AU693793B2 - Stable aqueous emulsions of nonionic surfactants - Google Patents

Description

i- i 68 lgl WO 94/29415 PCT/US94/06117 1GSTABLE AQUEOUS EMULSIONS OF NONIONIC SURFACTANTS STABLE AQUEOUS EMULSIONS OF NONIONIC SURFACTANTS Technical field The present invention relates to cleaning compositions.

More particularly, the cleaning compositions according to the present invention are stable aqueous emulsions of nonionic surfactants particularly suitable for the pretreatment of laundry or the cleaning of hard surfaces.

BackQround A great variety of cleaning compositions have been described in the art. For instance, in co-pending European Patent Application EP 92870188.7, a particular type of cleaning compositions is described which are aqueous emulsions of a nonionic surfactant system. Such emulsions find a preferred application in the formulation of bleaching compositions comprising hydrogen peroxide or water soluble source thereof and a liquid hydrophobic bleach activator, or any other hydrophobic ingredient which needs to be separated from hydrogen peroxide. Alternatively, such emulsions can be used to formulate products which do not contain hydrogen peroxide.

In the latter case, such emulsions can be useful because they WO 94/29415 PTU9/61 2 K allow to keep a given hydrophobic ingredient separate from the aqueous phase, with which said hydrophobic ingredient could react, by hydrolysis. Another advantage of such emulsions is that they provide a means to formulate ingredients with very low water solubility, without the need.

K for using alcoholic or solvent mixtures, which are usually undesirable for aesthetic (odour) and toxicity reasons.

A problem with such emulsions, especially with emulsions containing relatively high concentrations of surfactants, e.g, about 8 is that important viscosity tends to build up, which makes said emulsions difficult to dispense, and thus unacceptable from a consumer viewpoint.

It would therefore be desirable to formulate aqueous emulsions of nonionic surfactants wherein the viscosity can be conveniently controlled.

Various viscosity agents such as sodium cumene suiphonate and polyacrylates; have been tried in this context, which resulted in a decreased viscosity but also reduced phase stability.

It would thus also be desirable to provide 00 aqueous emulsions of nonionic surfactants wherein the H viscosity can be conveniently contr.olled while maintaining H adequate physical stability.

In order to manufacture such aqueous emulsions of nonionic surfactants, it is necessary to vigorously mix the ingredients together. During this vigorous mixing, lots of air bubbles are generated which are detrimental both to the composition's aesthetics and stability. Indeed, surf actants tend to concentrate at the air/liquid interfaces generated by said air bubbles. Thus the more air bubbles a composition contains, the less surf actants will be available for the stabilisation of the droplets of the dispersed phase. This problem of air bubbles is aggravated in that aqueo's WO 94/29415 PCTJUS94/06117 3 emulsions of nonionic surfactants are pseudoplastic fluids, i.e. they have a higher viscosity at low shear rates.

Consequently, the air bubbles generated upon mixing, i.e. at low viscosity become entrapped in the compositions when mixing stops and viscosity consequently raises. For the same reasons, air bubbles tend to become entrapped in the compositions also when the product is pulled from the bottle into another container, i.e. a dosing device, or when the bottle is shaken.

It would thus also be desirable to provide aqueous emulsions of nonionic surfactants which are substantially free of air bubbles and thus acceptable for aesthetics and stability.

It has now been found that the present invention efficiently provides for the formulating of aqueous emulsions of nonionic surfactants which comprise silicons compounds. In other words, it has now been found that silicone compounds reduce the viscbsity of aqueous emulsions comprising a nonionic surfactant system whatever the viscosity was before their addition and allow to substantially eliminate the air bubbles. Additionally, it has unexpectedly been found that emulsions comprising silicone compounds are physically more stable than emulsions without said silicone compounds.

The present invention allows for greater flexibility in formulating and provides stable aqueous emulsions suitable to be used in the most efficient manner by the consumer.

SThe viscosity-reducing effect and the air bubbles removal properties of the silicone compounds are unexpected and beneficial as said silicone compounds are only known in the context of laundry compositions as sud-suppressing agents, see for instance US 4 076 648, US 4 021 365, US 4 749 740, US 4 983 316, EP 150 872, EP 217 501 and EP 499 364.

