Note: Descriptions are shown in the official language in which they were submitted.
~C~733~)~
This invention relates to amphoteric surfactants, and more
particularly to specific ethyoxylated amines which are quaterni~ed and at
least partially phosphated: methods of making such surfactants; and to
methods of using such surfactants. ~ore particularly, this invention relates
to a method comprising treating a metal surface with an aqueous cornposition
! ~ containing an effective cleaning, lubricating, rustproofing ~*~for corrosion
proofing amount of an amphoteric surface active agent of the formula:
R \ ~CH2CHO)n 1 X
Rl (CH CHO~ - 2
wherein R is C6 22 alkyl or alkenyl, Rl is lower alkyl or benzyl~ R2 and R3
each represent H or CH3, n is an integer of 1-50, Zl is with the bonded O
atom, a phosphate ester group in acidic or salt form, Z2 is H or Zl~ X is an
anion.
Such active agents can be made through reaction (phosphating) of
such dihydroxy quaternary compound with a conventional phosphating agent such as
P205~ polyphosphoric acid, or POC13 to form amphoteric surface active agents
having utility as metal lubricants, heavy duty cleaners, and detergents.
The above active agent may be compounded with other conventional
cleaning agents. For example, the composition may contain from about 2 to
about 17% by weight of caustic soda, or up to about 10% by weight of tetra-
potassium pyrophosphate (TKPP) or a mixture thereof.
In particular, the ultimate complex phosphate ester surfactants
themselves, that are derived from phosphating in the manner discussed above,
are compositions which are characteri~ed by the following chemical formula
or structure
~33~
R2
\ ~ ~ (cH2cHo)n 1 X
R / ~ (CH2CIHO)n - Z2
R3
wherein R is C6 22 alkyl or alkenyl, Rl is lower alkyl or benzyl, R2 and R3
each represent H or C113, n is an integer of 1-50, Zl is with the bonded O
ato~, a phosphate ester group in acidic or salt form, Z2 is H or Zl and X
is an anion such as,
~i ~, - 2 -
~6~73~
e g., halogen, sulfate, or alkyl sulfate. Of course, as
would be appreciated by those skilled in the art, the
diesters and triesters of the above formula can exist in a
variety of forms, e.g., in the form of a variety of
aliphatic3 cyclic, and polymeric compounds. However, in
accordance with the presen~ invention, the major products
formed comprise aliphatic monoesters and diesters.
The prior art describes many, and varied, types
of amine phosphonates, phosphates, and related compounds.
For example, various hydroxy alkyl and dihydroxyL alkyl
derivatives of higher fatty acid amines have been phosphated,
but none of these compounds have achieved significant commer-
cial acceptance and in none have been found all of the '
desirable properties of the instant invention.
Considerable research has been carried out during
the past few years directed towards improving the lubricating
and rust and corrosive inhibiting properties of the new
synthetic surfactant compositions. Most of the~e
surfactant compositions have, as active surfactant
ingredient, anionic ions. As representative of the
various additives which have been employed for improving
the detersive and surfactant properties of such anionic
compositions, there may be mentioned alkali metal
phosphates, borates, carbonates, sulfates, chlorides,
silicates, higher aliphatic alcohols such as lauryl
alcohol, and higher fatty ~cid amides and alkylol amides
such as lauroyl amide, lauroyl mono and dialkyl amides,
~733~
l~uroyl ethanolamide, ~nd lauroyl di-ethanolamide. The use
of the aforementioned alkali metal salts, par~icularly the
phosphates and borates, genera]ly have resulted in what is
known as "built" or "heavy duty" type detergents. While
such compositions are partially suitable for use in cleaning
machines of various types, ~hey find limi~ed used in appli-
cations wherein any degree of metal lubrication and
cleaning is involved. H~wever, these additives, which have ~^
thus far been more or less commercially accepted, have
] properties and characteristics which still leave much to be
desired with respect to preEerred or favored characteristics
such as more universal compatibility and adaptal)ility to
different conditions, costs and the like.
Various organic surfactants have achi~v~d
considerable commercial success; however, the art is still
confronted by the problem of providing surfactant composi-
tions which provide dual cationic and anionic functionalities
and yet are free from undesirable disadvantages.
It has been found that the compositions according
to the instant invention comprise very valuable surface-
active agents which may be used either alone or admixed with
other cat~onic, anionic or non-ionic surface active agents
in the different fields as above referred to.
