing a particulate built
nonionic synthetic organic detergent composition for washing syn-
thetic organic polymeric fibrous materials and imparting soil re-
lease properties to them, which composition includes a detersiveproportion of a nonionic synthetic organic detergent, a building
proportion of a water soluble alkaline builder for such detergent,
a soil releasing proportion of a soil releasing polymer of poly-
ethylene terephthalate and polyoxyethylene terephthalate, and a
stabilizing proportion of PVP for stabilizing the soil releasing
polymer in the presence of the alkaline builder, which comprises
spray drying an aqueous crutcher mix of the alkaline builder to
produce dried particles thereof, and applying to such spray
dried builder particles either (i) the nonionic detergent in
liquid state containing the soil releasing polymer and the PVP,
so that the nonionic detergent, soil releasing polymer and PVP
are absorbed by the spray dried builder particles, or (ii) the
nonionic detergent in liquid state so that it is absorbed by the
spray dried builder particles, applying PVP in a liquid medium
to particles of the soil releasing polymer and mixing such re-
sulting particles with the builder particles containing nonionic
detergent.
Preferably the water soluble alkaline builder salt will
be sodium tripolyphosphate (normally pentasodium tripolyphosphate),
which may be accompanied by sodium silicate, a certain type of
polymer of polyethylene -terephthala-te and polyoxyethylene tere-
phthalate will be used, the nonionic detergen-t will be a con-
densation product of higher fatty alcohol and ethylene oxide,
and the PVP will be water soluble and within a given molecular
weight range. Limited proportions of moisture and adjuvants may
also be present in the invented compositions. Also within the
invention are processes for the manufacture of the described
stabilized soil releasing detergent compositions, and methods
for washing materials with such compositions.
Although various nonionic de-tergents of satisfactory
physical characteristics may be utilized, including condensa-
tion products of ethylene oxide and propylene oxide with
each other and with hydroxyl-containing bases, such as nonyl
phenol and Oxo-type alcohols, for best results it is highly
preferred that the nonionic detergent be a condensation
product of ethylene oxide and higher fatty alcohol. In such
- 4a -
3~
products the higher fatty alcohol is of 10 to 20 carbon
atoms, preferably 12 to 15 or 16 carbon atoms, and the
nonionic detergent con ains from about ~ ~o 20 or 30 ethylene
oxide groups per mole, preferably from 6 to 11 or 12. Most
preferably, the nonionic detergent will be one in which the
higher fatty alcohol is of about 12 to 15 or 12 to~14 carbon
atoms and which contains from 6 or 7 to 11 moles of ethylene
oxide. Among such detergents is Alfonic~l2l4-6oc~ sold by
the Conoco Division of ~.I. DuPont de Nemours, Inc., and
Neodols 23-6.5 and ~5-7, available from 5hell Chemical
Company. Among their especially attractive properties, in
addition to good detergency with respect ~o oily and greasy
soil deposits on goods to be washed, and excellent compatibi-
lity with the present polymeric release agents, is a compara-
tively low melting point, which is still appreciably above
room temperature, so that they may be sprayed onto base
beads as a liquid which solidifies quickly after it has
penetrated into the beads (m.p. usually being in 40 to 55C. ran~e).
Various builders and combinations thereof which
are effective to complement the washing action of the nonionic
synthetic organic detergent(s~ and to improve such action
include both water soluble and water insoluble builders. Of
the water soluble builders, which preferably are employed in
this invention, and are preferably in mixture, both inorganic
and organic builders may be useful. Among the preferred
3~
inorganic water soluble builders those that are best include :
various phosphates, preferably polyphosphates, such as the
tripolyphosphates and pyrophosphates, more specifically the
sodium tripolyphosphates and sodium pyrophosphates, e.g.,
pentasodium tripolyphosphate, tetrasodium pyrophoSphate;
sodium carbonate, preferably as soda ash; and sodium silicate;
and mixtures thereof. The sodium silicate is normally of
Na2O:SiO2 ratio within the range of 1:1.6 to 1:3, preferably
1:2.0 to 1:2.4 or 1:2.8, e.g., 1:2.4. Of the water soluble
inorganic builder salts the phosphates will usually be
employed in greater proportion, with a lesser proportion of
sodium silicate, the carbonate may be employed with bicarbonate
and often with a lesser proportion of sodium silicate, and
the silicate will rarely be used alone. Instead of individual
polyphosphates being utilized it will sometimes be preferred
to employ mixtures of sodium pyrophosphate and sodium tripoly-
phosphate in proportions within the range of 1:10 to 10:1,
preferably 1:5 to 5:1. Of couxse, it is recognized that
changes in phosphate chemical structure may occur during
crutching and spray drying, so that the final product may
differ somewhat from the components charged to the crutcher.
It will be noted that the water soluble builders
mentioned are alkaline materials and usually the alkalinity
resulting will be such that a 1~ aqueous solution of the
detergent composition will be of a pH in the range of about
3~
8.5 to 12, e.g., 10Ø This alkalinity helps the detergent
composition to remove various types of soil from laundry and
to hold it in suspension but it also has a negative effect,
tend.ing to cause degrada~ion of the soil releasing polymer
S employed and thus interfering with such polymer i~par~ing
50il releasing properties to washed materials.
Because polyesters, whe~her employed alone or in
blends with cotton, are lipophilic, they tend to attract and
hold lipophilic soils, which consequently may still be
present on laundry after washing, rinsing and drying.
Therefore, especially with respect to polyester fihers,
the imparting of soil release properties to the fibers of
materials being washed is important so that the laundering
thereof may be effective. Consequently, especially because
in recent years many articles of clothing and o~her washable
household goods have been made from polyesters or polyester
blends it is important that maximum soil release properties
be imparted to such material. Therefore, any tendency of
the soil releasing polymer being employed to degrade should
be counteracted. Thus, the discovery that a certain material
(PVP) s~abilizes the soil releasing polymer employed in this
invention is an important one.