4 As an additional advantage it has been found that the present invention finds a preferred application in formulating aqueous activated bleaching emulsions and bleaching emulsions which comprise any hydrophobic liquid ingredient which needs to be kept separate from the hydrogen peroxide. Indeed, the addition of silicone compounds according to the present invention to the nonionic surfactant i system used to emulsify hydrophobic liquid ingredients as for instance bleach Ii activators improves the storage stability of hydrogen peroxide.

Summary of the Invention a The present invention is a stable aqueous emulsion having a pH of from i 0 0.5 to 6, comprising a hydrophilic nonionic surfactant and a hydrophobic nonionic surfactant, said stable aqueous emulsion further comprises an effective amount 15 of silicone compounds.

l The present invention further provides a detergent composition comprising i an emulsion as herein described.

i Throughout the description and claims of this specification, the word "comprise" and variations of the word, such as "comprising" and "comprises", is not intended to exclude other additives or components or integers or steps.

Detailed Description of the Invention The compositions according to the present invention are stable aqueous emulsions of nonionic surfactants. By stable emulsion it is meant an emulsion which does not substantially separate into distinct layers, upon standing for at least 2 weeks at The compositions according to the present invention are aqueous.

Accordingly, the compositions according to the present invention comprise from 10% to 95% by weight of the total composition of water, preferably from 30% to most preferably from 60% to 80%. Deionized water is preferably used.

C.AWINWORDVAELISSAIHWODELETEXSPECI%981 EQ.DOC ii WO 94/29415 PCT/US94/06117 II The compositions according to the present invention are emulsions of nonionic surfactants. Said emulsions of nonionic surfactants comprise at least two nonionic I surfactants. Said two nonionic surfactants in order to form j emulsions which are stable must have different HLB values i (hydrophilic lipophilic balance), and preferably the difference in value of the HLBs of said two surfactants is at least 1, preferably at least 3. By appropriately combining at least two of said nonionic surfactants with different HLBs in water, emulsions according to the present invention will i be formed.

One of said nonionic surfactants used herein is a nonionic surfactant with an HLB above 11 (herein referred to as hydrophilic nonionic surfactant), whereas the other one is a Snonionic surfactant with an HLB below 10 (herein referred to

I

as hydrophobic nonionic surfactant).

i Suitable nonionic surfactants for use herein include Salkoxylated fatty alcohols. Indeed, a great variety of such alkoxylated fatty alcohols are commercially available which have very different HLB values. The HLB values of such alkoxylated nonionic surfactants depend essentially on the i chain length of the fatty alcohol, the nature of the alkoxylation and the degree of alkoxylation. Hydrophilic nonionic surfactants tend to have a high degree of alkoxylation and a short chain fatty alcohol, while hydrophobic surfactants tend to have a low degree of alkoxylation and a long chain fatty alcohol. Surfactants j catalogues are available which list a number of surfactants including nonionics, together with their respective HLB values.

The compositions according to the present invention comprise from 2 to 50 by weight of the total composition of said hydrophilic and hydrophobic nonionic surfactants, preferably from 5 to 40 most preferably from 8 to i WO 94129415 PCT/US94/06117 KF 6 The compositions according to the present invention may further comprise other nonionic surfactants which should K however not significantly alter the weighted average HLB i Ivalue of the overall composition.

The compositions according to the present invention further i comprise as an essential element an effective amount of H silicone compounds. By "effective amount" it is meant an amount of silicone compounds which is sufficient to reduce i i;and substantially eliminate the air bubbles generated in the t ~aqueous emulsions according to the present invention. By "effective amount" it is also meant an amount of silicone compounds which is sufficient to provide physically stable i' i aqueous emulsions wherein the viscosity can be conveniently i controlled. Preferably the compositions according to the i present invention comprise from 0.01 to 5 by weight of the total composition of said silicone compounds, more i ~preferably from 0.1 to 2 i Said silicone compounds reduce the viscosity of the aqueous emulsions herein whatever the viscosity was before the addition of said silicone compounds while increasing also ,physical stability. Preferred compositions obtained j according to the present invention have a viscosity of from 100 cps to 3000 cps at 50 rpm shear rate at 25 OC, more 3 preferably from 300 cps to 1500 cps, measured by a Brookfield :i ~DV II rotational viscosimeter.

