891

LlPOSOMES

Finding new uses for Iiposomes in cosmeticsThis article 011 "The Use of Lipa-somes in Cosmetics" was prepared byGeoffrey J. Brooks of Brooks indus-tries IIIC., and Robert C. McManus ofChemmark Development Inc. Bothfirms are located ill SOIllIl Plainfield.New Jersey.

Liposomes are an increasingly pop-ular delivery system and have beenthe subject of much research in themedical and cosmetic areas. IIseems thai almost every other newtreatment cosmetic now features aliposomal delivery system of somedescription. This is especially truein Europe, where nearly all themajor cosmetic companies, includ-ing L'Oreal, Lancome, ChristianDior, Payol and Lancaster, haveproducts containing liposomes.Their use is catching on in the Unit-ed States where companies such asAvon, Elizabeth Arden, Estee Laud-er and Shaklee are launching newproducts containing Hposomes. Inthe Far East, companies such asPola have had cosmetics with Hpo-somes for some years. In Japan, thegovernment has just issued a seriesof proposed regulations to ensurethat not only are the liposomes pres-ent in the formulation, but arestable for at least three years. Thefollowing is an overview of lipo-somes' use in the cosmetic field.

Llposomes are hollow vesicles, gener-ally formed by phospholipid bilayers.that are similar to the lipids thai are amajor component of cell walls (Fig.I). An easy way to describe liposomesis to think of thcm as empty cells inwhich you can program the contents.

Why after all this time since their"discovery" in the early 1960s byBangham (I) have they now becomeso popular? The most important rea-son is that techniques are now avail-able to produce stable Iiposomes.When these interesting hollow parti-cles were First observed. they werestable for only short periods of time.This made it difficult to use them inany practical product. Interestingly.Bangham was able to field a patent

issued to IG Farben in 1935 (GermanPatent 417,715) for placing drugs in adepot for slow release made by mak-ing a lecithin/cholestrin emulsion.Back then, the tools for observingwhat one had made were not as welldeveloped as today-hence theirnondiscovery.

The initial excitement created bythe discovery of hollow emulsions.and the means to make them, did notgo unnoticed by cosmetic scientists.However. their instability seemed topreclude their use. Further workresulted in a patent issued to Unilever

Phospholipid

FIG. I.Liposome cross section.

others on their nonionic liposomes (2).This work reponed that. "Emulsions.both milks and creams, offer strikingexamples of the traditional approachthat has been paralyzing the cosmeticindustries for several centuries" andthat "(emulsified) oils have a numberof disadvantages without offering ...any advantages as far as the elasticityof the skin is concerned." Not surpris-ing. L'Oreal has since launched awhole series of successful cosmeticsbased on their patented technology(U.S. Patent 4,217,344) for makingliposomes called "Niosomes."

Christian Dior has a processingpatent to make liposomes based oncombinations of lecithin and choles-terol utilizing cosmetic ingredientssuch as collagen and elastin peptides(French Patent 2.251,565) (3). In apaper presented at the InternationalFederation of Societies of CosmeticChemists in 1986, Christian Dlor pre-sented data showing how ingredientscould be delivered more effectively tothe skin (4) by Hposomes and they use

•Techniques are currentlyavailable to produce stableliposomes

(Oleniacz) in 1976 (U.S. Patent3,957.971) citing advantages for mois-turizing the skin, which included Hpo-some substantivuy to the skin, im-proved adsorption of atmosphericwater and, most importantly, theenhanced delivery of encapsulatedwater, moisturizing agents and lipids.

The commercialization of cosmeticliposomes was obviously close whenL'Oreal's basic research departmentwork was presented at the lnternation-al Federation of Cosmetic Scientistsmeeting in 1978 by Handjani-Vila and

FIG. 2. Sketch shows differences between munuammetar, unilamellar liposomes

INFORM. Vol. 1. no. 10 (October 1990)

892

CH2 OCO-RI

CHOCO-R 0I •CH2 a ~P - OCH2 CH2N. (CH3h

"o

LlPOSOMES

these results in the promotional litera-ture for "Capture."