The instant compositions comprise a very valuable
group of surface-active agents, known as amphoteric compounds 9
i.e., chemical agents containing both cationic and anionic
groups in a single molecule, and therefore exhibit a h~gh
degree of st.ability and renarkable utility in concentrated
electrolytic solutions. These compounds also show unusual
--4--
~33~3~
chemical stability under prolonged contact with alkaline
systems. Products made from the instant compounds have the
following advantages: they possess good surface-active
properties so that they can be used as detergents (since
they have the advantage of preventing the accumulation of
electrostatic charges); are well tolerated by ~he skin and,
therefore, do not cause any appreciable irritation thereto;
are useful as lubricants, rust inhibitors, corrosion
inhibitors, hard surface cleaners, alkali soluble cleaners,
agricultural emulsi:Eiers, hydraulic fluids, and in emulsion
polymerization.
These amphoterics employ the phosphate ester as
the anionic moiety, thereby in addition to providing dual
cationic/anionic functionality, offer novel properties such
as metal lubrication, and cleaning, enhanced corrosion
inhibition, and alkali solubility.
The compo~mds of this invention have the following
unexpected combinations of properties: (1) they, unlike
phosphates of ethoxylated amines, tolerate the presence of
chlorine bleaches; (2) they may be used in shampoos and
other cosmetics at pH values of 4.5-8.5, and, under these
conditions, are effective cleaning agents, whereas
conventional counterparts to these materials do not work
well under pH values of 6.0: e.g., conventional amphoterics
such as betaines do not work at their isoelectric point
(about pH 5.7) since they become insoluble at these pH
~733~
values; ~3) t~e~ are better detergents with sverage or hard
water; do not precipitate;and at pHs as low as 4.5, are
mild to the eyes and skin and are relatively non-toxic.
In addition, these products are readil~y biodegradable, and
as such are ecologically safe. The instant amphoteric -~
eompounds are useful as detergents, weltting, emulgating,
and emulsifying agents, and also posse~s a unique combina-
tion of properties which provide n~w and improved products
for lubricants, pesticide emulsifiers, and hard surface
cleaners. They are al80 useful as surface actlve agents in
treatin8 natural and synthetic fibers in ~he textile and
related fields where they may be employed as syn~hetic
detergents, dye assistants, and sof~eners.
These amphoteric surfactants also sh~w an advantage
over the prior art and seemingly do not exhibit a pronounced
isoelectric poin~ where general surface-active and physical
properties such as solubility and foaming are at a minimwm.
As previously noted, the present complex phosph~te
surfactants are derived from quaternary dihydroxy compounds
previously described above, and, as derived9 are obtained in
two major forms- (1) as monoesters, and (2~ as diesters, wi~h
minor amounts of triesters (essentially as an impurity)
being formed
~733~9
The phosphate ester group may be in the acidic orm or in the form
of a salt, for e~ample of the formula Y04 ~ wherein ~1 represents H or a
conventional cation such as~ Na, K, Mg, Ca, or Al, preferably Na or K, or a
suitable amine such as an alkanol amine or alkylamine, preferably mono-
ethanolamine, diethanolamine, or triethanolamine. The X moiety of the
quaternary dihydroxy compound, when a halogen, may be chlorine, fluorine,
bromine, or iodine, and preferably chlorine. When a sulfate, X can be an
alkyl sulfate, preferably ethyl sulfate. In the most pre~erred embodiment ;
R and Rl are dissimilar, one being a long alkyl chain, ~he other being a
shorter alkyl chain, the sum total of carbon atoms for R and R , taken to-
gether, not being less than 7 carbon atoms. Also disclosed are methods of
making same and uses therefor.
The compounds of the instant invention may be prepared from a
precursor material by first condensing an alkyl amine, containing 6 to 22
carbon atoms in its alkyl chain, with an alkylene oxide (e.g. ethylene oxide
or propylene oxide) in the presence of a conventional base. To produce the
quaternized component, a quaternizing agent is added thereto and the alkoxy-
lated amine is thereafter quaternized. The quaternized alkoxylated amine is
thereafter phosphated so as to produce a quaternary phosphate. The
phosphated amphoteric product is generally a mixture containing varying
amounts of monophosphate, diphosphate, triphosphate, non-phosphated nonionic
(alkoxylate), phosphoric acid, and minor amounts of other materials such
. . .