Additionally, said silicone compounds substantially reduce and preferably substantially eliminate the air bubbles generated either during the manufacture of said emulsions or when pouring or shaking said emulsions, thereby providing aqueous emulsions which are acceptable for aesthetics and stability.

In industrial practice, the term "silicone" has become a generic term which encompasses a variety of relatively high-

J

SWO 94/29415 PCT/US94/06117 7 molecular-weight polymers containing siloxane units and I hydrocarbyl groups of various types. Indeed, silicone compounds have been extensively described in the art, see for Sinstance US 4 076 648, US 4 021 365, US 4 749 740, US 4 983 i 316, EP 150 872, EP 217 501 and EP 499 364. The silicone K compounds disclosed therein are suitable in the context of the present invention. Generally, the silicone compounds can j| be described as siloxanes having the general structure

R

i 00 R I00, 0 Preferred polydiorganosiloxanes are polydimethylsiloxanes having trimethylsilyl endblocking units and having a |1 .o 1 Viscosity at 25 0 C of fro 5 x 0- m 2 /s to 0.1 m 2 /s i.e. a value of n in the range 40 to 1500. These are preferred because of their ready availability., and their relatively low cost.

A preferred type of silicone compounds useful in the compositions herein is an alkylated siloxane of the type hereinabove disclosed in a mixture with solid silica.

The solid silica can be fumed silica, a precipitated silica or silica made by the gel formation technique. The silica particles can be rendered hydrophobic by treating twherem with diaklylsilyl groups and/or trialkysil2,, and whereoups eitach R ibonded pendently o can bthe sian alkyica or by means of silicone resadical. ExA preferred silicone compoundles of such Ssubstmixture comprisents are methyl, ethyl, propyobic, isobutyl, and phenyl I Preferred polydiorganosiloxanes are polydimethylsiloxanes I having trimethylsilyl endblecking units and having a I viscosity at 25°C of from 5 x 10 5 m2^/s to 0.1 m2/s i.e. a t| value of n in the range 40 to 1500. These are preferred i| because of their ready availability- and their relatively low 1-1 cost.

1 A preferred type of silicone compounds useful in the compositions herein is an ,y alkylated siloxane of the type hereinabove disclosed in a mixture with solid silica.

The solid silica can be fumed silica, a precipitated silica or silica made by the gel formation technique. The silica particles can be rendered hydrophobic by treating them with diaklylsilyl groups and/or trialkysilane groups either bonded directly onto the silica or by means of silicone resin. A preferred silicone compound mixture comprises a hydrophobic WO 94/29415 PCT/US94/06117 8 silanated, most preferably trimethylsilanated silica having a particle size in the range from 10 mm to 20 mm and a specific surface area above 50 m 2 Silicone compound mixtures employed in the compositions according to the present invention suitably have an amount of silica in the range of 1 to 30% (more preferably 2.0 to 15%) by weight of the total weight of the silicone compound mixture resulting in silicone compound mixture having an average viscosity in the range of from 2 x 104m 2 /s to 1m 2 Preferred silicone compound mixtures may i have a viscosity in the range of from 5 x 10 3 m 2 /s to 0.1m 2 Particularly suitable are silicone compound mixtures with a viscosity of 2 x 10-m 2 /s or 4.5 x 102m/s.

i, suitable silicone compounds for use herein are commercially i °0 available from various companies including Rhone Poulenc, SFueller and Dow Corning. An example of silicone compounds for use herein is Silicone DB R 100 commercially available from Dow Corning.

Formulating the compositions according to the present S "invention in an acidic pH range contributes to the stability I 'of the composition. The compositions of the present invention have a pH as is of from 0.5 to 6, preferably of S from 1 to 5. The pH of the composition can be trimmed by i all means available to the man skilled in the art.

Preferred compositions according to the present invention comprise hydrogen peroxide or a water-soluble source thereof.

