CA2305351A1

CA2305351A1 - Process for making a high density granular detergent composition containing mid-chain branched surfactants

Info

Publication number: CA2305351A1
Application number: CA002305351A
Authority: CA
Inventors: Fukuji Ebihara; Teruaki Tatsuno; Takashi Kazuta; Yasuhiko Shibuya; Michael Chris Jensen
Original assignee: Individual
Current assignee: Procter and Gamble Co
Priority date: 1997-10-10
Filing date: 1998-10-09
Publication date: 1999-04-22
Also published as: BR9812756A; JP2001520271A; CN1281505A; WO1999019453A1; EP1021521A1

Abstract

A process which produces a compact granular detergent composition directly from mid-chain branched surfactants and other starting detergent ingredients is disclosed. The mid-chain branched surfactants are mid-chain branched primary alkyl sulfate surfactants and mid-chain branched primary alkyl alkoxylated sulfate surfactants having an average of greater than 14.5 carbon atoms. The process involves mixing a surfactant paste and drying detergent ingredients, spray drying the resulting slurry, compacting the spray dried granules, grinding and coating the granules to form the finished detergent product.

Description

FIELD OF THE INVFNTTnN
The present invention generally relates to processes for producing a granular detergent composition. More particularly, the invention is directed to processes during which a high density detergent composition is produced from starting detergent materials, one of which is a mid-chain branched surfactant. The mid-chain branched surfactants are mid-chain branched primary alkyl sulfate surfactants and mid-chain branched primary alkyl alkoxylated sulfate surfactants having an average of greater than 14.5 carbon atoms. The process produces a free flowing, granular detergent composition which can be commercially sold as a modern compact detergent product.
BACKGROUND OF THE INV NTION
Recently, there has been considerable interest within the detergent industry for laundry detergents which are "compact" and therefore, have low dosage volumes.
To facilitate production of these so-called low dosage detergents, many attempts have been made to produce high bulk density detergents, for example with a density of 600 g/I or higher. The low dosage detergents are currently in high demand as they conserve resources and can be sold in small packages which are more convenient for consumers.
Generally, there are two primary types of processes by which detergent granules or powders can be prepared. The first type of process involves spray-drying an aqueous detergent slurry in a spray-drying tower to produce highly porous detergent granules. In the second type of process, the various detergent components are dry mixed after which they are agglomerated with a binder such as a nonionic or anionic surfactant.
In both processes, the most important factors which govern the density of the resulting detergent granules are the density, porosity and surface area of the various starting materials and their respective chemical composition.
There has been interest in the art for providing processes which increase the density of detergent granules or powders. Particular attention has been given to densification of spray-dried granules by post tower treatment. For example, one attempt involves a batch process in which spray-dried or granulated detergent powders containing sodium tripolyphosphate and sodium sulfate are densified and spheronized in a Marumerizer~.

WO 99/19453 PC'f/US98/21420 This apparatus comprises a substantially horizontal, roughened, rotatabie table positioned within and at the base of a substantially vertical, smooth walled cylinder.
This process, however, is essentially a batch process and is therefore less suitable for the large scale production of detergent powders. More recently, other processes have developed for increasing the density of "post-tower" or spray dried detergent granules.
Typically, such processes require a first apparatus which pulverizes or grinds the granules and a second apparatus which increases the density of the pulverized granules by agglomeration. These processes achieve the desired increase in density by treating or densifying "post tower" or spray dried granules. However, typical "post tower" processes have been largely unsuccessful in producing granular detergent products having acceptable flow properties and particle size regularity. Thus, there remains a need for a process which produces a compact granular detergent product having acceptable flow and particle size properties (i.e., a more narrow particle size distribution).
Furthermore, it has been long-established practice for detergent formulators to use surfactants and combinations thereof in detergent compositions. By way of example, various anionic surfactants, especially the alkyl benzene sulfonates, alkyl sulfates, alkyl alkoxy sulfates and various nonionic surfactants, such as alkyl ethoxylates and alkylphenol ethoxylates are commonly used in detergent formulations. Surfactants have found use as detergent components capable of the removal of a wide variety of soils and stains. A
consistent effort, however, is made by detergent manufacturers to improve detersive properties of detergent compositions by providing new and improved surfactants. A
problem commonly associated with anionic surfactants is their sensitivity to cold water and/or hard water. Improved cleaning performance above and beyond current standards, especially for granular detergent compositions to be used under colder wash water conditions and/or in hard water, has been difficult to attain. Therefore, it would be desirable to have a process for making a detergent composition which exhibits improved cleaning performance over a wide variety of soils and stains.
Accordingly, there remains a need in the art for a process which produces a compact granular detergent product having acceptable flow and particle size properties (i.e., a more narrow particle size distribution). There is also a need in the art for such a process which includes a surfactant which exhibits improved cleaning performance over a wide variety of soils and stains. Also, there remains a need for such a process which is more efficient and economical to facilitate large-scale production of low dosage or compact detergents.
The following references are directed to densifying spray-dried granules:
Appel et al, U.S. Patent No. 5,133,924 (Lever); Bortolotti et al, U.S. Patent No.
5,160,657 (Lever);

Johnson et al, British patent No. 1,517,713 (Unilever); and Curtis, European Patent Application 451,894. The following references are directed to producing detergents by agglomeration: Beerse et al, U.S. Patent No. 5,108,646 (Procter & Gamble);
Hollingsworth et al, European Patent Application 351,937 (Unilever); Swatting et al, U.S.
Patent No.
5,205,958; and Capeci et al, U.S. Patent No. 5,366,652 (Procter & Gamble).
U.S. 3,480,556 to deWitt, et al., November 25, 1969, EP 439,316, published by Lever July 31, 1991, and EP 684,300, published by Lever November 29, 1995, describe beta-branched alkyl sulfates. EP 439,316 describes certain laundry detergents containing a specific commercial C 14/C 15 branched primary alkyl sulfate, namely LIAL 145 sulfate.
This is believed to have 61% branching in the 2-position; 30% of this involves branching with a hydrocarbon chain having four or more carbon atoms. U.S. 3,480,556 describes mixtures of from I 0 to 90 parts of a straight chain primary alkyl sulfate and from 90 to 10 parts of a beta branched (2-position branched) primary alcohol sulfate of formula:

wherein the total number of carbon atoms ranges from 12 to 20 and R1 is a straight chain alkyl radical containing 9 to 17 carbon atoms and R2 is a straight chain alkyl radical containing 1 to 9 carbon atoms (67% 2-methyl and 33% 2-ethyl branching is exemplified).
As noted hereinbefore, R.G. Laughlin in "The Aqueous Phase Behavior of Surfactants", Academic Press, N.Y. (1994) p. 347 describes the observation that as branching moves away from the 2-alkyl position towards the center of the alkyl hydrophobe there is a lowering of Krafft temperatures. See also Finger et al., "Detergent alcohols - the effect of alcohol structure and molecular weight on surfactant properties", J.
Amer. Oil Chemists' Society, Vol. 44, p. 525 (1967) and Technical Bulletin, Shell Chemical Co., SC:
364-80.
EP 342,917 A, Unilever, published Nov. 23, 1989 describes laundry detergents containing a surfactant system in which the major anionic surfactant is an alkyl sulfate having an assertedly "wide range" of alkyl chain lengths (the experimental appears to involve mixing coconut and tallow chain length surfactants).
U.S. Patent 4,102,823 and GB 1,399,966 describe other laundry compositions containing conventional alkyl sulfates.
G.B. Patent 1,299,966, Matheson et al., published July 2, 1975, discloses a detergent composition in which the surfactant system is comprised of a mixture of sodium tallow alkyl sulfate and nonionic surfactants.
Methyl- substituted sulfates include the known "isostearyl" sulfates; these are typically mixtures of isomeric sulfates having a total of I 8 carbon atoms.
For example, EP
401,462 A, assigned to Henkel, published December 12, 1990, describes certain isostearyl alcohols and ethoxylated isostearyl alcohols and their sulfation to produce the corresponding alkyl sulfates such as sodium isostearyl sulfate. See also K.R.
Wormuth and S. Zushma, Langmuir, Vol. 7, ( 1991 ), pp 2048-2053 (technical studies on a number of branched alkyl sulfates, especially the "branched Guerbet" type); R. Varadaraj et al., J.
Phys. Chem., Vol. 9S, (1991), pp 1671-1676 (which describes the surface tensions of a variety of "linear Guerbet" and "branched Guerbet"- class surfactants including alkyl sulfates); Varadaraj et al., J. Colloid and Interface Sci., Vol. 140, (1990), pp 31-34 (relating to foaming data for surfactants which include C 12 and C 13 alkyl sulfates containing 3 and 4 methyl branches, respectively); and Varadaraj et al., Langmuir, Vol. 6 (1990), pp 1376-1378 (which describes the micropolarity of aqueous micelIar solutions of surfactants including branched alkyl sulfates).
"Linear Guerbet" alcohols are available from Henkel, e.g., EUTANOL G-16.
Primary alkyl sulfates derived from alcohols made by Oxo reaction on propylene or n-butylene oligomers are described in U.S. Patent 5,245,072 assigned to Mobil Corp. See also: U.S. Patent 5,284,989, assigned to Mobil Oil Corp. (a method for producing substantially linear hydrocarbons by oligomerizing a lower olefin at elevated temperatures with constrained intermediate pore siliceous acidic zeolite), and U.S. Patents 5,026,933 and 4,870,038, both to Mobil Oil Corp. (a process for producing substantially linear hydrocarbons by oligomerizing a lower olefin at elevated temperatures with siliceous acidic ZSM-23 zeolite).
See also: Surfactant Science Series, Marcel Dekker, N.Y. (various volumes include those entitled "Anionic Surfactants" and "Surfactant Biodegradation", the latter by R.D.
Swisher, Second Edition, publ. 1987 as Vol. 18; see especially p.20-24 "Hydrophobic groups and their sources"; pp 28-29 "Alcohols" , pp 34-3S "Primary Alkyl Sulfates" and pp 3S-36 "Secondary Alkyl Sulfates"); and literature on "higher" or "detergent"
alcohols from which alkyl sulfates are typically made, including: CEH Marketing Research Report "Detergent Alcohols" by R.F. Modler et al., Chemical Economics Handbook, 1993, 609.5000 - 609.5002; Kirk Othmer's Encyclopedia of Chemical Technology, 4th Edition, Wiley, N.Y., 1991, "Alcohols, Higher Aliphatic" in Vol. 1, pp 86S-913 and references therein.
The present invention meets the aforementioned needs in the art by providing a process which produces a compact granular detergent composition directly from mid-chain branched surfactants and other starting detergent ingredients. The mid-chain branched surfactants are mid-chain branched primary alkyl sulfate surfactants and mid-chain branched primary alkyl alkoxoxylated sulfate surfactants having an average of greater than 14.5 carbon atoms. The process involves mixing a surfactant paste and drying detergent ingredients, spray drying the resulting slurry, compacting the spray dried granules, grinding and coating the granules to form the finished detergent product. The detergent compositions resulting from the processes of the invention have acceptable flow properties, a narrow particle size distribution, and exhibit improved cleaning performance over a wide variety of stains and/or soils, even under relatively high water hardness and low temperature wash water conditions.
All percentages and ratios used herein are expressed as percentages by weight (anhydrous basis) unless otherwise indicated. All documents are incorporated herein by reference. All viscosities referenced herein are measured at 70°C
(t5°C) and at shear rates of about 10 to 100 sec-1.
In accordance with one aspect of the invention, a process for preparing a crisp, free flowing, high density detergent composition is provided. The process comprises the steps of (A) continuously mixing a detergent surfactant paste and dry starting detergent material into a mixer to obtain a slurry, the surfactant paste containing mid-chain branched surfactant compounds of the formula:
Ab-X-B
wherein:
(a) Ab is a hydrophobic C9 to C22, total carbons in the moiety, preferably from about C12 to about C 18, mid-chain branched alkyl moiety having: ( 1 ) a longest linear carbon chain attached to the - X - B moiety in the range of from 8 to 21 carbon atoms; (2) one or more CI - C3 alkyl moieties branching from this longest linear carbon chain; (3) at least one of the branching alkyl moieties is attached directly to a carbon of the longest linear carbon chain at a position within the range of position 2 carbon, counting from carbon # 1 which is attached to the - X - B moiety, to position w - 2 carbon, the terminal carbon minus 2 carbons; and (4) the surfactant composition has an average total number of carbon atoms in the Ab-X moiety in the above formula within the range of greater than 14.5 to about 18, preferably from about 15 to about 17; (b) B is a hydophilic moiety selected from sulfates, sulfonates, amine oxides, polyoxyalkylene, alkoxylated sulfates, polyhydroxy moieties, phosphate esters, glycerol sulfonates, polygluconates, polyphosphate esters, phosphonates, sulfosuccinates, sulfosuccaminates, polyalkoxylated carboxylates, glucamides, taurinates, sarcosinates, glycinates, isethionates, dialkanolamides, monoalkanolamides, monoalkanolamide sulfates, diglycolamides, diglycolamide sulfates, glycerol esters, glycerol ester sulfates, glycerol ethers, glycerol ether sulfates, polyglycerol ethers, polyglycerol ether sulfates, sorbitan esters, polyalkoxylated sorbitan esters, ammonioalkanesuifonates, amidopropyl betaines, alkylated quats, alkyated/polyhydroxyalkylated quats, alkylated quats, alkylated/polyhydroxylated oxypropyl quats, imidazolines, 2-yl-succinates, sulfonated alkyl esters, and sulfonated fatty acids; and (c) X is -CH2-; (B) spray drying the slurry to for spray dried granules; (C) compacting the spray dried granules in a compactor to form compacted granules;
(D) grinding the compacted granules to form ground detergent particles; and (E) coating the detergent particles with a coating agent, thereby forming the high density detergent composition.
Accordingly, it is an object of the present invention to provide a process for producing a compact granular detergent product having acceptable flow and particle size properties (i.e., a more narrow particle size distribution). It is also an object of the invention to provide such a process which includes a surfactant which exhibits improved cleaning performance over a wide variety of soils and stains. Also, it is an object of the invention to provide a process which is more efficient and economical to facilitate large-scale production of low dosage or compact detergents. These and other objects, features and attendant advantages of the present invention will become apparent to those skilled in the art from a reading of the following detailed description of the preferred embodiment and the appended claims.
BRIEF DESCRIPTION OF T D AWINC'.
FIG. 1 is a flow chart illustrating a preferred process in which the various steps of the process are serially positioned in accordance with the invention The present process is used in the production of a compact granular detergent composition using starting detergent ingredients including a mid-chain branched surfactant by way of a series of processing steps including a spray drying step and additional "post-tower" steps. By "post-tower" detergent granules, it is meant those detergent granules which have been processed through a conventional spray-drying tower or similar apparatus.
Reference is now made to Fig. 1 which presents a flow chart illustrating the process and various embodiments thereof. In the first step of the process, the invention entails continuously mixing into a mixer or crutcher starting detergent ingredients including a surfactant paste which includes the mid-chain branched surfactant and a dry starting detergent materials, together which form a slurry 10. On a finished detergent product basis, the surfactant paste preferably comprises water and from about 25% to about 75%, preferably from about 35% to about 65% and, most preferably from about 38% to about 55%, of the surfactants one of which is the mid-chain branched surfactant which is described in detail hereinafter. Preferably, the dry starting detergent material comprises from about 10% to about 50%, preferably from about 15% to about 45% and, most preferably from about 20% to about 40% of an aluminosilicate or zeolite builder and from about 10% to about 40%, preferably from about 15% to about 30% and, most preferably from about I S% to about 25% of a sodium carbonate. It should be understood that additional starting detergent ingredients several of which are described hereinafter may be mixed into the mixer or crutcher without departing from the scope of the invention.
The next step of the process involves spray drying 12 the slurry 10 by inputted or spraying the slurry into a spray drying tower or equivalent apparatus to form spray dried granules 14. The spray dried 14 granules have a density of from about 350 g/1 to about 550 g/1 as they exiting the spray drying step 12. One or more spray-drying towers may be employed to manufacture granular laundry detergents which often have a density of about 500 g/1 or less. In this procedure, an aqueous slurry of various heat-stable ingredients in the final detergent composition are formed into homogeneous granules by passage through a spray-drying tower, using conventional techniques, at temperatures of about 175°C to about 225°C.
Thereafter, the spray dried granules 14 are sent to compacting apparatus for the compaction step 16 of the process. In this step, the spray dried granules are compacted to form compacted granules 18 which have a density of from about 1000 g/1 to about 1700 g/l.
The compacted granules 18 are sent to grinding apparatus for the grinding step 20 of the process. Any known conventional compacting and grinding apparatus can be used herein In the grinding step 20, ground detergent particles 22 are formed. Optionally, oversized ground particles 24, typically having a median particle size greater than about 1150 microns, can be recycled back to the grinding step 20 for additional grinding to the desired particle size.
The next step of the process entails a coating step 26 in which the ground detergent particles 22 are coated with a coating agent. The coating agent is preferably selected from the group consisting of aluminosilicates, silicates, carbonates and mixtures thereof. The coating agent not only enhances the free flowability of the resulting detergent composition which is desirable by consumers in that it permits easy scooping of detergent during use. It is preferable to conduct the coating step in a moderate speed mixer such as a Lodige KM
(Ploughshare) mixer, Drais~ K-T 160 mixer or similar brand mixer. The main centrally rotating shaft speed is from about 30 to about 160 rpm, more preferably from about 50 to about 100 rpm. The mean residence time in the moderate speed mixer is preferably from about 0.1 minutes to about 10 minutes, most preferably the residence time is about 0.5 minutes to about 6 minutes. The mean residence time can be conveniently and accurately measured by dividing the tear weight of the mixer/densifier at steady state by the throughput (e.g., kg/hr).
Optionally, a liquid such as a nonionic surfactant can be inputted to the moderate speed mixer. The binder is preferably selected from the group consisting of water, anionic surfactants, nonionic surfactants, polyethylene glycol, polyvinyl pyrrolidone polyacrylates, citric acid and mixtures thereof. Other suitable binder materials including those listed herein are described in Beerse et al, U.S. Patent No. 5,108,646 (Procter &
Gamble Co.).
The liquid distribution is accomplished by cutters, generally smaller in size than the rotating shaft, which preferably operate at about 3600 rpm. Most preferably, the coating step 26 occurs in one ore more, preferably four, serially positioned mixers as described previously. The resulting high density detergent composition 28 exiting the coating step 26 has a density of from about 650 g/I to about 950 g/l, more preferably from about 700 g/I to about 900 g/1.
Optionally, the last step of the process can be an admixing step 30 in which admixing adjunct detergent ingredients to the high density detergent composition 28.
Preferably, the adjunct detergent ingredients are selected from the group consisting of enzymes, detergent builders, bleaching agents, bleach activators, dyes, soil release agents, and mixtures thereof. By including the aforementioned adjunct ingredients, the resulting high density detergent composition 32 is fully formulated and ready for commercially marketing.
The surfactant paste includes surfactant mixtures comprising mid-chain branched surfactant compounds as described herein before. In such compositions, certain points of branching (e.g., the location along the chain of the R, R1, and/or R2 moieties in the above formula) are preferred over other points of branching along the backbone of the surfactant.
The fonmula below illustrates the mid-chain branching range (i.e., where points of branching occur), preferred mid-chain branching range, and more preferred mid-chain branching range for mono-methyl branched alkyl Ab moieties useful according to the present invention.
CH3CH2CH2CH2CH2CH2(CH2)1_~CH2CH2CH2CH2CH2 more preferred ran g preferred range mid-chain branching ran It should be noted that for the mono-methyl substituted surfactants these ranges exclude the two terminal carbon atoms of the chain and the carbon atom immediately adjacent to the -X
- B group.
The formula below illustrates the mid-chain branching range, preferred mid-chain branching range, and more preferred mid-chain branching range for di-methyl substituted alkyl Ab moieties useful according to the present invention.

