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Патент USA US3067153

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United States Patent O?lice
3,057,144
Federated Dec. 4., 1962
2
1
of from about one to three parts of each component in
the mixture, and preferably in a weight ratio of 1:1:1,
respectively. The foregoing mixture may further be
3,067,144
DETERGENT COMPQSH‘IQN
Edwin B. Michaels, Stamford, Comm, assignor to Stam
ford Chemical Industries, The, Stamford, CGEIL, a cor
poration of Delaware
No Drawing. Filed Nov. 16, 1950, Ser. No. 352,980
9 Claims. (Cl. 252-13?)
modi?ed by adding thereto of from about one to ten
parts of any commercially available phosphate builder,
as for instance, an alkali metal tripolyphosphate, a tetral
kali metal pyrophosphate, an alkali metal hexametaphos
phate and equivalents thereof as well as mixtures of the
same; the alkali contemplated include: sodium, potassium,
This invention relates to novel heavy-duty synthetic
detergent compositions which can be successfully em 10 lithium as Well as ammonium radicals. It has been found
that the de?ned compositions are effective when employed
ployed over a wide range of washing temperatures. More
in relatively dilute aqueous concentrations from 0.04%
particularly, the invention is concerned with detergent
to 2.0%, and preferably in concentrations from 0.1%
to 0.3%.
detergent, (2) a higher fatty alcohol of from 10 to 18
It has been further found that a large variety of non
carbon atoms, and (3) a polyalkoxy dihydric alcohol 15
cationic synthetic detergents of the anionic and non-ionic
which may be represented by the formula:
compositions comprising: (1) an organic non-cationic
types either alone or in admixture can be successfully
used herein. These may be taken from the following
/|
20
typical commercially available distinct classes:
(1) Ethylene oxide-higher alkyl phenol condensates in
which the alkyl substituent may contain from 8 to 12
\
A
H
carbon atoms. The condensates, polyoxyethylene ethers,
are prepared by condensing 6 to 30 moles ethylene oxide
with 1 mole of the alkyl-substituted phenol. They are
or an isomer thereof wherein m stands for a whole 25 available commercially under such names as “Igepal
number from about 7 to about 35 and n is an integer
from about 3 to about 14.
It is known that the class of either ionic or nonionic
CA” and “Igepal CO,”
(2) Water soluble salts of the higher fatty acid amides
of lower molecular Weight amino alkyl sulfonic acids,
including, for example,’ the sodium salt of oleic acid
detergents has achieved a distinct status as a substitute for
amide of N-methyl or N-cyclohexyl taurine, known as
natural soap. However, such detergents suffer the dis
“Igepon T” or “Igepon 'CN,” respectively,
advantages of relative inferior detersiveness as compared
(3) Water soluble salts of higher alkyl benzene sul
to natural soap. Moreover, they are substantially in
fonic acid, such as the dodecyl benzene sodium sulfonate,
effective over a wide range of temperatures during use.
sold under the trademark “Nacconol NRSF,”
For many purposes, soap itself is unsatisfactory since
(4) Water soluble salts of alkyl sulfonic acids as, for
it tends to deposit a water insoluble residue, usually in 35
instance, the sodium salt of sulfonated mineral oil,
the form of calcium oleate, upon the washed apparel.
(5) Water soluble salts of the higher alcohol esters
Such deposition inevitably imparts a distinct hard feel
of sulfocarboxylic acids,
thereto. Thus, if non-cationic detergents could be en
(6) Water soluble salts of the higher alkyl sulfates of
hanced whereby the detersiveness of soap is approached
or exceeded without experiencing soap’s disadvantages, 40 10 to 14 carbon atoms, e.g., “Duponol C,”
(7) Water soluble salts of higher fatty acids of mono
such would be highly desirable.
esters of monohydroxy alkyl or polyhydroxy alkyl sul
A principal object of the invention is to provide a de
fonic acid as, for example, the sodium salt of oleic acid
tergent composition of enhanced properties applicable
est-er of isethionic acid (e.g., “Igepon ACE-78”),
over a wide range of temperatures. A further object is
(8) Water soluble salts of the sulfuric acid esters of
to provide a non-cationic detergent composition com 45
the fatty acid monoglycerides as for instance, the sodium
parable to soap’s detersiveness, absent insolubles which
salt of coconut oil fatty acid ester of 1,2-dihydroxy
may precipitate upon the washed apparel. Other ob
propane-3-sulfuric acid, available as-“Syntex T,”
jects and advantages will become apparent from a con
(9) condensates of ethylene oxide-higher fatty acid
sideration of the following detailed description.
