CA1272658A

CA1272658A - Viscous phase stable liquid scouring cleansers containing solvent

Info

Publication number: CA1272658A
Application number: CA000518795A
Authority: CA
Inventors: Stephen H. Iding
Original assignee: Procter and Gamble Co
Current assignee: Procter and Gamble Co
Priority date: 1985-09-24
Filing date: 1986-09-23
Publication date: 1990-08-14
Also published as: GB2180847B; GB8622761D0; MA20773A1; AU6305386A; DK456486D0; SG47992G; HK48092A; EP0216416A3; AU604648B2; GB2180847A; FI863854A; DK456486A; EP0216416A2; GR862393B; FI863854A0

Abstract

IMPROVED VISCOUS PHASE STABLE
LIQUID SCOURING CLEANSERS CONTAINING SOLVENT

ABSTRACT
Improved phase stable liquid compositions, particularly for use as hard surface cleansers, comprise a mixture of sodium C12-C18 paraffin sulfonate (NaPS) and sodium salt of linear alkyl benzene sulfonate (LAS), terpenes, benzyl alcohol, acrylic acid polymeric thickeners, abrasives and viscosity enhancer com-pounds. The compositions are viscous, substantially phase stable and provide excellent cleaning of both greasy and particulate soils from hard surfaces without streaking or filming.

Description

2~8 IMPROVED VISCOUS PHASE STABLE
LIQUID SCOURING CLEANSERS CONTAINING SOLVENT

Stephen H. Iding TECHNICAL FIELD
This invention relates to liquid scouring cleansers. In particular, it relates to viscous, aqueous scouring cleansers containing an abrasive and a binary solvent system. These 10 cleansers are suitable for use as general purpose household cleaning compositions.
BACKG~OUND
General purpose household cleaning compositions for hard surfaces such as metal, glass, ceramic, plastic and linoleum 15 surfaces, are commercialiy available in both powdered and liquid form. Powdered cleaning compositions consist mainly of builder or buffering salts such as phosphates, carbonates, silicates, etc., and although such cornpositions may display good inorganic soil removal, they are generally deficient in cleaning ability on 20 organic soils such as the grease/fatty/oily soils typically found in the domestic environment.
Liquid cleaning compositions, on the other hand, have the great advantage that they can be applied to hard surfaces in neat or concentrated form so that a relatively high level of surfactant 25 material is delivered directly to the soil. Moreover, it is a rather more straightforward task to incorporate high concentrations of anionic or nonionic surfactant in a liquid rather than a granular composition. For both these reasons, therefore, liquid cleaning compositions have the potential to provide superior grease and 30 oily soil removal over powdered cleaning compositions.
Nevertheless, liquid cleaning compositions still suffer a number of drav~lbacks ~hich can limit their consumer a~cceptability.
Thus, they generally contain little or no detergency builder salts and consequently they tend to have poor cleaning per~ormance on 35 particulate soil and also lack "robustness" under v3rying water ~, -~27~

hardness levels. In addition, they can suffer problems of product form, in particular, phase instability, inhomogeneity, lack of clarity, or inadequate viscosity characteristics for consumer use. Moreover, the higher in-product and in-use surfactant concentration necessary for improved grease handling raises problems of extensive suds formation requiring frequent rinsing and wiping on behalf of the consumer, Although oversudsing may be controlled to some extent by incorporating a suds-regulating material such as hydrophobic silica and/or silicone or soap, this in itself can raise problems of poor product stability and homo-geneity and also problems associated with deposition of insoluble particulate or soap residues on the items or surfaces being cleaned, leading to filming, streaking and spotting.
Importantly, liquid cleaners suffer from the disadvantage that they do not contain abrasives, which contribute substantially to the cleaning performance of many dry-powder household and industrial cleaning compositions, Liquid cleansers that do contain abrasives can suffer from phase instability including layering and abrasive settling. This phase instability problem is aggravated when solvents are present in the cleanser compositions.
Terpenes are, per se, well-known components of perfume compositions and are often incorporated into detergent compo-sitions at low levels via the perfume. Certain terpenes have also been included in detergent compositions at higher levels; for instance, German Patent Application 21 13 732 discloses the use of aliphatic and alicyclic terpenes as antimicrobial agents in washing compositions; British Pat. No. 1,308,190 teaches the use of dipenten~s in a thixotropic liquid detergent suspension base composition. German Patant Applica~ion 29 09 690 teaches the use of pine oil (a mixture mainly of terpene aicohols) in ~iquid hard surface cleaning compositions.
European Application 81~200540.3 teaches the use~ of terpenes with solvents such as benzyl alcohol and ethylene glycol dibutyl ether in liquid cleanser compositions. European Application ~2-201396.7 teaches the use of terpenes and butyl"Carbitol"(a .: .