CH3CH2CH2CH2CH2CH2(CH2)o-6CH2CH2CH2CH2CH2 more preferred ran g preferred range mid-chain branching range The preferred branched surfactant compositions useful in cleaning compositions according to the present invention are described in more detail hereinafter.
The present invention branched surfactant compositions may comprise two or more mid-chain branched primary alkyl sulfate surfactants having the formula I I I
CH3CH2(CH2}~,~,CH(CH2~CH(CH2}yCH(CH2)ZOS03M
The surfactant mixtures of the present invention comprise molecules having a linear primary alkyl sulfate chain backbone (i.e., the longest linear carbon chain which includes the sulfated carbon atom). These alkyl chain backbones comprise from I2 to 19 carbon atoms; and further the molecules comprise a branched primary alkyl moiety having at least a total of 14, but not more than 20, carbon atoms. In addition, the surfactant mixture has an average total number of carbon atoms for the branched primary alkyl moieties within the range of from greater than 14.5 to about 17.5. Thus, the present invention mixtures comprise at least one branched primary alkyl sulfate surfactant compound having a longest linear carbon chain of not less than 12 carbon atoms or more than 19 carbon atoms, and the total number of carbon atoms including branching must be at least 14, and further the average total number of carbon atoms for the branched primary alkyl chains is within the range of greater than 14.5 to about 17.5.
For example, a C 16 total carbon primary alkyl sulfate surfactant having 13 carbon atoms in the backbone must have 1, 2, or 3 branching units (i.e., R, R1 and/or R2) whereby total number of carbon atoms in the molecule is at least 16. In this example, the C 16 total carbon requirement may be satisfied equally by having, for example, one propyl branching unit or three methyl branching units.
R, Rl, and R2 are each independently selected from hydrogen and C1-C3 alkyl (preferably hydrogen or C 1-C2 alkyl, more preferably hydrogen or methyl, and most preferably methyl), provided R, R1, and R2 are not all hydrogen. Further, when z is I, at least R or R1 is not hydrogen.

Although for the purposes of the present invention surfactant compositions the above formula does not include molecules wherein the units R, Rl, and R2 are all hydrogen (i.e., linear non-branched primary alkyl sulfates), it is to be recognized that the present invention compositions may still further comprise some amount of linear, non-branched primary alkyl sulfate. Further, this linear non-branched primary alkyl sulfate surfactant may be present as the result of the process used to manufacture the surfactant mixture having the requisite one or more mid-chain branched primary alkyl sulfates according to the present invention, or for purposes of formulating detergent compositions some amount of linear non-branched primary alkyl sulfate may be admixed into the final product formulation.
Further it is to be similarly recognized that non-sulfated mid-chain branched alcohol may comprise some amount of the present invention compositions. Such materials may be present as the result of incomplete sulfation of the alcohol used to prepare the alkyl sulfate surfactant, or these alcohols may be separately added to the present invention detergent compositions along with a mid-chain branched alkyl sulfate surfactant according to the present invention.
M is hydrogen or a salt forming cation depending upon the method of synthesis.
Examples of salt forming cations are lithium, sodium, potassium, calcium, magnesium, quaternary alkyl amines having the formula R6-N ~ R4 RS
wherein R3, R4, RS and R6 are independently hydrogen, C1-CZZ alkylene, C4-C22 branched alkylene, C 1-C6 alkanol, C 1-C22 alkenylene, C4-C22 branched alkenylene, and mixtures thereof. Preferred cations are ammonium (R3, R4, RS and R6 equal hydrogen), sodium, potassium, mono-, di-, and trialkanol ammonium, and mixtures thereof.
The monoalkanol ammonium compounds of the present invention have R3 equal to C 1-alkanol, R4, RS and R6 equal to hydrogen; dialkanol ammonium compounds of the present invention have R3 and R4 equal to Cl-C6 alkanol, RS and R6 equal to hydrogen;
trialkanoi ammonium compounds of the present invention have R3, R4 and RS equal to C 1-C6 alkanol, R6 equal to hydrogen. Preferred alkanol ammonium salts of the present invention are the mono-, di- and tri- quaternary ammonium compounds having the formulas:
H3N+CH2CH20H, H2N+(CH2CH2OH)2, HN+(CH2CH20H)3.
Preferred M is sodium, potassium and the C2 alkanol ammonium salts listed above; most preferred is sodium.

Further regarding the above formula, w is an integer from 0 to 13; x is an integer from 0 to 13; y is an integer from 0 to 13; z is an integer of at least I; and w + x + y + z is an integer from 8 to i4.
The preferred surfactant mixtures of the present invention have at least 0.001%, more preferably at least 5%, most preferably at least 20% by weight, of the mixture one or more branched primary alkyl sulfates having the formula i I
CH3CH2(CH2)xCH(CHZ)yCH(CHz)zOS03M
wherein the total number of carbon atoms, including branching, is from 15 to 18, and wherein further for this surfactant mixture the average total number of carbon atoms in the branched primary alkyl moieties having the above formula is within the range of greater than 14.5 to about 17.5; RI and R2 are each independently hydrogen or Ci-C3 alkyl; M is a water soluble cation; x is from 0 to 11; y is from 0 to 11; z is at least 2;
and x + y + z is from 9 to 13; provided R1 and R2 are not both hydrogen. More preferred are compositions having at least 5% of the mixture comprising one or more mid-chain branched primary alkyl sulfates wherein x + y is equal to 9 and z is at least 2.
Preferably, the mixtures of surfactant comprise at least 5% of a mid chain branched primary alkyl sulfate having R1 and R2 independently hydrogen, methyl, provided R1 and R2 are not both hydrogen; x + y is equal to 8, 9, or 10 and z is at least 2.
More preferably the mixtures of surfactant comprise at least 20% of a mid chain branched primary alkyl sulfate having RI and R2 independently hydrogen, methyl, provided RI and R2 are not both hydrogen; x + y is equal to 8,9, or 10 and z is at least 2.
Preferred detergent compositions according to the present invention, for example one useful for laundering fabrics, comprise from about 0.001 % to about 99% of a mixture of mid-chain branched primary alkyl sulfate surfactants, said mixture comprising at least about 5 % by weight of two or more mid-chain branched alkyl sulfates having the formula:

CH3 (CH2)aCH (CHZ~CH2 OS03M
(I) , CH3 (CHZ)dCH (CH2)e CHCHZ OS03M
(II) or mixtures thereof; wherein M represents one or more cations; a, b, d, and a are integers, a+b is from 10 to 16, d+e is from 8 to 14 and wherein further when a + b = 10, a is an integer from 2 to 9 and b is an integer from 1 to 8;
when a + b = 11, a is an integer from 2 to 10 and b is an integer from 1 to 9;
when a + b = 12, a is an integer from 2 to 11 and b is an integer from 1 to I
0;