There arc two types of liposomes(Fig. 2) which have been producedcommercially: multilamellar and uni-lamellar. The unilamellar types arcprodcuced as hollow particles rangingin size from 30---150 nm (0.03-0.15microns) using a Microfluidizer, Thispatented homogenizer. which workson a submerged jet principle. bringstwo streams of t1uid together in pre-cisely designed rnicrochannels withinthe mixing chamber under pressuresapproaching 20,000 psi (5). Liposomebilayers are formed due 10 the energyinput.

Even though large bilipid mem-branes exist in nature, lt seems tomake sense from an intellectual view-point that packing of the lipids wouldbe optimized in small uniform vesi-cles. These would be more difficult todisrupt; the coalescing of the dropletswould occur more slowly. In fact, vonSmoluchowski equations for the ratesof flocculation hold that the smallerthe droplet. the slower the coales-cence. and. consequently. the greaterthe stability of the system (6). Theuniform small unilamellar liposome(7) will be the subject of the remain-der of this article.

There are two types of cosmeticliposomes=-emulsion and dispersion.Both types exist with a tightly con-trolled panicle size distribution, and80% of the particles present are within10% of the mean particle diameter.Emulsion liposomes capture an oilyactive in the lipid bilayers, forming apan of the liposomal structure. Gener-ally speaking these llposomes have aslightly larger particle size, runningfrom 100-150 nm. In the other type,dispersion liposomes, the active iswater-soluble. and capture of theactive occurs in the hollow core of theliposorne. Dispersion liposomes havea particle size of 50-100 nm.

From work by Esmail Tabibi atMedi Control Corporation it is possi-ble to calculate the capture rates forthe two different types of liposomes.making the following assumptions:

(a) The particles are spherical(freeze/fracture scanning electronmicroscope (SEM) pictures confirmthis).

(b) The distance between the twoadjacent layers (in the bilayer) isassumed to be 50 A.

(c) The area occupied in the struc-rure of the layer by one molecule ofphospholipid is assumed to be 65square A.

(d) The phospholipids are tightlypacked and fill up the available spacein the bilayers of the spheres.

(e) The liposomes are unilamellarand all the same size with an averagediameter (D) of 70 nm (700 A).

(f) The average molecular weightof the phospholipid is 800 daltons.

Therefore, the number (n) ofmolecules in each Hposome is:

n = 2CD-50>65

where D is sphere diameter in A and n= 30,820 molecules of phospholipid ina liposome.

The weight of phospholipid in eachIiposome (w) is then calculated as:

w =. 30820 X. 800 = 4.0 X 10·17g.6.023 x IQ23

If 10% phospholipid is used in thepreparation of the liposome, then 0.1 gis in I mL of liposome. The numberof unilamellar liposomes in I mL ofthe liposome will equate 10 2.5 x10 15; therefore each gram of phos-pholipid will create 2.5 x 1016 lipo-somes. Each liposome will theoreti-cally have 1.1 x 108 cubic A. of aque-ous capturing ability (i.e. the center ofthe \iposomes) and, hence, I g ofphospholipid bilayer will capture 2.75mL of aqueous solution and 1.675 mLof"oi1" in the bilayer.

As the calculations show, a lipo-some is a large complex structure witha molecular weight of 25 million.

Lecithin: building blockOne of the keys to making liposomesis lecithin, an interesting, if somewhatignored, cosmetic material in irs ownright. Lecithin, described in the MerckIndex as a phosphatide found in allliving organisms, is a naturally occur-ring mixture of the diglycerides ofstearic, oleic and palmitic acids, linkedto the choline ester of phosphoric acid(molecular structure, see Fig. 3).

The fatty acid distribution of soy-bean lecithin is reponed as: palmitic.

FIG. 3. Ledthin molecular structure.

