AU597333B2 - Dental cream package - Google Patents

Description

CO ir1?~~~~rrTH Op 1A Patent Act 1952 59 3 3 COMPLETE SPECIFICATI ON

(ORIGINAL)

Class Int. Class Application Number 6 qo o6 Lodged Complete Specification Lodged Accepted Published This document contains the amendments made under Section 49 and is correct foiL printing.. i Priority 28 February 1986 Related Art a 4 6 fl 6 4 4 0 os o 4l I 4 446 o04 0 *w 04 94 4 4 04t 4 4 *4t Name of Applicant Address of Applicant COLCATE-PALMOLIVE COMPANY 300 Park avenue, New York New York 10022, United States of America Marie Brett, Harry Hayes F.B. RICE CO., Patent Attorneys, 28A Montague Street, BALMAIN 2041.

Actual Inv ntor/s Address for Service Complete Specification for the invention entitled: DENTAL CREAM PACKAGE The following statement is a full description of this invention including the best method of performing it known to us/KX:i I ~lcnu~ 2 This invention relates to a dental cream packaged in a plastic laminate tube, mechanical dispenser, flexible sachet or the like. In particular it relates to a dental cream in compatible contact with a polyolefin surface of a package such as a plastic laminate dental cream tube, mechanical dispenser or flexible sachet.

Dental creams have been packaged for many years in Sflexible metal tubes such as wax lined lead tubes, unlined aluminum tubes or aluminum tubes having an epoxy resin lacquer coating thereon. In recent years flexible form-retaining laminated plastic tubes have been increasingly used.

i Plastic laminated dental cream tubes typically comprise an inner polyolefin resin layer which is in direct contact with the dental cream and at least one intermediate layer, including an aluminum foil layer which inhibits loss of flavor from the dental cream. Desirably, an intermediate paper layer which provides stiffness to i the tube is also present. The outer layers are typically i 20 of polyolefin resins, one of which may be colored white S, and bears printed indicia with a clear polyolefin laminate overlay to protect the indicia. Additional intermediate S* laminate layers of flexible plastic may also be present.

i Mechanical dental cream dispensers may also have a polyolefin surface in contact with dental uream contained therein. In fact, the polyolefin itself may be the housing of the dispenser. Flexible sachet packets may Salso have a polyolefin surface in contact with dental Screams.

Dental creams typically contain a liquid vehicle of water and humectant, a gelling agent solid vehicle and a water-insoluble dental polishing agent. Dental creams composed of such materials wherein the humectant comprises glycerine and sorbitol and the polishing material is at least in major part an alpha alumina trihydrate have been 77 3 successfully packaged in flexible metal toothpaste containers including aluminum tubes having an internal coating of an epoxy resin lacquer layer. However, it has been observed that when such dental creams are packaged in containers having an interior polyolefin surface such as plastic laminated dental cream tubes, mechanically operated dental cream dispensers or flexible sachets, that syneresis occurs and liquids seperate from solids, rendering the dental cream undesirable, when the pHl of the dental cream is reduced with a wa er-soluble material which provides phosphate ion. In commonly assigned U.S.

patent application for "Packaged Dental Cream" filed November 27, 1985 of Sandra Lee Schelm, syneresis of such a dental cream in contact with polyolefin surface is 15 overcome by including polyolefin glycol of average molecular weight of about 200-1000 in the dental cream.

It is an advantage of this invention that phase separation of a dental cream packaged in contact with a polyolefin material is substantially prevented with a 20 acidifying agent. Other advantages will be apparent from consideration of the following disclosure.

In accordance with certain of its aspects, this invention relates to a dental cream package wherein said dental cream is in direct contact with a polyolefin resin surface, said dental cream comprising at least about by weight of a liquid vehicle comprising water, glycerine and sorbitol, the weight ratio of glycerine to sorbitol 1 being from 0.25:1 to about 3:1, a solid vehicle comprising about 0.05%-10% by weight of gelling agent, about 20-75% be weight of a dentally acceptable water-insoluble polishing material, at least a major portion of which is alpha-alumina trihydrate and benzoic acid to reduce the pll of the dental cream to about 6-8.5.