Surprisingly, the foregoing objects can be attained in a 50 (or higher fatty alcohols) prepared by reacting 1 mole of
s‘tearic or oleic acid (lauryl or tallow alcohol) with 6 to
straight forward manner by providing a detergent com—
30 moles ethylene oxide and are available under trade
positionv mixture comprising (a) an organic non-cationic
marks such as “Renex” of “Sterox AS” (or Sterox CD,”
detergent, (b) a. higher fatty alcohol and (c) a poly
“Siponic- E”), respectively, and
alkoxy alcohol, hereinafter de?ned. None of the com
ponents, other than the detergent, exhibits any noticeable
detersiveness. Notwithstanding, the presence. of both a
higher fatty alcohol and a polyalkoxy alcohol, a markedly
(10) Polyoxypropylene glycol-ethylene oxide conden
sates preparedby reacting polypropylene oxide and poly
ethylene glycol, available as “Pluronic L—44.”
improved detergent composition has been unexpectedly
found, whereby the major disadvantages of the prior art
pounds exhibits various degrees of detersive activity, its
are obviated.
The compositions of’ my invention may be character
ized as being substantially- wate-r insoluble. They com
prise the' above-mentioned components, all admixed in
Although each of the aforementioned classes of com
60 detergency is markedly enhanced many fold by the
incorporation therein of both a higher fatty alcohol
characterized by the formula:
R—OH
hol and'polyalkox-y alcohol are present on a weight basis 65 where R is analkyl radical of from 10 to 18 carbon
de?nite proportions. The detergent,. higher fatty alco
enemas.
4.
3
atoms and a polyalkoxy dihydric alcohol.
lowing.
The latter
alcohol may be represented by the general formula:
As employed herein, “AATCC” means the
American Association Textile Chemists and Colorists.
In typical runs a standard soiled swatch and stain
less steel balls, together with the speci?ed testing bath
containing 0.2% detergent composition are charged to a
launderometer jar. After a twenty minute wash cycle
at 140° F., the washed swatch is removed from the jar,
rinsed in ordinary tap water of 60 p.p.m. hardness,
based on the presence of calcium and magnesium salts
and isomers thereof, where m is an integer from about 10 and calculated as CaCO3 and Mg2CO3 in a weight ratio
of approximately 2:1. This is performed to illustrate the
7 to about 35 (i.e., average molecular weight of about
enhanced detergency of the compositions of the present
2000) and n is an integer from about 3 to about 14 (i.e.,
invention. Comparisons with known synthetic detergent
average molecular weight of about 250 to 1000).
compositions are made. In the following examples, vari
The polyalkoxy dihydric alcohols may be prepared by
ous detergent compositions with and without the higher
known methods for instance, compound (I) is prepared
alcohol and polymer in admixture are set forth; all parts
by reacting 1 mole of 1,2-propylene glycol with at least
are based on weight, unless otherwise speci?ed. The com
about 6 moles of 1,2-propylene oxide. Resultant poly
positions are then used in the concentrations indicated.
propylene glycol polymer should not exceed a molecular
Re?ectance readings of the soiled and unsoiled, washed
weight (M.W.) of about 2000. Compound (11) can for
example be prepared by reacting 1 mole of 1,2-butylene 20 and unwashed soil swatches are recorded. However, prior
to washing, the reflectance reading of the soiled portion
glycol with at least about 2 moles of 1,2-butylene oxide.
of the standard swatch is recorded at 29, while the un
Powever, the molecular weight (M.W.) of the resultant
soiled portion of the same swatch is recorded at 100.
polybutylene glycol polymer should not exceed about
The percent detergency is determined by the formula:
1000. Although the structures as set forth are the pre
ferred representations of the polyalhoxy alcohols, it is
plated. For example, the polypropoxy linkage of the
Rf (Washed soiled area) -—Rr(standard soiled area)'><100
Rf (standard unsoiled area)~Rf (standard soiled area)
above compounds, may be written as:
where R: is de?ned as the re?ectance reading value.
to be understood that their isomers are also contem
CH3
(Ia)
Several compositions of the following examples illus
CH3
30 trate various embodiments of my invention.