11.7%; stearic, 4.0%; palmitoleic,8.6%; oleic, 9.8%; linoleic, 55.0%;linolenic, 4.0%; arachidonic, 5.5%;plus other C:20 and C:22 acids.

Lecithin is a waxy mass when theacid value is around 20 and fluidwhen the acid value is 30. Freshlymade lecithin is while in color. butrapidly becomes yellow to brownwhen exposed to air. Lecithin is insol-uble in water, but swells to form a col-loidal suspension. When formulatedinto cosmetics, it imparts a nice feeland shine. In early use, lecithin wasunstable and caused color changes andrancid notes in cosmetic formulations.For these reasons, lecithin was notwidely used by formulators, or wasincorporated at low levels. Today abeuer understanding of both lecithinchemistry and the importance of topi-cally applied essential Iany acids(which represent more than 60% oflecithin) have given this material anew life. This natural phospholipid ismuch more bioavailable and skin-lipidcompatible than the popularly usedtriglyceride oils. Now, liposomesbased on lecithin give formulatorsnew opportunities to use this verybasic and functional skin and hair careingredient. Today high-quality plant-derived lecithin contains high levelsof phosphatidylcholine and has excel-lent color and odor stability.

Stability testingLiposome stability and shelflife can bedetermined by stability of particle sizeas measured by a Brookhaven B190particle size analyzer. If panicle sizeremains essentially unchanged overlime, through freeze-thaw cycles andat various temperatures, then the lipo-some is stable. Liposomal disper-sions-lecithin and Panthenol/liveyeast cell derivative (LYCD) andlecithin-and liposomal emulsions-lecithin and tocopherol/lecithin andsqualene---have been evaluated under

INFORM,Vol. 1. no. 10 (October 1990)

------------------------- ------------------------------------893

LlPOSOMES

the following conditions: (a) 4O"C for3 months, (b) 50·C for one month, (c)freeze/thaw for three cycles (-20/+4O"C). Results of the particle size anal-ysis on aging are shown in Table 1.

The stability samples were kept inthe dark. There were very few differ-ences in appearance between the sta-bility samples and freshly made sam-ple production. A slight darkening incolor was noted in the high-tempera-ture samples and in the two-year roomtemperature samples. The change inodor, which is bland initially, was alsovery slight. A slight separation ofunencapsulated oil was noted on thetwo liposomal emulsions. Assays onsamples containing active ingredientssuch as the LYCD. tocopherol acetateand superoxide dismutase showed nochange. II has been suggested thatencapsulation of an active in a lipo-some will promote additional stability(8). Work is in progress with a retinyl-palmitate liposome at high tempera-tures in a cosmetic formulation to testthis theory.

Advantages in formulationsEnhanced penetration into the dermis.This has been reported in patentsissued both to Unilever and toL'Oreal. L'Oreal was able to showenhanced penetration by using bothfluorescent techniques and radiola-beled sodium (CI4) pyrrolidone car-boxylate (9).

Enhanced bioavailability af active/0 living cells. Work reported byChristian Dior indicates a doubling offibroblast activity and a fourfoldincrease in wound healing when pep-tides are applied in the liposome Connvs the free form. Either enhancedbioevaltability or penetration of theactive into the living cells (4) is thelikely reason for these results. Prod-ucts with this type of activity comevery close to being designated asdrugs. A recent paper published byresearchers from Lilly concerningvitamin A palmitate indicates that thismaterial works in a similar way torebuild the skin when applied topical-ly (13). Vitamin A palmitate has beenused in a myriad of cosmetic vehiclesand commercial products over theyears. reviewed exhaustively for itstopical safety by the CIR in the United

TABLE 1

Particle Size Analysis on Aging (in nm)

Inilial 40'C

Lecithin/PanthenolLecithin/L YCDLecithin/tocopherolLecithin/squalene

5610812.160

61112127168

50'C rrr 2 )"r

58 62 55105 115 110131 125 13516. 168 166

States and is now available in liposo-mal fonn.

