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© (^) Publication number: 0 2 0 9^ 2 2 8 A 1
02) E U R O P E A N P A T E N T A P P L I C A T I O N
(ay (^) Application number: 86303980.6 (^) © Int. CI.4: C1 1 D 3/ , C1 1 D 3 / 3 9 5 © (^) Date of filing: 27.05.
© (^) Priority: 17.06.85 US 745617 (^) © (^) Applicant: The Clorox Company 1221 Broadway @ Date of publication of application: (^) Oakland California (^) 94612(US) 21.01.87 Bulletin 87/ © Inventor: Mitchell, James D. © (^) Designated Contracting States: (^) 320 East Angela Street BE CH DE FR GB IT LI LU NL SE (^) Pleasanton (^) California (^) 94566(US) Inventor: Farr, James P. 4885 Harrison Street Pleasanton California (^) 94566(US) Inventor: Carty, Daniel T. 50 Tyrrel Court Danville California (^) 94526(US)
© (^) Representative: Ford, Michael Frederick et al MEWBURN ELLIS & CO. 2/3 Cursitor Street London EC4A 1BQ(GB)
£) Stabilized^ liquid hydrogen (^) peroxide bleach (^) compositions.
curopaiscnes fatentamt European Patent^ Office Office europeen des brevets
(57) Aqueous (^) peroxide bleaching (^) compositions that include (^) surfactant, fluorescent (^) whiteners and (^) dyes are (^) effectively stabilized (^) by the addition of a heavy metai (^) chelating (^) agent and (^) a free radical (^) scavenging agent. Both agents must be present to achieve maxi- mum stability. (^) Particularly preferred (^) chelating agents are the^ amino^ polyphosphonates. (^) Particularly (^) pre- ferred free radical scavenging (^) agents are the hydrox- ybenzenes and^ especially substituted (^) phenols. Not only is the^ peroxide (^) oxidizing agent stabilized, but surfactant, fluorescent whitener, and dye as well.
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STABILIZED LIQUID HYDROGEN PEROXIDE BLEACH COMPOSITIONS
This invention relates to household^ fabric bleaching compositions, but^ more particularly to liquid peroxide, (^) e.g., hydrogen peroxide based bleaching compositions including additional^ ad- juncts such^ as surface^ active^ agents, fluorescent whiteners, and dyes. The (^) bleaching compositions have the (^) peroxide and certain (^) adjuncts therein sta- bilized (^) by the addition of agents to chelate (^) heavy metal cations and scavenge free radicals. Liquid bleaches^ have been^ used^ in households for at least 50-75 (^) years as aids in the (^) bleaching and cleaning of fabrics. (^) Hypochlorite bleaches have been used (^) most extensively for this purpose since
they are highly effective,^ inexpensive and simple to produce. In an attempt to broaden and extend the utility of bleaches for household (^) use, other bleach (^) sys- tems have^ been^ introduced^ in recent years. Promi- nent (^) among these are dry powdered or granular compositions, most usually based (^) upon peroxy- compositions; or upon perboro-compositions.^ Such materials must be (^) placed into (^) aqueous solution to release the bleaching action. Liquid bleaching compositions utilizing (^) peroxy compounds have generally been utilized less in the household market than the solid forms referred to above. (^) Although hydrogen peroxide compositions effectively bleach^ a broad^ range of fabric materials; are less^ harsh^ than^ hypochlorite bleaches; and^ do not release objectional (^) gases or odors; they have not found as much (^) use in the household market as hypochlorite bleaches.^ This^ lack^ of^ use in^ the household market has been (^) partially attributable to the (^) instability of peroxide solutions. This (^) instability is mediated (^) principally by metal ion contamination even in extremely low concentrations.^ Considerable effort has been (^) expended in the search for stabiliz- ing agents for hydrogen peroxide compositions. Perhaps one reason^ why^ stabilized^ hydrogen peroxide compositions have not been^ successful^ is the fact that it is (^) very desirable to add other (^) or- ganic components to commercial^ bleaching com- positions, especially where^ the^ compositions^ are intended to be used (^) as "pre-spotters". Such (^) "pre- spotter" compositions most advantageously include surfactants for their (^) detergent effect; fluorescent whiteners (also known as optical (^) brighteners) to increase fabric reflectance and the user's (^) percep- tion of increased (^) whiteness; and (^) dyes for produc- ing a pleasing color to the^ bleach^ solutions.^ All of the above (^) components, in addition to the bleach compounds themselves^ have^ been^ found^ to^ be necessary in^ a^ liquid^ peroxygen bleaching^ com- position to^ achieve^ full^ acceptance in the^ house- hold market.