~;26~8 trademark for 2-(2-butoxyethoxy)ethanol) in a liquid cleanser, optionally with particulate zeolite builders.
! lowever, the use of the combination of selected terpenes, polar solvents, selected surfactant mixture, abrasive with poly-5 meric acrylic acid thickeners and viscosity enhancers disclosedherein does not appear to have been considered, heretofore.
SUMh/lARY OF THE INVENTION
.
The compositions herein may be succinctly described as viscous, phase stable liguid scouring cleansers which comprise 10 1-10% of a surfactant mixture of paraffin sulfonate ( NaPS) and alkyl benzene sulfonate (LAS), 0.5-10% of a terpen~ or a terpene derivative, or mixtures thereof; 0. 5-3% of a polar solvent (benzyl alcohol ) 0 . 4-1% of a high molecular weight acrylic polymeric thickener; and from 1-50% of a water-insoluble abrasive of the type described hereinafter; and 0.03-0.596 of selected viscosity enhancing compounds.
DETAILED DESCRIPTION OF THE INVENTION
The essential terpene, benzyl alcohol, abrasive, thickener, selected surfactant components, and other ingredients used in the practice of the present invention are described in more detail, hereinafter. All percentages and ratios mentioned in this speci-fication are by weight, unless otherwise stated.
It has now been discovered, however, that the defects of prior art liquid cleansers can be minimized or overcome through th¢ incorporation therein of a specified mixture of surfactants, acrylic acid polymeric thickeners, and selected terpenes, viscosity enhancers of the alcohol, nitrile, ketone and aldehyde classes as defined ~erein, in combination with benzyl alcohol, and with an abrasive.
The present invention provides abrasive-containing iiquid cleaning and scouring compositions which have ~xcellent phase stability and suds control across a broad range o~ usage and water hardness conditions and which provide excellent shine performance together with improved cleaning characteristics both on greasy/oily soils and on inorganic particulate soils, with little tendency to cause filming or streaking on washed surfaces.
Importantly, the abrasives used herein are soft, preferably 7~G~8 having a Mohs hardness of 3 or less.
Terpenes - Terpenes, as a solvent class, have limited water-solubility. They can be incorporated into liquid cleaning com-positions in homogeneous form, even under "cold" processing 5 conditions, with the ability to provide excellent cleaning char-acteristics across the range of water hardness on grease/oily soils and inorganic particulate soils, as well as on shoe polish, marker ink, bath tub soil, etc., and excellent shine performance with low soil redeposition and little or no propensity to cause filming, 10 streaking or spotting on surfaces washed therewith. Moreover, the terpenes herein specified, and in particular those o~ the hydrocarbon class, are valuable in regulating the sudsing be-ha~/ior of the instant compositions in both hard and soft water and under both diluted and neat or concentrated usage.