They are
employed to wash swatches that are standardized, im
----(!JB—CH2——O— : —OHz-— H—O—
——CH——CHz—O-—~ : ——CHz-—CH—O~—
(Ila)
(llzHs
printed, oily-type, carbon soiled cotton. The swatches are
(B2115
put in a launderometer maintained at 140° P. which
approximates good laundry practice. The compositions
Thus, (Ia) polypropoxy glycols of average molecular
weight ranging from about 425 to 2000, preferably from 35 are all employed as an aqueous detergent bath which
is adjusted to about 0.03%, based on the weight of the
about 950 to 1200, and (Ila) polybutoxy glycols of
active organic detergent component. However, based
average molecular weight ranging from about 250 to
1000, and preferably from about 450 to 500, are con
on the detergent component concentrations as low as
include: decanol, undecanol, dodecanol, lauryl alcohol,
tridecanol, myristyl alcohol, cetyl alcohol and stearyl
by the appended claims.
0.01% and as high as 0.10% may also be employed
templated in the practice of this invention.
The higher fatty alcohols which are useful in the prac 4.0 advantageously. These examples are merely illustrative
of the preferred modus operandi, and are not intended
tice of the invention possess 10—18 carbon atoms and
to be taken as limitative, except as to the extent de?ned
alcohol, as well as their isomers and mixtures thereof.
EXAMPLE 1
As stated previously, alkali metal phosphate builders
'
are advantageously added to the above-de?ned multi
Parts
Nonyl phenol (1 mole) condensed with 10-11 moles
components compositions. However, other adjuvants
may also be added concomitantly in the present practice.
ethylene oxide ____________________________ __ 14
Lauryl alcohol
Such adjuvants are for instance starch, sodium carboxy
6
Polypropylene glycol polymer (l025—average mo
methyl cellulose, glue, clay, sodium cellulose acetate and 50
lecular weight) ___________________________ __
equivalents, thereof all being added in conventional
The detergent compositions are further characterized
as being substantially water insoluble. They are, how
ever, dispersible in water.
The indications are that a 55
12
Tetrapotassium polyphosphate _________________ __ 25
amounts.
EXAMPLEZ
A composition of Example 1 is prepared except that the
quantity of the polypropylene glycol polymer is increased
'to 16 parts of said polymer.
cloudy solution appears at elevated temperatures of 120°
F. or higher above. if desired, a wetting agent other
than the detergent itself may be advantageously added
EXAMPLE 3
to the composition in an amount approximating the
Parts
quantity of synthetic detergent, so as to solubilize the 60 Polyoxyethylene ether of oleyl alcohol (prepared by
latter, particularly in a high phosphate salt environment.
reacting 12 moles of ethylene oxide per mole of
Such wetting agents include, for instance, the soluble
oleyl alcohol) ____________________________ __ 10
salts either of xylene sulfonates, or of alkylsulfo-suc
cinates, or of long chain fatty acid sulfates, or of un
polyrnerized alkyl naphthalenesulfonic acids. More spe
ci?cally, wetting agents such as sodium xylene sulfonate,
lauryl sodium sulfate, dioctyl sodium sulfosuccinate and
potassium isopropyl naphthalene sulfonate are contem
plated herein. In general, any of the commercially
available wetting agents may be used.
Decanol
Polypropylene glycol polymer (average molecular
weight=1025)
___
__
5
Tetrasodium pyrophosphate ___________________ __ 25
EXAMPLE 4
7
Parts
Condensate of 1 mole of tallow alcohol and 11 moles
The enhanced detergent properties of the composi
of ethylene oxide _________________________ __ 10
tions according to the practice of the present invention
Tridecanol
are determined in a conventional manner.
Polypropylene glycol polymer (average molecular
The latter
requires the use of a launderometer as fully described
in the “AATCC” year book for 1955, page 55 and fol 75
_________________________________ __
weight=l025)
____________________________ c-
5
6
Tetrasodium pyrophosphate __________________ __ 25
3,067,144
6
The re?ectance data was collected and recorded in the
EXAMPLE 5
table as follows.
For the condensate of tallow alcohol and ethylene oxide
of Example 4 is substituted sodium lauryl sulfate and the
Table 1
composition therein otherwise identical, is prepared.