The soil release promoting polymer which is an
essential component of the compositions of this invention is
a polymer of polyethylene terephthalate and polyoxyethylene
terephthalate which is dispersible in water and is depositable
3'7~
from wash water containing nonionic detergent and builder
for the nonionic detergent, onto synthetic organic polymeric
fibrous materials, especially polyesters and polyester
blends, so as to impart soil release properties to them,
while maintaining them comfortable to a wearer of clothin~
made from such materials and not preventing or significantly
inhibiting vapor transmission throuyh such clothing. Such
polyesters have also been found to posses~ anti-redeposition
properties and often assist in removing stains from substrates.
They tend to maintain soil, especially oily or greasy soil,
dispersed in wash water during washing and rinsing, so that
it is not redeposited on the laundry. Useful such products
are copolymers of ethylene glycol or other suitable source
of ethylene oxide moiety, polyoxyethylene glycol and tere-
phthalic acid or suitable source of the terephthalic moiety.The copolymers may also be considered to be condensation
products of polyethylene terephthalate, which may sometimes
be xeferred to as an ethylene terephthalate polymer, and
polyoxyethylene terephthalate. While the terephthalic
moiety is preferred as the sole dibasic acid moiety in the
polymer it is within the invention to utilize relatively
~mall proportions of isophthalic acid and/or orthophthalic
acid (and sometimes other dibasic acids, too) to modify the
properties of the polymer. However, the proportions of such
acids or sources of such supplemental moieties charged to
the reaction mix, and the corresponding proportions in the
-- 8 --
~2~3~7~
final polymer will normally be less than 10% each of the
total phthalic moieties present, and preferably will be less
than 5% thereof.
The molecular weight of the polymer will be in the
range of about 15,000 to 50,000, preferably being about
19,000 to 43,000, more preferably being about l9,000 to
25,000, e.g., about 22,000. Such molecular weights are
weight average molecular weights, as distinguished from
number average molecular weights, which, in the case of the
- 10 present polymers, are often lower. In the polymexs utilized
the polyoxyethylene will be of a molecular weight in the
range of about 1,000 to 10,000, preferably about 2,500 to
5,000, more preferably 3,000 to 4,000, e.g., about 3,400.
In such polymers the molar ratio of polyethylene terephthalate
to polyoxyethylene terephthalate units (considering
OCH2CH2O-C- ~ -C3 and ~(OCH2CH2)n-O-C- ~ -C~
as such units) will be within the range of 2:1 to 6:1,
highly preferably 5:2 to 5:1, even more preferably 3:1 to
4:1, e.g., about 3:1. The proportion of ethylene oxide to
phthalic moiety in the polymer will be at least 10:1 and
often will be 20:1 or more, preferably being within the
range of 20:1 to 30:1 and more preferably being about 22:1.
Thus, it is seen that the polymer may be considered as being
essentially a modified ethylene oxide polymer, with the
phthalic moiety being only a minor component thereof,
3~
whether calculated on a molar or weight basis. It is considered
surprising that with such a small proportion of ethylene
terephthalate or polyethylene terephthalate in the polymer
the polymer is sufficiently similar to the polymer of the
polyester fiber substrate (or other polymers to w~ich it is
adherent, such as polyamides) as to be retained thexeon
during the washing, rinsing and drying operations. Yet, as
shown by comparative experiments and various washing tests
in which soil release is measured, the described polymer, in
the present detergent compositions, is effecti~e to deposit
on washed synthetics, especially polyesters, so as to make
them better able to be washed free of oily soil by a built
nonionic detergent composition or other detergent product.
It is considered that the polymer's increased hydrophilicity,
attributable to the large proportion of hydrophilic ethylene
oxide moieties therein, may be responsible for the excellent
soil release properties which it imparts to the material
upon which it is deposited, and such may also help it to
coact with the built nonionic detergent.
Various li~erature articles, texts and patents
disclose methods for the manufacture of the present polymers,
included among which are Journal of Polymex Science, Vol. 3
pages 609-630 (1948); Journal of Polymer Science, Vol. 8,
pages 1-22 (1951); Fibers ~rom Syn~hetic Polymers, by Bill,
published by Elsevier Publishing Company, New York, New Yor~
(19~3), at pages 320-322; British patents 1,088,984 and
-- 10 --
~2~ 7~L
1,119,367; and U.S. patents 3,557,039; 3,893,929; and
3,959,230. Although suitable methods for making the instant
polymers are described in such references it is considered that
none of them discloses the particular polymers which are
utilized in the present invention (but some such are available
commercially) and none discloses the present detergent composi-
tions. Such polymers may be considered as having been randomly
constructed from polyethylene terephthalate and polyoxyethylene
terephthalate moieties, such as may be obtained by reacting
polyethylene terephthalate (e.g., spinning grade) and polyoxy-
ethylene terephthalate or reacting the ethylene glycol, poly-
o~yethylene glycol and acid ~or methyl ester) precursors there-
of. Yet, it is also within the invention to utilize more
ordered copolymers, such as those made by reacting components
of predetermined or known chain lengths or molecular weights,
so as to produce what might be referred to as block copolymers
or non-random copolymers. Graf-t polymers may also be practic-
able.
The described materials are available from various
sources, the products of one of which will be described in more
detail here. Useful copolymers for the manufacture of the
detergent compositions of this invention are marketed by
Alkaril Chemicals, Inc., and commercial products of such
company that have been successfully employed to produce
--1 1--
, ~
."