In dental cream formulations, the liquids and solids are necessarily proportioned to form a creamy mass of -1 ,li 'i

H

*I i j i: 1i i j ,:f i i i i jI i t i i i r 4desired consistency which is extrudible from its package.

The liquids in the present dental cream comprise chiefly water, glycerine and sorbitol. The total liquid vehicle comprises at least about 20% by weight of the formulation. It is preferred to use also a gelling agent in dental creams such as the natural and synthetic gums and gumlike materials, e.g. carrageenans such as Irish moss, gum tragacanth, sodium carboxymethyl cellulose, hydroxyethyl cellulose, polyvinyl pyrrolidone, sodium alginate, guar gum, starch, xanthan and the like, including mixtures thereof. Irish Moss, sodium carboxymethyl cellulose and hydroxyethyl cellulose including mixtures thereof are compatible particularly and are preferred gelling agents. The gum content is usually in an amount about 0.05-10% and preferably about 0.5-5% by weight of the formulation.

Water is generally incorporated into the dental cream in amount of about 10-50% by weight, preferably about 15-35%. Glycerine and sorbitol together generally comprise about 15-50% by weight, preferably about 20-35% of the dental cream, with the weight ratio of glycerine to sorbitol being from about 0.25:1 to about 3:1, typically from about 0.25:1 to about 0.8:1 and preferably from 0.6:1 to about 0.8:1. Amounts of sorbitol as used herein are of 25 sorbitol syrup, as commercially available, that is 70% by weight sorbitol in 30% by weight of water.

Dentally acceptable water-insoluble polishing agent is present in the dental cream in amount of about 20-75% by weight, preferably about 35-60%. At least the major portion, that is, about 50-100% of the polishing material is alpha-alumina trihydrate. The minor portion of the polishing material, if present, typically comprises about 5-20% by weight of the polishing material. Di-calcium, phosphate dihydrate, anhydrous dicalcium phosphate, calcium carbonate, tricaclcium phosphate, calcium I #5 S I I IS IpS~t, 5 pyrophosphate, dimagnesium phosphate trihydrate, magnesium carbonate, calcined alumina, zirconium silicate and insoluble sodium metaphosphate are typical.

Dentally acceptable water-insoluble alpha-alumina toothpaste is typically employed in small particle size, e.g. wherein at least about 85% of the particles are smaller than 20 microns and is preferably hydrated, such as that classified as gibbsite (alpha alumina trihydrate) and normally represented chemically as A1 2 0 3 3I120 or Al(OI0) 3 The average particle size of gibbsite is generally about 6 to 9 microns. However, larger particle size alpha-alumina trihydrate, e.g. wherein 20-70% of the particles exceed 20 microns in size, may also be used. A particularly desirable grade of alpha-alumina trihydrate, 15 available from Alcoa as C-333 is a fine grade of gibbsite having the following size distribution: Microns Percent 94-99 <20 85-93 56-67 5 2 8-40 Other desirable grades of alpha-alumina trihydrate include BACO AF-230 and BACO AF-260, available from British Alcoa Aluminium, SH100 from Rhone Poulenc, and 0S4608 and ON14608 o grades from Martinswer Unless the ptI of the dental cream is adjusted, dental S cream containing a substantial amount of alpha-alumina trihydrate is generally highly alkaline, e.g. about 9-30.5. Accordingly acidic materials are often added to such dental creams in order to reduce the pll typically to about 6 to 8.5. As set forth above, when water-soluble phosphate materials are employed to produce such reduction in alkalinity, syneresis occurs unless a further additive, polyethylene glycol of average molecular weight of about 200-1000, is present. In the present Specification reference to the pH is as measured in a 20% aqueous slurry.