when a + b = 13, a is an integer from 2 to 12 and b is an integer from 1 to 11;
when a + b = 14, a is an integer from 2 to 13 and b is an integer from 1 to 12;
when a + b = 15, a is an integer from 2 to 14 and b is an integer from 1 to 13;
when a + b = 16, a is an integer from 2 to I 5 and b is an integer from 1 to 14;
when d + a = 8, d is an integer from 2 to ? and a is an integer from 1 to 6;
when d + a = 9, d is an integer from 2 to 8 and a is an integer from 1 to 7;
when d + a = 10, d is an integer from 2 to 9 and a is an integer from I to 8;
when d + a = 11, d is an integer from 2 to 10 and a is an integer from 1 to 9;
when d + a = 12, d is an integer from 2 to 11 and a is an integer from 1 to 10;
when d + a = 13, d is an integer from 2 to I 2 and a is an integer from 1 to 11;
when d + a = 14, d is an integer from 2 to 13 and a is an integer from 1 to 12;
wherein further for this surfactant mixture the average total number of carbon atoms in the branched primary alkyl moieties having the above formulas is within the range of greater than 14.5 to about 17.5.
Further, the present invention surfactant composition may comprise a mixture of branched primary alkyl sulfates having the formula I I I
CH3CH2(CH2h,,,CH(CHZ~CH(CH2h,CH(CH2)ZOS03M
wherein the total number of carbon atoms per molecule, including branching, is from 14 to 20, and wherein further for this surfactant mixture the average total number of carbon atoms in the branched primary alkyl moieties having the above formula is within the range of greater than 14.5 to about 17.5; R, R1, and R2 are each independently selected from hydrogen and C1-C3 alkyl, provided R, RI, and R2 are not all hydrogen; M is a water soluble cation; w is an integer from 0 to 13; x is an integer from 0 to 13; y is an integer from 0 to 13; z is an integer of at least 1; and w + x + y + z is from 8 to 14; provided that when R2 is a CI-C3 alkyl the ratio of surfactants having z equal to i to surfactants having z of 2 or greater is at least about 1:1, preferably at least about 1:5, more preferably at least about 1:10, and most preferably at least about 1:100. Also preferred are surfactant compositions, when R2 is a C I-C3 alkyl, comprising less than about 20%, preferably less than 10%, more preferably less than 5%, most preferably less than 1%, of branched primary alkyl sulfates having the above formula wherein z equals 1.
Preferred mono-methyl branched primary alkyl sulfates are selected from the group consisting of 3-methyl pentadecanol sulfate, 4-methyl pentadecanol sulfate, S-methyl pentadecanol sulfate, 6-methyl pentadecanol sulfate, 7-methyl pentadecanol sulfate, 8-methyl pentadecanol sulfate, 9-methyl pentadecanol sulfate, 10-methyl pentadecanol sulfate, 11-methyl pentadecanol sulfate, 12-methyl pentadecanol sulfate, 13-methyl pentadecanol sulfate, 3-methyl hexadecanol sulfate, 4-methyl hexadecanol sulfate, 5-methyl hexadecanol sulfate, 6-methyl hexadecanol sulfate, 7-methyl hexadecanol sulfate, 8-methyl hexadecanol sulfate, 9-methyl hexadecanol sulfate, 10-methyl hexadecanol sulfate, 11-methyl hexadecanol sulfate, 12-methyl hexadecanol sulfate, 13-methyl hexadecanol sulfate, 14-methyl hexadecanol sulfate, and mixtures thereof.
Preferred di-methyl branched primary alkyl sulfates are selected from the group consisting of 2,3-methyl tetradecanol sulfate, 2,4-methyl tetradecanol sulfate, 2,5-methyl tetradecanol sulfate, 2,6-methyl tetradecanol sulfate, 2,7-methyl tetradecanol sulfate, 2,8-methyl tetradecanol sulfate, 2,9-methyl tetradecanol sulfate, 2,10-methyl tetradecanol sulfate, 2,11-methyl tetradecanol sulfate, 2,12-methyl tetradecanol sulfate, 2,3-methyl pentadecanol sulfate, 2,4-methyl pentadecanol sulfate, 2,5-methyl pentadecanol sulfate, 2,6-methyl pentadecanol sulfate, 2,7-methyl pentadecanol sulfate, 2,8-methyl pentadecanol sulfate, 2,9-methyl pentadecanol sulfate, 2,10-methyl pentadecanol sulfate, 2,11-methyl pentadecanol sulfate, 2,12-methyl pentadecanol sulfate, 2,13-methyl pentadecanol sulfate, and mixtures thereof.
The following branched primary alkyl sulfates comprising 16 carbon atoms and having one branching unit are examples of preferred branched surfactants useful in the present invention compositions:
5-methylpentadecylsulfate having the formula:

6-methylpentadecylsulfate having the formula 7-methyipentadecylsulfate having the formula 8-methylpentadecylsulfate having the formula 9-methylpentadecylsulfate having the formula 10-methylpentadecylsulfate having the formula wherein M is preferably sodium.
The following branched primary alkyl sulfates comprising 17 carbon atoms and having two branching units are examples of preferred branched surfactants according to the presentinvention:
2,5-dimethylpentadecylsulfate having the formula:

2,6-dimethylpentadecylsulfate having the formula 2,7-dimethylpentadecylsulfate having the formula ~OS03M

2,8-dimethylpentadecylsulfate having the formula 2,9-dimethylpentadecylsulfate having the formula 2,10-dimethylpentadecylsulfate having the formula wherein M is preferably sodium.
The present invention branched surfactant compositions may comprise one or more mid-chain branched primary alkyl polyoxyalkylene surfactants having the formula R Rl R2 CH3CH2(CH2h,~,CH(CH2)XCH(CH2h,CH(CH2)z(EO/PO)mOH
The surfactant mixtures of the present invention comprise molecules having a linear primary polyoxyaikylene chain backbone (i.e., the longest linear carbon chain which includes the alkoxylated carbon atom). These alkyl chain backbones comprise from 12 to 19 carbon atoms; and further the molecules comprise a branched primary alkyl moiety having at least a total of 14, but not more than 20, carbon atoms. In addition, the surfactant mixture has an average total number of carbon atoms for the branched primary alkyl moieties within the range of from greater than 14.5 to about 17.5. Thus, the present invention mixtures comprise at least one polyoxyalkylene compound having a longest linear carbon chain of not less than 12 carbon atoms or more than 19 carbon atoms, and the total number of carbon atoms including branching must be at least 14, and further the average total number of carbon atoms for the branched primary alkyl chains is within the range of greater than 14.5 to about 17.5.
For example, a C 16 total carbon (in the alkyl chain) primary polyoxyalkylene surfactant having 1 S carbon atoms in the backbone must have a methyl branching unit (either R, R1 or R2 is methyl) whereby the total number of carbon atoms in the molecule is 16.
R, RI, and R2 are each independently selected from hydrogen and C1-C3 alkyl (preferably hydrogen or C1-C2 alkyl, more preferably hydrogen or methyl, and most preferably methyl), provided R, R1, and R2 are not all hydrogen. Further, when z is l, at least R or R1 is not hydrogen.
Although for the purposes of the present invention surfactant compositions the above formula does not include molecules wherein the units R, R1, and R2,are all hydrogen (i.e., linear non-branched primary polyoxyalkylenes), it is to be recognized that the present invention compositions may still further comprise some amount of linear, non-branched primary polyoxyalkylene. Further, this linear non-branched primary poiyoxyalkylene surfactant may be present as the result of the process used to manufacture the surfactant mixture having the requisite mid-chain branched primary polyoxyalkylenes according to the present invention, or for purposes of formulating detergent compositions some amount of linear non-branched primary poiyoxyalkylene may be admixed into the final product formulation.
Further it is to be similarly recognized that non-alkoxylated mid-chain branched alcohol may comprise some amount of the present invention polyoxyalkylene-containing compositions. Such materials may be present as the result of incomplete alkoxylation of the alcohol used to prepare the polyoxyalkylene surfactant, or these alcohols may be separately added to the present invention detergent compositions along with a mid-chain branched polyoxyalkyiene surfactant according to the present invention.
Further regarding the above formula, w is an integer from 0 to 13; x is an integer from 0 to 13; y is an integer from 0 to 13; z is an integer of at least 1; and w + x + y + z is an integer from 8 to 14.
EO/PO are alkoxy moieties, preferably selected from ethoxy, propoxy, and mixed ethoxy/propoxy groups, more preferably ethoxy, wherein m is at least about 1, preferably within the range of from about 3 to about 30, more preferably from about 5 to about 20, and most preferably from about 5 to about 15. The (EO/PO)m moiety may be either a distribution with average degree of alkoxylation (e.g., ethoxylation and/or propoxylation) corresponding to m, or it may be a single specific chain with alkoxylation (e.g., ethoxylation and/or propoxylation) of exactly the number of units corresponding to m.
The preferred surfactant mixtures of the present invention have at least 0.001 %, more preferably at least 5%, most preferably at least 20% by weight, of the mixture one or more mid-chain branched primary alkyl polyoxyalkylenes having the formula CH3CH2(CH2)xCH(CH2)yCH(CH2)z(EO/PO)mOH
wherein the total number of carbon atoms, including branching, is from 15 to 18, and wherein further for this surfactant mixture the average total number of carbon atoms in the branched primary alkyl moieties having the above formula is within the range of greater than 14.5 to about 17.5; RI and R2 are each independently hydrogen or CI-C3 alkyl; x is from 0 to 11; y is from 0 to 11; z is at least 2; and x + y + z is from 9 to 13; provided RI
and R2 are not both hydrogen; and EO/PO are alkoxy moieties selected from ethoxy, propoxy, and mixed ethoxy/propoxy groups, more preferably ethoxy, wherein m is at least about 1, preferably within the range of from about 3 to about 30, more preferably from about 5 to about 20, and most preferably from about 5 to about 15. More preferred are compositions having at least 5% of the mixture comprising one or more mid-chain branched primary polyoxyalkylenes wherein z is at least 2.
Preferably, the mixtures of surfactant comprise at least 5%, preferably at least about 20%, of a mid chain branched primary alkyl polyoxyalkylene having RI and independently hydrogen or methyl, provided RI and R2 are not both hydrogen; x + y is equal to 8, 9 or 10 and z is at least 2.
Preferred detergent compositions according to the present invention, for example one useful for laundering fabrics, comprise from about 0.001% to about 99% of a mixture of mid-chain branched primary alkyl polyoxyalkylene surfactants, said mixture comprising at least about 5 % by weight of one or more mid-chain branched alkyl polyoxyalkylenes having the formula:

CH3 (CHZ)aCH (CH2~CH2 (EO/PO)mOH
(I) CH3 (CHy)dCH (CH2)e CH CHZ (EO/PO)mOH
(II) or mixtures thereof; wherein a, b, d, and a are integers, a+b is from 10 to 16, d+e is from 8 to 14 and wherein further when a + b = 10, a is an integer from 2 to 9 and b is an integer from 1 to 8;
when a + b = 11, a is an integer from 2 to 10 and b is an integer from 1 to 9;
when a + b = 12, a is an integer from 2 to 11 and b is an integer from 1 to 10;
when a + b = 13, a is an integer from 2 to 12 and b is an integer from 1 to 11;
when a + b = 14, a is an integer from 2 to 13 and b is an integer from 1 to 12;
when a + b = 15, a is an integer from 2 to 14 and b is an integer from I to 13;
when a + b = 16, a is an integer from 2 to I 5 and b is an integer from 1 to 14;
when d + a = 8, d is an integer from 2 to 7 and a is an integer from 1 to 6;
when d + a = 9, d is an integer from 2 to 8 and a is an integer from i to 7;
when d + a = 10, d is an integer from 2 to 9 and a is an integer from 1 to 8;
when d + a = 11, d is an integer from 2 to 10 and a is an integer from 1 to 9;
when d + a = 12, d is an integer from 2 to 1 I and a is an integer from 1 to 10;
when d + a = 13, d is an integer from 2 to 12 and a is an integer from 1 to 11;
when d + a = 14, d is an integer from 2 to 13 and a is an integer from 1 to 12;
and wherein further for this surfactant mixture the average total number of carbon atoms in the branched primary alkyl moieties having the above formulas is within the range of greater than 14.5 to about 17.5; and EO/PO are alkoxy moieties selected from ethoxy, propoxy, and mixed ethoxy/propoxy groups, wherein m is at least about 1, preferably within the range of from about 3 to about 30, more preferably from about S to about 20, and most preferably from about S to about IS.
Further, the present invention surfactant composition may comprise a mixture of branched primary alkyl polyoxyalkylenes having the formula R Rl R2 CH3CH2(CH2)~,CH(CH2}xCH(CH2h,CH(CH2)Z{EO/PO)mOH
wherein the total number of carbon atoms per molecule, including branching, is from 14 to 20, and wherein further for this surfactant mixture the average total number of carbon atoms in the branched primary alkyl moieties having the above formula is within the range of greater than 14.5 to about 17.5; R, R1, and R2 are each independently selected from hydrogen and C1-C3 alkyl, provided R, R1, and R2 are not all hydrogen; w is an integer from 0 to 13; x is an integer from 0 to 13; y is an integer from 0 to 13; z is an integer of at least 1; w + x + y + z is from 8 to 14; EO/PO are alkoxy moieties, preferably selected from ethoxy, propoxy, and mixed ethoxy/propoxy groups, wherein m is at least about I, preferably within the range of from about 3 to about 30, more preferably from about S to about 20, and most preferably from about S to about 1 S; provided that when R2 is C I-C3 alkyl the ratio of surfactants having z equal to 2 or greater to surfactants having z of 1 is at least about 1:1, preferably at least about 1.5:1, more preferably at least about 3:1, and most preferably at least about 4:1. Also preferred are surfactant compositions when R2 is C1-C3 alkyl comprising less than about SO%, preferably less than about 40%, more preferably less than about 2S%, most preferably less than about 20%, of branched primary alkyl polyoxyalkylene having the above formula wherein z equals 1.
Preferred mono-methyl branched primary alkyl ethoxylates are selected from the group consisting of 3-methyl pentadecanol ethoxylate, 4-methyl pentadecanol ethoxylate, S-methyl pentadecanol ethoxylate, 6-methyl pentadecanol ethoxylate, 7-methyl pentadecanol ethoxylate, 8-methyl pentadecanol ethoxylate, 9-methyl pentadecanol ethoxylate, 10-methyl pentadecanol ethoxylate, 1 I-methyl pentadecanol ethoxylate, 12-methyl pentadecanol ethoxylate, 13-methyl pentadecanol ethoxylate, 3-methyl hexadecanol ethoxylate, 4-methyl hexadecanol ethoxylate, S-methyl hexadecanol ethoxylate, 6-methyl hexadecanol ethoxylate, 7-methyl hexadecanol ethoxylate, 8-methyl hexadecanol ethoxylate, 9-methyl hexadecanol ethoxylate, 10-methyl hexadecanol ethoxylate, I 1-methyl hexadecanol ethoxylate, 12-methyl hexadecanol ethoxylate, 13-methyl hexadecanol ethoxylate, 14-methyl hexadecanol ethoxylate, and mixtures thereof, wherein the compounds are ethoxylated with an average degree of ethoxylation of from about S to about 1S.

WO 99/19453 PCT/US9$/21420 Preferred di-methyl branched primary alkyl ethoxylates selected from the group consisting of: 2,3-methyl tetradecanol ethoxylate, 2,4-methyl tetradecanol ethoxylate, 2,5-methyl tetradecanol ethoxylate, 2,6-methyl tetradecanol ethoxylate, 2,7-methyl tetradecanol ethoxylate, 2,8-methyl tetradecanol ethoxylate, 2,9-methyl tetradecanol ethoxyiate, 2,10-methyl tetradecanol ethoxylate, 2,11-methyl tetradecanol ethoxylate, 2,12-methyl tetradecanoi ethoxylate, 2,3-methyl pentadecanol ethoxylate, 2,4-methyl pentadecanol ethoxylate, 2,5-methyl pentadecanol ethoxylate, 2,6-methyl pentadecanol ethoxylate, 2,7-methyl pentadecanoi ethoxylate, 2,8-methyl pentadecanol ethoxylate, 2,9-methyl pentadecanol ethoxylate, 2,10-methyl pentadecanol ethoxylate, 2,11-methyl pentadecanol ethoxylate, 2,12-methyl pentadecanol ethoxylate, 2,13-methyl pentadecanol ethoxylate, and mixtures thereof, wherein the compounds are ethoxylated with an average degree of ethoxylation of from about 5 to about I5.
(31 Mid-chain Branched Primy Alkyl Alko~ylated Sulfate Surfactants The present invention branched surfactant compositions may comprise one or more (preferably a mixture of two or more) mid-chain branched primary alkyl alkoxylated sulfates having the formula:

CH3CH2(CH2)~,CH(CH2~CH(CH2)yCH(CH2)Z(EO/PO)m0 S03M
The surfactant mixtures of the present invention comprise molecules having a linear primary alkoxylated sulfate chain backbone (i.e., the longest linear carbon chain which includes the alkoxy-sulfated carbon atom). These alkyl chain backbones comprise from 12 to 19 carbon atoms; and further the molecules comprise a branched primary alkyl moiety having at least a total of 14, but not more than 20, carbon atoms. In addition, the surfactant mixture has an average total number of carbon atoms for the branched primary alkyl moieties within the range of from greater than 14.5 to about 17.5. Thus, the present invention mixtures comprise at least one alkoxyiated sulfate compound having a longest linear carbon chain of not less than 12 carbon atoms or more than 19 carbon atoms, and the total number of carbon atoms including branching must be at least 14, and further the average total number of carbon atoms for the branched primary alkyl chains is within the range of greater than 14.5 to about 17.5.
For example, a C 16 total carbon (in the alkyl chain) primary alkyl alkoxylated sulfate surfactant having 15 carbon atoms in the backbone must have a methyl branching unit (either R, RI or R2 is methyl) whereby the total number of carbon atoms in the primary alkyl moiety of the molecule is i6.