~J~3~4
satisfactory soil release promoting detersent compositions
are those sold by them under the trademaxks Alkaril QCJ ~nd
Alkaril QCF, formerly Quaker QCJ and Quaker QCF. Products
available from them in limited quantities, designated by
them as 2056-34B and 2056-41, have also been found to be
acceptable. The QCJ pxoduct, normally supplied as an aqueous
dispersion, is also available as an essentially dry solid (QCF).
When it is anhydrous or low in moisture content (preferably
less than 2% moisture), it looks like a lisht brown wax, and
in it the molar ratio of ethylene oxide to phthalic moiety
is about 22:1. In a 16% dispersion in water the viscosity
at 100C., is about 96 centistokes. The 2056-41 polymer is
like a hard, light brown wax and in it the hydrophile:
hydrophobe ratio is about 16 to 1, with the viscosity being
about 265 centistokes. The 2056-34B polymer appears to be a
hard brown wax, with a hydrophile.hydrophobe ratio of about
10.9:1 and its viscosity, under the same conditions as
previously mentioned, is about 255 centistokes. The higher
the molecular weight of the polymer the lowex ~he hydrophile:
hydrophobe molar ratio may be therein and still result in
satisfactory soil release promotion by the invented detergent
compositions. The QCJ and QCF polymers have melting points
~by differential thermal analysis) of about 50 to 60~C.(but
minor proportions of such products will remain ln solid state
at temperatures up to 100C.),a carboxyl analysis of 5 to 30
equivalents/106 grams and a pH of 6 to 8 in distilled water
at 5~ concentration. The molecular weights (weight average)
are in the range of 20,000 to 25,000 and the ethylene tere-
phthalate:polyoxyethylene terephthalate units molar ratio is
d ~: 3~7~
about 74:26. All three of the mentioned trademarked products
are water soluble or substantially water soluble in warm or
hot water ~at 40 to 70C.) or at least are readily dispersible,
and may be characterized as of high molecular weight, over
5 15,000, generally in the range o 19,000 to 43,000, often pre-
ferably 19,000 to 25,000, e.g., about 22,000. In the present
application when proportions of the soil release polymer are
given such are on the basis of the polymer, including any in-
solubles therein (which can be less active as soil release
agents). Ideally, the release polymer employed will be 100%
water soluble.
Normally, for "~olution" application to materials
or for solution addition to a detergent composition in wash
water, the copolymers of this invention may be employed in
aqueous dispersion. In such dispersions a surface active
agent may be present to assist in maintaining the dispersion
uniform. Only small proportions of such surface active
agent will be employed, if any. Normally, the concentration
of the polymer in the aqueous medium will be about 5 to 25%,
on a composition basis, preferably 10 to 20%, e.g., 16%, and
such is the concentration at which the mentioned commercial
products are normally supplied when a liquid form is desired.
While li~uid dispersions or solvent solutions of the polymer
may be employed for direct additions of the pol~mer to the
medium in which the fabrics are to be treated, when the
polymer is to be incorporated in a particulate detergent
composition it will be preferable for it to be in solid
form, preferably as an anhydrous particulate solid of a
particle size like that of the other detergent composition
- 13 -
components. Alternatively, it may be finely divided and
powdered onto spray dried beads of the other components. In
more pref~rred methcds of incorporation in a detergent
composition the polymer may be dissolved in nonionic detergent
and sprayed onto base beads or may ~e prilled with-carriers
and mixed with the base beads. It has been found that the
polvmer should not be added to an aqueous crutcher mix
containing anionic detergent and/or builder salt and it
should not be brought into contact with water soluble
- 10 builder salt in the presence of moisture, especially at an
elevated temperature. Accordingly, to make free flowing
particulate product, normally the polymer will be essentially
dry or very low in moisture content. The use of such a
product also allows for the manufacture of base beads at
normal moisture content without the moisture content thereof
being increased objectionably by post-spraying of an aqueous
dispersion of the polymer onto the beads.
The PVP employed has been found effective in
stabilizing the described soil releasing polymers in the
presence of alkaline builder, and is especially effective in
the presence of sodium tripolyphosphate, which may be accompanied
by sodium silicate. Such PVP usually has a molecular weight
in the range of about 5,000 to 200,000, preferably 10,000 to
160,000 and most preferably about 10,000 to 50~000O However,
in some cases PVP with a molecular weight greater than
'7~
200,000 has been found useful, although not as effective as
the compounds within the ranges given. Thus, PVP with a
molecular weight of about 360,000 exhibits some stabilizing
effect but normally will be uneconomic in view o~ the superior
results obtained with the lower molecular weight products.
A preferred source of PVP i5 GAF Corporation, New York, N.Y.,
ana the preferred commercial products of that company are
marketed under the designations K-15 (M.W. = lO,000), K-30
(M.W. = 40,000) and K-60 (M.W. - 160,000)~ Their K-90 product
: 10 has a molecular weight of about 360,000. All the described
products are water ~oluble and additionally, are soluble in
molten nonionic de~ergent of the type preferably employed in
accordance with this invention (a condensation product of a
higher fatty alcohol with ethylene oxide). While PVP is
highly preferred it is considered that other polylactams, such
as polyvinyl oxazolidinone, may also be useful in at least
partial replacement of the PVP. Polyacrylamide and related
amides possess some stabilizing properties too, but they are
inferior to PVP in this respect.