Br
Ex.
EXAMPLE 6
The components of the composition in Example 4 are
admixed as indicated, except that sodium dodecyl benzene
sulfonate is substituted for the condensate of tallow al
cohol and ethylene oxide.
Rn?
v(soiled
portion
Percent
deter-
soiled
portion
Percent
deter-
Percent
increase
Temp,
of swatch
after
gencyl
altercleaning
ge'neyl
in detergency
° F.
82
75
50
30 Y
150
140
84
86
78
80
50
53
30
354
160
1120
140
120
71
84
59
78
60
5,8
43
41
36
90
140
140
cleaning)
84
EXAMPLE7
Parts
Tridecyl alcohol ‘(1 mole) condensed with ethylene
78
45
23
76
66
56
38
82
77
80
75
68
49
49
54
28
28
35
72
250
160
74 r
160
165
140
100
7140
160
140
oxide (10 moles) ___________________________ __ 5
Tetradecanol
________________________________ __ 5
1 As de?ned above.
Polypropylene glycol polymer (average molecular
I
2 Ru and percent detergeney are determined in usual manner utilizing
detergent compositions of the respective examples in which the alcohol
weight +425) ___________ __ ________________ __ 5 20 and the polymer have been omitted. Percent increase in detergeney is
determined by comparing the compositions of the invention to that of
Tetrasodium pyrophosphate ____________________ __ 5
the prior art.
In the above table, the water hardness (Ca-Mg) in
parts per million utilized in each of the examples except
Parts
25 ing Example 4 is 60. However, the water hardness used
Tridecyl alcohol (1 mole) condensed with ethylene
in Example 4 is 200.
oxide (8 moles) __________________________ __
5
EXAMPLE 11
Tridecyl alcohol ___________________________ __
5
A mixture is prepared which comprises 105 parts of
Polypropylene glycol polymer (average molecular
EXAMPLE 8
weight=2000)
decanol, 10.5 parts of polypropylene glycol polymer of
___________________________ __
30 average molecular weight equal to about 1025, 15 parts
iTetrasodium pyrophosphate __________________ __ 100
Carboxymethylcellulose _____________________ __
1
Sodium metasilicate ________________________ __
25
sodium salt of oleic acid amide of N-methyl taurine and
15 parts of tetrapotassium pyrophosphate. T0 this mix
ture is added 30 parts sodium xylene sulfonate. Suf?cient
water is added to increase the total number of parts of
The enhanced detergency property of the above-de?ned 35 the composition to 185. The wetting agent, sodium xylene
compositions has been noted at the usual laundry tem
sulfonate, is advantageously added principally to e?ect
erature of 140° F. However, temperatures as low as
solubilization of the detergent to form a substantially
room temperature and as high as 200° F. may be used
clear solution.v When the stated composition is employed
herein.
In general, temperatures in the range of 120° C.-160° 40 in dilute aqueous concentration of 0.3%, 0.4% and 0.5%,
respectively, re?ectance readings subsequent to washing
C. are preferred when using the C12 alcohols, 140°-180°
at 140° F. are 75, 76v and 84, respectively.
F. when employing the C14 alcohols and 160° to 210° F.
EXAMPLE 12
A mixture was prepared containing/V the ingredients:
when using the C1648 alcohols.
EXAMPLE 9
Parts
45
(1') Condensate of 12 moles ethylen oxide andil mole
'
Parts
‘of oleyl
Polyoxyethylene ether of stearyl alcohol prepared by
reacting one mole of stearyl alcohol with 12 moles
of ethylene oxide __________________________ __
Commercial lauryl alcohol (70% C12, 20% C14, 10%
Cid-l8)
taurine
5 50
_______ __,_ ____ n, _______ __
6
_____________ ___ ____ ___ ___________ __
(4)
5
Tridecanol
__________ __, _______ ____ _______ __
55
Suf?cient water was then added‘ to dilute the mixture
150 parts.
