Technical Field

The present invention relates to perfume additives for use in combination with fabric- softening compositions.

Background

Fabric-softening compositions to be added in the rinse step of a laundry cycle are well known.

The overall function of such compositions can be defined as the improvement of fabrics aesthetics/feel, after a wash cycle; this is why, in addition to softness, perfume delivery on fabrics from such compositions is an especially important aspect, and continuous efforts are made to improve such perfume delivery, so as to make it not only consumer-noticeable, but also long- lasting.

In EP-A-0 397 245 and EP-A-397 246 have been described perfume particles wherein perfume is dispersed within certain water-insoluble polymeric carrier materials, and the resulting particles are used in fabric cleaning or conditioning compositions. Not all perfume compositions, however, are compatible with said polymeric carrier materials.

It has now been found a simple and inexpensive carrier system for perfumes, which is fully compatible with any perfume, and is very convenient to use.

Such a carrier system consists of porous silica onto which a mixture, at specific ratios, of perfume and softening active is adsorbed.

The use of porous spheroidal silica per se as carrier for a wide range of material including perfumes, has been disclosed in EP-A-294 206, not relating to softening of fabrics nor any combination with softening active.

Summary of the Invention

The present invention relates to a perfume additive in granular form for use with fabric- softening compositions, containing :

- from 30% to 80% by weight of a mixture of perfume and softening active, in a ratio of perfume to softening active of 1:10 to 5:1, preferably 1:5 to 3:1

- from 20% to 70% by weight of porous silica on which said mixture of perfume and softening active is adsorbed, the particle size of the porous silica not exceeding 500 micrometers.

The present invention also encompasses the use of said additives as single doses during -use of fabric softening compositions, or the preparation of ready- to-use fabric softening compositions out of concentrates.

Detailed Description of the Invention

The porous silica

The porous silica useful herein is a precipitated spheroidal silica, having a particle size not exceeding 500 micrometers.

The silica herein typically has a pore volume in the range 25 to 75%. This silica is further characterized by a BET surface area* superior to 50m ² /g (DIN 66131) and a high absorption value. The absorption can be expressed as Dibutylphtalate (DBP) number, this DBP number should be above lOOg/lOOg, preferably above 200g/100g (DIN 53601, ASTM D 2414) .

Porous silica corresponding to the above specifications is available under the trade name Sipernat ^R from Degussa. The additives herein contain from 20% to 70% of porous silica.

The perfume/softening active mixture

The characterizing feature of the present invention is that perfume is mixed with a softening active before being adsorbed onto the porous silica.

* measured according to the method developed by Brunauer, Emmet and Teller (BET) , J. Amer. Chem. SOC. 60, 309 (1938) .

The ratio of perfume to softening active is from 1:10 to 5:1, preferably 1:5 to 3:1.-

Perfume, in the sense of perfume components or compositions of perfume components, can be any odorifirous materials or any materials which act as a alodour counteractent. The perfume will most often be liquid at ambient temperatures, but also can be liquified solid such as the various camphoraceous perfumes known in the art. The perfume can be relatively simple in composition or can comprise highly sophisticated, compact mixtures of natural or synthetic chemical components, all chosen to provide any desired odour.

Useful perfumes are those odorous materials that deposit on fabrics during the laundry process and are detectable by people with normal olfactory sensitivity. Many of the perfume ingredients along with their odor character and their physical and chemical properties are given in "Perfume and Flavor chemicals (aroma chemicals)", Stephen Arctender, Vols. I and II, Aurthor, Montclair, H.J. and the Merck Index, 8th Edition, Merck & Co., Inc. Rahway, N.J. Perfume components and compositions can also be found in the art, e.g. US Patent Nos. 4,145,184, 4,152,272, 4,209,417 or 4,515,705.

A wide variety of chemicals are known for perfume use including materials such as aldehydes, ketones, esters and the like. More commonly, naturally occurring plant and animal oils and exudates comprising complex mixtures of various chemical components are known for use as perfume, and such materials can be used herein. Typical perfumes can comprise e.g. woody/earthy bases containing exotic materials such as sandalwood

oil, civet and patchouli oil. The perfume also can be of a light floral fragrance e.g.- rose or violet extract. Further the perfume can be formulated to provide desirable fruity odours e.g. lime, limon or orange.

