CA2325121A1

CA2325121A1 - Cleaning composition containing naturally-derived components

Info

Publication number: CA2325121A1
Application number: CA002325121A
Authority: CA
Inventors: Michael R. Rochon; Bernardus M. Tangelder
Original assignee: Cogent Environmental Solutions Ltd
Current assignee: Cogent Environmental Solutions Ltd
Priority date: 1999-11-04
Filing date: 2000-11-03
Publication date: 2001-05-04
Also published as: US6432395B1

Abstract

A less irritating cleaning composition is provided containing only naturally derived components. The composition preferably comprises lactic acid or other C2-C6 organic acid, alkyl polyglucoside, alkyl glucoester and collagen protein.

Description

ChEANING COMPOSITION CONTAINING NATURALLY-DERIVED COMPONENTS
1 aP,CKGROUND OF THE INVENTION

2 The present invention relates generally to cleaning 3 products, and more particularly, to cleaning products comprising 4 only naturally derived components that exhibit low skin irritancy and rapid environmental degradability. It is known that many 6 people experience a high degree of skin toxicity toward synthetic 7 cleaning products, with problematic results. Many individuals 8 suffer from chronic or acute skin irritation due to an unsanitary 9 home environment, because such individuals must refrain from using commonly available synthetic household cleaners for fear of lI residual skin irritation. In addition, synthetically derived 12 cleaning products, though somewhat environmentally degradable, 13 are known to persist under certain conditions and are suspected 14 of inducing negative biologic responses in the environment.
Some cleaning product formulations comprising naturally 16 derived components have been developed in response to the above.
17 However, existing natural cleaning products have met with minimal 18 acceptance in the marketplace due to recognized poor cleansing, 19 and similar levels of skin irritancy compared with synthetically derived cleaning products.
21 Consequently, there is a need in the art for a cleaning 22 product formulation comprising natural components~that exhibits 23 excellent cleansing, low skin toxicity, and high environmental 24 degradability or biodegradability. Such a cleaner must further provide a desired foam level and stability, hard water tolerance 26 and rinsing capability. The invented cleaning composition can be 27 used for glass and window cleaners, dishwashing and floor care 28 products and cleaners, food industry cleaners, laundry and carpet 29 cleaners, bathroom cleaners, dairy cleaners, general purpose and industrial cleaners, hard surface cleaners, metal cleaners, as 31 Well as transportation products.

2 An aqueous cleaning composition is provided comprising 3 0.004-28 weight percent naturally derived organic acid, 0.0035-36 4 weight percent naturally derived nonionic surfactant, and 0.0003-7 weight percent naturally derived anionic surfactant.