Various suitable adjuvants may be present in the
invented detergent compositions, such as enzyme powder, which
helps to decompose stains and other soils so as to promote their
removal, ~hereby coacting with the soil release aiding polymer;
perfumes; fluorescent brighteners; colorants (dyes and water
74
dispersible pigments, such as ultramarine blue3; bactericides;
fungicides; and flow promoting agents. Some of these materials
may be added in the crutcher so that they are parts of the
base beads, and some of them will be pos~-added. Inorganic
fillers, such as sodium sulfate and sodium chloride, may be
utilized but prefera~ly the proportions thereof will be
limited, one reason for this being because it has been found
that sodium sulfate tends to react adversely with the
present polymers. Of the enzymes, both prsteolytic and
amylolytic enzymes may be employed, such as those sold under
the tradenames Alcalase, manufactured by Novo Industri, A/S,
and Maxazyme, both of which are alkaline proteases (subtilisin).
In the invented detergent compositions the proportion
of synthetic organic nonionic detergent will be from about 5
to 30%, preferably 10 to 25% and more preferably 15 or 18 to
22%, e.g., about 20 or 21%. The to~al proportion of water
soluble alkaline builder will be from about 30 to 80%,
preferably from 40 to 75%, and more preferably 45 to 70~.
When the builders are sodium tripolyphosphate and sodium
silicate, as is preferred, the proportions thereof are
preferably about 30 to 70% and 3 to 15%, respectively, more
preferably 40 to 65% and 5 to 13%, e.g., 54% and 10%. The
proportion of soil release promoting polymer will be from
about 0.5 to 20%, preferably 1 to 10%, more preferably 1 to
5~ and most preferably 2 to 5%, e.g., 3%. The moisture
- 16 -
content of the product will usually be from 1 to 20%,
preferably 3 to 15% and more preferably 5 to 12%, e.g., 9%.
Individual adjuvants preferably constitute no more than 10~
of the composition, more preferably being limited to 5% and
often to 2 or 3%, with the total of adjuvants desirably not
exceeding 25%, preferably being limited to 1~% and more
preferably being held ~o 5 or 10~ of the composition. Of
course, mixtures of individual components of the invented
compositions and of adjuvants for them may often be desirably
employed, and such are intended to be included when a single
type of component is mentioned. Enzyme powder, when present,
will usually be at a concentration in the range of 0.5 to
3~, preferably 1 to 2~. Such enzyme powder is commercially
available as a mixture of active enzyme and carrier material,
e.g., Maxazyme 375.
The detergent composi~ions, whether previously
manufactured and stored before use, or made immediately
prior to use, may be employed in dilute aqueous solution (or
dispersion) in wash water to wash all~synthetic mate~ials,
including polyesters; cotton-synthetic blends, including
cotton-polyester blends; cotton~; nylons; and mixtures of
such materials. Normally the dry weight of materials being
washed will be from 2 to 15 or 20~ of the weight of the
aqueous washing medium, and preferably S to 10% thereof.
The wash will be conducted with agitation over a period from
5 minutes to 1/2 hour or one hour, often from 10 to 20
minutes, and after washing the materials will be rinsed,
usually with several rinses, and will be dried, as in an
automatic laundry dryer~ The wa~h water will usually be at
a temperature of 10 to 95~C., preferably 15 to 60C. or 20
to 50C., and more preferably 40 to 50C., and the concen-
tration of the detergent composition or the equivalent
components (if separately added to the wash water) will be
from 0.05 to 1%, preferably from O.P5 to 0.15%, e.g., 0.06%
or 0.13%. The detergent compositions have a bulk density in
the range of 0.2 or 0.4 to 0O9 g./cc., preferably 0.6 to 0.9
g./cc., e.g., 0.65 g./cc. and such detergents of such prefer-
red bulk density are normally employed at a concentration of
about 1/4 cup (or about 40 grams) per wash, with the wash
tub usualiy containing about 17 gallons (U.S.~ of water for
top loading machines and about 7 to 8 gallons for front
loaders. When a "~uropean" type of washing machine is
employed, wherein higher concentrations of detergent composi-
tion are utilized, with lesser amounts of water, and which
machines usually operate at higher washing temperatures, it
may be preferable to lower the washing temperature for best
depositing of the polymer on the washed materials. The upper
portion of the broad range of de~ergent composition concen-
trations previously given may be considered as appropriate
for European washing conditions whereas the corresponding
- 18 -
L3~
intermediate and lower parts are for "American" type front
loading and top loading washers and washing conditions, often
with the concentration for the front loading m~chines being
lower than that for the top loaders.
The proportions of the individual activè eomponents
of the present compositions in the wash water will normally
be from 0.001 to 0.14~ of nonionic detergent, 0.006 to 0.40
of builder, 0.0001 to 0.10~ of soil releasing agent and
0.00002 to 0.5~ of PVP. Preferably such proportions will be
from 0.003 to 0.02%, ~.02 to 0.05%, 0.0003 to 0.01%, and
O.00006 to 0.006%, respectively. When sodium tripolyphosphate
and sodium silicate are present in the wash water the normal
percentages of the significant components of the present
compositions that will be in the wash water are 0.0006 to
0.040% of nonionic detergent, 0.017 to 0.12~ of sodium
tripolyphosphate, 0.002 to 0.023~ of sodium silicate, 0.0008
to 0.009% of soil releasing polymer and 0.00013 to 0.004% of
PVP, with more preferred ranges being 0.009 to 0.013~, 0.024
to 0.039~, 0.003 to 0.008%, 0.001 to 0.003~, and 0.0002 to
0.0012~, respectively.
The base beads which may be employed in making the
compositions of ~he invention are preferably spray dried
from an aqueous crutcher mix which normally will contain
from about 40 to about 70 or 75~ of solids, preferably 50 to
65~ thereof, with the balance being water, preferably
deionized water, as previously described (but city water may
-- 19 --
also be employed). The crutcher mix i5 preferably made by
sequentially adding various components thereof in a manner
which will result in the most miscible, readi~y pumpable and
non-setting slurry for spray drying~ The order of addition
of the materials may be varied, dependiny on the ~ircum-
stances, butitis most desirable when "settable" cru~cher
mixes are employed to add the silicate solution (if any)
last, and if not last, at least after the addition of any
gel- or "freeze"-preventing combination of materials or
processing aids, such as citric acid and magnesium sulfate.