In the present invention it has been found that when the pi! is adjusted to about 6-8.5 with benzoic acid syneresis in the presence of a polyolefin package is prevented. Typically about 0.15-0.5% by weight of benzoic acidis effective to produce a pl of about 6-8.5 with various grades of alpha-alumina trihydrate in dental cream. It is preferred that the p1 of the dental cream be j about 7.5-8.5. Reference to pll herein is to a 20% by i ao weight aqueous slurry of dental cream.

Organic surface-active agents may be used in the dental creaia of the present invention to achieve increased 15 pro-phylactic action, assist in achieving thorough and complete dispersion of the instant compositions throughout the oral cavity, and render the dental creams more cosmetically acceptable. The organic surface-active material may be anionic, nonionic, ampholytic or cationic S 20 in nature, but it is preferred to employ as the S. surface-active agent a detersive material which imparts to the cooposition detersive and foaming properties.

S utablX types of such detergents are water-soluble salts I! of bigher fatty acid monoglyceride monosulphates, such as i 25 the sodium salt of the monosulphated monoglyceride of Shydrogenated coconut oil fatty acids, higher alkyl sulphates, such as sodium lauryl sulphate, alkylaryl sulphonates, such as sodium dodecyl benzene sulphonate, olefinsulphonates, such as sodium olefin sulphonate in which the olefin group contains 12-22 carbonatoms, higher alkyl Sulphoacetates, higher fatty acid ester of 1,2-dihydroxy propane sulphonates, and the substantially saturaed higher aliphatic acyl amides of lower aliphatic amino carboxylic acid compounds such as those having 12-16 carbon atoms in the fatty acid, alkyl or acyl radicals and Ihc~rs, II raei -r rr i i 7 the like. Examples of the last mentioned amides are N-lauroyl sarcosine, and the sodium, potassium, and ethanolamine salts of N-lauroyl, N-myristoyl or N-palmitoyl sarcosine, which should be substantially free from soap or similar higher fatty acid material which tends to substantially reduce the effect of these compounds in compositions of the present invention. The amides are particularly advantageous since they exhibit a prolonged and marked effect in the inhibition of acid formulation in the oral cavity due to carbohydrates .o breakdown in addition to exerting some reduction in the r solubility of tooth enamel in acid solutions. Another desirable material is a long chain fatty acid sodium monoglyceride sulphonate used alone or in combination with ao 15 sodium lauryl sulphate.

SOther particularly suitable surface-active materials include nonionic agents such as condensates of sorbitan mono-sterarate with approximately 20 moles of ethylene oxide, condencates of ethylene oxide with propylene glycol S 20 ("Pluronic" materials) and amphoteric agents such as long chain (alkyl) amino-alkylene alkylated amine derivatives, which are available under the trade-mark "Miranol" such as Miranol C 2 m. Cationic surface-active germicides and antibacterial compounds such as di-isobutyl phenoxy ethoxy ethyl dimethyl benzyl ammonium chloride, benzyl dimethyl stearyl ammonium chloride, benzyl diethyl stearyl ammonium chloride, tertiary amines having one fatty alkyl group (of from 12-18 carbon atoms) and two (poly) oxyethylene groups attached to the nitrogen (typically containing a total of from about 2 to 50 ethanoxy groups per molecule) and salts thereof with acids, and compounds of the structure.

(CH2CII20) H (CII 2CII20)xII R-N-CII2CII2CIIN- (CIICI20 yII 8 where R is a fatty alkyl group containing from about 12 to 18 carbon atoms, and x, y and z total 3 or higher, as well as salts thereof with mineral or organic acids, may also be used. It is preferred to use from about 0.05 to 5% by weight of the foregoing surface-active materials in the dental cream. It is most preferred that the surface-active agent be an anionic material, particularly sodium lauryl sulphate.