Suitable water-soluble sources of hydrogen peroxide include perborate, percarbonate, persilicate and persulphate salts.

Hydrogen peroxide is most preferred to be used in the compositions according to the present invention. Typically, the compositions according to the present invention comprise from 0.5% to 20% by weight of the total composition of hydrogen peroxide, preferably from 2% to 15%, most preferably from 3% to i WO 94/29415 PCT/US94/06117 Preferred compositions according to the present invention further comprise a bleach activator. By bleach activator, it is meant herein any compound which reacts with hydrogen peroxide to form a peracid. In the case of bleach activators, such hydrophobic bleach activators typically belong to the class of esters, amides, imides, or anhydrides.

A particular family of bleach activators of interest in the present invention were disclosed in applicant's co-pending European patent application No 91870207.7. Particularly preferred in that family is acetyl triethyl citrate which was also disclosed in the context of bar soaps in FR 2 362 210.

Acetyl triethyl citrate has the advantages that it is environmentally friendly as it eventually degrades into citric acid and alcohol. Furthermore, acetyl triethyl citrate has a good hydrolytical stability in the product upon storage and it is an efficient bleach activator. As used herein and unless otherwise specified, the term bleach '4 activator includes mixtures of bleach activators.

j i In a preferred embodiment of the present invention, wherein the compositions comprise a bleach activator which is a hydrophobic liquid ingredient, the nonionic surfactant system jto be chosen to emulsify said bleach activator depends on the i HLB value of said bleach activator. Accordingly, a suitable i way to proceed is to determine the HLB value of the hydrophobic liquid ingredient (bleach activator), then select both the hydrophobic nonionic surfactants which have HLB values below said HLB value of said hydrophobic liquid ingredient and the hydrophilic nonionic surfactants which have HLB values above said HLB value of said hydrophobic liquid ingredient, wherein the difference in the HLB values of said hydrophobic and hydrophilic nonionic surfactants is preferably at least 3.

WO 94/29415 PCT/US94/06117 In a preferred embodiment comprising said bleach activator which is a hydrophobic ingredient, the emulsifying system meets the equation: %A %B SHLB(X) x HLB(A) x HLB(B) and 100%; 100 100 where X refers to the hydrophobic liquid ingredient to emulsify, A refers to one of said nonionic surfactants i (hydrophilic or hydrophobic), and B refers to the other said nonionic surfactant (hydrophilic or hydrophobic).

i In a particularly preferred embodiment of. the present i invention, wherein the compositions comprise Acetyl triethyl citrate with an HLB of about 10 as the bleach activator, an adequate nonionic surfactant system would comprise a i hydrophobic nonionic surfactant with an HLB from 1 to 10, and a hydrophilic nonionic surfactant with an HLB of above 11. A i particularly suitable system comprises a hydrophobic nonionic surfactant with an HLB of 6, for instance a Dobanol R 23-2 and a hydrophilic nonionic surfactant with an HLB of 15, for instance a Dobanol R 91-10. Another suitable nonionic surfactant system comprises a Dobanol R 23-6.5 (HLB about 12) and a Dobanol R 23 (HLB below All these Dobanol R surfactants are commercially available from Shell.

i Preferably, the compositions according to the present I invention are free of other surfactant types, especially anionic surfactants.

Depending on the end use envisioned, the compositions according to the present invention may further comprise a variety of other ingredients such as perfumes, dyes, optical brighteners, builders and chelants, pigments, enzymes, dye transfer inhibitors, solvents, buffering agents and the like.

r_ Y WO 94/29415 PCT/US94/06117 /i; The compositions according to the present invention are particularly useful as laundry pretreaters, i.e compositions which are dispensed and left to act onto fabrics before they are washed, or as laundry additives to be used together with detergents to boost their performance, or as dishwashing compositions to be used either in the dishwashing machines or by hand, or as hard surface cleaners, or as carpet cleaners to be used either by direct application onto the carpets or as detergent for carpet cleaning machines or also alone without detergents. The compositions according to the present invention are also particularly adapted to be used for delicate items.