Normally it is preferable for all or almost all of the water
to be added to the crutcher first, preferably at about the
processing temperature, after which the processing aids (if
present) and other stable minor components, including pig-
ment and fluorescent brightener, if present, are added,ollowed by most of the builder~s), including phosphate
builder, and silicate builder. Usually during such additions
each component will be mixed in thoroughly before addition
of the next component but methods of addition may be varied,
depending on $he circumstances, so as to allow co-additions
when such are feasible. Sometimes component additions may
be in two or more par~s and sometimes different components
may be pre-mixed before addition, to speed the mixing
process. Normally, mixing speed and power will be increased
as the materials are added.
- 20 -
3~
The temperature of thè aqueous medium in the
crutcher will usually be about room temperature or elevated,
normally being in the 20 to 80C. range, preferably from 30
to 75 or 80C., and more preferably 40 to 70 or 80~C.
~eating the crutcher mediwm may promote solution of the
water soluble salts of the mix and thereby increas~ miscibility
but the heating operation, when effected in the crutcher,
can slow production rates. Temperatures higher than 80C.
(and sometimes those higher than 70C.) will often be
avoided because of ~he possibility of decomposition of one
or more of possible crutcher mix components, e.g~, ~odium
bicarbonateO Also, in some cases lower crutcher temperatures
increase the upper limits of crutcher solids contents,
probably due to insolubilizing of normally gelling or setting
components. Such problems are not usually encountered when
the main builder present is a polyphosphate.
Crutcher mixing timeq to ob~ain good slurries
can vary widely, from as little as five minutes in small
crutchers and for slurries of higher moisture content5, to
as much as four hours. The mixing times needed to bring all
the crutcher mix components substantially homogeneously
together in one medium may be as little as ten minutes but
in some cases can take up to an hour, although 30 minutes is
a preferable upper limit. Co~nting any such initial admixing
times, normally crutching periods will be from 15 minutes to
3~7~
two hours, e.g., 20 minutes to one hour, but the crutcher
mix should be such ~s to be mobile, not gelled or set, for
at least one hour, preferably for two hours, and more prefer-
ably for four hours or longer after completion of the making
of the mix. ~he present mixes are stable for at ~east four
hours. They do not set during that time when polyphosphate
is the main builder, and when carbonate-silicate mixtures
are employed an anti-setting agent, such as citric acid plus
magnesium sulfate, will be present to delay setting.
The crutchea ~lurry, with the builder salt(s) and
other components thereof dissolved or in particulate orm
and uniformly distributed therein, is transferred in usual
manner to a spray drying tower, which is normally located
near the crutcher. The slurry is dropped from the bottom of
the crutcher to a positive displacement pump, which orces
it at high pressure through spray nozzles at the top of a
conventional spray tower (countercurrent or concurrent)
wherein the droplets of the slurry fall through a hot drying
gas, usually the combustion products of fuel oil or natural
gas, in which the droplets are dried to desired bead form.
During drying absorptive beads are made, which are especially
useful to absorb liquid state heated nonionic detergent~
which may be post-sprayed onto them subsequently.
After drying,the product is screened to desired
size, e.g., 10 to 60 or 100, U.S. Sieve Series, and is ready
for application of nonionic detergent spray thereto.
- ~2 -
lL3~7~
Although the foregoing description is of the making of
spray dried inorganic builder salt base heads, and such are
preferred for various reasons already men~ioned, ~uch as
desirable bulk density, uniformity, flowability, strength
and sorption properties, it is within the invention to
employ other equivalent or nearly ~quivalent base beads,
such as those which are agglomerates, mixes, granulates,
grinds, prills or chopped filamentsO The nonionic detergent
will usually be at an elevated temperature, such as 40 to
90~C., preferably 50 to 80C., e.g., 55C., to assure that
it will be liquid; yet, upon cooling to room temperature it
will desirably be solid, often resembling a waxy solid.
Even if at room temperature the nonionic detergent is
slightly tacky, this characteristic does not necessarily
make the final composition poorly flowing because the
detergent penetrates to below the bead surface (to within the
bead). However, waxy detergents are preferred. The nonionic
detergent is applied to the moving or tumbling base beads in
known manner, as a spray or as droplets. The enzyme preparation
(herein referred to as enz~me, although it is recognized
that it includes a carrier ma~erial, too), soil releasing
polymer, PVP and any other powdered adjuvants may be dusted
onto or mixed with the builder base particles, and perfume
and any other liquids to be post-added may be sprayed on at
~5 a suitable point before or after addition(s) of the powder(s).