INVENTION
8 In the description that follows, when a preferred range, 9 such as 5 to 25 (or 5-25), is given, this means preferably at least 5, and separately and independently, preferably not more 11 than 25. When a range is given in terms of a weight percent 12 (wt.%) for a single component of a composite mixture, this means I3 that the single component is present by weight in the composite 14 mixture in the stated proportion relative to the sum total weight of all components of the composite mixture.
16 In .the preferred embodiments the cleaning formulation of the 17 present invention contains only naturally derived components and 18 is thus free from the presence of non-naturally-derived 19 components. As used herein, "naturally derived" means that a component is obtained or derived solely from naturally occurring, 21 or naturally regenerable resources, in contrast With synthetic 22 components which are artificially synthesized. For example, the 23 surfactants used in the present invention are wholly derived from 24 natural sugars and corn oil, and are termed "naturally derived"
because both sugars and corn oil are seasonably regenerable 26 resources. The preferred components (including branded or 27 trademarked components) described or suggested in this patent 28 application are all within the definition of "naturally derived".
2g The cleaner of the present invention comprises three principal components: an organic acid, an anionic surfactant, and 31 a nonionic surfactant. The organic acid is preferably C1-C2o, 32 more preferably C2-C12, more preferably C2-C8, more preferably 33 C2-C6, preferably non-fatty, preferably carboxylic, dicarboxylic 34 and tricarboxylic acid, preferably lactic acid. Less preferably, 1 other naturally derived organic acids, such as malic, citric, 2 malefic, succinic, gluconic, and polyaspartic acids, less 3 preferably other naturally derived organic acids, may be used.
4 Lactic acid is preferred because of its superior ability to solubili2e calcium carbonate and other hard water salts compared 6 With other naturally derived acids. The lactic acid also 7 solubilizes rust stains and serves as a preservative for the 8 surfactant components as explained below.
9 The anionic surfactant component may be a single naturally derived surfactant or a combination of multiple naturally derived 11 anionic surfactants. The preferred anionic surfactant is an 12 alkyl glucoester, though any suitable naturally derived anionic 13 surfactant may be used. The anionic surfactant provides enhanced 14 hard water tolerance, foam stability, and improved mildness to skin.
16 The nonionic surfactant component may be a single naturally 17 derived surfactant or a combination of multiple nonionic 18 surfactants. The preferred nonionic surfactant is an alkyl 19 polyglucoside, less preferably a sorbitan ester, though any suitable naturally derived nonionic surfactant may be used. The 21 nonionic surfactant provides effective surface tension reduction, 22 a low critical micelle concentration, and detergency.
23 Naturally derived surfactants, such as those used in the 24 present invention, are susceptible to "in-can" degradation and consequently are often used in other formulations with synthetic 26 preservatives such as glutaraldehyde and isothiazalone to prevent 27 such degradation. In addition to solubilizing hard mater salts, 28 the organic acid, preferably lactic acid, in the present 29 formulation preserves the naturally derived surfactants thus eliminating the need for additional synthetic preservatives.
31 This preservative character of lactic acid is helpful to the 32 present invention because it enables a cleaner formulation devoid 33 of synthetic components that might contribute to skin irritation.
34 The alkyl polyglucoside component with an average chain length of C12-C16 was found to exhibit excellent detergency and 36 streak-free rinsing on dilution; it is also useful in reducing 1 the critical micelle concentration. The alkyl polyglucoside with 2 an alkyl chain length of C8-clo was found to hydrotrope or couple 3 in the anionic alkyl glucoester and the C12-C16 alkyl 4 polyglucoside, which exhibited moderate solubilization or hawing.
Without the C8-C10 alkyl polyglucoside surfactant, the solution 6 exhibited poor stability at high temperatures.
7 Naturally derived alkyl glucoesters are extremely mild to 8 the skin compared to traditional anionic surfactants, and can 9 reduce irritancy of other components in the formulation. In addition, the anionic surfactant improves the hard water 11 tolerance of the alkyl polyglucosides.
12 Optionally, a naturally derived protein, preferably a 13 collagen protein, may be added to the cleaning formulation to 14 provide emolliency and enhance softness to the skin. Naturally derived collagen proteins reduce skin irritancy because they are 16 extremely absorptive to both skin and hair, and thus form a 17 protective barrier against irritation. The preferred invented 18 formulations are free or substantially free of non-naturally-19 derived or synthetic components. They have no or no significant quantities of or no intentionally added quantities of non-21 naturally-derived or synthetic components.
22 Cleaning formulations according to the present invention 23 have been developed for both kitchen and bathroom use, and glass 24 and surface use. The relative concentrations of the components have been optimized for each application to meet its unique 26 demands. The preferred relative concentrations of the individual 27 components are provided for each application in tables 1 and 2 28 below. A detailed description of the preferred species for each 29 component follows. AlI values in tables 1 and 2 are weight percents.