Unfortunately liquid (^) bleaching compositions based (^) upon peroxide not only deteriorate from the presence of contaminants,^ e.g., trace^ metal^ cations (0.5ppm or greater); but the surfactant, fluorescent 5 whiteners,^ and^ dyes are attacked^ by the^ peroxide itself, as it^ is^ a powerful oxidizing (^) agent. Thus peroxide based^ bleaching compositions including surfactants, fluorescent whiteners, and (^) dyes dete- riorate (^) quite rapidly. The surfactants (^) are oxidized 70 and^ lose^ their^ detergency; the fluorescent whiten- ers are oxidized^ and lose their effect; and the dyes are oxidized^ and lose their color, or are changed to undesirable colors. The (^) present invention is (^) directed to methods 75 for stabilizing liquid hydrogen peroxide based (^) com- positions, and^ more especially to stabilizing liquid peroxide bleaching compositions that^ also^ include surfactants, fluorescent^ whiteners, and^ dyes. The invention is also directed to compositions produced 20 by such methods. More (^) particularly the (^) present invention relates to liquid hydrogen peroxide bleaching compositions (including the^ aforementioned^ additional^ compo- nents) that are stabilized^ by the addition^ of a metal 25 chelating (^) agent as well as a free radical scavenging agent thereto.^ The^ presence of both^ the^ chelating agent and free radical^ scavenging agent are neces- sary to achieve the desired^ stability. The metal (^) chelating or sequestering agent may 30 be selected from among the known metal (^) chelating agents. A preferred (^) group of such^ chelating agents are the^ amino^ polyphosphonates which^ are known to sequester metal ions such as Fe+ +* and Cu ++. The free (^) radical (^) scavenging agent (^) may be se- 35 lected^ from^ organic antioxidants,^ especially the substituted mono-and (^) di-hydroxybenzenes and their analogs. Stabilization (^) of hydrogen (^) peroxide composi- tions including the associated fluorescent whiteners 40 (also known^ as optical brighteners), surfactant, and dye components relies^ upon the (^) presence of both the (^) metal (^) chelating agent and the free radical scavenging agent. The stabilizing agents need only be (^) present in very small (^) amounts, (^) e.g., tenths (^) to 45 hundredths^ of^ a percent by weight of the liquid composition, in order to effectively (^) prevent deterio- ration and retention of the desired (^) strengths of the various components over extended (^) periods of time. As utilized (^) herein, "stabilization" (^) refers to the so retention of physical and chemical (^) properties at, or somewhat below their initial levels (^) by each of the liquid bleach composition components for extended periods of time;^ and^ a significant reduction^ in the
. rate^ of deterioration^ of such^ components^ in com- parison to unstabilized^ formulations. Thus, in the
H 2 ° 2 +^ -
H H
1 I
O - C - C - H
I I
H H
H H
i i h o ; OH (^) + - O - C - C - H 1 I H H
( h y d r o g e n a b s t r a c t i o n )
OH +
H
. I
- O - C - C - H
I I
H H
H 2 0
( f r e e r a d i c a l f o r m a t i o n )
Alternately, the^ hydrogen peroxide itself^ may form free radicals (^) by homolytic cleavage of either an O-H bond or the 0-0^ bond. That is:
HO (^). O H (^) ■» *H^ OOH (^) , o r
H O I O H -> 2 O H