The present invention further encompasses a process for the manufacture of the composition described herein. The process according to the present invention comprises at least three steps: In the first step, a hydrophobic mixture is prepared which comprises said hydrophobic nonionic surfactant and silicone compounds together with other hydrophobic ingredients which are to be formulated in the composition, such as perfumes, solvents, enzymes, bleach activators and polymers.

In the second step, a hydrophilic mixture is prepared which comprises at least said water, and said hydrophilic nonionic surfactant. Said hydrophilic mixture preferably further comprises other hydrophilic ingredients which are to be formulated in the composition such as dyes, optical brighteners, builders, chelants, hydrogen peroxide and buffering agents. In this second step hydrogen peroxide is preferably added last, after said buffering agent has been added.

Naturally, said first and said second steps can be performed in any order, i.e second step first is also suitable.

WO 94/29415 PCT/US94/06117 12 In the third step of the process according to the present invention, said hydrophobic mixture and said hydrophilic mixture are mixed together.

The present invention is further illustrated by the following examples.

Examples Compositions are made which comprise the listed ingredients in the listed proportions (weight Dobanol R 45-7 Dobanol R 91-10 Dobanol R 23-2 Hydrogen peroxide Acetyl trietyl citrate Brightener 49

R

S,S-ethylene diamino disuccinic acid Poly(4-vinylpyridine -N-oxide) Silicone DB R 100 Deionized water 6 3 6 7.5 7.0 0.20 0.10

II

6 3 6 7.5 7.0 0.20

III

6 3 6 0.20 0.10 0.10 0.10 0.10 0.10 0.10 0.50 balance------- Density at 30 0 C measured with a floating viscosimeter: Composition I Composition II Composition III: p 0.97 p 1.00 p 1.01 c rlQPPe I WO 94/29415 PCT/US94/06117 13 Viscosity measured with a Brookfield DV II viscosimeter with spindle RV/6.4 at 30 0

C:

Composition I 600 cps at 50 rpm Composition II 580 cps at 50 rpm Composition III: 530 cps at 50 rpm Compositions I to III are each made by preparing two mixtures. A hydrophilic mixture is prepared which comprises the water, the brightener, S,S-EDDS, poly(4-vinylpyridine-Noxide), the Dobanol R 91-10 and the Dobanol R 45-7. Hydrogen peroxide is added in said hydrophilic mixture as last step.

A hydrophobic mixture is prepared which comprises the acetyl triethyl citrate, Silicone DB R 100 and the Dobanol R 23-2.

Then said hydrophobic mixture is poured into said hydrophilic mixture, while mixing.

According to the present invention, the compositions II and III which comprise Silicone DB R 100 have a density which is higher than the density of the composition I which is free of any silicone compounds. In other words, the compositions II and III contain less air bubbles than the composition I.

Furthermore, by visual inspection it is also established that the compositions II and III contain less air bubbles than the composition I and are therefore more acceptable from a consumer viewpoint for aesthetic reasons.

Additionally, the compositions II and III (with silicone compounds) have a lower viscosity than the composition I which is free of any silicone compounds.

The above results surprisingly show that the use of silicone compounds in compositions according to the present invention reduces and substantially eliminates the air bubbles and also reduces the viscosity of said compositions. Additionally, the compositions according to the present invention which ~n~-I1P"-*~'C~;rrPS~C ~--gnc;s~ WO 94/29415 PCT/US94/06117 14 comprise silicone compounds are physical stable emulsions, even more stable than analogous compositions without silicone compounds.

)P

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Claims (17)

1. A stable aqueous emulsion having a pH of from 0.5 to 6, comprising at least a hydrophilic nonionic surfactant and at least a hydrophobic nonionic surfactant, wherein said aqueous emulsion further comprises an effective amount i of silicone compounds, wherein the level of the silicone compound i from 0.01% i to 5% by total weight of the emulsion.

2. An emulsion according to claim 1 wherein said silicone compounds are selected from siloxanes having the general structure: at aR i 0-) wherein n is from 20 to 2,000, and where each R independently can be a lower alkyl or phenyl.