, r~ i
_ _.. A.~ 7
~733~ ~
as polymers of the foregoing phosphates.
The alkyl portion of the amine can be saturated
or unsaturated, substituted or free from substitution. A
pure source of alkyl amine to be employed can vary in
carbon length from 6 to 22 carbon atoms; examples of pure
saturated acids which can be used as precursors for such an
amine are caproic, caprylic, capric, lauric, myristic,
palmitic, stearic, arachidic, and behenic. Unsaturated
pure fatty acid precursors include those such as oleic~
lauroleic, and palmitolic. An example of a substituted
fatty acid useful in this invention is ricinoleic.
Mixtures of the above fatty acids, commonly found in
vegetable oils, animal fats and oils, and the marine fats
and oils, may also be used successfully as precursors.
Examples of vegetable sources of useful precursor fatty
acids containing mixtures in various proportions are
coconut oil, linseed oil, olive oil, palm oil, peanut oil,
tung oil, and rape seed oil. Animal and marine sources of
fatty acids containing saturated and unsaturated fatty
acid substituents are lard, tall~w, and sardine oil. Any
fatty acid or mixtures of fatty acids, whether pure or
from impure sources, may be employed as an amine precursor
without departing from the spirit o the invention so long
as they contain from 6 to 22 carbon atoms in their chain
length.
~:3i7330~
Preferred fatty acids are those contained in
coconut vegetable oil. A typical coconut vegetable oil may
contain fatty acids varying in length from 8 to 18 carbon
atoms. These fatty acids from coconut oil can be saturated
or unsaturated.
The alkyl amines used in this invention can also
be derived from the esters of the atty acids without
departing from the scope of the invention. The methyl or ~;
ethyl esters of the fatty acids can be easily condensed with
10 ~ the polyamines.~su~stituted polyamines with ready removal
of methanol or ethanol occurring.
The fatty acid amine precursor is prepared in
accordance with procedures well known in the art and~ ~ -
accordingly, that reaction and reac~ion product per se, form
no part of the instant invention.
The thus-produced alkyl amine is then subjected
to an alkoxylation reaction in accordance with procedures
well known in the art, such as, for example, by reacting
the amine with the required number of moles of ethylene
oxide to produce the ethoxylated amine employed in the
instant invention. This oxyethylatlon reaction is well ;
known in the art. The reaction is preferably carried out
at elevated temperatures and pressures, and may be catalyzed
by quaternary hydroxides, amines, acids and/or coordinating
type compounds, although strong alkaline catalyst such as
KOH or NaOH and the like are preferred because of the
fewer by-products formed and the more easily controllable
Y33~9
r
reaction conditions under which they can react. Since the
reaction is substantially quantitative, the molecular
proportions of the ethylene oxide and amine employed
determine the average oxyeth~lene chain length of the
resulting ethoxylated amine, although it will be understood
~hat the product is a mixture of ethoxylated amines of
varying oxyethylene chain length. As stated above,
sufficient ethylene oxide is employed to produce an
ethoxylated amine containing by weight about 25 to 90 percent
of combined ethylene oxide. The optimum oxyethylene chain
length wlll, in any particular instance, be determined
mainly by the particular amine being oxyethylated, the
particular detergent with which it is to be admixed, the
hardness o~ the water in which the detergent is to be
employed, the desired efficacy of the finished product for
the particular application, and the like.
Throughout the specification, the invention is
describcd with reference to the phosphated quaternized
alkoxylated amine. It is to be understood, however, that
~ the amine as well as the alkoxylated amine are products
kn~wn in the art. The alkoxylated amine may be used per se
or the amine may be alkoxylated in accordance with procedures
well known in the art.
~1~7330~
The product of the invention is then conveniently
prepared by reaoting appropria~e proportions of alkoxylated
monoalkyl amine in the presence of said hypophosphorousacld
and a quaternizing agent, such as diethysulfate~ the la~ter
being present in the amount of 50 to 100 mole %, preferably
90 to 100 mole %.
The alkoxylated monoalkyl amine starting
materials prepared by alkoxylating primary amines, have the
~2
general structure / (CH2CH0~-H
R-N
--(CH2~otH
wherein R2 and R3 are H or CH3 as above descrlbed and n is
a positive integer having an average value of from 1-50,
compounds with n-2 to 15 being preferred.