Preferred terpenes for odor impact are mono-and bicyclic monoterpenes, especially th~se of the hydrocarbon class, which include the terpinenes, terpinolenes, limonenes and pinenes, and mixtures thereof. Highly preferred materials of this type are d-limonene, dipentene, alpha-pinene, beta-pinene and the mixture 20 of terpene hydrocarbons obtained from the essence of citrus (e.g., cold-pressed orange terpenes and orange terpene oil phase ex fruit juice). These terpenes are used at c~ncentrations of at least 0 .1~, preferably 0 . 5%-5%, most preferably 1-3%, in the compositions ~or fragrance and cleaning effects. The weight ratio 25 of surfactant:terpene preferably is between 2û:1 and 3:2, more preferably 4 :1 to 1 . 5 :1.
Viscosity Enhancers - As mentioned hereinbefore, a special problem for thickened liquid scouring cleansers is achieving a stable, high viscosity p;oduct. It has been surprisingly dis-30 covered that certain alcohol, aldehyde, nitrile, acetate and ketonecompounds having VE empirical formulas of CnHmR where n = 10 ; or 12; m = 14, 16, 17, 18 or 20 and R = , 2 or.N, are vis-cosity enhancers (VE) when used in conj~Jnction with the high molecular weight acrylic acid polymeric thickeners. Some pre-35 ferred VE compounds are selected from citronellol, geraniol, linalool, nerol, rhodinal, alpha-terpineol, beta-citroneilol, rho-dinol, citronella nitrile, carvone, fenchone, menthol, isoborneol g~2~726513 and mixtures thereof. These preferred VE compounds are com-mercially ~vailable. These VE compounds are used in the compo-sitions of this invention at concentrations of from about 0.03% to about 0.5%, more preferably from about 0.05% to about 0.25%.
Polar Solvent - The polar solvent of this invention has a water solubility at 25C in the range of from about 0.2% to about 10% and is used at a level of from about 0 . 5% to about 3% .
Benzyl alcohol (C61 15CH2OH), the preferred polar solvent, is used in the compositions at concentrations of at least 0.1%, preferably 0~5~3~ most preferably 1-2~. This polar solvent increases the cleaning power of the compositions.
The weight ratio of terpenes to benzyl alcohol is preferably in the range from 5 1 to 1:5, most preferably 2:1 to 1:2.
- Abrasive - The abrasive is used at a level of 1-50% (prefer-_ ably 5~40%; most preferably 10-35%)o The abrasives employed herein are selected from water-insoluble, mild abrasive materials.
It is highly preferred that the abrasives used herein not be undesirably "scratchy." Abrasive materials having a Mohs hard-ness in the range of about 7, or below, are typically used;
abrasives having a Mohs hardness of 3, or below, can be used to avoid scratches on aluminum or stainless steel flnishes. Suitable abrasives herein include inorganic materials, especially such preferred materials as calcium carbonate and diatomaceous earth, as well as materials such as Fuller's earth, magnesium carbonate, China clay, attapulgite, calcium hydroxyapatite, calcium ortho-phosphate, dolomite and the like. Organic abrasives such as urea-formaldehyde, polyvinyl chloride, methyl methacrylate and melamine-formaldehyde resins can also be used, preferably at a level of 5-15%. The organic abrasives are more compatible with detergency builders and sequestrants.
It is preferred that the abrasives herein have a particle size ran~3e in the 100-600 U . S . Sieve Series Mesh, preferably 200-400 U . S . Sieve Series Mesh, size . Diatomaceous earth and calcium carbonate are commercially available in the 5-150 micron particle size range, and, as will ISe seen hereinafter, give excellent cleaning performance. The preferred abrasive is commercially available as Georgia Marble RO-4 Ground Calcium Carbonate.