Other topical application benefitshave included: (a) a nice, elegant feelon the skin; the phospholipids in theliposomaJ form seem to have the abili-ty to promote soft, supple skin (2); (b)excellent substantivity to keratin (skinand hair); moisturizers encapsulated in

a ABSORBEDllPOSOME

.'.••••

liposomes have been shown to beresistant to washing and to removalfrom the skin (U.S. Patent 3.957,971)(2); (c) improved water absorptionover a longer period of time-a"timed-release" effect; (d) preferentialdelivery of moisturizer to the criticallydry or damaged part of the skin (Ole-niaez U,S, Patent 3,957,971); and (e)

rIG. 4, Liposome resorption process.

b llPOSOMEUNDERGOINGENDocYTOSIS

UNDIGESTEDPARTICLESEXCRETED.::..

•....."('--.,'UPIDS EXCRETEO -

BV lVSOSOME

C llPOSOME UNDER-GOING UPIDEXCHANGE

INFORM, Vol. 1,no. 10(October 1990)

894

LlPOSOMES

Formulating with IiposomesFollowing four simple rules willensure that one can make elegant. sta-ble, functional cosmetics containingliposomes. The ingredients that canbe used are limited by the dynamicnature of the liposomal vesicles, butthis can offer the formulator theopportunity to make a "focussed" for-mula. In the marketplace such"niche" formulations have been verysuccessful.

The four rules are:First, avoid surfactants. and materi-

als that can act as a cosolvent for thephospholipid, e.g. powerful anionicsand nonionies.

Second. avoid materials with highionic strength. such as salts. as these

reduction of the toxicity of irritatingmaterials (8).

10.0%; polysorbate 80. 0.5%: sorbi-tant monooleate. 0.5%; and water.89.0%. The emulsion, made byhomogenization, was a stable, flow-able cream.

A mixture of 10% of the liposome(an oily active squalene) and a water-soluble active Panthenol was added 10this emulsion with gentle stirring. Theformulations were kept at room tem-perature for one month. SEM pho-tographs were taken and in the photosliposomes could be seen as craters andspheres. Oil droplets appeared as flatand stippled circles.

This work demonstrated that lipo-somes are stable when incorporatedinto a mineral oil lotion and that theycan be found easily.

Modes of actionThere are two main theories as to howliposomes work, and this is an area ofcontroversy. The first theory describesa mechanical type of action where theoily lipid bilayer material breaksdown and forms an occlusive film onthe surface of the skin, which thendrives the active deep into the epider-mis, leaving the liposome on the sur-face of the skin. However, someresults reponed for Iiposomes in gen-eral are far too good to be explainedentirely by this mechanism. A morerecent theory. based on further study.says that the topical application ofliposomes leads to the regeneration ofpermeability barrier of the skin bybuilding up the surface phospholipidsthat protect the skin from environmen-tal influences. From this surface lipo-somal layer, the liposomes penetrateinto the stratum corneum where theyfonn lipid lamellae and their contentsare integrated into the multi lamellarlipid membranes of the skin fonningthe permeability barrier (10). Otherinvestigative methods have includedintravenous injection of liposomeswhereby the package is delivered bysome son of interaction with the cell.A resorption of the liposome's lipidmembrane fuses with the cell wall as aresult of the similarity of their bilayerstructures (11,12). Another theorystates the intact Iiposome is engulfedby the cell and the contents mergewith the cell cytoplasm. Figure 4 illus-trates the resorption process (II).