After completion of the reaction, the
alkoxylated monoalkyl amine is therea~ter submitted to
treatment conducive to quaternization of the tertiary amino
group, utilizing a conventional quaternizing agent. Thus,
noting the above structural formula, suitable quaterllizing
agents include: dialkyl sulfates, e.g. dimethyl sulfate
and diethyl sulfate; benzyl or substituted benzyl halides,
e.g. benzyl chloride, benzyl bromide, and benzyl iodide;
and alkyl halides, e.g. methyl chloride. Accordingly, any
conventional quaternizing agent can be advantageously
employed in the production of the quaternary alkoxyla~ed
monoalkyl amines used herein.
. .
~37330~
The above quaternized composition ls then
preferably but not neces~arily s~ripped of any unreacted
quaternizing agent and thereafter r~acted with a phosphating
agent so as to convert the quaternized alkoxylated monoalkyl
amine into a quaternlzed phosphate ester product. Suitable
phosphating agents include phosphorus plentoxide;
polyphosphoric acid; phosphorus oxychloride; and mixtures
thereof.
In accordance with a preferred procedure of the
present invention, the alkoxylated fatty amine and poly-
phosphoric acid are mixed together and heated to about
90-100C. under vacuum. The product thereof ls thereafter
cooled to 20 to 90C., preferably to 30C., and thereto
there is added 50 to 100 mole /O~ preferably 90 to 100 mole
%, of a quaternizing agent, and the mixture is thereafter
heated so as to effect quaternization of the alko~ylated
fatty acid amine. Any unreacted quaternizing agent m~y be
stripped away at elevated temperature and under vacuum.
The remaining product is thereafter cooled and there is
slowly added thereto the phosphating agent in am~unts of 10
to 200 mole %, preferably 90 to 110 mole %3 at temperatures
of 20 to 110C~, preferably 40 to 50~C. If phosphorus
j oxychloride~K~h~ is used as the phosphating agent, the
.~
reaction mixture is bubbled with nitrogen at such temperature
until a desired degree of chloride ion is reached,
preferably 0.01 to 1.0%. The phosphorus oxychloride
reaction product is then drowned lnto water and base and
there is thereafter obtained the surfactant solution
-12-
.... ...
~(3733~9
containing the instant product.
The nature of the invention ~y perhaps be best
understood by the detailed procedure set forth in the
examples herebelow for preparing a typical member of the
phosphated quaternized ethoxylated amphoterics; all parts,
proportions and percentages in these examples, as well as
in the appended claims, are by weight unless indicated
otherwise. Ethylene oxide throughout these examples is
referred to as "E0".
EXAMPLE I
. ~.~
Charge into a l-liter flask equipped with an
agitator, thermometer and gas inlet, 320 parts (0.5 mole)
of cocoamine + lOE0 and 2 parts of 50% hypophosphorous
acid. Dry the mixture under vacuum (10-15 mm.) at 80-100C.
Cool under dry nitrogen to 40-50C. and add 80 parts
(0 52 mole) of diethyl sulfate at 40-50C. over two hours.
Strip any unreacted diethyl sulfate at 90-100C.
under good vacuum. Cool to 30-40C., and, under a
2.0 nitrogen blanket, add 35.5 parts of phosphorus pentoxide
and stir at 100C. for 5 hours. Cool to 80-85C., add 5
parts water, and stir for 2 hours. There is obtained 433
parts of active surfactant. Thls represents a 99%
yield.