- 23
7~
The nonionic detergent may be sprayed onto absorbent
base builder beads and the soil release promoting polymer
and PVP may be post-added together, with the soil release poly-
mer being stabilized by the PVP against the d~grading action
of the alkaline builder base beads. Such stabili~ing effect
of the PVP is obtained when the release promo~ing polymer
and the PVP are in contact, preferably when contact of the
xelease polymer and the alkaline builder is also prevented
or diminished. However, two particular ways of incorporating
- 10 the nonionic detergent, soil release polymer and PVP in the
product are highly effective and are preferred. The more
preferred method is by spray drying an aqueous crutcher mix
of the alkaline builder salt to produce dried absorbent
particles, dissolving the formula proportions of soil releasing
pol~mer and PVP in nonionic detergent in liquid state, and
spraying or otherwise effec~ively distributing the nonionic
detergent solution of the release polymer and PVP onto the
surfaces of the alkaline builder beads. In carrying out
such a procedure it is highly desirable that the nonionic
detergent be substantially or essentially anhydrous, normally
containing less than 1%, preferably less than 0.5% and more
preferably less than 0.2% of moisture. It is preferred that
the nonionic detergent be at a temperature in the range
of 40 to 90C., more preferably 50 ~o 80~C., at which the
- 24 -
3~
normally solid and waxy detergent will be molten and at
which temperature the soil release promoting polymer and the
PVP will dissolve in it (in the formula proportions). Also,
the base beads will preferably be warmed and are kept in motion,
as in a sui able mixer, such a a rotating longitudinal drum
or tube which is inclined slightly, e.g., 5 to 10 from the
horizontal. The spray droplets will preferably be of a size
delivered from a typical spray gun, usually being of a
diameter in the range of about 0.1 to 1 mm. The mentioned
spraying and mixing can be effected in times as short as one
or two minutes but normally from 5 to 10 minutes may be
desirable. Surprisingly, although the spraying of the
li~uefied nonionic detergent onto the base beads brings the
soil release polymer into close contact with such beads and
the alkaline bullder salts of which they are composed,
apparently due to the presence of the PVP the soil release
promoting polymer remains stable on storage, even at somewhat
elevated temperatures~ Comparisons with other soil release
detergent compositions of similar formulas but without the
PVP show that the experimental formulas are far superior in
lasting soil release promoting characteristlcs.
Another preferred method for making a detergent
composition of this invention includes dissolving the PVP in
a li~uid medium, such as water, suitable alcohol, e.g.,
methanol, or suitable volatile chlorinated organic solvent,
25 -
L3~
such as methylene chloride. Desirable concentrations of the
PVP in the solvent will normally be within the range of 5 to
25%, with higher concentrations preferred when ~olvent
removal is more of a problem, as when water is being used.
The solvent solution of PVP is then applied to particulate
soil release promoting polymex, with the rate of application
being such as to apply the de~ired formula proportion of PVP
to the soil release agent. Thus, for example, when it is
desired that the final detergent composition contain 3% of
release polymer and 0.5~ of PVP, enough PVP solution will be
sprayed or otherwise applied to the surfaces of the particles
of the release polymer to produce an intermediate product
containing about 86~ of release polymer and about 14% of
PVP. Th~ particle sizes of the release polymer will preferably
be within the same range as the desired sizes of the nonionic
detergent-builder particles of the final detergent composition
but other sizes of particles may also be employed, although
they will not be as advantageous and may separate out to
some extent from the detergent-builder particles. Such detergent-
builder particles will be made by spraying the formulapropor~ion of molten nonionic de~ergent onto the absorbent
builder salt base beads in a manner like that previously
described. Nex~ the two types of particles are blended
together and the formula is ready for use. The detergent
composition resulting is one in which the release promoting
- 26 -
polymer is protected by the PVP from the degrading action of
the alkaline builder salt. Additionally, the presence of
the nonionic detergent on the builder salt, covering substan-
tial portions of the surfaces thereof, further helps to
prevent detrimental interactions.
In the applications of PVP to the base beads (with
nonionic detergent and release pol~mer) and to the release
polymer particles the PVP protects the release polymer from
the alkaline builder and furthermore, improves the product
otherwise. PVP possesses useful anti-redeposition properties
and has been observed to promote stain removal from laundry.
In the present compositions i~ aids in soil release,
especially at room temperatures or thereabout, to an extent
which is greater than that attributable to stabilization of
; 15 the soil release promoting polymer. A coating of the PVP
helps to protect the detergent composition against the effects
of atmospheric moisture~ Yet, PVP is readily soluble in the
wash water, leading to quick dissolving and dispersion of the
detergent components. Although many o~her products have ~.
been tested, none has been found to give the very desirable
effects of PVP, not even other water soluble polymeric amides.
The following examples illustrate the invention
but do not limit it. Unless otherwise indicated, all parts
are by weight and all temperatures are in C.
3~
EXAMPLE 1
Percent
Pentasodium tripolyphosphate 54.3
Neodol 23-6.5 (condensation product of 20.7
approximately 6.5 moles of ethylene oxide
and a higher fatty alcohol averaging between
12 and 13 carbon atoms per mole)
Sodium silicate (Na2O:SiO2 - 1:2.4) 9.58
Moisture 9-05
10 Soil release promoting polymer (a copolymer of 3.00
polyethylene terephthalate and polyoxyethylene
terephthlate of a molecular weigh~ of about
22,000 wherein the polyoxye~hylene is of a
molecular weight of about 3,400, the molar ratio
of polyethylene terephthlate to polyoxyethylene
terephthlate units is about 3:1 and the propor-
tion of ethylene oxide to phthalic moie~y in the
polymer is about 22:1, sold by Alkaril Chemicals,
Inc. as Alkaril QCF)
20 Proteolytic enzyme (Maxazyme) 1.32
Fluorescent brightener (Tinopal 5BM) 1.26
Polyvinyl pyrrolidone (GAF Corporation K-15 PVP 0.50
having a molecular weight of about 10,000)
Perfume 0.20
25 Dye (Blue, Mix No. 5) 0.05
Dye (Polar Brilliant Blue) 0.04
100. 00
A particulate built nonionic synthetic organic
detergent composition of the above formula, which is useful
for washing synthetic organic polymeric fibrous materials,
such as those of polyesters and polyester-cotton blends, and
imparting soil release propertiPs to them, is made by the
- 28 -
~l2~3~7~
following method. First, base beads of the tripolyphosphate
and silicate are made by dispersing the tripolyphosphate, as
a finely divided powder, in water and adding to it the
formula proportion t9.58~) of anhydrous sillcate as a 47.5
S solids solution, with the solids concentration of the
crutcher mix made being about 55~. The water employed is
deionized but sometimes city water will be substituted,
providing that its hardness is less than 300 p.p.m. as
calcium carbonate. Preferably, fluorescent brightener and
any colorants, such as th~ blue dyes, which are sufficiently~
crutcher stable, are added to the crutcher, too. The crutcher
mix is maintained at a temperature in the range of about 60
to 70C. and mixing is continuous. The mixing, including
addition and dropping, which are both conducted while mixing,
normally takes about 20 minutes to an hour but may be under-
taken for longer periods, up to four hours or more, because
the phosphate-silicate-dye-brightener dispersion-solution
does not tend to set in the crutcher.