Particular examples of useful perfume components and compositions are anetole, benzaldehyde, benzyl acetate, benzyl alcohol, benzyl formate, iso-bornyl acetate, camphene, cis- citral (neral) , citronellal, citronellol, citronellyl acetate, paracymene, decanal, dihydrolinalool, dihydromyrcenol, dimethyl phenyl carbinol, eucalyptol, geranial, geraniol, geranyl acetate, geranyl nitrile, cis-3-hexenyl acetate, hydroxycitronellal, d-limonene, linalool, linalool oxide, linalyl acetate, linalyl propionate, methyl anthranilate, alpha-methyl ionone, methyl nonyl acetaldehyde, methyl phenyl carbinyl acetate, laevo- enthyl acetate, menthone, iso-menthone, myrcene, myrcenyl acetate, myrcenol, nerol, neryl acetate, nonyl acetate, phenyl ethyl alcohol, alpha-pinene, beta-pinene, gam a-terpinene, alpha- terpineol, beta-terpineol, terpinyl acetate, vertenex (para-tertiary-butyl cyclohexyl acetate) , amyl cinna ic aldehyde, iso-amyl salicylate, beta- caryophyllene, aldehyde, iso-amyl salicylate, beta-carophyllene, cedrene, cinnamic alcohol, coura in, dimethyl benzyl carbinyl acetate, ethyl vanillin, eugenol, iso-eugenol, flor acetate, heliotrophine, 3-cis-hexenyl salicylate, hexyl silicylate, lilial (para-tertiarybutyl-alpha- methyl hydrocinnamic aldehyde) , gamma-methyl ionone, nerolidol, patchouli alcohol, phenyl hexanol, beta-selinene, trichloromethyl phenyl carbinyl acetate, triethyl citrate, vanillin, veratraldehyde, alpha-cedrene, beta-cedrene, C ₁₅ H ₂ 4sesquiterpenes, benzophenone, benzyl salicylate, ethylene brassylate, galaxolide (1,3,4,6,7,8-hexahydro-4,6,7,8,8,-hexamethyl-

cyclo-penta-gamma-2-benzopyran) , hexyl cinnamic aldehyde, lyral (4-(4-hydroxy-4-methyl phenyl)-3- cyclohexene-10-carboxaldehyde) , methyl cedrylone, methyl dihydro jas onate, methyl-beta-naphthyl ketone, musk ambrette, musk idanone, musk ketone, musk tibetine, musk xylol, aurantiol and phenylethyl phenyl acetate.

The softening active for use in the perfume additives herein can be selected from the group of di-long chain quaternary ammonium compounds, di- long chain imidazoline compounds, di-long chain quaternized imidazoline compounds, as well as certain mono long-chain alkyl quaternary ammonium compounds and mono long-chain alkyl amines.

Di-long chain quaternary ammonium compounds are of the formula :

wherein R*-_ and ₂ are C*L_4 saturated alkyl groups or hydroxyalkyl groups and R ₃ and R ₄ are acyclic aliphatic Cg_ ₃ o, preferably Cι ₂ - ₂₃ . more preferably C*j_5_22 hydrocarbon groups which may be intempted by ester linkages, and A is an anion.

Preferred are compounds of the formula above wherein R^ and R2 are methyl groups, and R ₃ and R ₄ are derived from fatty materials such as tallow.

Preferred compounds of the formula above for use herein include the well known ditallowdimethyl ammonium chloride (DTDMAC) , ditallowdimethyl ammonium methyl sulfate, and di(hydrogetated tallow)dimethyl ammonium chloride.

Compounds of the formula above wherein R3 and R4 are interrupted by ester groups are.disclosed in EP-A-239 910; such compounds have the advantage of being more rapidly biodegradable than the above-described compounds; preferred is N,N di(2- tallowyloxy-2-oxo-ethyl)N,N dimethylammonium chloride.