In any event, there (^) are a number of mecha- nisms (^) by which free radicals (^) can occur in the peroxide-organic composition. By a little^ under- stood mechanism it appears that the (^) presence of heavy metal cations also promote the generation of free radicals. Such free radical reactions (^) are self- propagating and become a chain reaction until a termination product is produced. By such time, in the absence of any stabilization (^) means, both the peroxide and the organic components are, in large measure, destroyed. Once formed, any such free radicals are free to combine with other organic species in the solution,
e.g., the^ optical^ brighteners^ and^ dye.^ Such^ free radicals would be (^) especially reactive with (^) com- pounds having conjugated double bonds, e.g., dyes and brighteners. In the (^) stabilizing system of the invention, the chelating agent (^) appears to act^ to (^) sequester the heavy metal^ cations, (^) especially polyvalent metals such (^) as copper and iron which are always present in small amounts (^) among the mineral (^) components in water. Thus the (^) heavy metal cations' (^) ability to
catalyse peroxide homolysis is^ interfered^ with. Similarly the^ heavy metals'^ ability to mediate^ free radical generation is eliminated or greatly reduced.
The free radical (^) scavenging (^) agent appears to work by tying (^) up any free radicals (^) initially formed in the solution. Thus the ability of the free radicals to degrade the (^) organic components is removed at the same time the (^) self-propagating free radical cascade reactions (^) are stopped short. (^) By such (^) a mechanism, destruction of the desired (^) surfactant, optical whitener, dye, and^ perfume (^) components is arrested (^) or greatly reduced. It should be understood that the (^) foregoing is presented as a possible explanation for the surpris- ing stability imparted to peroxide (^) bleaching com- positions; but the inventors do hot thereby intend to be (^) bound by such (^) explanation. Other (^) plausible reactions (^) may be responsible for the (^) improvement in stability. Yet the individual (^) functions of the (^) chelating agent and the free radical scavenger do not explain why such^ surprising improved stability is achieved by the^ present invention. When the two component stabilizing (^) system is used in liquid peroxide bleach compositions, decomposition of the^ organic com- ponents therein^ is dramatically decreased, (^) even over the (^) stabilizing abilities of the (^) chelating agent and the free radical (^) scavenger considered individ- ually. Therefore^ the combination of the (^) chelating
agent ana^ tne^ Tree^ raaicai^ scavenger (^) appears to possess synergistic action^ in improving stability of liquid peroxide (^) compositions containing (^) organic components. Referring to the stabilized (^) peroxide composi- tions (^) of the invention, (^) a peroxide source is present
as the^ principal active (^) ingredient and functions (^) as the (^) bleaching agent. The (^) peroxide is (^) normally
present as hydrogen peroxide and is present in the range of about^ 0.05-50^ weight %, most usually at about 0.1-35 (^) wt.%, and (^) most preferred at 0.5- wt.%. The (^) hydrogen peroxide is a staple article of commerce available from (^) a number of commercial sources. In making (^) up the (^) bleaching (^) compositions, ordinarily the^ peroxide is^ purchased as a con- centrated (^) aqueous solution, (^) e.g., 70%, and diluted with (^) deionized water to the desired (^) strength. The FMC (^) Corp. of (^) Philadelphia, (^) Pennsylvania is (^) one source of hydrogen (^) peroxide. Surfactants (^) are desirable for use in the bleach- ing compositions. Not (^) only do (^) they perform the normal soil (^) removing function; (^) but, in the (^) present formulations, (^) they also assist in (^) emulsifying the free radical (^) scavenger into the (^) aqueous bleach formulation. As (^) will be noted (^) hereinafter, the free radical (^) scavenger component is (^) somewhat (^) hydro- phobic. The surfactant therefore assist (^) mixing of free radical (^) scavenger into the (^) bleach (^) composi- tions. As will be also noted hereinafter, the surfactant component can (^) provide a thickening effect; (^) espe- cially when used in higher concentrations, such (^) as when exceeding about 5 wt.