~13-
~733[)~ ~
EX~MPLE II
Operating as in Examplc I, 460 parts (0.4 mole)
of tallowamine (Armean-TD- a distilled tallow amine made
by and available from Armak3 + 20EO and 2 par~s of 50%
hypophosphorous acid are charged to a l-liter flaskO The
mixture is driPd at 90-100C. under a good vacuum, cooled
to 30-40C., and 60 parts of diethyl sulfate are added
over 2 hours. The mixture o quaternized amine ethoxylate
is phosphated in the following manner. Hypopho~phorous
acid (50%) 1 part, is added at 40-50C. followecl by 29
parts of phosphoru9 pentoxide at 50-60C. The mixture is
heated to 100C. for 5 hours under a nitrogen blanket,
cooled to 80-85C., and 5 parts water are addcd. The
system is stirred for 2 hours at 80-85C. There i8
obtained 553 par~s of 100% active surfactant
EXAMPLE III
Accord~ng to Example I, 460 parts of tallow-
amine ~ 20E0, 2 parts of 50% hypophosphorous acid, and
60 parts of diethyl sulfate are reacted to form 520 parts
of quaternized tallowamine ~ 20E0, To this mixture, 1
part 50% hypophQsphorous acid is added at 40-60Co~
followed by 170 parts of 115% polyphosphoric acid at
40-60Co under a nitrogen blanket. The phosphating mix-
ture i~ heated at 100C. for 5 hours, then cooled to
8~-85C., and 5 parts of water are added. Ater two
hours at 80-35C., 1 part of 35% hydrogen peroxide is
added to yield 697 parts of 100% active ~urfact~nt.
-14-
~73~
EX~MPLE IV
As in Example I, 586 part~ o oleylamine + 7E0
and 2 parts of 50% hypophosphorous acid are dried and
~ reacted with 286 parts of oleyl chloride at 60-70C. ~or
10 hours~ The quaternized amine ethoxylate mixture is
mixed with 1 part 50% hypophosphorous acid and 28 parts
water. Phosphorus pentoxide, 142 parts, is added ~lowly
under a nitrogen blanket at 40-50C. over 2 hours. The
reaction mixture is heated for 3 hours at 90C., and then
5 parts of water are added. The resulting surfact~nt is
heated an additional 2 hours at 80-90C., cooled to 60C.,
and then 1 part 35% hydrogen peroxide is added. There is
obtained 1,042 parts of surfactant.
EXAMPLE V
As in Example I, 708 parts of stearyl amine +
lOE0, 2 parts of 50% hypophosphorous acid, and 126 parts
of benzyl chloride are reacted at 70-80C. to form the
quaternized amine ethoxylate. This material is then ~ !
reacted with 75 parts of phosphorus oxychloride at
40-50C. over ~ hours. The hydrogen chloride is removed
by nitrogen bubbling to a constant chloride ion content.
The phosphated acid mixture was drowned into 120 parts
of 50% caus~ic soda, to obtain 980 parts of surfactant
solu~ion.
-~5-
7 ~ 3 ~ ~
EXAMPLE VI
The following surfactant compositions can be
employed for different end uses, specified bel~w, in
accordance with ~he following table, Table 1, wherein all
5parts mentioned are defined in terms of weight %.
TABLE 1
Liquid Hard
Drain Steam Surface
Cleaner Degreaser Cleaner
10-Phosphate ester amphoteric
of Example 1 1.0 1.0 1.0
NaOH 9.0 17.0 2.0
TKPP --- - lo.o
Water 90.0 82.0 87.0
Totals 100.0 100.0 100.0
EXAMPLES VII-XII
The present compounds are also applicable as
alkaline hard surface cleaners, exhibiting excellent
caustic stability depending upon the degree of ethoxylation,
anionic functionality, and hydrophobe. Alkali solub-llity
is sh~wn in Table 2.
-16-
330~ ~ ~
TABLE 2
Caustic Solubility - 1% Surfactant Soluble
From O to 100C In ~ % NaO~
Example
No. CO~POUND % NaO~
7Sodium Phosphate of Cocoamine + 5EO
diethyl sulfate 9.4
8Sodium Phosphate of Cocoamine ~ lOEO
diethyl sulfate 6.6
9Sodium Phosphate of Cocoamine ~ 15EO
diethyl sulfate 4.9
10Sodium Phosphate of Cocoamine ~ 20Eo
diethyl sulfate 4.25
11Sodiwm Phosphate of Cocoamine ~ 30EO
diethyl sulfa~e 3.2
12Sodium Phosphate of Cocoamine + 50EO
diethyl sulfate 2.4
EXAMPLE XIII
.
Fabric softeners and detergenttsofteners and
sanitizers can be prepared for use on textiles, and Table 3
bel~w sets forth typical formulations (wherein all
ingredients are in parts by weight %) for such purposes:
TABLE
1 2 3
Present amphoteric surfactant 3-7 10-30 10-30
Distearyl dimethyl ammonium halide -- 3-7 3-7
(n-alkyl dimethyl benzyl) -- ---- 5.10
ammonium halide
Sodium acetate 1-2 ---- ----
Water to 100% to 100% to 100%
-17-
. .