Surfactants - The selected combination of NaPS and LAS has been found to provide superior phase stability in the cleansers of this invention. The selected water-soluble detersive surfactant useful herein is a mixture of linear alkyl benzene sulfonates (LAS) and paraffin sulfonates (NaPS). In general, such deter-sive surfactants contain an alkyl group in the C1 0-Cl 8 range; the selected surfactants are most commonly used in the form of their sodium, potassium or triethanolammonium salts. The C1 1-C16 alkyl benzene sulfonates and the C1 2 C1 8 paraffin sulfonates are 10 selected for the compositions of the present invention. As used herein, the abbreviations "LAS" and "NaPS" include these broader surfactant definitions, unless otherwise specified.
The compositions herein generally will con~ain about 1% to about 10%, preferably 2% to about 8%, more preferably 2 . 5-5%, of 15 the surfactant mixture. The mixture has a ratio of NaPS to LAS
of from 20 :1 to 2 :1, preferably 10 :1 to 2 :1, and more preferably from 7:1 ~o 4:1.
Thickeners - The selected thickeners of this invention are the high molecular weight polyacrylates which have molecular 20 weights of about 0.5-1.5 million with preferably some crosslinking of about 1-4%. Examples of suitable thickeners are (1) "Sokalan PHC-25" ex BASF; t2) "Acrysol ICS-1"** ex P~n and Haas (works best at high pH 11.9), and (3) "Carbopol 941"*** ex B.F. Goodrich.
"Carbopol 941"*** works well but leaves a film when rinsed after 25 product use. The thickeners of this invention are employed at 0.4-1%, preferably 0.45-0.75% by weight of the composition.
The compositions herein must be thickened for dispersion and phase stability at the 1800-4000 cps viscosity range. The compositions of this invention preferably have a viscosity in the 30 200û-3500 cps range, as measured with a standard Brookfield Viscometer. Thickened compositions tend to cling to vertical surfaces such as walls and windows, which makes them more convenient to use.
pH - The compositions herein are formulated in the alkaline 35 pH range, generally in the range of pH 8-12, preferably about 10-11. 5 to avoid hydrolysis of some perfume components. Caus-tics such as sodium hydroxide and sodium carbonate can be used : * Trade mark ** Trade mark ***Trade mark ~2~2G~8 to adjust and bu~fer the pH, as desired. An alkaline pH is also essential in obtaining the specified viscosity.
Soaps - As mentioned hereinabove, one special problem associated with the use of liquid cleansers is their tendency to 5 over-suds in use. It has been discovered that soaps, especially the alkali, ammonium and alkanolammonium salts of Cl 2-C2~ fatty acids, are especially useful as suds suppressors when conjointly present with terpenes and benzyl alcohol in the instant compo-sitions. Soap concentrations of at least about 0.005%, pref~rably 0.05% to 0.4%, provide this important suds control function. Soap prepared from coconut oil ~atty acids is preferred.
0ther Ing~ edients - The compositions herein can contain other ingredients which aid in their cleaning performance. Con-ventional additives such as detergency builders, water softeners, 1 5 carrier liquids (especially water), perfumes , and the like can be used. For example, it is highly pre~erred that the compositions with organic abrasives contain a detergent builder and/or metal ion sequestrant. Compounds classifiable and well known in the art as detergent builders include the nitrilotriacetates, poly-20 carboxylates, citrates, water-soluble phosphates such as tripoly-phosphate and sodium ortho- and pyrophosphates, silicates, and mixtures thereof. Metal ion sequestrants include all of the above, plus materials like ethylenediaminetetraacetate, the amino-poly-phosphonates and phosphates (DEQUEST*) and a wide variety of 25 other poly-functional organic acids and salts too nurnerous to mention in detail herein. See U.S. Pat. No. 3,579,454 for typical examples of the use of such materials in various cleaning compo-sitions. In general, the builder/sequestrant will comprise about 196 to about 25% of the composition. Colorants and perfumes can 30 be used with all abrasives.
Moreover, the compositions herein can contain, in addition to ingredients already mentioned, various optional ingr~edients typ-ically used in commercial products to provide aesthetic or addi-tional product performance benefits. Typical in~3redients include 35 perfumes, dyes, optical brighteners, soil suspending agents, detersive enzymes, gel-control agents, freeze-thaw stabilizers, *Trade mark :