R, R1, and R2 are each independently selected from hydrogen and C1-C3 alkyl (preferably hydrogen or C1-C2 alkyl, more preferably hydrogen or methyl, and most preferably methyl), provided R, R1, and RZ are not all hydrogen. Further, when z is 1, at least R or R1 is not hydrogen.
Although for the purposes of the present invention surfactant compositions the above formula does not include molecules wherein the units R, R1, and R2 are all hydrogen (i.e., linear non-branched primary alkoxylated sulfates), it is to be recognized that the present invention compositions may still further comprise some amount of linear, non-branched primary alkoxylated sulfate. Further, this linear non-branched primary alkoxylated sulfate surfactant may be present as the result of the process used to manufacture the surfactant mixture having the requisite mid-chain branched primary alkoxylated sulfates according to the present invention, or for purposes of formulating detergent compositions some amount of linear non-branched primary alkoxylated sulfate may be admixed into the final product formulation.
It is also to be recognized that some amount of mid-chain branched alkyl sulfate may be present in the compositions. This is typically the result of sulfation of non-alkoxylated alcohol remaining following incomplete aikoxylation of the mid-chain branched alcohol used to prepare the alkoxylated sulfate useful herein. It is to be recognized, however, that separate addition of such mid-chain branched alkyl sulfates is also contemplated by the present invention compositions.
Further it is to be similarly recognized that non-sulfated mid-chain branched alcohol (including polyoxyalkylene alcohols) may comprise some amount of the present invention alkoxylated sulfate-containing compositions. Such materials may be present as the result of incomplete sulfation of the alcohol (alkoxylated or non-alkoxylated) used to prepare the alkoxylated sulfate surfactant, or these alcohols may be separately added to the present invention detergent compositions along with a mid-chain branched alkoxylated sulfate surfactant according to the present invention.
M is as described hereinbefore.
Further regarding the above formula, w is an integer from 0 to 13; x is an integer from 0 to 13; y is an integer from 0 to 13; z is an integer of at least 1; and w + x + y + z is an integer from 8 to 14.
EO/PO are alkoxy moieties, preferably selected from ethoxy, propoxy, and mixed ethoxy/propoxy groups, wherein m is at least about 0.01, preferably within the range of from about 0.1 to about 30, more preferably from about 0.5 to about 10, and most preferably from about 1 to about 5. The (EO/PO)m moiety may be either a distribution with average degree of alkoxylation (e.g., ethoxylation and/or propoxylation) corresponding to m, or it may be a single specific chain with alkoxylation (e.g., ethoxylation and/or propoxylation) of exactly the number of units corresponding to m.
The preferred surfactant mixtures of the present invention have at least 0.001 %, more preferably at least 5%, most preferably at least 20% by weight, of the mixture one or more mid-chain branched primary alkyl alkoxylated sulfates having the formula I I
CH3CH2(CH2)xCH(CH2h,CH(CH2)z(EO/PO)m0 S03M
wherein the total number of carbon atoms, including branching, is from 15 to 18, and wherein further for this surfactant mixture the average total number of carbon atoms in the branched primary alkyl moieties having the above formula is within the range of greater than 14.5 to about 17.5; R 1 and R2 are each independently hydrogen or C 1-C3 alkyl; M is a water soluble cation; x is from 0 to 11; y is from 0 to 11; z is at least 2;
and x + y + z is from 9 to 13; provided R1 and R2 are not both hydrogen; and EO/PO are alkoxy moieties selected from ethoxy, propoxy, and mixed ethoxy/propoxy groups, wherein m is at least about 0.01, preferably within the range of from about 0.1 to about 30, more preferably from about 0.5 to about 10, and most preferably from about 1 to about 5. More preferred are compositions having at least 5% of the mixture comprising one or more mid-chain branched primary alkoxylated sulfates wherein z is at least 2.
Preferably, the mixtures of surfactant comprise at least 5%, preferably at least about 20%, of a mid chain branched primary alkyl alkoxylated sulfate having R1 and R2 independently hydrogen or methyl, provided R1 and R2 are not both hydrogen; x + y is equal to 8, 9 or 10 and z is at least 2.
Preferred detergent compositions according to the present invention, for example one useful for laundering fabrics, comprise from about 0.001% to about 99% of a mixture of mid-chain branched primary alkyl alkoxylated sulfate surfactants, said mixture comprising at least about 5 % by weight of one or more mid-chain branched alkyl alkoxylated sulfates having the formula:

CH3 (CH2)aCH (CHZ~CH2 (EO/PO)m0 SO3M
(I) -CH3 (CH2)dCH (CH2)e CH CH2 (EO/PO)m0 SO3M
(II) or mixtures thereof; wherein M represents one or more cations; a, b, d, and a are integers, a+b is from 10 to 16, d+e is from 8 to 14 and wherein further when a + b = 10, a is an integer from 2 to 9 and b is an integer from 1 to 8;
when a + b = I 1, a is an integer from 2 to 10 and b is an integer from I to 9;

when a + b = 12, a is an integer from 2 to 11 and b is an integer from 1 to 10;
when a + b = 13, a is an integer from 2 to 12 and b is an integer from 1 to I
1;
when a + b = 14, a is an integer from 2 to 13 and b is an integer from 1 to 12;
when a + b = 15, a is an integer from 2 to 14 and b is an integer from I to 13;
when a + b = 16, a is an integer from 2 to 15 and b is an integer from 1 to 14;
when d + a = 8, d is an integer from 2 to 7 and a is an integer from 1 to 6;
when d + a = 9, d is an integer from 2 to 8 and a is an integer from 1 to 7;
when d + a = 10, d is an integer from 2 to 9 and a is an integer from 1 to 8;
when d + a = 11, d is an integer from 2 to 10 and a is an integer from 1 to 9;
when d + a = 12, d is an integer from 2 to 11 and a is an integer from 1 to 10;
when d + a = 13, d is an integer from 2 to 12 and a is an integer from 1 to 11;
when d + a = 14, d is an integer from 2 to 13 and a is an integer from 1 to 12;
and wherein further for this surfactant mixture the average total number of carbon atoms in the branched primary alkyl moieties having the above formulas is within the range of greater than 14.5 to about 17.5; and EO/PO are alkoxy moieties selected from ethoxy, propoxy, and mixed ethoxy/propoxy groups, wherein m is at least about 0.01, preferably within the range of from about 0.1 to about 30, more preferably from about 0.5 to about 10, and most preferably from about 1 to about 5.
Further, the present invention surfactant composition may comprise a mixture of branched primary alkyl alkoxylated sulfates having the formula CH3CH2(CH2)ryCH(CHZ~CH(CH2h,CH(CH2~(EO/PO)m0 S03M
wherein the total number of carbon atoms per molecule, including branching, is from 14 to 20, and wherein further for this surfactant mixture the average total number of carbon atoms in the branched primary alkyl moieties having the above fonmula is within the range of greater than 14.5 to about 17.5; R, RI, and R2 are each independently selected fram hydrogen and C1-C3 alkyl, provided R, R1, and R2 are not all hydrogen; M is a water soluble cation; w is an integer from 0 to 13; x is an integer from 0 to 13; y is an integer from 0 to 13; z is an integer of at least 1; w + x + y + z is from 8 to 14;
EO/PO are alkoxy moieties, preferably selected from ethoxy, propoxy, and mixed ethoxy/propoxy groups, wherein m is at least about 0.01, preferably within the range of from about 0.1 to about 30, more preferably from about 0.5 to about 10, and most preferably from about 1 to about 5;
provided that when R2 is C 1-C3 alkyl the ratio of surfactants having z equal to 2 or greater to surfactants having z of 1 is at least about I:I, preferably at least about 1.5:1, more preferably at least about 3:1, and most preferably at least about 4:1. Also preferred are surfactant compositions when R2 is C 1-C3 alkyl comprising less than about 50%, preferably less than about 40%, more preferably less than about 25%, most preferably less than about 20%, of branched primary alkyl alkoxylated sulfate having the above formula wherein z equals 1.
Preferred mono-methyl branched primary alkyl ethoxylated sulfates are selected from the group consisting of: 3-methyl pentadecanol ethoxylated sulfate, 4-methyl pentadecanol ethoxylated sulfate, 5-methyl pentadecanol ethoxylated sulfate, 6-methyl pentadecanol ethoxylated sulfate, 7-methyl pentadecanol ethoxylated sulfate, 8-methyl pentadecanol ethoxylated sulfate, 9-methyl pentadecanol ethoxylated sulfate, 10-methyl pentadecanol ethoxylated sulfate, 11-methyl pentadecanol ethoxylated sulfate, 12-methyl pentadecanol ethoxylated sulfate, 13-methyl pentadecanol ethoxylated sulfate, 3-methyl hexadecanol ethoxylated sulfate, 4-methyl hexadecanol ethoxylated sulfate, 5-methyl hexadecanol ethoxylated sulfate, 6-methyl hexadecanol ethoxylated sulfate, 7-methyl hexadecanol ethoxylated sulfate, 8-methyl hexadecanol ethoxylated sulfate, 9-methyl hexadecanol ethoxylated sulfate, 10-methyl hexadecanol ethoxylated sulfate, 11-methyl hexadecanol ethoxylated sulfate, 12-methyl hexadecanol ethoxylated sulfate, 13-methyl hexadecanol ethoxylated sulfate, 14-methyl hexadecanol ethoxylated sulfate, and mixtures thereof, wherein the compounds are ethoxylated with an average degree of ethoxylation of from about 0.1 to about 10.
Preferred di-methyl branched primary alkyl ethoxylated sulfates selected from the group consisting of: 2,3-methyl tetradecanol ethoxylated sulfate, 2,4-methyl tetradecanol ethoxylated sulfate, 2,5-methyl tetradecanol ethoxylated sulfate, 2,6-methyl tetradecanol ethoxylated sulfate, 2,7-methyl tetradecanol ethoxylated sulfate, 2,8-methyl tetradecanol ethoxylated sulfate, 2,9-methyl tetradecanol ethoxylated sulfate, 2,10-methyl tetradecanol ethoxylated sulfate, 2,11-methyl tetradecanol ethoxylated sulfate, 2,12-methyl tetradecanol ethoxylated sulfate, 2,3-methyl pentadecanol ethoxylated sulfate, 2,4-methyl pentadecanol ethoxylated sulfate, 2,5-methyl pentadecanol ethoxylated sulfate, 2,6-methyl pentadecanol ethoxylated sulfate, 2,7-methyl pentadecanol ethoxylated sulfate, 2,8-methyl pentadecanol ethoxylated sulfate, 2,9-methyl pentadecanol ethoxylated sulfate, 2,10-methyl pentadecanol ethoxylated sulfate, 2,11-methyl pentadecanol ethoxylated sulfate, 2,12-methyl pentadecanol ethoxylated sulfate, 2,13-methyl pentadecanol ethoxylated sulfate, and mixtures thereof, wherein the compounds are ethoxylated with an average degree of ethoxylation of from about 0.1 to about 10.
The paste can include adjunct surfactants such as those selected from anionics other than BAS, nonionic, zwitterionic, ampholytic and cationic classes and compatible mixtures thereof. Detergent surfactants useful herein are described in U.S. Patent 3,664,961, Norris, issued May 23, 1972, and in U.S. Patent 3,919,678, Laughiin et al., issued December 30, 1975, both of which are incorporated herein by reference. Useful cationic surfactants also include those described in U.S. Patent 4,222,905, Cockrell, issued September 16, 1980, and in U.S. Patent 4,239,659, Murphy, issued December 16, 1980, both of which are also incorporated herein by reference.
The following are representative examples of adjunct detergent surfactants useful in the present surfactant paste. Water-soluble salts of the higher fatty acids, i.e., "soaps", are useful anionic surfactants in the compositions herein. This includes alkali metal soaps such as the sodium, potassium, ammonium, and alkylolammonium salts of higher fatty acids containing from about 8 to about 24 carbon atoms, and preferably from about 12 to about 18 carbon atoms. Soaps can be made by direct saponification of fats and oils or by the neutralization of free fatty acids. Particularly useful are the sodium and potassium salts of the mixtures of fatty acids derived from coconut oil and tallow, i.e., sodium or potassium tallow and coconut soap.
Additional anionic surfactants which suitable for use herein include the water-soluble salts, preferably the alkali metal, ammonium and alkylolammonium salts, of organic sulfuric reaction products having in their molecular structure a straight-chain alkyl group containing from about 10 to about 20 carbon atoms and a sulfonic acid or sulfuric acid ester group. (Included in the term "alkyl" is the alkyl portion of acyl groups.) Examples of this group of synthetic surfactants are the sodium and potassium alkyl sulfates, especially those obtained by sulfating the higher alcohols (C8-18 carbon atoms) such as those produced by reducing the glycerides of tallow or coconut oil; and the sodium and potassium alkylbenzene sulfonates in which the alkyl group contains from about 9 to about 15 carbon atoms, in straight chain, e.g., those of the type described in U.S.
Patents 2,220,099 and 2,477,383. Especially valuable are linear straight chain alkylbenzene sulfonates in which the average number of carbon atoms in the alkyl group is from about 11 to 13, abbreviated as C11-13 LAS.
Other anionic surfactants suitable for use herein are the sodium alkyl glyceryl ether sulfonates, especially those ethers of higher alcohols derived from tallow and coconut oil;
sodium coconut oil fatty acid monoglyceride sulfonates and sulfates; sodium or potassium of ethylene oxide per molecule and wherein the alkyl groups contain from about 8 to about 12 carbon atoms; and sodium or potassium salts of alkyl ethylene oxide ether sulfates containing about 1 to about 10 units of ethylene oxide per molecule and wherein the alkyl group contains from about 10 to about 20 carbon atoms.
In addition, suitable anionic surfactants include the water-soluble salts of esters of alpha-sulfonated fatty acids containing from about 6 to 20 carbon atoms in the fatty acid group and from about I to 10 carbon atoms in the ester group; water-soluble salts of 2-acyloxyalkane-1-sulfonic acids containing from about 2 to 9 carbon atoms in the acyl group and from about 9 to about 23 carbon atoms in the alkane moiety; alkyl ether sulfates containing from about 10 to 20 carbon atoms in the alkyl group and from about 1 to 30 moles of ethylene oxide; water-soluble salts of olefin and paraffin sulfonates containing from about 12 to 20 carbon atoms; and beta-alkyloxy alkane sulfonates containing from about 1 to 3 carbon atoms in the alkyl group and from about 8 to 20 carbon atoms in the alkane moiety.
Preferred adjunct anionic surfactants are C10-18 linear alkylbenzene sulfonate and CIO-18 alkyl sulfate. If desired, low moisture (less than about 25% water) alkyl sulfate paste can be the sole ingredient in the surfactant paste. Most preferred are CIO-18 alkyl sulfates, linear or branched, and any of primary, secondary or tertiary. A
preferred embodiment of the present invention is wherein the surfactant paste comprises from about 20% to about 40% of a mixture of sodium C10-13 linear alkylbenzene sulfonate and sodium C 12-16 alkyl sulfate in a weight ratio of about 2:1 to 1:2. Another preferred embodiment of the detergent composition includes a mixture of C 10-18 alkyl sulfate and C 10-18 alkyl ethoxy sulfate in a weight ratio of about 80:20.
Water-soluble nonionic surfactants are also useful in the instant invention.
Such nonionic materials include compounds produced by the condensation of alkylene oxide groups (hydrophilic in nature) with an organic hydrophobic compound, which may be aliphatic or alkyl aromatic in nature. The length of the polyoxyalkylene group which is condensed with any particular hydrophobic group can be readily adjusted to yield a water-soluble compound having the desired degree of balance between hydrophilic and hydrophobic elements.
Suitable nonionic surfactants include the polyethylene oxide condensates of alkyl phenols, e.g., the condensation products of alkyl phenols having an alkyl group containing from about 6 to 15 carbon atoms, in either a straight chain or branched chain configuration, with from about 3 to 12 moles of ethylene oxide per mole of alkyl phenol.
Included are the water-soluble and water-dispersible condensation products of aliphatic alcohols containing from 8 to 22 carbon atoms, in either straight chain or branched configuration, with from 3 to 12 moles of ethylene oxide per mole of alcohol.
An additional group of nonionics suitable for use herein are semi-polar nonionic surfactants which include water-soluble amine oxides containing one alkyl moiety of from abut 10 to 18 carbon atoms and two moieties selected from the group of alkyl and hydroxyalkyl moieties of from about 1 to about 3 carbon atoms; water-soluble phosphine oxides containing one alkyl moiety of about 10 to 18 carbon atoms and two moieties selected from the group consisting of alkyl groups and hydroxyalkyl groups containing from about 1 to 3 carbon atoms; and water-soluble sulfoxides containing one alkyl moiety of from about I 0 to 18 carbon atoms and a moiety selected from the group consisting of alkyl and hydroxyalkyl moieties of from about 1 to 3 carbon atoms.