The dental cream suitably may also contain a fluorine-containing compound having a beneficial effect on the care and hygiene of the oral cavity, diminution 4 0 o' of enamel solubility in acid and protection of the teeth against decay. Examples thereof include sodium fluoride, o stannous fluoride, potassium fluoride, potassium stannous 15 fluoride (SnF 2 sodium hexa-fluorostannate, stannous S chlorofluoride, sodim fluorozirconate, and sodium monofluorophosphate. These materials which disassociate or release fluorine-containing ions in water, suitably may be present in an effective but non-toxic amount, usually S 20 within the range of about 0.01 to 1% by weight of the water soluble fluorine content thereof.

a The preferred fluorine-containing compound is sodium ,n monoflu-rophosphate typically present in an amount of about 0.076 to 7.6% by weight, preferably 0.76%. A mixture of '"dium monofluorophosphate and sodim fluoride is also desirbale, for instance in a weight ratio of about 2:1 or 1:1 based on fluoride, in amounts preferably providing about 1500-1450 ppm soluble flouride.

Any suitable flavoring or sweetening materials may be employed in formulating a flavor for the composition of the present invention. Examples of suitable flavoring constituents include the flavoring oils, oils of spearmint, peppermint, wintergreen, sassafras, clove, sage, eucalyptus, marjoram, cinnamon, lemon and orange, as well as methyl salicylate. Suitable sweetening agents a^ 9 include sucrose, lactose, maltose, xylitol, sodium 6-methyl-3, 4-dihydro-l, 2, 3-oxathiazine-4-one, sodium cyclamate, perillartine and sodium saccharin. Suitably, flavor and sweetening agents may together comprise from about 0.01 to 5% or more of the compositions of the instant invention.

Various other materials may be incorporated in the dental cream. Examples thereof are coloring or whitening agents or dyestuffs, anti-corrosiveagents, preservatives, silicones, chlorophylic compounds, ammoniated materials St t such as urea, diammonium phosphate and mixtures thereof and other constituents. Whitening agents, such as titanium dioxide, typically in amounts of about 0.5-2%, may be beneficial to the appearance of the dental composition, since upon aging, some discoloration may occur. It is noteworthy that sodium benzoate preservative may assist in reducing syneresis of the dental cream in contact with polyolefin surface, typically when present in amount of about 0.25-0.75% by weight; preferably about o The adjuvants are incorporated in the instant oompositions in amounts which do not substantially adversely affect the properties and characteristics desired and are selected and used in proper amounts depending upon the particular type of composition involved.

I; Antibacterial agents may also be employed in the oral .r compositions of the instant invention in an amount of t about 0.01-5% by weight. Typical antibacterial agents include: 30 1 -(4-chlorobenzyl (2,4-dichlorobenzyl) biguanide; p-chlorophenyl biguanide; 4-chlorobenzyhydryl biguanide; 4-chlorobenzhydrlyluayurea N-3-lauroxypropyl-N -chlorobenzylbiguanide; 1,6-di-chlorophenylbiguenidohexane; 4 10 1,6-bis-(2-ethylhexylbiguanide) hexane; 1- (lauryldimethylamiti.n i un (p-chlorobenzyldi methylammonium) octane dichloride; 5,6-dichloro-2-guanidinobenzimidazole; 1 5 N -p-chlorophenyl-N -laurylbiguanide; 3-bis(2-etheyl-exyl5-methylhexahy-dropyrimidine and their non-toxic acid additon salts.

The package into which the dental cream is incorporated may be any polyolefin laminate dental cream tube. For instance, the tube may be as elementary as is described in U.S. Patent 3,260,410 to Brandt et al, the disclosure of which is incorporated herein by reference.

0 0 o a As described in the example thereof, an aluminum foil base Oo having a thickness of about 0.0013 cm was heated to a 15 temperature of approximately 1770C., and one face of the o"0 heated foil was contacted by an extrudable film of a random copolymei, of ethylene and acrylic acid (acid content 3+0.5% and melt index while the opposite surface thereof had placed thereagainst a film of low density polyethylene.

0 00 oa 'o sing driven rolls a 1i:ainated base was obtained in o which the copolymer layer was about 6 mla and the polyethylene layer was approximately 5 ms in thickness.

The base was then shaped into tubular form and sealed.

After severing the tubular form into tube bodies, the Sf" tubes can be packed with the dental cream of the present invention.