%. The most (^) preferred surfactants (^) are nonionics. Suitable (^) nonionics include (^) polyethoxylated alco- hols, (^) ethoxylated alkyl phenols, polyoxyethylene (^) or polyoxypropylene block^ co-polymers, (^) anhydrosor- bitol esters, aikoxylated anhydrosorbitol (^) esters, and the like. Other (^) potentially suitable surfactants (^) are disclosed in (^) the Kirk-Othmer Encyclopedia (^) of Chemical (^) Technology. 3rd (^) Edition, Volume 22, pp. 360-377 (1983), the disclosure of (^) which is incor- Dorated herein (^) by reference. Such (^) nonionic surfac- tants (^) may be obtained (^) from (^) any number of com- Tiercial (^) sources. One (^) such (^) source for (^) polyethox- ylated alcohols^ is the Shell Chemical Co. of Hous- :on, Texas^ and^ are known^ under the tradename "Neodol". One suitable (^) surfactant is "Neodol (^) 25- f"\ This (^) Neodol is an ethoxylated alcohol, wherein tie (^) alcohol has from 12-15 (^) carbons to which 7 3thoxy groups are attached. (^) Anhydrosorbitol (^) esters Including sorbitan^ esters) are available from (^) Atlas Dhemical (^) Industries under (^) the tradenames Tween" and "Arlacel". The surfactant (^) may be present in the composi- ions in about (^) 3-4 weight %, although this (^) level is lot critical. Lower, (^) or higher surfactant concentra- ions (^) are acceptable within the (^) ranges noted. (^) The
preferred (^) range for surfactant is (^) 0-50 (^) wt.%; the more preferred (^) range is 0-20 (^) wt.%; and the (^) most preferred (^) range is 0-10 wt.%. At higher levels, and, as noted above, the surfactants (^) may beneficially 5 have a thickening effect on the liquid compositions. Such (^) thickening would aid in (^) the dispersion of particulate components such (^) as dyes and whiten- ers. Also, as noted above, the surfactants (^) may also assist in (^) emulsifying the (^) liquid compositions and to aid^ in the^ suspension of some of the free (^) radical scavengers since they tend to be somewhat insolu- ble in aqueous medium. (^) Mixtures of the surfactants are also suitable. Fluorescent whiteners (^) (also referred to as (^) op- 75 tical brighteners, or FWA's) are also included in the bleaching formulations. Such whiteners (^) are also common commercial (^) products. Such (^) products are fluorescent (^) materials, (^) very often substituted stii- benes and (^) biphenyls, (^) having the (^) ability to flu- (^20) oresce, by (^) absorbing ultraviolet (^) wavelengths of light, and then emitting visible light, generally in the blue wavelength (^) ranges. The whiteners settle out or deposit onto the fabrics (^) during the (^) bleaching or washing (^) process to thereby (^) impart the desired 25 whiteness.^ The whiteners (^) may be (^) present in the bleaching (^) compositions in the order of several hun- dredths to about 5 wt.%, more preferably 0-1 wt.%, and most (^) preferably 0-0.6 (^) wt.