Preferred nonionic surfactants are of the formula R1(OC2H4)nOH, wherein R1 is a C 1 ~ C 16 alkyl group or a Cg C 12 alkyl phenyl group, and n is from 3 to about 80.
Particularly preferred are condensation products of C 12 C 15 alcohols with from about 5 to about 20 moles of ethylene oxide per mole of alcohol, e.g., C 12 C 13 alcohol condensed with about 6.5 moles of ethylene oxide per mole of alcohol.
Additional suitable nonionic surfactants include polyhydroxy fatty acid amides.
Examples are N-methyl N-1-deoxyglucityl cocoamide and N-methyl N-I-deoxyglucityl oleamide. Processes for making polyhydroxy fatty acid amides are known and can be found in Wilson, U.S. Patent No. 2,965,576 and Schwartz, U.S. Patent No. 2,703,798, the disclosures of which are incorporated herein by, reference.
Ampholytic surfactants include derivatives of aliphatic or aliphatic derivatives of heterocyclic secondary and tertiary amines in which the aliphatic moiety can be straight chain or branched and wherein one of the aliphatic substituents contains from about 8 to 18 carbon atoms and at least one aliphatic substituent contains an anionic water-solubilizing group.
Zwitterionic surfactants include derivatives of aliphatic, quaternary, ammonium, phosphonium, and sulfonium compounds in which one of the aliphatic substituents contains from about 8 to 18 carbon atoms.
Cationic surfactants can also be included in the present invention. Cationic surfactants comprise a wide variety of compounds characterized by one or more organic hydrophobic groups in the cation and generally by a quaternary nitrogen associated with an acid radical. Pentavalent nitrogen ring compounds are also considered quaternary nitrogen compounds. Suitable anions are halides, methyl sulfate and hydroxide. Tertiary amines can have characteristics similar to cationic surfactants at washing solution pH values less than about 8.5. A more complete disclosure of these and other cationic surfactants useful herein can be found in U.S. Patent 4,228,044, Cambre, issued October 14, 1980, incorporated herein by reference.
Cationic surfactants are often used in detergent compositions to provide fabric softening and/or antistatic benefits. Antistatic agents which provide some softening benefit and which are preferred herein are the quaternary ammonium salts described in U.S. Patent 3,936,537, Baskerville, Jr. et al., issued February 3, 1976, the disclosure of which is incorporated herein by reference.
The compositions of the invention can contain all manner of organic, water-soluble detergent compounds, inasmuch as the builder material are compatible with all such materials. In addition to a detersive surfactant, at least one suitable adjunct detergent ingredient is preferably included in the detergent composition. The adjunct detergent ingredient is preferably selected from the group consisting of builders, enzymes, bleaching agents, bleach activators, suds suppressors, soil release agents, brighteners, perfumes, hydrotropes, dyes, pigments, polymeric dispersing agents, pH controlling agents, chelants, processing aids, crystallization aids, and mixtures thereof. The following list of detergent ingredients and mixtures thereof which can be used in the compositions herein is representative of the detergent ingredients, but is not intended to be limiting.
One or more builders can be used in conjunction with the builder material described herein to further improve the performance of the compositions described herein.
For example, the builder can be selected from the group consisting of aluminosilicates, crystalline layered silicates, MAP zeolites, citrates, amorphous silicates, polycarboxylates, sodium carbonates and mixtures thereof. The sodium carbonate ingredient can serve as the inorganic alkaline material when a liquid acid precursor of the mid-chain branched surfactant is used. Other suitable auxiliary builders are described hereinafter.
Preferred builders include aluminosilicate ion exchange materials and sodium carbonate. The aluminosilicate ion exchange materials used herein as a detergent builder preferably have both a high calcium ion exchange capacity and a high exchange rate.
Without intending to be limited by theory, it is believed that such high calcium ion exchange rate and capacity are a function of several interrelated factors which derive from the method by which the aluminosilicate ion exchange material is produced. In that regard, the aluminosilicate ion exchange materials used herein are preferably produced in accordance with Corkill et al, U.S. Patent No. 4,605,509 (Procter & Gamble), the disclosure of which is incorporated herein by reference.
Preferably, the aluminosilicate ion exchange material is in "sodium" form since the potassium and hydrogen forms of the instant aluminosilicate do not exhibit the as high of an exchange rate and capacity as provided by the sodium form. Additionally, the aluminosilicate ion exchange material preferably is in over dried form so as to facilitate production of crisp detergent agglomerates as described herein. The aiuminosilicate ion exchange materials used herein preferably have particle size diameters which optimize their effectiveness as detergent builders. The term "particle size diameter"
as used herein represents the average particle size diameter of a given aluminosilicate ion exchange material as determined by conventional analytical techniques, such as microscopic determination and scanning electron microscope (SEM). The preferred particle size diameter of the aluminosilicate is from about 0.1 micron to about 10 microns, more preferably from about 0.5 microns to about 9 microns. Most preferably, the particle size diameter is from about 1 microns to about 8 microns.
Preferably, the aluminosilicate ion exchange material has the formula Naz~(A102)z.(Si02)y]xH20 wherein z and y are integers of at least 6, the molar ratio of z to y is from about 1 to about and x is from about 10 to about 264. More preferably, the aluminosilicate has the formula Nal2[(A102)12~(Si02)12~~20 wherein x is from about 20 to about 30, preferably about 27. These preferred aluminosilicates are available commercially, for example under designations ZeoIite A, Zeolite B and Zeolite X. Alternatively, naturally-occurring or synthetically derived aluminosilicate ion exchange materials suitable for use herein can be made as described in Krummel et al, U.S. Patent No. 3,985,669, the disclosure of which is incorporated herein by reference.
The aluminosilicates used herein are further characterized by their ion exchange capacity which is at least about 200 mg equivalent of CaC03 hardness/gram, calculated on an anhydrous basis, and which is preferably in a range from about 300 to 352 mg equivalent of CaC03 hardness/gram. Additionally, the instant aluminosilicate ion exchange materials are still further characterized by their calcium ion exchange rate which is at least about 2 grains Cap-'~'/gallon/minute/-gram/gallon, and more preferably in a range from about 2 grains Ca'~'~/gallon/minute/-gram/gallon to about 6 grains Ca'~-~-/gallon/minute/-gram/gallon .
In order to make the present invention more readily understood, reference is made to the following examples, which are intended to be illustrative only and not intended to be limiting in scope.
EXAMPLE
This Example illustrates the process of the invention which produces free flowing, crisp, high density detergent composition. Two feed streams of various detergent starting ingredients including a surfactant paste containing the mid-chain branched surfactant and water and the other stream containing starting dry detergent material containing aluminosilicate and sodium carbonate are fed to a crutcher for continuous mixing, thus forming a slurry. The slurry is fed to a conventional spray drying process in which the slurry is passed though a spray drying tower having a counter current stream of hot air (200-300°C) resulting in the formation of porous spray dried granules having a density of about 250 g/l. The spray dried granules are sent to a compactor (commercially available from the Sahut Company) which form compacted granules having a density of about 1300 g/l. Subsequently and continuously, the compacted granules are sent to a grinder to form ground detergent particles having a density of about 700 g/l. The ground detergent particles, excluding oversized ground particles which recycled back to the grinder, are fed to the first of four serially positioned moderate speed mixers. Each of the moderate speed mixers are Lodige KM-600 mixers in which aluminosilicate is added to coat the ground detergent particles resulting in a high density detergent composition having a density of 800 g/l. Admixed ingredients are added as the high density detergent composition is passed through a vertical mixer such as a Fukae mixer. The final composition of the high density detergent composition produced by the process is given below:
u~°
Base Granule 016.5 alkyl sulfate (mid-chain 14.1 branched), Na Aluminosilicate 2,g Sodium carbonate 16.6 C12-13 linear alkylbenzene sulfonate,4.2 Na C14-15 alkyl sulfate, Na 9.9 Sodium silicate 12.0 Brightener 491 0.2 Brightener 1 0.1 Copolymer of Malefic and Acrylic 7.0 Acid Co tinQ