Formulation I

Ingredient Source Percent

69.05(I) 0.30(1) 7.50

0.10

Demineralized waterVeegumCarbopol 941 (2%)Tetrasodium EDTAGermaben u

WaterMagnesium aluminum silicateCarbomerTetrnsodiumEDTAPropylene glycol anddiazolidinyl urea andmethylparaben andpropylparabenGlycerineCetearyl alcohol andceteareth- 20Sorbitan stearateStearic acidGlyceryl stearateCetearyl alcoholCetyl alcohol andacetylated lanolinalcoholC12_15 alcohols benzoatePPG-12 stearyl etherDimethiconeMineral oil 70 vis.Potassium hydroxideSoy lecithin and tissuerespiratory factorsFragrance

(3) 1.003.00Glycerine

8rookswax D(4)(5)

0.800.500.501.001.40

Liposorb SCStearic acid XXXLipoGMSCetearyl alcohollvarbase 3210

(5)

(5)(6)(7)(8)

0.500.400.400.203.000.15

Finsolv TNAralmol ESilicon SFI040Mineral oilPotassium hydroxideDermasome TRF

Demonstrating presenceFrom a quality control viewpoint, themeasurement of panicle size will giveadequate verification that unilamellarliposomes have been formed. Thecommonly accepted method fordemonstrating that the vesicles arehollow is to freeze-fracture the prepa-ration and lake scanning electronmicrographs. As this is a relativelyexpensive procedure, it is not used forroutine quality control.

Liposomes were added to a verysimple emulsion to see if they couldbe detected in a cosmetic formulation.The formula consisted of: mineral oil.

(9)(lO)

10.000.20Fragrance

Procedure: Heat water to 70'C and disperse the Veegum in side tank. Add Carbopolsolution, EDTA, Gennaben and glycerine. Melt oil phase ingredient in main tank at75'e. Add water phase to oil phase and mix until unifonn and creamy. Add KOH andmix thoroughly; begin cooling to 50·C. Add fragrance and homogenize. Add Derma-some TRF and cool to 3Q0e.Sources: (I) R.T. Vanderbilt Inc., (2) B.F. Goodrich Inc.. (3) Sutton Laboratories Inc.. (4)Brooks Industries rnc.. (5) Lipo Chemicals Inc., (6) Pmetex lnc., (7) ICI Americas Inc..(8) GE Silicones Inc.. (9), ChemMark Developments Inc.. (10) Noverome Inc.

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LlPOSOMES

will completely destabilize the lipo-somes.

Third. avoid solvents that willremove the water that stabilizes thesurface of the phospholipid bilayer.e.g., greater than 5% alcohol.

Fourth. avoid excessive sheer. Thebest way to add Iiposomes to your for-mula is to stir them in gently after theformula is essentially made, at as lowa temperature as possible (under45+C). just after the perfume and anyother heal-sensitive ingredients beingused. The formula should nOI behomogenized.

The recommended use levels of theliposomal system in cosmetics are5-15%.

Lecithin is compatible with mineraloil and commonly used cosmetic oils.such as esters, triglycerides. mineraloil: under normal conditions such oilsdo not destabilize the liposomal struc-tures in a cosmetic formulation. Thisis because, in the liposome form.lecithin is highly hydrated and thewater is intimately associated with thebilipid membrane structure. There-fore, before an oil can dissolve theliposorne, the water of hydration hasto be removed, either by heat (therefined lecithin has a transitional tem-perature of around 6(YC) causing thelecithin to "melt" and expel the waterwhich forms a pan of the hydrophilicportion of the molecule, or, by exces-sive shear.

Basic comparibifiry studies wererun with commonly used cosmeticingredients at levels typically found incosmetic formulations. Results showexcellent compatibility and stabilitywith glycerine (10%); propylene gly-col (5%); polysorbate 20 (I %);ethanol (5%); and 5% of each type ofthe two liposomes. the balance beingwater. There was no compatibility atall with 1% salt solution and 1% sodi-um lnuryl sulfate with either liposome.Polysorbate 20 at 5% improved clan-ty, reducing panicle size of the lipo-some with Panthenol, suggesting thatthe liposomes were being convertedfrom their bilayer structure into amicellar structure.