%. One (^) source of such whiteners is the (^) Ciba Geigy (^) Corp. of Greens- jo boro, North^ Carolina, under the tradename "Tinopal". Other^ useful whiteners (^) are disclosed in U.S. (^) Patent 3,393,153 to Zimmerer (^) et. al., at col- umns 3-5, which disclosure is incorporated herein by reference. ?5 Several^ different whiteners (^) may be (^) combined in the (^) compositons. Such selection (^) is governed by the fact that certain whiteners have (^) affinity for cel- lulose fibers, (^) e.g., cotton; while others have (^) affinity for synthetic fibers, e.g., nylon. Since the bleaching to compositions of the invention (^) are intended for all types of fabrics,^ both^ natural^ and (^) synthetic, it is advantageous to^ include^ whiteners of both (^) types. One stilbene based (^) product, (^) "Tinopal RBS" has affinity for synthetic fibers. A distyrylbiphenyl (^) prod- is uct^ "Tinopal CBS-X" has (^) affinity for (^) cellulose fi- bers. Small (^) amounts of dye are also included in the preferred (^) bleaching compositions. While the dye is only (^) a very small (^) percentage (perhaps (^) 0.0005) of ;o the^ compositions, it (^) plays an (^) important part in consumer's (^) acceptance of the (^) product. It is (^) pre- ferred (^) that such (^) dye be present in the range of 0- wt.%, more preferably 0-0.1 wt.%, and most prefer- ably 0-0.001^ wt.%. Dyes such (^) as the (^) anth- 5 raquinones are (^) particularly suitable. Such (^) anth- raquinone dyes (^) are available from the (^) Sandoz Co. of Charlotte, North Carolina. One (^) suitable (^) dye is "Nylosan 2AL" from the aforementioned (^) company.
nnaiiy it^ is^ aesiraoie^ tnat^ the^ free^ radical scavenging hydroxybenzenes be partially hindered, i.e., have^ a substituent (^) alkyl or similar (^) group at- tached to (^) some of the (^) reactive sites (^) on the (^) ring structure. If too (^) many reactive sites (^) are left (^) un- blocked, it may be possible to react with more than one available^ free^ radical and (^) polymerize, thus causing phase (^) separation. Any such phase (^) separa- tion is undesirable and would (^) remove free radical scavenging (^) agent from the bleach (^) solution.
The aforementioned BHT and MTBHQ (^) satisfy all the above criteria and are therefore (^) preferred (^) as the free radical (^) scavenging (^) agent. BHT is commer- cially available from the (^) Uniroyal Chemical Co. 5 while^ MTBHQ^ is^ commercially available (^) from the Eastman (^) Chemical Co. of Kingsport, Tennessee. Only (^) very small^ amounts of the free radical scavenger are^ necessary in the^ bleach (^) composi- tions. Generally, (^) one to (^) several hundredths of (^) a w percent provides effective free radical (^) scavenging. The (^) preferred (^) range is 0.005-0.04 wt.%. The more preferred (^) range is 0.007-0.03 (^) wt.%; however the most preferred (^) range is 0.01-0.02 wt.%. As an example, a typical stabilized bleach (^) for- 15 mutation is set forth below:
e & h U L A & h U (^) S T A B I L I Z E D B L E A C H I N G F O R M U L A T I O N S
C o m p o n e n t
N o n i o n i c s u r f a c t a n t ( N e o d o l )
F l u o r e s c e n t w h i t e n e r - (^) d i s t y r y l b i p h e n y l
Blue (^) dye - (^) a n t h r o q u i n o n e
F r a g r a n c e
H Z ° 2
P h o s p h o n a t e (^) c h e l a t i n g (^) a g e n t
F r e e r a d i c a l (^) s c a v e n g e r
P h o s p h o r i c a c i d
~ (^) d e i o n i z e d
m numDer or tests were performed to ascertain the effectiveness of the (^) stabilizing system of the aresent invention. (^) Several (^) samples of (^) hydrogen seroxide bleach (^) compositions were (^) prepared hav- ng variations^ in^ components and (^) percentages thereof.