Table l: Glass and Multi-Surtace cleaner (Reaay-to-Use) Preferred Less PreferredEven Less Preferred 1. Organic Acid 0.22 0_026 - 18 0.004 28 0.044 - 8.8 0.0088 - 22 0.088 - 2.6 2. Nonionic Surfactant0.14 0.021 - 14 0.0035 - 21 0.035 - 7 0.007 - 17 0.07 - 2.1 4. Anionic Surtactant0.01 0.0024 - 1.2 0.0003 - 6 0_D03 - 0.3 0.0015 - Z.1 0.006 - 0.03 5. Protein 0.005 0,0005 - 0.3 0 - 0.5 0.001 - 0.1 0.00005- 0_25 0.0025 - 0.075 8. Water 99.83 Balance Balance Table 2: All Purpose Cleaner (Reaoy-to-USe/Dilutable) Preferred Less PreferredEven Less Preferred 1, Organic Acid 5.3 1.8 - 14 0.088 - 28 2.6 - 11 0.88 - 17_6 4.4 - 7 2. Nonionic Surfactant2.5 0.7 - 12 0.06 - 36 1.4 - 7 0.12 - 24 2 - 4.6 3. Anionic Surfactant0,75 0.03 - 1.5 0.003 - 7 0.3 - 1.1 0.015 - 3 0.6 - 0.9 4. Protein 0.05 0.0005 - 0.3 0 - 0.5 0.005 - 0.1 0.00005- 0.5 0.02 - 0.075 5. Water 91.4 Balance Balance I The following description pertains to the most preferable species 2 and form (source) for each of the constituent components listed 3 in tables 1 and 2 above. Unless otherwise indicated, the most 4 preferable form of a particular constituent is the same for both I the All Purpose, and Glass and Multi-Surface Cleaner 2 formulations.
3 The organic acid is most preferably lactic acid. The most 4 preferable source for lactic acid is Purac 88HS from Purac America, Inc. Purac 88HS is an approximately 88% active lactic 6 acid solution with the balance being Water. It should be noted 7 that, for example in the All Purpose formulation above, lactic 8 acid most preferably comprises 5.3 wt.% of the total composition, 9 meaning that 6.02 wt.% of Purac 88HS (which is only 88 wt.%
active lactic acid) is required to achieve the same 5.3 wt.%
I1 lactic acid in the All Purpose formulation. The relative 12 concentration of all remaining components from their respective 13 most preferred sources must be similarly accounted for when 14 computing the required total weight percent of a particular component source, or when substituting other, less preferred 16 sources for the components. For example, a 45 wt.% active malic 17 acid solution must comprise 11.78 wt.% of the All Purpose 18 gormulation to achieve the same 5.3 wt.% active organic acid.
19 The nonionic surfactant is most preferably an alkyl polyglucoside. With respect to the Glass and Multipurpose 21 Cleaner, the alkyl polyglucoside surfactant preferably has a 22 chain length in the range of C8-C10. with respect to the All 23 Purpose, the alkyl polyglucoside surfactant is preferably a 24 combination of two alkyl polyglucoside surfactants having chain lengths in the ranges of C8-C10 and C1z-C16 respectively.
26 Preferably, the C8-C10 and C12-C16 alkyl polyglucoside 27 surfactants are present in the All Purpose formulation in the 28 proportions listed in table 3 below. All values in table 3 are 29 weight percents.