Di-long chain imidazoline compounds are of the formula

(CH ₂ )m

/ \

N N - X - R

*ι

wherein m is an integer from 2 to 4, preferably 2, and R*j_ and R ₂ are, independently, a ₈ "" ^c ₃₀ al yl or alkenyl, preferably Cι -C _2u alkyl, more preferably C^-C^ _Q alkyl, or mixtures of such alkyl radicals. Examples of such mixtures are the alkyl radicals obtained from coconut oil, "soft" (non-hardened) tallow, and hardened tallow;

X is - R ₄ - T - C -

4 wherein T is O or NR5, R5 being H or ^ ^ alkyl, preferably H, and R4 is a divalent C.-C ₃ alkylene group or (C H4θ)* _m , wherein is a number of from 1 to 8; or X is R4.

Most preferred imidazoline actives of the formula above are of the following formulae :

la lb

N r\N—(CH ₂ )2—NH-C—Ri and N —(CH ₂ )p —C—R- _j _ i

Ri Ri

wherein R-^ is a tallow group.

Compounds of formula la are ditallowimidazolines, while compounds of formula lb are ditallowimidazoline esters.

Quaternized di-long chain imidazoline compounds are of the formula :

or

or mixtures thereof, wherein R and R ¹ are, independently, CH-C21 hydrocarbyl groups, preferably tallow, R ² is a C-L-C ₄ hydrocarbyl group, preferably

methyl, A is an anion, m is an integer from 2 to 4, preferably 2 and X is R ₄ - T - C -

0 wherein T is O or NR ₅ , R ₅ being H or C±-C^ alkyl, preferably H, and R ₄ is a divalent C-1-C ₃ alkylene group or (C ₂ H4θ) _:m , wherein m is a number of from 1 to 8; or X is R4. Preferably, T is O and R is (CH2) ₂ (quaternized ditallow imidazoline ester) .

Mono long-chain alkyl amines useful herein include compounds of the formula R- _j _ - N - R2

R ₃ wherein R*L is a Cg_ ₃ o acyclic aliphatic , preferably C.2-2 ₃ hydrocarbon group which may be intempted by ester linkages, 2 and R3 are Cι_4 saturated alkyl groups or hydroxyalkyl groups of the formula (CH ₂ CH2θ) _n H where n is an integer from 1 to 5.

They further include monotallowimidazolines of the formula (CH ₂ )m

N N - X - H

C

Rl wherein R-^ is a C ₈ _ ₃₀ alkyl or alkyl group, preferably Cι ₂ _ _2u , more preferably C^^ _^ ^Q J m is an integer from 2 to 4, preferably 2 and

X is R - T - C - O o wherein T is O or NR ₅ , R ₅ being H or C^-C^ alkyl, preferably H, and R ₄ is a divalent C-L-C ₃ alkylene group or (C ₂ H4θ)m, wherein m is a number of from 1 to 8; or X is R4.

Mono alkyl quaternary ammonium compounds useful herein include compounds of the formula

wherein R-^ is an acyclic aliphatic Cg- ₃₀ , preferably C. -22 hydrocarbon group which may be interupted by ester linkages, R2, R ₃ and 4 are C ₁ _4 saturated alkyl groups or hydroxyalkyl groups; and A is an anion.

A preferred mono-alkyl ammonium compound for use herein is cetyl trimethylammonium bromide.

The mono long-chain alkyl amines and mono long-chain alkyl ammonium compounds are preferably used in combination with the di-long chain alkyl ammonium or imidazolines described hereinabove.

Most preferred softening actives for use in the additives herein are ditallowdimethyl ammonium, ditallowimidazoline ester, quaternized ditallowimidazoline ester, and mixtures thereof.

Optional ingredients

The present additives may contain additional ingredients, which can be pre-mixed with the perfume and softening active before they are adsorbed onto the porous silicate, or added, after the adsorption is completed, to the particles.