After sufficient mixing to obtain a substantially
uniform slurry, in which the fluorescent brightener and dyes
will often preferably be present, during which time some
moisture may be lost by evaporation, and may be replenished,
if desired, the mix is dropped from the crutcher to a pump,
which pumps it at a pressure of about 21 kg./s~. cm. into
the top of a countercurrent spray tower wherein the initial
- 29 -
~2~4374
drying temperature i5 about 430C. and the inal air tempera-
ture is about 105C. The base beads resulting are of a bulk
density of about 0.5 g./cc. when cooled after manufacture, and
are of paxticle sizes in the range of No's. 10 to 100, U.S.
Sieve Series. They may be screened to such range or to a
particulate product having fewer smaller particles, ~.g.,
10 to 60 sieve. The moisture content of the product is
about 12.1%. The base beads are free flowing (generally
with about an 80~ flow rate), non-tacky, satisfactorily
porous, yet firm on the surfaces thereof and are capable of
readily absorbing significant proportions of liquid nonionic
detergent ~and dissolved QCF and PVP) without becoming
objectionably tacky.
After cooling of the spray dried base beads they
are screened so that substantially all (over 95~ and often
over 98%) are within the range of No's. 10 to 100 sieve,
U.S. Sieve Series, and are sprayed with a solution of QCF
and PVP in anhydrous nonionic detergent, in final product
formula proportions. Thus, 0.5 part of the PVP and 3 parts
~f the QCF are dissolved in 20.7 parts of Neodol 23-6.5,
which is essentially anhydrous and which is at a temperature
of about 71C. and is sprayed onto tumbling base builder
bead surfaces, preferably while the beads are being mixed in
a tumbling drum, which may be a longitudinal drum or tube
inclined to the horizontal at about 8. The spray dr~plets
- 30 -
37~
are largely of particle sizes in the 0.1 to 1 m~. range and
the spraying operation will be such as to result in a
throughput time in the sprayer-mixer of about 10 to 20
minutes, with the enzyme and perfume being applied in the
5 mixer after the nonionic detergent containing PVP.and QCF.
The resulting detergent composition particlPs, when ~ooled,
are of a bulk density of about 0.65 g./cc. The product
is attractive and regular in appearance, and is free flowing
and non-dusting.
The detergent compositions described above are
excellent heavy duty laundry detergents and are especially
useful for washing household laundry in automatic washing
machines and at the same time imparting soil release character-
istics to them. When employed at a temperature of about 45
to 50C. and a concentration of about 0.05 to 0.15~, e.g.,
0.06~, in a 17 gallon capacity washer, in the washing of
normal loads of 100% polyester and 65% polyester - 35%
cotton fabrics in home laundry or commercial washing machines,
whether of the top loading or front loading types, or at
higher temperatures and concentrations in European type
washing machines, the compositions perform satisfactorily,
as would be expected from a knowledge of their components,
with respect to usual washing effect characteristics,but
additionally they significantly promote soil release from
such materials. They are also satisfactory for washing
3~7~
nylons, cottons, acetates and blends of fibrous materials
and they promote soil release from such materials too,
although not to the same yreat extent as with the poly-
esters. In tests of the washing and soil release actions of
the compositions a General Electric Company top lQading washing
machine or a Terg O-Tometer test washer is used, the water tem-
perat~re is about 45~C. and the water contains a total of about
200 p.p.m. hardness as CaC03, of mixed calcium and magnesium ions.
The washing test times are all about ten to fifteen minutes
and the laundry : water ratio is about 1:20, by weight.
Items are rinsed twice automatically and then are dried in
an automatic laundry dryer or other suitable drying means.
The presence of the PVP with the present soil
release promoting polymer significantly stabilizes the
release polymer so that with the human eye and by reflecto-
meter readings it is evident that be~ter soil release on
washing results when a detergent composition comprising the
release polymer and PVP is stored for 2 to 4 weeks at
elevated temperature and is then used to treat polyesters
and polyester-cotton blends, compared to the same product
from which the PVP was omitted (not incorporated in the
nonionic detergent with QCF) but which was stored and used
in the same manner. For better stabilization of the polyester
soil release promoter the ratio of PVP to soil release agent
should be within the range of 1:15 to 1:2 or 1:1, preferably
~ 32 -
3~
1:10 to 1:3, e.g., 1:5 or 1:6. The soil release promoting
effect is more significant on repeated launderings, usually
up to five launderings of the washed materials, with the pre-
sent compositions (or with equivalent wash water ~olutions).