Polyolefin laminate dentifrice tubes containing more intermediate layers may also be successfully used with the 30 dental cream of the present invention without undergoing syneresis. For instance, the multiple layer flexible sheet structure for dental cream tubes descirbed as "Prior Art" in U.S. Patent 4,418,841 to Eckshein may be employed as well as the more crack resistant structures described therein. The disclosure of U.S. Patent 4,418,841 to Y'C -I 44 4 4n 4rr 4 4 i 44 44 2 4 22 11 Eckstein is incorporated herein by reference. In fact, dental creams of the present invention packed in tubes of sheet material identified as Prior Art A and A-i in U.S.

Patent 4,418,841 are very satisfactory and undergo substantially no syneresis. Such tubes A and A-I are comprised of layers as set forth below, in the order of outerniostlayer to innermost layer.

A A-1 1.5 mil LDPE 1.5 ml LDPE mil Pigmented LDPE 2.0 mil Pigmented LDPE 1.6 mil Paper 1.6 mil Paper 0.7 mil LDPE 2.0 mil LDPE 3.3 mil EAA 1.0 mil OPP 15 0.7 mil Foil 1.0 mll EAA 2.0 mil EAA 0.7 mil Foil 1.2 mil LDPE 2.0 mil EAA 13.0 mil Total 1.2 mil LDPE 13.0 mil Total In A and A-i the abbreviations have the following meanings: LDPE low density polyethylene EAA ethylene acrylic acid OPP oriented polypropylene Mechanically operated dispensers, such as the dispenser for, in particular, pasty substances, described in U.S. Patent 4,437,591 to von Schuckmann, the disclosure of which is incorporated herein by reference, may also be used with the practice of the present invention. The housing of such dispensers is commonly composed of a 30 polyolefin resin such as polypropylene. Thus the houising resin is in essence a layer, the inner surface of which is in contact with dental cream. When the dental cream of the present invention is packaged in such a polypropylene mechanical dispenser, it undergoes substantially no syneresis.

4 tt 21 $2 j I I T -12 The advantages of the invention are also present when the dental cream is packed in a flexible sachet having a polyolefin surface, typically of low density or medium density polyethylene.

The following illustrative examples are further illustrative of the nature of the present invention but it is understood that the invention is not limited thereto.

All amounts and proportions are by weight except as otherwise indicated.

EXAMPLE I The following dental creams are prepared to creamy consistencies and packed into tubes of each of laminated structures A and A-l, set forth above: Parts A B i Glycerine 10.000 10.000 Sorbitol 17.000 17.000 Sodium Carboxymethyl cellulose 0.900 0.900 i 20 Sodium Saccharin 0.200 0.200 Tetrasodium pyrophosphate 0.250 0.250 Sodium Monofluorophosphate 0.760 0.760 Sodium Fluoride 0.100 0.100 Benzoic acid 0.250 0.250 Sodium Benzoate 0.500 Deionized water-irradiated 15.646 16.146 Alpha-alumina trihydrate (BACO AF-230) 51.500 51.500 Titanium Dioxide 0.500 0.500 Sodium lauryl sulfate 1.444 1.444 Flavor 0.950 0.950 SpI (20% slurry) 8.2 8.2 After aging for at least 9 weeks at 49 0 C, dental 1 r -1 -Ti I- i 13 ir creams and remain creamy in consistency in laminate tubes of each o' laminate Structures A and A-i. Similarly formulated dental creams with sodium diacid orthophosphate to reduce the pt quckly separate at room temperature and 49 0 C. in both of tubes of Structures A and A-1.

EXAMPLE 2 Dental creams and are incorporated into a mechanical dispenser in accordance with U.S. Patent 4,437,591 composed of polypropylene housing. Dental creams and retain their creamy consistency.