Wt. %
s u f f i c i e n t t o a d j u s t (^) pH to 2. 3
' (^) r e m a i n d e r 1
One formulation (^) had the composition:
■FORMULATION A
H2Oz 3.5^ w t. %
W h i t e n e r (^) ( d i s t y r y l b i p h e n y l ) (^) 0. 1
Acid b l u e (^) dye (^) 0. 0 0 0 5
_ _ S u r f a c t a n t (^) ( C ^ - 1 5 e t h o x y l a t e d a l c o h o l )^ 3. 5
Free r a d i c a l (^) s c a v e n g e r ( M T B H Q ) (^) 0. 0 3
C h e l a t i n g (^) a g e n t ( p h o s p h o n a t e ) (^) 0. 1 0
B u f f e r (^) ( p h o s p h o r i c acid) (^) 0. 0 2 5
**20 B a l a n c e Another formulation had the composition: 20
' F O R M U L A T I O N B
H202 3.5^ w t. %
W h i t e n e r - (^) ( n a p h t h o t r i a z o l y l s t i l b e n e ) 0. 0 2 ( d i s t y r y l b i p h e n y l ) 0. 1 5
F r a g r a n c e oil^ 0. 0 1
Acid b l u e (^) dye 0. 0 0 0 5
S u r f a c t a n t (^) ( C ^ - I S e * ^ o x y ^ a t e c i a l c o h o l ) (^) 3. 5
Free r a d i c a l (^) s c a v e n g e r ( B H T ) 0. 0 1
C h e l a t i n g a g e n t ( p h o s p h o n a t e )^ 0. 1 2
E u f f e r (^) ( p h o s p h o r i c acid) (^) 0. 1
H20 B a l a n c e
Another formulation had the composition: (^) ^
1/ 0 209 228^18
F O R M U L A T I O N B
T a b l e (^) 2i 4 Week (^) S t o r a g e (^) S t a b i l i t y T e s t
120° F (^) ioo° F
B l e a c n F o r m u l a t i o n
B l e a c h F o r m u l a t i o n
o i e a c n +^ u e q u e s t B l e a c h (^) + (^) D e q u e s t F o r m u l a t i o n (^) + BHT (^) F o r m u l a t i o n (^) + B H T , ( u n s t a b i l i z e d ) (^) + l p p m Fe (^) + l p p m Cu C^ ( U n s t a b i l i z e d ) (^) + l p p m Fe 3 + l p p m (^) Cx (•s (^) r e m a i n i n g ) (% (^) r e m a i n i n g ) (% (^) r e m a i n i n g ) - (% r e m a i n i n g )
- (^) D e q u e s t _ + _ B ^ 3. , _
H 2 U 2
W h i t e n e r
D y e
J
in anotner (^) sway, similar aging tests were con- Jucted for (^) a period of (^) eight weeks (^) at (^) storage emperatures of 70 °F, 100°F, and 120°F. Table 3 )elow (^) presents the results of these (^) longer aging ests.
FORMULATION B
Table 3: (^8) Week Stability T e s t 1
Storage Temp.^ 70°F^ 100°F^ 120°F *2 3 *2^3 * Component S^ Uns.^ S^ Uns.^ S^ U n s ,
H2Oz 100 92.3^97 77 96
Whitener 100 57 94 13 56 10
Dye 96.8^51 83 0 55
The n u m b e r s shown^ r e p r e s e n t the % of the (^) component remaining a t the end^ of^ the^ test (^) p e r i o d.