1~733ai9
EXAMPLE XIV
This exampLe is intended to sh~w that khe present
surfactants can be effectively employed in textile soten-
ing compositions. In this example, 5 parts by weight of
the present amphoteric surfactant in 95 parts by weight of
water are neutralized with sodium hydroxide to a pH of 5.5.
This solution, as noted, is a very efficient softener/
antistatic agent for textiles.
In a typical application, the solut~on ~s cliluted
l:lO with distilled water.
Conventional textile fabric substrates are thsn
treated with th0 dilute surfactant solution during
conventional padding of such substrates. The fabrics thus
softened sh~w excellent softness, i.e., pliable to feel,
and complete elimination of static electricity upon drying.
The advantage of this softener over conventional
cationic softeners is that it can be washed out during
subsequent laundering, whereas the cationic softeners tend
to build up over repeated applica~ions.
-18-
:
. ~
~73~
.
EXAMPLE XV
In this example there were prepared, according to
the procedure of Example 1 (except for ~he identity and
amount of amine reactant used), (a) the sodium phosphate of
tallowamine + 5E0 diethyl sulfate and (b) the sodium
phosphate of oleylamine ~ 5E0 diethyl sulfate. With respeet
to (a~ 240 parts by weight (0.5 mole) of tallowamine + 5E0
(Ethomeen T/15 of Armak) was used (instead o~ the 0 5 mole
of cocoamine + lOE0 o Example I), and, w~th respect to
(b), 25û parts (0.5 mole) of oleylam~ne ~ 5EO (Ethomeen
0/15 of Armak) was used (instead of the 0.5 mole of
cocoamine ~ lOE0 of Example I).
Then, 0.4% aqueous solutions of (a) and (b) were
prepared, their pH values were adjusted to pH 8.5 with
triethanolamine, and the pH-adjusted solutions evaluated
for use as water-based lubricants. The Falex Load Test was
used to determine the lubricating properties of the
respective solutions, and the foll~wlng results, set forth
below in Table 4, were obtained.
TABLE 4
Sample Load a~ Failure
(l) 0 4% aq. sodium phosphate of
tall~wamine + 5E0 diethyl sulfate4,000 lbs.
(2) 0.4% aq. sodium phosphate of
oleylamine + 5E0 diPthyl sulfate4,250 lbs.
(3) Water (control) 550 lbs.
- 19 -
~733~9~
. These results indicate excellent lubricant
properties.
The products of the instant invent~on may also be
further compounded with other ingredients to provi~e for
the foll~wing uses:
Liquid steam cleaning compounds, floor maintenance products,
wax removers 9 automobile care products, waterless hand
cleaners~ oil tank degreaser, aluminum cleaner, hand
washing compound, sanitizing hand dis~washing or light duty
cleaning compound, pet shampoos, rug and upholstery
shampoos, mothproofing, and the like.
It is obvious that numerous changes and modifica-
tions can be made in the inventlon without departing from
the spirit and scope thereof, and all such obvious
modifications are considered to be within the scope of the
invention.
For example, in a preferred embodiment of this
invention, it has been previously stated that the desired
end products comprise mainly a monoester product and a
diester product. As would be apparent to those skilled in
the art, in view of the foregoing description of this
invention, the mono s~er product would be obtained
predominately when about 2.0 moles of phosphating agent we~e
used per mole of quaternary alkoxylated monoalkyl amine.
Alternatively, the diester product would tend to be the
major product when about 1.0 moles of phosphating agent
were used per mole of quaternary alkoxylated monoal.kyl
-20-
~9733~9
amine. And likewise, the triester product would tend to be
the major product when about 0.5 mole of phosphating agent
was used per mole of quaternary alkoxylated monoalkyl amine. :~
As one used an increasing excess of phosphating agent
beyond about 2.0 moles of phosphating agent, it would be
apparent to those skilled in the art that correspondingly
increased polymerization products would result. Thu~, it
can be seen that obtainment of the numerous, varied types
of phosphated amphoteric product mixtures that are
possible with the practice of this invention can vary
considerably within the scope of this invention, as, e.g.,
with the amounts of phosphating and oxyalkyla~ing agents
used, but all this would represent mere routine
experimentation by and to those skilled in the art.
~5