EXAMPLE 3 Similar results to those described above for Examples 1 and 2 are observed when: the relative amounts of glycerine and sorbitol are 6:24 and 18:6; (ii) Sodium fluoride is omitted and its amount replaced by water; (iii) The dental creams are packed in laminated tubes in accordance with U.S. Patent 3,260,410; (iv) The dental creams are packed in crack-resistant laminated tubes in accordance with U.S. Patent 4,418,841; The dental creams are packed in flexible 30 sachets of the following structure from outermost to innermost layer; 12.3 u polyethylene terephthalate 21.3 u white ethyene acrylic acid u foil 3.3 u eOhylene acrylic acid 25.4 u medium density polyethylene; d1 44 444 4 44 44 4 4 44 -14 (Vi BN~C0 A1F-Z30 alpha-alumina trihydrate i~s replacq'd by each of Alcoa C'-333, Rhone Poulenc S S11100 Martinswerk 0S4608 and 0144608 alpha-alumina trihydrat, (vii) 3.000 parts of calcined alumina replace 3.000 parts of alpha-alumina Lribydrate; and (viii) 10 parts of~ insoluble sodium metaphosphate replace 10.000 parts of'alpha-alumina Lrihydrate.

(ix) oodium cyclamate replaces sodium saccharin.

It is understood that the foregoing detailed dc;-ription is given mierely by way of illustration and that variations may be made thergin witbout department from the spirit of the invenztion.

Claims (6)

11. 1. A dental creampackage wherein said dental cream is wh( in direct conti ct with a polyclefin resin package surface, said dental cream comprising at least 20% by

12. weight of a liquid vehicle comprising water, glycerine whc and sorbitol, the weight ratio of glycerine to sorbitol

13. being from 0.25:1 to 3:1, a solid vehicle comprising sal 0.05-10% by weight of gelling agent, 20-75% by weight of has a entally acceptable water-insoluble polishing I

14. material, at least a major portion of which is wh< alpha-alumina trihydrate, and benzoic acid to reduce the w i po] pH of the dental cream to 6-8.5. 2. The dental cream package claimed in Claim 1 wherein sal o >sai the weight ratio of glycerine to sorbitol is from 0.25:1 1 6 o i; 16. to 0.8:1. 3. The dental cream package claimed in Claim 2 wherein a wh sac the weight ratio of glycerine to sorbitol is from 0.6:1 p to 0.8:1. 4. The dental cream package claimed in Claim 1 wherein Dat benzoic acid is present to reduce the pH of the dental cream to 7.5-6.5. The dental cream package claimed in Claim 1 wherein i benzoic acid is present in amount of 0.15-0.5% by weight. 6. The dental cream package claimed in Claim 1 wherein 4 4"P 0.25-0.75% by weight of sodium benzoate is present. 7. The dental cream package claimed in Claim 1 wherein fluorine-containing compound is present in amount cortesponding to 0,01-1% by weight based on watersoluble fluorine contents. 8. The dental cream package claimed in Claim 7 wherein sodium monofluorophosphate is present. 9. The dental cream package claimed in Claim 1 wherein a mixture of sodium monofluorophosphate and sodium fluoride is present in a weight ratio of 2:1 based on fluoride. I it 0 i 43 43 Uj '3 43 4343 [i 41 16 The dental cream package claimed in Claim 1 wherein said dental cream is packed in a plastic laminate tube. 11. The dental cream package claimed in Claim wherein the inner polyolefin resin surface of said plastic laminate tube is polyethylene. 12. The dental cream package claimed in Claim 11 wherein said polyethylene is low density polyethylene. 13. The dental cream package claimed in Claim 1 wherein said dental cream is packaged in a mechanical dispenser having a housing of polyolefin resin. 14. The dental cream package claimed in Claim 13 wherein said polyolefin resin of said housing is polypropylene.

15. The dental cream package _laimed in Claim 1 wherein said dental cream is packaged in a flexible sachet.

16. The dental cream package claimed in Claim wherein the inner polyolefin resin surface of said sachet is low density polyethylene or medium density polyethylene. Dated this 18th day of February 1987. I ;0 0 0 .3 434 COLGATE-PALMOLIVE COMPANY Patent Attorneys for the Applicant F.B. RICE CO. I L