"S" i n d i c a t e s (^) stabilized (^) composition
"Uns" indicates u n s t a b i l i z e d (^) composition
in (^) some further tests, stabilized (^) samples of Formulation B and C above (^) were aged at various temperatures in order to follow the deterioration (^) of the various components with time. Catalyzing metal cations (^) (5 ppm) (^) were added to the (^) stabilized for- mulations. (^) The results (^) are set forth (^) in Table 4 and 5 below:
to
o
F O R M U L A T I O N D
H 2 ° 2
Acid b l u e (^) d y e
F r e e r a d i c a l (^) s c a v e n g e r ( M T B H Q )
C h e l a t i n g (^) a g e n t ( p h o s p h o n a t e )
B u f f e r (^) ( p h o s p h o r i c a c i d )
H z O Formulation D above, (^) along with (^) an identical formulation that omitted (^) the free radical (^) scavenger and the chelating agent were boiled for three hours and the samples were analysed for deterioration of the dye as a measure of formulation stability. Table 6 below sets forth the results:
3.5 w t. %
B a l a n c e
F O R M U L A T I O N D
T a b l e 6; 3 H o u r s (^) at 100° C
C o m p o n e n t
D y e
U n s t a b i l i z e d
S t a b i l i z e d
I n d i c a t e s (^) p e r c e n t a g e of (^) o r i g i n a l (^) c o m p o n e n t r e m a i n i n g at end of (^) t e s t.
i ne results indicate that the formulation (^) is sta- bilized even in the absence of surfactant.
Claims
- Stabilized (^) peroxide compositions comprising or (^) consisting essentially of (^) a (^) peroxygen compo- nent, a metal^ chelating (^) agent, a free radical scavenging agent, and water.
- (^) Stabilized (^) liquid peroxide bleaching com- positions (^) comprising (^) aqueous compositions of (^) a
peroxygen component,^ an^ organic^ component se- lected from nonionic (^) surfactants, fluorescent whit-
sners, a dye,^ and^ mixtures^ thereof,^ and^ a stabiliz- ng system comprising a chelating agent and a free radical scavenging (^) agent.
- The (^) compositions of claim (^1) or claim (^2) Further including a fragrance.
OU
SO
- The (^) compositions of any one of the preced- ing claims^ wherein^ the^ peroxygen component is present in about 0.05-50 percent by weight.
- The compositions of any one of the preced- ing claims further including a buffer to maintain (^) pH of about 1-8.
- A method for stabilising peroxide based (^) oxi- dizing or (^) bleaching compositions (^) comprising ad- mixing into^ said^ compositions a (^) chelating agent and a free radical scavenging agent.
- A method for stabilizing organic components of liquid peroxide (^) bleaching formulations (^) into which said (^) organic components have been (^) mixed, (^) com- prising further^ admixing into said (^) peroxide bleach- ing formulations^ a free radical (^) scavenging agent and a metal chelating (^) agent.
- A method for (^) stabilizing (^) aqueous bleach formulations (^) including a (^) peroxygen component, surfactant, fluorescent^ whiteners, and dye compris- ing admixing into said formulation (^) a chelating agent and a free radical scavenging agent.
- The methods or compositions of any one of the preceding claims wherein said (^) peroxygen com- ponent is hydrogen peroxide.
- The methods or compositions of any one of the (^) preceding claims wherein said (^) nonionic surfac- tant is selected from the (^) group consisting essen- tially of polyethoxy-lated alcohol, (^) ethoxylated alkyl phenols, polyoxypyropylene or polyoxyethylene block copolymers, and mixtures thereof. (^11). The methods or compositions of any one of the (^) preceding claims wherein said (^) chelating (^) agent is (^) capable of (^) forming chelates with (^) polyvalent heavy metal cations.
- The methods (^) or compositions of claim 11 wherein said (^) chelating (^) agent is (^) an amino (^) poly- phosphonate.
- The methods (^) or compositions of any one of 5 the^ preceding claims wherein said free radical scavenging (^) agent is a substituted (^) hydroxybenzene.
- The methods (^) or compositions of claim (^13) wherein the substituted (^) hydroxybenzene is a sub- stitued hydroquinone or is butyl hydroxytoluene. w 15. The methods (^) or compositions of claim 14 wherein the substituted (^) hydroquinone is mono-tert- butyl hydroquinone.
- The methods (^) or compositions of any one of the (^) preceding claims wherein the fluorescent whit- T 5 eners are selected^ from^ fluorescent^ derivatives of stiibene and (^) distyrylbiphenyis, and mixtures there- of.