~ 3.3 C 12-15 alkyl ethoxylate (EO =
7) Aluminosilicate 6.7 Sodium silicate 0.3 Silica 0.2 Meltose 0.3 Perfume 0.1 Perfume 0.3 Soil Release Polymer 2 0.3 Protease (40mg/g)3 0.2 NOBS 4 3.8 Sodium Perborate 3.5 Polydimethylsiloxane 2.0 Crystalline layered silicate 7.6 Miscellaneous (water, etc.) ]dance Total 100.0 1 Purchased from Ciba-Geigy 2Made according to U.S. Patent 5,415,807, issued May 16, 1995 to Gosselink et al 3 Purchased from Genencor 4 Nonanoyloxybenzenesulfonate, Na Having thus described the invention in detail, it will be clear to those skilled in the art that various changes may be made without departing from the scope of the invention and the invention is not to be considered limited to what is described in the specification.

Claims

What is claimed is:

1. A process for continuously preparing a high density detergent composition characterized by the steps of:
(A) continuously mixing a detergent surfactant paste and dry starting detergent material into a mixer to obtain a slurry, said surfactant paste containing mid-chain branched surfactant compounds of the formula:
A b-X-B
wherein:
(a) A b is a hydrophobic C9 to C22, total carbons in the moiety, preferably from C12 to C18, mid-chain branched alkyl moiety having: (1) a longest linear carbon chain attached to the -X- B moiety in the range of from 8 to 21 carbon atoms; (2) one or more C1 - C3 alkyl moieties branching from this longest linear carbon chain; (3) at least one of the branching alkyl moieties is attached directly to a carbon of the longest linear carbon chain at a position within the range of position 2 carbon, counting from carbon # 1 which is attached to the -X- B moiety, to position .omega. - 2 carbon, the terminal carbon minus 2 carbons; and (4) the surfactant composition has an average total number of carbon atoms in the A b-X moiety in the above formula within the range of greater than 14.5 to 18;
(b) B is a hydophilic moiety selected from sulfates, sulfonates, amine oxides, polyoxyalkylene, alkoxylated sulfates, polyhydroxy moieties, phosphate esters, glycerol sulfonates, polygluconates, polyphosphate esters, phosphonates, sulfosuccinates, sulfosuccaminates, polyalkoxylated carboxylates, glucamides, taurinates, sarcosinates, glycinates, isethionates, dialkanolamides, monoalkanolamides, monoalkanolamide sulfates, diglycolamides, diglycolamide sulfates, glycerol esters, glycerol ester sulfates, glycerol ethers, glycerol ether sulfates, polyglycerol ethers, polyglycerol ether sulfates, sorbitan esters, polyalkoxylated sorbitan esters, ammonioalkanesulfonates, amidopropyl betaines, alkylated quats, alkyated/polyhydroxyalkylated quats, alkylated quats, alkylated/polyhydroxylated oxypropyl quats, imidazolines, 2-yl-succinates, sulfonated alkyl esters, and sulfonated fatty acids; and (c) X is -CH2-;
(B) spray drying said slurry to for spray dried granules;
(C) compacting said spray dried granules in a compactor to form compacted granules;
(D) grinding said compacted granules to form ground detergent particles; and (E) coating said detergent particles with a coating agent, thereby forming said high density detergent composition.

2. A process according to claim 1 wherein the A b moiety is a branched primary alkyl moiety having the formula:
wherein the total number of carbon atoms in the branched primary alkyl moiety of this formula, including the R, R1, and R2 branching, is from 13 to 19; R, R1, and R2 are each independently selected from hydrogen and C1-C3 alkyl, preferably methyl, provided R, R1, and R2 are not all hydrogen and, when z is 0, at least R or R1 is not hydrogen; w is an integer from 0 to 13; x is an integer from 0 to 13; y is an integer from 0 to 13; z is an integer from 0 to 13; and w + x + y + z is from 7 to 13.

3. A process according to claim 1 wherein said coating step occurs in four serially positioned mixers.

4. A process according to claim 1 wherein said dry starting detergent material is selected from the group consisting of aluminosilicates, silicates, carbonates and mixtures thereof.

5. A process according to claim 1 wherein said surfactant paste further comprises linear alkylbenzene sulfonate and linear alkyl sulfate surfactants.

6. A process according to claim 1 further characterizing the step of recycling oversized ground detergent particles back to said grinding step, said oversized ground detergent particles having a median particle size of at least 1150 microns.

7. A process according to claim 1 wherein said coating agent is selected from the group consisting of aluminosilicates, carbonates, silicates, and mixtures thereof.

8. A process according to claim 1 further characterizing the step of admixing adjunct detergent ingredients to said high density detergent composition after said coating step.

9. A process according to claim 8 wherein said adjunct detergent ingredients are selected from the group consisting of enzymes, detergent builders, bleaching agents, bleach activators, dyes, soil release agents, and mixtures thereof.

10. A high density detergent product made according to claim 1.