Table 3: Preferred Concentrations of Cs-C10 and C12-C16 Alkyl Polyglucoside Nonionic Surfactants in All Purpose Cleaner Preferred Less Preferred Even Less Preferred ~ _ C8-C10 1.24 0.35 - 7 0.035 - 21 0.7- 3.5 0.07- 14 1 - 2.1 2. C 12-C 16 1.24 0.35 - 5 0.025 - 15 0.75 - 3.5 0.05 - 10 0.9 - 2.5 1 Glucopon 600 from Henkel is the preferred source for C12-C16 2 nonionic surfactant, and is 50 wt.% active C12-C16 alkyl 3 polyglucoside with the balance being water. Less preferably 4 Glucopon 625, less preferably other alkyl polyglucosides, less preferably other naturally derived nonionic surfactants, may be 6 used. Glucopon 220UP from Henkel is the preferred source for C8-7 C10 nonionic surfactant, and is 7o wt.~ active C8-C10 alkyl 8 polyglucoside with the balance being water. Less preferably, 9 Glucopon 220 or Glucopon 225, less preferably other alkyl polyglucosides, less preferably other naturally derived nonionic 11 surfactants may be used.
12 The anionic surfactant is preferably an alkyl glucoester.
13 Eucarol AGE-EC is the most preferred source for alkyl glucoester 14 anionic surfactant, and is 30 wt.% active disodium cocopolyglucose citrate alkyl glucoester with the balance being 16 water. It is available from Pilot Chemical Company. It has been 17 surprisingly effective in enhancing foam level and stability of 18 -the invented cleaners in the presence of tap water (hard water).
19 Less preferably Eucarol AGE-ET, less preferably other alkyl glucoesters such as sodium cocopolyglucose tartrate and disodium 21 cocopolyglucose sulfosuccinate, less preferably other naturally 22 derived anionic surfactants, may be used.
23 The protein is preferably a collagen protein- Lexein X-25o 24 from Inolex is the most preferred source for collagen protein, and is 50% active hydrolyzed collagen protein. The protein is an 26 optional component, though preferably comprises 0.005 wt.% and 27 0.05 wt.% of the Glass and Multi-Surface, and All Purpose 1 cleaners respectively, in order to reduce skin irritancy as 2 hereinbefore described. Less preferably Lexein X-300, less 3 preferably other naturally derived proteins, may be used.
4 Optionally, a naturally derived organic solvent may be added to the Glass and Multi-Surface Cleaner formulation. The most 6 preferable organic solvent is 100% ethanol. Other organic 7 solvents which may be used include Purasolv EL from Purac 8 America, Inc., ethyl lactate, amyl acetate, or other naturally 9 derived organic esters and solvents. The organic solvent may optionally comprise a combination of at least two naturally 11 derived organic solvents. An organic solvent may be added to the 12 Glass and Multi-Surface Cleaner formulation to aid solvation of a 13 particularly heavy greasy film or residue on a surface.
14 Preferably, an organic solvent would comprise 0-25, more preferably 0.0001-23, more preferably O.o1-20, more preferably I6 0.1-10, more preferably 1-5, more preferably about 3, wt_% of the 17 total formulation. The remaining active components would remain 18 at their above-stated weight percents with the weight percent of 19 water being reduced accordingly to accommodate the addition of the organic solvent.
21 As can be seen with respect the All Purpose Cleaner 22 formulation above, the preferred C12-C16 alkyl polyglucoside and 23 the preferred C8-C10 alkyl polyglucoside are present in 24 approximately equal amounts of their active components (about 1.24 wt.% each). Thus, the ratio of one to the other is 26 preferably 10:10. This ratio less preferably can vary from o:lo 27 to 1:10 to 3:10 to 5:10 to 7:10 to 9:10 to 10:9 to 10:7 to 10:5 28 to 10:3 to 10:1 to 10:0.
29 The All Purpose Cleaner is preferably provided in a bottle with a twist cap. It can be used full strength or diluted with 31 water to about or at least 3/4 , 1/2 , 1/4 , 1/8, 1/10, 1/15, 32 1/Z0, 1/30, 1/40, 1/80, 1/160 or 1/320 strength.
33 The Glass and Multi-Surface Cleaner preferably is provided 34 in a spray bottle. The invented composition preferably has a pH
of 2.5-12.5, more preferably 2.5-6 or 8-12, more preferably 3-5 1 or 9-11.5, more preferably 3.5-4.5 or 11-11.5, preferably 2 adjusted with caustic soda.
3 In addition to the components described above, one may add 4 naturally derived solvents, humectants (such as glycerin), thickeners, fragrances, etc., to achieve desired performance and 6 aesthetic characteristics.
7 The formulations are prepared or blended using customary and 8 known methods, the temperature preferably being ambient. The 9 product is used as per conventional methods, typically for floors, windows, hard surfaces, sinks, chrome, plumbing fixtures, 11 shower doors, showers, bathtubs, plastic surfaces, counter tops, 12 tables, furniture, cupboards, glass surfaces, and Formica 13 surfaces.
14 Tests have been conducted to determine the toxicity and degradability of cleaning formulations according to the present 16 invention. The invented cleaning formulations have exhibited 17 less than 0.05% volatile organic compound (VOC) content compared 18 with up to l0% Voc for conventional synthetic cleaners. VOCs 19 evaporate and pollute (contaminate) indoor air contributing to "sick building" syndrome which is known to aggravate certain 21 types of pulmonary conditions such as asthma. In addition, the 22 invented cleaners exhibited a dermal toxicity (LD 50) of greater 23 than 2000 mg/kg, which is considered to be non-irritating. Oral 24 toxicity for the invented cleaners Was also extremely low at 12,526 mg/kg.
26 The invented all naturally derived cleaners were found to 27 exhibit rapid environmental degradation and biodegradation 28 compared to conventional synthetic cleaners. The invented 29 cleaners degrade in the environment 58% in 5 days, B3% in 15 days, and 100% in 28 days, representing a significant improvement 31 in degree and rapidity of environmental degradation compared with 32 conventional synthetic cleaners. It is the current standard to 33 consider a product "readily biodegradable" if it degrades 60% in 34 2 s days .