In addition to users of the present pro*~cts noting
the in,proved soil release in washing n~rmal loads of laundry
containing articles soiled with oils or greases, comparative
tests wherein dirty motor oil is applied to swatches sf poly-
ester and polyester~cotton blend materials after such swatches
have been washed in either the invented compositions or ~ontrol
compositions (which are the same as those of the invention but
without PVP) show improved soil release promoting for the
invented produc~s when both such and the control have been
stored at elevated temperatures, e.g , four weeks at 45C.
before being used to wash-treat the swatches. In such tests
skilled observers note the improvement in soil removal by
washing with a composition of the invention or a control,
respectively, after fixst treating and then oil soiling, and
such conclusions are confirmed by reflectometer checks of
the washed materials. Similar results are obtained when the
polyester test materials are washed with the experimental and
control detergents, are soiled with dirty motor oil and are
then washèd with a commercial detergent, such as a phosphate
built anionic detergent of the FAB type.
When variations of the above formulas are made,
changing the proportions of soil release polymer and PVP
- 33 -
3~
plus or minus 20% and plus or minus 50%, similar results are
obtainable but with the greater proportions of PVP (and
release polymer) the soil release effects are better after
storage, due to improved stability of the QCF. Similarly,
when such changes are made in the builder, nonion~c detergent
(to Neodols 25-7 and 23-3) and enzyme components, keeping
the formulas within the ranges previously given, useful
products result, of improved soil release characteristics
despite storage, providing PVP is present. Also, when the
PVP is changed to K-30 or K-60 excellent stabilizing of the
QCF results, but with K-90 the stability is less. The
described results are also obtainable when other polyethylene
terephthalate-polyoxyethylene terephthalate copolymers are
employed provided that the molecular weights and ratios are
within the ranges recited in the specification.
EXAMPLE 2
When the compositions of Example l are made by
spray drying the base beads, having them absorb a spray of -~
heated nonionic detergent (at 55C.), coating QCF particles
in the 10 to 100 sieve range with PVP (K-15? ~o produce
particles still in that range, and blending the two partic-
ulate intermediate compositions, in the appropriate propor-
tions,a stabilized soil release promoting detergent results.
The PVP solution used is at a concentration of about 15~ in
methanol, water or methylene chloride, and i~ is applied so
- 3~ -
~2~37~
as to deposit the formula proportion of PVP on the QCF.
Instead of using an inclined drum mixer a fluid bed dryer
(Aeromatic Co.) is employed or the coating of the QCF
particles with PVP, and for evaporation of the solYent.
Although the described coating method is useful
and the products resulting are of bulk dencity, detergency and
soil release promoting characteristics for lipophilic soils
that are comparable to those of the products of Example 1,
and are of other good physical characteristics like those
of Example 1, it is preferred to employ the absorption
method described in Example 1 because it does not require
any extra equipment or any additional process steps other
than a mixing tank for the dissolving of the QCF and PVP in
the nonionic detergent. Also, solvent recovery means are
not needed and water evaporation does not have to be effected.
EXAMPLE 3
Results like those given in Examples 1 and 2 are
also obtainable by use of other compositions, the components
of which may be separately added to the wash water at the
normal washing temperaturas and concentrations given. While
it is preferred to utilize the compositions described,
containing nonionic detergent, alkaline builder salt, soil
release imparting polyester and PVP or other suitable poly-
lactam or polyamide, because the components thereof are in
desired proportions and are ready to use, additions sf
different partial mixtures of components or individual
- 35 -
7~
components may be made to the wash water, and excellent soil
release characteris ics will be acquired by the polyesters
and polyester-cotton blend materials being washed (and
treated). Of course, when the QCF or similar soil release
agent is separate from alkaline builder salt therç will be
~ittle or no need to stabilize the release agent, Still,
even in such cases excellent imparting of soil release
characteristics is obtainable, employing the same washing
conditions as previously mentioned in Examples 1 and 2, and
the PVP contributes stain removal and æoil dispersion
properties which further help to improve the washing character-
istics of the detergent composition solution.
Instead of employing particulate detergent composi-
tions, liquids may be utilized, such as more concentra~ed
aqueous solutions, such as those of 5 to 25 parts solids,
in water or in water and alcholic solvent, and these are
especially useful for pre treating before washing any portions
of clothing items that are likely to be most soiled by oily
materials. Such use is to prevent subsequent hard-to-remove
soiling and is particularly appropriate for shirt ~ollars
and cuffs, work gloves and aprons, for exampleO The presence
of the PVP is considered to help stabilize such liquid
preparations but if they are made shortly before intended
use such stabilization may not be necessary.
Many variations of the above formulas can be made,
utilizing other nonionic detergents, other builders and
- 36 -
~ 3t~
builder combinations, other soil release promoting polymers
and other types of PVP, such as have been described in the
specification. Also, the various proportions may be changed
wi~hin the ranges given, and useful effects of the desired
types will result. lt is surprising that the pre~ent composi-
tions are so effecti~e and of acceptable and practical
stability despite storage at elevated temperatures because
PVP is extremely water soluble and would not be expected to
"insulate" the soil release agent from atmospheric moisture,
which, in the presence of water soluble alkaline salt, would
be expected to cause degradation of the release agent.
Also, when nonionic detergent containing dissolved release
agent is deposited on base beads of alkaline builder salt it
would be expected that the bringing into intimate contact of
the alkaline material and the QCF (or QCJ) would promote
degradation of the release agent, even in the presence of
PVP. Such does not happen, as has been reported above.
Yet, because of the water solubility of the nonionic detergent
and its hydrophilicity it would not be expected that it ``
would restrict contact of the alkaline builder salt and the
soil release promoter. In short, the present in~ention, in
which PVP stabilizes polyester soil release promoting
material against alkaline hydrolysis and degradation is
unexpected and xepresents an important advance in the
detergent axt.
- 37 -
~2~37~
The invention has been described with respect to
various examples and illustrations thereof but is not to be
considered as limited to these because one of ~kill in the
art, with the present specification before him, will be able
to utilize substitutes and equivalents without departing
from the invention.
- 38 -