Ingredients which can be pre-mixed with the perfume and softening active are selected from the group of

- sythetic and natural waxes

- synthetic and natural fats

- synthetic and natural mono, di and tri esters

of polyols with C ₈ -C ₂₂ carboxylic acids or mixtures thereof

- C ₈ _ ₂₂ alcohols, ethoxylates thereof and esters thereof with C ₁ - ₄ carboxylic acids

- dyes

Ingredients which can be added to the particles after adsorption is complete include water-soluble coating materials/agglomerating materials and dyes

Preferred ingredients to be pre-mixed are the esters of C8-20 alcohols, in particular glyceryl monostearate.

The water-soluble coating/agglomerating materials can be selected from the group of polyvinyl alcohol, polyethylene glycol, sugars, polyacrylamides, polysaccharides and similar natural and synthetic polymers.

Dyes are typically used and can be added to the mix before adsorption onto silica, or sprayed on the formed particles as a last step.

Method of preparation of the additives herein

A co-melt of the softening active and the perfume is typically made, possibly including an optional ingredient such as listed above.

The co-melt is adsorbed on porous silica, keeping the temperature, needed to keep the co-melt liquid, typically at 50"C; Adsorption can be achieved by adding the co-melt in portions to the pre-heated porous silica under agitation, or by spraying it on pre-heated porous silica in a "Nauta" type mixer.

The resulting free-flowing powder is cooled to a temperature ranging from 3'C to ambient, and sieved on an appropriate sieve (e.g. Mesh 22) ; the powder is then agglomerated in an agglomeration unit, such as a Plough Share Lodige, possibly with the addition of a coating/agglomeration material; the agglomerate is cooled and sieved over an appropriate sieve (e.g. Mesh 22) .

Use of the perfume additives herein

The perfume additives herein can either be used as single-dose additives for fabric softening compositions, during use, or as additives in the preparation of fabric-softening compositions out of concentrates, before use.

Preferably, the present additives are used as single-dose additives to unperfumed fabric softening compositions during use; i.e. a dose of additive sufficient for a typical washing machine load is added to unperfumed fabric softening composition, prior to the rinse cycle of the laundry process.

Such an addition can conveniently be made in the dispenser of automatic washing machines; i.e. before starting the laundry cycle, an amount of fabric softening composition in liquid form is first poured into the dispenser of the washing machine, and the specific dose of perfume additive in granular form is added to said fabric softening composition sitting in the dispenser, and is dispersed therein.

The resulting mixture is then brought into contact with the fabrics, during the rinse cycle and the perfume is released onto the fabrics.

The use of the perfume additives herein is not limited to liquid fabric softening compositions since their granular form would render them quite suitable

for use in combination with fabric-softening compositions in particulate form; such fabric- softening compositions can be used as is, or diluted with water before use.

When used as such single-wash doses, the present additives can conveniently be packaged into single- dose sachets containing the powdered additive, such sachets being made available to the consumer in the form of boxes containing several of them, said sachets containing either the same perfume, or different perfumes so as to allow the consumer to choose the perfume to be left on the laundered fabrics, for each laundry cycle.

The following examples illustrate the invention and facilitate the understanding.

The following granulates are prepared, according to the method described above (with cooling temperature of 4 ^* C).

Percentage bv weight

Ingredients Fv. _l Ex.ll Ex. Ill Ex.IV Ex.V Ex.VI Ex. VII Ex. VIII Ex. I

p _erfurne 13% 47% 20% 20% 20% 30% 20% 20% 15%

Dittalσw Dimethyl ammonium 54% 20% 15% 24% - - - - - chloride

Ditta-ow -midazoiine ester . . . . 47% 30% 27%

CTAB (CetyITrimethyl

Ammonium Bromide) . . . . . . . 14% ^** n%

Giyceryi monostearate* - - ^{10% 23%} - - - - -

Sorbitaπ distearate* . . . . - - . . 25%

S ica Sipemat ^R 50 33% 33% 40% 33% 33% - - 34% -

Silica SipematR22 40% 33% - 50%

Polyethylene glycol 4000** - 15% - - 20%

T0 ₈ (Taliowalcoho. 8 times ethoxylated)* - - - - - - - 32%

* added in the pre-mix

** sprayed onto formed particles

Dye is sprayed onto the above granulates; the formed granulates are used as perfume additives for fabric softening compositions.