Parts
Polyoxyethylene ether of stearyl alcohol (prepared
by reacting one mole of stearyl alcohol with 12
moles of ethylene oxide ____________________ __
5
Myristyl alcohol _____________________________ __
3
8
10
(5) Sodium-xylene sulfonate __________________ __ 40
(6) Tetrasodium pyrophosphate _______________ __ 11
Tetrasodium pyrophosphate __________________ __ 25
EXAMPLE 10
10
(3) Polybutylene glycol’ polymer (av. mol. wt. of
1000)v ___________________ __,_______v___.______
-------------------------------- —-.-~
Polypropylene glycol polymer _________________ __
alcohol
('2) Sodium salt of oleic acid amide of; N-methyl
A
When a test soiled swatch in a launderometer at 140° F.
as described previously is’ washed using 0.3% concentra
tion of the foregoing detergentpcomposition, aid-re?ectance
60 reading of 78 is ‘observed.
Polyproylene glycol polymer (av. mol. wt. 1200)____ 5
EXAMPLE 13
The above, Example 12 was repeated; in every, respect
Tetrasodium pyrophosphate ____ ______________ ______ 25
except the polybutylene glycol polymer was. replaced by
Although it is generally recognized in the laundry art
molecular weightof about 500., When the soiled swatch
vention. Further, even in the absence of soft water and
where hard water is used (200+ p.p.m. Ca-Mg cal
mixing the components together in the form of a. dry mix<
ture, dispersion, suspension ,andthe like, either in the pres
6 parts of polybutylene glycol polymer of. an average
is washed in the detergent compositioma re?ectance read
that an increase in washing temperature above about 140°
ing of 76 is observed,
F. decreased the detergency value of the synthetic deter
It is an important advantage of‘ the present invention
gent swiftly, surprisingly, a contrary effect is noted with
the enhanced detergent compositions of the: present in 70 that the detergent compositions can be prepared by ad
ence or absence of additional alkali metal phosphates.
culated as CaCO3 and Mg2CO3 in 2:1 weight ratio), the
In this fashionLthe compositions can be packaged with
re?ectance reading of the unsoiled area of the standard
75 ease.
cotton swatch is noted in each case to be 999+.
3,067,144
7
8
EXAMPLE 14
n is an integer from about 3 to about 14, and isomers
thereof, and
A 25 pound load of soiled white shirts and containing
(d) 1 to 10 parts by weight of ‘an alkali metal phos
phate builder selected from the class consisting of
a standard soiled swatch is charged to a conventional
commercial washer containing hot water (160° F.). To
the latter is next charged 8 ounces of detergent consisting
of 14 parts of a condensate prepared by reacting 1 mole
tridecanol and 12 moles of ethylene oxide, 6 parts of
an alkali metal pyrophosphate and a mixture of an
alkali metal pyrophosphate and an alkali metal ortho
phosphate.
2. The detergent composition of claim 1 in which the
Weight ratio is 1:1: 1:5 of the components, respectively.
phosphates comprising tetrasodium pyrophosphate (50%), 10 3. The ‘detergent composition of claim 1 in which the
non-cationic detergent is the condensate of 1 mole of
trisodium phosphate (49%) and carboxymethylcellulose
nonyl phenol and about 10 moles of ethylene oxide; the
(1%). After a ten minute washing cycle, the wash Water
fatty alcohol is lauryl alcohol, the polyalkoxy alcohol is
is discarded and the wash is further treated ‘for an addi
polypropylene glycol polymer of average molecular
tional ten minutes with four ounces of the above deter~
gent composition previously defined. The wash water is 15 weight 1025; and the alkali metal phosphate is tetrasodium
pyrophosphate.
discarded again, the load is bleached, rinsed ?rst with
4. The detergent composition of claim 1 in which the
hot water, then with cool water and, ?nally, dried.
detergent
is the condensate of 1 mole of octyl phenol and
Re?ectance reading of the standard swatch included
about 8 moles of ethylene oxide; the fatty alcohol is
along with the shirts is observed as 95 (93% detergency),
decanol; the polyalkoxy alcohol is polypropylene glycol
and none of the washed shirts had to be withdrawn from
polymer
of average molecular weight equal to about 1025;
the load to be rewashed for cuff or collar stains and soils.
and the alkali metal phosphate is tetrapotassium pyro
The percent whiteness retention was found to be 100%.
phosphate.