1 The invented cleaners further exhibited anaerobic 2 degradation of 84.5% in 6 days. Anaerobic degradation of at 3 least 6o% in 56 days is considered acceptable by ASTM standard 4 test .methods for determining the Anaerobic Biodegradation of Organic Chemicals, Test Method 1196-92. A high rate of anaerobic 6 biodegradation indicates the potential for high biodegradability 7 in private septic systems, waste treatment plants, anaerobic 8 digesters, and in many naturally anaerobic environments such as 9 river and lake sediments.
Although the hereinabove described embodiments of the 11 invention constitute the preferred embodiments, it should be 12 understood that modifications can be made thereto without 13 departing from the scope of the invention as set forth in the 14 appended claims.

Claims

1. A cleaning composition comprising 0.004-28 weight percent naturally derived organic acid, 0.0035-36 weight percent naturally derived nonionic surfactant, and 0.0003-7 weight percent naturally derived anionic surfactant, said cleaning composition being an aqueous solution.

2. A cleaning composition according to claim 1, wherein said organic acid is a C2-C6 organic acid.

3. A cleaning composition according to any one of claims 1-2, wherein said organic acid is lactic acid.

4. A cleaning composition according to any one of claims 1-3, wherein said nonionic surfactant comprises an alkyl polyglucoside having a chain length in the range of C8-C10.

5. A cleaning composition according to any one of claims 1-4, wherein said nonionic surfactant comprises an alkyl polyglucoside having a chain length in the range of C12-C16.

6. A cleaning composition according to any one of claims 1-5, wherein said anionic surfactant is alkyl glucoester.

7. A cleaning composition according to any one of claims 1-6, wherein said anionic surfactant is disodium cocopolyglucose citrate alkyl glucoester.

8. A cleaning composition according to any one of claims 1-7, further comprising 0.00005-0.5 weight percent naturally derived protein.

9. A cleaning composition according to claim 8, wherein said protein is a collagen protein.

10. A cleaning composition according to any one of claims 1-9, further comprising 0.0001-25 weight percent naturally derived organic solvent.

11. A cleaning composition according to claim 10, wherein said organic solvent is selected from the group consisting of ethanol, ethyl lactate, amyl acetate and mixtures thereof.

12. A cleaning composition according to any one of claims 1-11, wherein said cleaning composition has a pH in the range of 2.5-6.

13. A cleaning composition according to any one of claims 1-12, wherein said nonionic surfactant is alkyl polyglucoside.

14. A cleaning composition according to any one of claims 1-13, wherein said nonionic surfactant is alkyl polyglucoside and said anionic surfactant is alkyl glucoester.

15. A cleaning composition according to any one of claims 1-6 and 8-14, wherein said anionic surfactant is selected from the group consisting of disodium cocopolyglucose citrate, disodium cocopolyglucose sulfosuccinate, sodium cocopolyglucose tartrate and mixtures thereof.

16. A cleaning composition according to any one of claims 1-15, wherein said composition comprises 0.88-17.6 weight percent said organic acid, 0.12-24 weight percent said nonionic surfactant, and 0.015-3 weight percent said anionic surfactant.

17. A cleaning composition according to any one of claims 1-16, wherein said composition has a pH of 3.5-4.5.