The following formulations repre-sent liposomal delivery systems thatwere formulated in accordance withthe above guidelines. They show

Formulation 1

ingredient eFTA nomencknure

87.200.30

Demineralized waterCarbopol 1342Brookswax D

WaterCarbomerCeteareth-20 and cerearylalcoholC12_1S alcohols benzoateGlycerineAminomethylpropanolPropylene glycol and diazolidinylurea and methylparaben andpropylparabenLecithin and retinyl palmitateLecithin and tissue respiratoryfactorsFragrance

Source

FmsolvTNGlycerin USPAMP 95Gennaben II

Fragrance

(2)

(4)(6)

1.002.002.000.40

(3)(9)

1.003.00

3.000.10

Procedure: Disperse the Carbopol in cold water and heat to 70'C. Blend the Brookswaxand Finsclv at 70'C and add with rapid agitation. Acid the glycerin. AMP and Gennabenand mix until uniform. Cool to 4S'C with sweep agitation. Add the fragrance and Derma-somes. mixing gently until uniform. Continue cooling to 35'C and adjusl pH 10 6.5 or asrequired.

Sources: (2) B.F. Goodrich Inc .. (3) Sutton Laboratories Inc .. (4) Brooks Industries Inc ..(6) Ftoetex Inc .• (9) ChemMark Developments Inc.

Formulation 3

Ingrtdient eFTA nomenclature Source Percent

65.00(4) 15.00

2.00

(4) 1.00(6) 2.00(12) 0.50

(3)(4)

1.000.30

Demineralized waterCarbopol 1342 (2%)GlycerineBrookswax D

WaterCarbomerGlycerineCetearyl alcohol andceteereth-znCI2_IS alcohols benzoateDimethiconepropylene glycol anddiazclidinyl urea andmethylparaben lindpropylparabenSelenium PolypeptidesLecithin and superoxidedismutaseLecithin and tocopherylacetateAminomethylpropanol

(9)

(9)

10.00

3.000.20

FinsolvTNOC 200 Fluids 350 csGennaben II

Biomin Se/P/CDermasome SOD

DermasomeE

AMP

Procedure: Disperse the Carbopol in water while heating 10 75'C. Add the glycerine andmix well. Blend the Finsclv TN. Brookswax D and dimethicone at 70'C until unifonnand add to water phase: mix until unifonn. Add the AMP and mix umil uniform with fastpropeller agitation. Cool to 50'C and add the Biomin Se/p/C and Germaben with sweepagitation. Cool to 35"C and add the Dennasomes. Fragrance as desired and mix well.Adjust pH to 5.0 with citric acid if required.

Sourcu: (3) Suncn laboratories Inc•• (4) Brooks Industries Inc .• (6) Fmetex Inc .. (9)ChemMarIr: Developments Inc .• (II) Kelco Inc., (12) Dow Coming Inc.

INFORM. Vol. 1,no. 10(October 1990)

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LIPOSOMES

acceptable stability and have beenwell received by user groups.

Facial lotion with a tiposome con-taining LYCD (Formulation I). A testthat included several panelists was car-ried our comparing the liposome fonnof LYCD to the same fonnula contain-ing 0.7% LVCD. All of the panelistsnoticed a difference right away as theliposomal formula gave a perceptiblyfaster soothing and cooling effect 10the face. Five of them thought that theliposome formula was more effectiveat soothing, moisturizing and calmingthe skin aftcr a four-hour period. Ofthe four panelists who tried the formu-lations on sunburnt skin, all perceiveda temporary pain-relieving effect for4-6 hours as opposed 10 the 3-4 hoursfor the control.

Liposomal eye cream (Formulation2). This formulation contains theliposome of LYCD combined with theliposome of retinyl palmitate. It wasused to lest the stability of encapsulat-ed liposomes.

Urban protection cream (Formula-tion 3). This formulation. which con-tains the liposome form of superoxidedismurase. reduces the formation ofmalondialdehyde (MDA) in the pres-ence of UVA light. Superoxide dismu-lase is an enzyme which decomposessuperoxides which can damage skintissue and cause premature agingeffects.

REFERENCES1. Ostro, M., Liposomes, Marcel

Dekker tnc., New York, NY,1983, pp. 1-23.