'
EXAMPLE l5
5. The detergent composition of claim 1 in which the
Repeating the procedure of Example 14 in every mate 25 detergent is the condensate of 1 mole of oleyl alcohol
rial detail except that natural soap is substituted for the
and 12 moles of ethylene oxide; the fatty alcohol is tri
synthetic detergent mixture, a re?ectance reading taken
decanol; the polyalkoxy alcohol is polypropylene glycol
polymer of average molecular weight equal to 1025; and
on the included test soiled swatch is noted as 53.5 (35%
the alkali metal phosphate is tetrasodium pyrophosphate.
detergency) and the whiteness retention is recorded as
6. The detergent composition of claim 1 in which the
99.5%. However, more than one-fourth of the load used 30
detergent is the condensate of 1 mole of tallow alcohol
in this example had to be rewashed for cuff and collar
and 11 moles of ethylene oxide; the fatty alcohol is tri
stains.
decanol; the polyalkoxy alcohol is polypropylene glycol
It will be readily noted that in comparing the values
polymer of average molecular weight equal to 1025; and
of Examples 14 and 15, the detergent mixture of this in
vention represents a more than 150% increase of soil re 35 the alkaline metal phosphate is tetrasodium pyrophos
lauryl alcohol and 8 parts polypropylene glycol polymer
(average molecular weight 1025) and 120 parts of mixed
phate.
moval over soap.
7. The detergent composition of claim 1 in which the
organic detergent is a mixture which consists essentially
I claim:
1. An improved multi-component cleaning and laundry
detergent composition substantially water insoluble which
consists essentially of:
v
v
of the condensate of 12 moles ethylene oxide and 1 mole
40 of oleyl alcohol and the sodium salt of oleic acid amide
of N-methyl taurine; the polyalkoxy alcohol in poly
butylene glycol polymer of average molecular weight
equal to about 1000; the fatty alcohol is tridecanol; and
the alkali metal phosphate is tetrasodium pyrophosphate.
(a) l to _3 parts by weight of a non-cationic organic
synthetic detergent selected from the class con
sisting of ethylene oxide—higher alkyl phenol
condensates, water soluble salts of high fattty acid
amides of lower molecular weight amino alkyl sul 45
8. The detergent composition of claim 1 in which the
fonic acid, water soluble salts of higher alkyl ben
detergent is the condensate of 1 mole of stearyl alcohol
zene sulfonic acid, water soluble salts of alkyl sul
and 12 moles of ethylene oxide; the alcohol is lauryl
fonic acids, water soluble salts of higher alcohol
alcohol; the polyalkoxy alcohol is polypropylene glycol
esters of sulfocarboxylic acids, water soluble salts of
polymer of average molecular weight equal to about 1200;
50
the higher alkyl sulfates, water soluble salts of higher
and the alkali metal phosphate is tetrapotassium pyro
fatty acids of monoesters of monohydroxy alkyl sul
phosphate.
fonic acids, water soluble salts of higher fatty acids
9. The detergent composition of claim 1 in which the
of monesters of polyhydroxy alkyl sulfonic acid,
detergent is the condensate of 1 mole of stearyl alcohol
water soluble salts of the sulfuric acid esters of fatty
acid monoglycerides, condensates of ethylene oxide 55 and 12 moles of ethylene oxide; the fatty alcohol is
and higher fatty acids, condensates of ethylene oxide . undecanol; the polyalkoxy alcohol is polypropylene glycol
polymer of average molecular weight equal to 1025; and
and higher fatty alcohols and polyoxypropylene gly
the alkali phosphate is tetrasodium pyrophosphate.
col-ethylene oxide condensates.
(b) 1 to 3 parts by weight of a fatty alcohol character
60
ized by the general formula:
References Cited in the ?le of this patent
ROH
UNITED STATES PATENTS
where R is an alkyl group of from 10 to 18 carbon
atoms.
(0) 1 to 3 parts by weight of a polyalkoxy dihydric 65
alcohol characterized by and selected from the struc
ture consisting of:
_/ _ H L
OH \ZH O rojm
and
/
H
Jacoby et al ___________ __ Nov. 13, 1951
2,806,001
Fong et a1 ____________ __ Sept. 10, 1957
2,855,367
Buck __________________ __ Oct. 7, 1958
FOREIGN PATENTS
70
Hz
2,575,276
729,531
Great Britain __________ __ May 4, 1955
OTHER REFERENCES
“Synthetic Organic Chemicals,” pub. by Carbide and
where m .is an integer from about 7 to about 35 and 75 Carbon Chem. (30., 13th ed., 1952, page 56.
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