~72G~

bactericides, preservatives, and the like. Nonionic surfactants at a level of 0.2-0.59~ are excellent freeze-thaw stabilizers.
The compositions herein typically contain up to about 90%
water as a carrier. Water-alcohol (e.g., ethanol, isopropanol, 5 butanol, etc. ) mixtures can also be used.
Since the compositions herein are in liquid form, they can be prepared by simply blending the essential and optional ingredients in the aqueous carrier.
The following examples are given by way of illustrating the 10 compositions herein, but are not intended to be limiting to the spirit and scope of the invention.

EXAMPL
Component Concentration in Cleans~r 1 5 Thickener "Sokalan PHC-25" 0 . 67%
Surfactants NaPS 3. 0%
LAS 0 . 6%
"Neodol 45-7" 0 . 30%
Solvent Benzyl Alcohol . 1 . 30%
Perfume Mix #l Citrus Terpenes 1.85%
Citrus Phase Oil 0.15%
Other Components 0.15%
Abrasive CaC,O3 (Avg . 50-60 microns) 30. 0%
Othe r Na~CO3 - 3 . 0%
Dye 0. 005%
NaOH 0 . 5%
Coconut/ Lauric Fatty Acid 0 . 2%
Water To Balance *Trade mark ~.z7~6~8 g Definitions NaPS : Sodium C13-C16 paraffin sulfonate LAS : Sodium salt of linear C11 8 alkyl benzene sulfonate Perfurne Mix #1: The "Other Components" of the perfume mix #1 contain 50-60% viscosity enhancing compounds of alcohol, nitrile and aldehyde of the C1oH20O
ClOH17N and C1~H18o formulas.
Neodol 45-7 : A condensate of one mole of C14-C15 fatty alcohol with 7 moles of ethylene oxide.
EXAMPLES 2 and 3 Impact of Terpenes on Product Viscosity Examples 2 and 3 were made in 2000 gram batches using a Lightening mixer. The ingredients were added in the order in 15 which they appear. A viscosity reading was recorded 5 minutes after each ingredient was added.
Example 2 Example 3 ~ FormulaViscosityFormulaViscosity Soft water 59.00% - 58.0096 Sokalan PHC-25 0.65%100 cps Acrysol ICS-1 - - 0.98%25 cps Anionic surfactant* 2 8% - 2.8%
Neodo, 45-7 0.5% 400 cps 0.5%50 cps Benzyl alcohol 1.5~ - 1.5~ -Lauric fatty acid 0.10% _ 0.10%
Coconut fatty acid 0.10% 25 cps0.10% 25 cps NaOH 0.25%550 cps 0.2596225 cps Na2CO3 - . % 250 cps 3.0096150 cps CaCO3 30.00%1250 cps30.00%1500 cps Perfume mix** 2.15%2750 cps 2 ~ 15%2700 cps *NaPS/LAS ratio 5:1.
**The perfume mix #1 comprises organic compounds which contain about 3-4 parts citronel,ol citronella nitrile and dihydro mercinol. This amount provides about 0.06-0.09% of viscosity enhancers by weight of the total composition.

~L27~

-- 1 o --Note in Examples 2 and 3 that the addition of the viscosity enhancing perfume mix had a profound impact on product vis-cosity. Without the perfume mix, the formulations would experi-ence abrasive settling and layering and have viscosities of only 1250and 1500 cps vs. 2750 and 2700 cps, respectively.

Impact of Selected Compounds on Product Viscosity Base Formula I
~ Wt. %
Soft water Balance Sokalan PHC-25 0.65 Anionic surfactant* 3,6 Neodol 45-7 o,50 Benzyl alcohol 1.3 Lauric fatty acid 0.1 Coconut fatty acid 0.1 NaOH 0.2 Na2C3 3.0 CaCO3 30.00 1~ 20 Colorant 0.01 Citrus terpenes 2.00 *NaPS/LAS ratio 5:1.

Selected Compounds Exam~le 4 0.15~ Citronellol 5350 cps 0.15% Dihydro Mercinol 4900 cps 6 0,15% Citronellal 3500 cps 7 0.15%~Citronella Nitrile 3000 cps 8 0.15% Fenchyl Acetate 2300 cps 9 0.15% i inalyl Acetate 2250 cps 0.15% Camphene 175p cps 11 0.15% Alpha-Pinene 1650 cps 12 0.15% Eucalyptol 2050 cps 13 0.15% Para Cymene 1700 cps 14 0O15~6 Terpinolene 1800 cps . . .

- l l -The base Formula I has a viscosity of 1900 cps. The se-lected compounds of Examples 4-14 were added separately to the base Formula I and the viscosity measured. The compounds of Examples 4-7 show profound impact on viscosity enhancement.
5 The compounds of Examples 8 and 9 show marginal improvement.
The compounds of Examples 10-14 show little or reduced viscosity impact.
Other VE compounds of the empirical formulas, e.g., men-thol, isoborneol, carvone and fenchone, were found to produce a 10 profound impact on the viscosity of Base Forml:lla 1.

Impact of LAS on Viscosity Base Formula l l Ingredient Wt. ~
- Soft water Balance Acrysol ICS-1 0.49 Surfactant:
- NaPS Variable ) see below LAS Variable ) Benzyl alcohol 1 . 5 NaOH (5096l 0.25 Na2C3 3 CaCO3 (same as above)30. 00 Perfume mix #1 2.15 ~272G58 Examples: 15 16 17 18 19 20 NaPS concentration 2 . 8% 2 . 89~ 2 . 896 2 . 8% 2 . 896 3 . 5%
LAS concentration 0 . 3 0 . 4 0 . 5 0 . 6 0 . 7 Viscosity ~cps) 1400 1900 2100 2500 3150 1500 Stability: Top OK OK OK OK Abrasive Layer at settles room temp.
1 0 only The above data show that combinations of NaPS and LAS
have synergistic benefits for viscosity enhancement, as well as phase stability.