2. Handyani-Vila, R., B. RondotRibier and G. vauterbergfue.International Journal CosmeticScience J :303(1979).

3. Redziniack. G .• and A. Meybeck.U.S. Patent 4.508.703. 4,621,023P.e. Dior Assignee (1985,1986).

4. Redziniack. G .• A. Meybeck andB. Perrier. IFSCC CongressBarcelona rrepritus J :299 (1986).

5. Siciliano. A.A .• Cosmetics andToiletries 100(5): 43 (1985).

6. Thrwat. R.• and V. Brown. Ency-clopcdia of Emulsion Technology.Basic Theory. Vol. J. P. Becher.editor, pp. 160-162 (1983).

7. Mayhew. E., G. Nikolopoulos.J.J. King and A. Siciliano, Phar-

SURFACTANTS & OmRGENTS

P&G announces bar soap expansion

maceutical Manufacturing2(8): 18 (1985).

8. Perrier. B., and G. Redziniaek,Soap, Perfumery and Cosmetics62(2):57 (1989).

9. Rieger. M.M., Cosmetics and Toi-letries 96(8):35 (1981).

10. Counts. D.E. F, Skrenko, J.

The Procter & Gamble Co. (P&G)plans to expand and modernize the barsoap operation at its Ivorydale plant inSI. Bernard. Ohio.

The project will add 65,000 squarefeet, with construction expected tobegin this month, the company said.Completion is set for mid-I991.

"This project will ensure that wehave a state-of-the-art bar soap opera-tion that is ready to meet business andcompetitive challenges well into oursecond century," according to sitemanager Ken McWhorter.

The Ivorydale site. in use since1886, also produces powdered laundrydetergent, household cleaning prod-ucts, food and industrial chemicals. Itincludes a research and developmentcenter and a major distribution facili-ty. Approximately 2.550 persons workat the complex.

Ivorydale's powdered laundrydetergent operation also is being mod-ernized and expanded. This project.begun in December 1989. is expected10 be completed in mid-I99I.

P&G earlier announced plans tophase out operations at its Pert Ivoryplant on Staten Island. New York. byFebruary 1992.

New LAB plantslated for QuebecPetroquimica Espanola SA (Petresa).a subsidiary of Cepsa of Spain. hasannounced it is forming a 70-30 jointventure with the government-ownedSociete Generate de Financement inCanada 10 construct and operate a75.000 metric ton (M1) per year lin-

McBee and A.G. Wich, J. Soc.Cosmet. Chern. 39(7):235 (1988).

II. Schmitt. K., IFSCC CongressLondon Preprinrs 1:31(1988).

12. Ostro, M.J., Scientific American56:132 (1987).

13. Fendler. J.R. C&E News 62(1):25 (1984).

ear alkylbenzene (LAB) plant in Que-bec. Canada.

A site is being sought in the St.Laurent area, with constructionexpected to Start by the end of 1990with completion in late 1992. TheLAB produced will be aimed at theNorth American market.

The facility will usc fixed-bedalkylation technology, developedjointly by UOP and Cepsa, which thefirms say is less COSIly to build andoffers environmental benefits overconventional processes. Petresa's180,000 MT LAB plant at San Roque.Spain. is the world's largest LABfacility.

The Canadian venture will beCepse's first unit outside Europe.

Plants announced forper borate monohydrateIn response to a global trend towardthe use of sodium perbcrere monohy-drate in detergents, several companieshave announced projects to producethe solid peroxygen bleaching chemi-001.

E.!. du Pont de Nemours & Co.will become the first U.S. producerwhen production begins in January1991 at its Memphis, Tennessee.plant. The company has said part ofthe plant's tetrahydrate capacity willbe used to supply more than 30 mil-lion pounds of monohydrate per year.Monohydrate is often preferred overtetrahydrate because it dissolves fasterand gives better stability for low- orno-phosphate detergent formulas,according to company officials.

INFORM. Vol. 1. no. 10 (October 1990)