3. An emulsion according to claim 2 wherein said silicone compounds are 20 mixed with solid silica. S4. An emulsion according to any one of the preceding claims wherein the level of the silicone compounds is from 0.1% to 2% by total weight of the emulsion. An emulsion according to any one of the preceding claims wherein the nonionic surfactant amount is from 2% to 50% by weight of the total emulsion.

6. An emulsion according to claim 5 wherein the nonionic surfactant amount is from 5% to 40% by weight of the total emulsion.

7. An emulsion according to either claim 5 or claim 6 wherein the nonionic i. surfactant amount is from 8% to 30% by weight of the total emulsion. C:WIVORDVMEUSSAVWLHONELE EPECM96 -94.DOC 16

8. An emulsion according to any one of the preceding claims wherein the hydrophilic nonionic surfactant has an HLB above 11 and wherein the hydrophobic nonionic surfactant has an HLB below

9. An emulsion according to claim 8 wherein the difference between the HLB values of the hydrophilic nonionic compounds and the hydrophobic compounds is of at least 1. An emulsion according to claim 8 or claim 9 wherein the difference I 10 between the HLB values of the hydrophilic nonionic compounds and the I hydrophobic compounds is of at least 3.

11. An emulsion according to any one of the preceding claims which further I comprises hydrogen peroxide or a source thereof and a bleach activator wherein S; 15 said bleach activator is emulsified by the nonionic surfactants.

12. An emulsion according to claim 11 which comprises from 0.5% to 20% by i weight of the total emulsion of said hydrogen peroxide. K i 20 13. An emulsion according to claim 11 or claim 12 wherein said bleach S' activator is acetyl triethyl citrate. I 14. An emulsion according to any one of the preceding claims which has a viscosity in the range of from 100 cps to 3000 cps at 50 rpm shear rate at 25 0 C.

15. An emulsion according to claim 14 which has a viscosity in the range of from 300 cps to 1500 cps at 50 rpm shear rate at 250C.

16. A detergent composition comprising an emulsion according to any one of the preceding claims. C:\WNWORD'MELISSAWLH\NODELETESPECI69615 4.DOC ^Arrcg^ -w 17

17. A process for preparing a stable aqueous emulsion according to claim 1, comprising at least three steps, including: preparing a hydrophobic mixture comprising said hydrophobic nonionic surfactant and silicone compounds together with other hydrophobic ingredients which are to be formulated in the composition, such as perfumes, solvents, enzymes, bleach activators and polymers; preparing a hydrophilic mixture comprising at least water and hydrophilic nonionic surfactant; mixing together said hydrophobic mixture and said hydrophilic mixture; wherein said steps and may be performed in sequence of either then or then

18. The process of claim 17 wherein said hydrophilic mixture further comprises other hydrophilic ingredients such as dyes, optical brighteners, builders, chelants, 15 hydrogen peroxide and buffering agents.

19. The process of claim 18, wherein said hydrogen peroxide is added last, after said buffering agent. 20 20. A stable aqueous emulsion according to claim 1, substantially as hereinbefore described with reference to any one of example compositions II and III.

21. A detergent composition according to claim 16, substantially as hereinbefore described with reference to any one of example compositions II and Ill.

22. A process according to claim 17, substantially as hereinbefore described with reference to any one of example compositions II and Ill. DATED: 2 June 1998 PHILLIPS ORMONDE FITZPATRICK Attorneys for: THE PROCTER GAMBLE COMPANY C:AWINWORDWELISSALHNCOELETE\SPECM961594.OOC C.kVVINWC)ROWELISSA LHWODELETE SPEC M965-9.DO p I~P1 r. a I i INTERNATIONAL SEARCH REPORT International application No. PCT/US94/06117 I A. CLASSIFICATION OF SUBJECT MATTER :C11D 1/82, 1/722 US CL :252/142, 174,174.21,174.22, DIG. 1 According to International Patent Classification (IPC) or to both national classification and IPC B. FIELDS SEARCHED Minimum documentation searched (classification system followed by classification symbols) U.S. 252/142, 174,174.21,174.22, DIG. 1 Documentation searched other than minimum documentation to the extent that such documents are included in the fields searched Electronic data base consulted during the international search (name of data base and, where practicable, search terms used) Please See Extra Sheet. C. DOCUMENTS CONSIDERED TO BE RELEVANT Category* Citation of d;.;ument, with indication, where appropriate, of the relevant passages Relevant to claim No. X US, A, 4,285,841 (Barrat et al.) 25 August 1981 col.3, 1-4 lines 45-50, col. 6, lines12-15 and line 57, col. 8, Examples 4-10 X US, A, 4,147,649 (Arnau et al.) 3 April 1979 col.4, lines 1-4 15-25, col. 5, lines 63-65, col.11, Table IV and col. 12 line Y US, A, 5,100,657, (Ansher-Jackson et aL) 31 March 1992 1-4 col. 3, lines 56-64, col. 17, lines 67-68 and col 18, lines 1- 14. Y US, A, 5,106,609 (BOLICH, JR., ET AL.) 21 APRIL 1992, 1-4 COL. 7, LINES 64-68, COL. 8, LINES 1-4, COL. 19, LINES