Claims

WHAT IS CLAIMED IS:

1. An improved phase stable liquid scouring cleanser compo-sition comprising:
(a) from about 1% to about 10% of synthetic surfactant mixture of paraffin sulfonate (NaPS) and linear alkyl benzene sulfonate (LAS), said mixture of NaPS and LAS
having a ratio of from 20:1 to 2:1;
(b) from about 0.5% to about 5% of a mono- or sesquiterpene or mixtures thereof, the weight ratio of sur-factant:terpene lying between 20:1 to 3:2;
(c) from about 0.5 to about 3% of a polar solvent having a water solubility at 25°C in the range of from about 0.2%
to about 10%;
(d) from about 0.03% to about 0.5% of a compound selected from the group consisting of alcohols, aldehydes, acetates, ketones and nitriles of the formulas CnHmR
where n = 10 or 12; m = 14, 16, 17, 18 or 20 and R =
O, O2 or N;
(e) from about 1% to about 50% of a water-insoluble abra-sive; and (f) from about 0.40% to about 1% of a high molecular weight acrylic acid polymeric thickener having a molecular weight range of about 0.5 million to about 1.5 million;
and wherein the viscosity of said composition is from about 1800 to about 4000 cps and wherein the pH of said composition is from 8 to 12.

2. The composition of Claim 1 wherein the ratio of said mixture of NaPS and LAS is from 10:1 to 2:1 and is present in said composition at a level of from 2% to 896.

3. The composition of Claim 1 wherein the ratio of said mixture of NaPS and LAS is from 7:1 to 4:1 and is present at a level of about 2.5% to about 5%.

4. The composition in accordance with Claim 1 wherein the terpene is selected from d-limonene, dipentene, alpha-pinene and beta-pinene, and mixtures thereof, and is present at a concen-tration of 1% to 3% and wherein the weight ratio of surfactant mixture to terpene is 4:1 to 1.5:1.

5. The composition in accordance with Claim 1 wherein said (d) is present at a concentration of 0.05 to 0.5%.

6. The composition in accordance with Claim 1 wherein said polar solvent is benzyl alcohol present at a concentration of from 0.5 to 3%.

7. The composition in accordance with Claim 1 wherein the weight ratio of terpene to benzyl alcohol is in the range of from 5:1 to 1:5.

8. The composition in accordance with Claim 1 which in addition contains from 1% to 2% by weight of benzyl alcohol and wherein the ratio of terpene to benzyl alcohol is from about 2 :1 to about 1:2.

9. A composition in accordance with Claim 1 wherein (d) is selected from citronellol, geraniol, dihydro mercinol, linalool, nerol, rhodinal, alpha-terpineol, beta-citronellol, rhodinol, citronella nitrile, carvone, fenchone, menthol, isoborneol and mixtures thereof.

10. A composition in accordance with Claim 1 wherein (d) is selected from citronellol, dihydro mercinol, citronellal and citronella nitrile and mixtures thereof and is present at a level of 0.05% to 0.25% of said composition.

11. A composition in accordance with Claim 1 which comprises from 5% to 40% of an abrasive having a particle size range of 5-150 microns, said abrasive having a Mohs hardness of 7 and below.

12. A composition in accordance with Claim 11 wherein said abrasive is present at a level of 10% to 35%.

13. A composition in accordance with Claim 1 which comprises from 0.45% to 0.75% of said acrylic acid polymeric thickener and wherein said viscosity is from 2000 to 3500 and wherein said pH is 10 to 11.5.

14. A composition in accordance with Claim 1, 2 or 3 which comprises from 0.2% to 0.5% of a nonionic surfactant.

15. A composition according to Claim 4, 5 or 6 which comprises from 0.2% to 0.5% of a nonionic surfactant.

16. A composition according to Claim 8, 9 or 10 which comprises from 0.2% to 0.5% of a nonionic surfactant.

17. A composition according to Claim 11, 12 or 13 which comprises from 0.2% to 0.5% of a nonionic surfactant.