63-66. S Further documents are listed in the continuation f Box C. O See patent family annex. Special categories of cited documents: "T later document published after the international filin date or priority date and not in conflict with the application but cited to understand the documentdefining the generalstate of the at which i not considercd prinipte or theory nderltyin the invention to be of particular relevancer earlier document published on or after the international ring date X document of particular relevance; theclaimed invention cannot be considered novel or cannot be considered to involve an inventive step document which may throw doubts on priority claim(s) or which is when the document is taken alone cited to establish the publication date of another citation or other special reason (as specified) "Y document of puticula relevance; the claimed invention cannot be considered to involve an inventive step when the document i 0 document referring to an oral disclosure, use, exhibition or other combined with one or more other such documents, such combination meau being obvious to a person skilled in the art document published prior to the international filing date but ater thua document member of the same patent family the priority date claimed Date of the actual completion of the international search AUGUST 1994 Name and mailing address of the ISA/US Commissioner of Patents and Trademarks Box PCT Washington, D.C. 20231 Facsimile No. (703) 305-3230 Form PCT/ISA/210 (second sheet)(July 1992)* Date of mailing of the international search report SEP 08 1994 ,.~Le INTERNATIONAL SEARCH REPORT International application No. PCTIUS94/061 17 B. FIELDS SEARCHED Electronic data bases consulted (Name of data base and where practicable terms used): APS: search terms: hydrophilic (3a) nonionic, Hydrophobic (3a) surfactant, silicone or siloxane, dobanol (3a) (44-7 or 91- or 23-2) Form PCT/15A1210 (extra shect)(July 1992)* Ir i' i i jl Ii i f 1 I i i ::B j, i i i i i j I i" 1i i '4 i I; i i i i_ INTERNATIONAL SEARCH REPORT international application No. PCT/US94/56117 Box I Observations where certain claims were found unsearchable (Continuation of item 1 of first sheet) This international report has not been established in respect of certain claims under Article 17(2)(a) for the following reasons: 1. O Claims Nos.: because they relate to subject matter not required to be searched by this Authority, namely: 2. [l Claims Nos.: because they relate to parts of the international application that do not comply with the prescribed requirements to such an extent that no meaningful international search can be carried out, specifically: 3. Claims Nos.: 5-12 because they ar dependent claims and are not drafted in accordance with the second and third sentences of Rule 6.4(a). Box II Observations where unity of invention is lacking (Continuation of item 2 of first sheet) This Interiational Searching Authority found multiple inventions in this international application, as follows: 1. O As all required additional search fees were timely paid by the applicant, this international search report covers all searchable claims. 2. O As all searchable claims could be searched without effort justifying an additional fee, this Authority did not invite payment of any additional fee. 3. As only some of the required additional search fees were timely paid by the aplicant, this international search report covers only those claims for which fees were paid, specifically claims Nos.: 4. No required additional search fees were timely paid by ze1. applicant. Consequently, this international search report is restricted to the invention first mentioned in the clri i it is covered by claims Nos.: Remark on Protest D The additional search fees were accompanied by the applicant's protest. =J No protest accompanied the payment of additional search fees. Form PCT/ISA/210 (continuation of first sheet(l))(iuly 1992)*