Note: Descriptions are shown in the official language in which they were submitted.
~ .. ` ~ @~ 13~7~28
: ;
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 ccmpatible 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 flexible metal
tubes such as wax lined lead tubes, unlined aluminum tubes or aluminum
tubes having an epoxy resin lacquer coa~ing tnereon. In recent years,
flexible form-retaining lamina~ed plastic tubes have been increasingly used.
Plastic laminated dental cream tu~es typically comprise in inner
polyolein resin layer which is in direct contact with th~ dental cream and at
~east one intenmediate layer, including an aluminum foil layer which inhibits
loss of flavor from the dental cream. Desirably, an intermediate paper layer
which provides stiffness to the tube is also present. m e outer layers are
typically of polyolefin resins, one of which may be colored white and bear
- printed indicia with a clear polyolefin laminate overlay to protect the
indicia. Additional intermediate lamunate layers of flexible plastic may also
be present. b
Mechanical dental crsam dispensers may also hav~ a polyolein
li surface in contact with dental cream contained ~herein. In fact, ~he
polyolefin itself may be the housing of the dispenser. Flexible sachet
packets may also have a polyolefin surfacein contact with dental crean.
DentaI creams typically con~ain a liquid vehicle of water and
humectant, a gelling agent solid vehicle and a water-insoluble dental
polishing agent. A surface active is also generally included. Dental creams
composed of such materials wherein the humectant ccmprises glycerine and
r sorbitol and the polishing material is an alkaline earth metal salt such as
- 2 -
'. , , ~
1~27528
~ 62301-1513
~ dicalcium phosphate have been successfully packaged in flexible
- metal toothpaste containers includiny aluminum tubes which are
unlined or which hava an internal coating of an epoxy resin
` lacquer layer. However, it is observed that when such den~al
-~ creams are differently packaged in containers having an
lnterior polyolefin surface such as plastic laminated dental
cream tubes, mechanically operated dental cream dispensers or
flexible sache~s, tha~ syneresis becomes a problem and liquids
~` separate from sollds, rendering the dental cream undesirable.
, ,
In earlier commonly assigned patent disclosures
additives to prevent dental cream syneresis upon contact with a
polyolefin surface have been disclosed for dental creams
containing an alkaline earth metal phosphate or alpha-alumina
trihydrate polishing agent. These disclosures are:
Canadian Patent 1,282,341, issued 2 April 1991,
whereln the anti-syneresis additive for an alkaline
earth phosphate dental cream is a polyethylene
01y~ol;
-`~ Canadian Patent 1,282,708, issu~d 9 April 1991,
wherein the anti-syneresis additive for a dental
cream in which the polishing agent is mainly an
alkaline earth metal phosphate is propylena ylycol;
Canadian Patent 1,294,556, issued 21 January 1992,
wherein the anti-syneresls additive for an alpha-
alumina trihydrate dental cream is a vegetable oil;
and
Canadian Patent 1,294,557, issued 21 January 1992,
wherein the anti-syneres~s additive for an alkaline
earth metal phosphate dental cream is a vegetable
oil.
@~ `
:`~
` ~
~2752~ 62301-1~13
i i~
~ In each of the foregoing patent disclosures
::
~ condensates of ethylene oxlde with propylene glycol, that is
~ ~,
"Pluronic*" materials, are generally disclosed as a type of
surface-active material which may be present in the several
;.,i,;
dental creams containing the described particular anti~
-~ syneresis additives.
~: Japanese Public Disclosure No. 75410/85 to Ebine et
al (Lion Corpora~ion) describes a dentifrice in which glycerine
~,
~:: is the sole humectant or mixed with another humectant, such as
10 sorbitol, but which glycerine is, in any event, present in
:-.:
: amount greater than 20% by weight of the dentifrice, since
; .
~ lesser amounk~ would re~ult in undesirable evaporation of water
. .,
~` when the dentifrice is packed in a con~ainer having a plas~ic
~I container body, at least the barrel portion of which has a
:l~ water permeability of at least 5g~m2.day.50u. The high
. .
glycerine dentifrice is formula~ecl to avoid evaporation and
~; weight loss in this particular type of container. The
l disclosure includes a general indication that polymer of
:~. e~hylene oxide and propylene oxide may be employed as surface-
~,;2 20 active agent.
U.S. Patent 4,556~553 ~o Suganuma et al (Lion
i Corporation) discloses dentifrices containing an aluminum oxide
abrasive in a container having an
,
s
,' .
*Trade-mark 4
,@æ
2 ~ ~ 2 8 ~ ¦
. .
oxygen permeability of at least 3cc/m2.dayOatm wherein antiseptic properties
are improved by the presence of polyhydric alcohol, including mixture of
sorbitol and glycerine. There is a general disclosure that condensates vf
ethylene oxide with propylene oxide may be used as a sur~ace-active agent in
the aluminum oxide dentifrices. Some dentifrice samples are described for
ccmparative purposes which contain dicalcium phosphate with sodium lauryl
sulfate as the sole surface active ag~nt.
Japanese Public Disclosure 86526~78 to Naganuma et al ~Lion
Den~ifrice Campany) diclo~es that liquid-solid seEkaration in toothpa~te
containing an anionic surfactant and a polyo~yethylene bloek copolymer t~pe
surfactant (that is, a "Pluronic" sur~actant) can be ~ver~come by employin3 a
binder or gelling agent of at least one of hydroxyethyl cellulose and/or
xanthan gum rather than carrageenan, gum tragacanth, sodium carbox~methyl
cellulose, poly~sodium acrylate) or guar gum. The toothpastes described
contain a humectant such as glycerin, sorbitol, propylene glycol or
polyethylene glycol. The only mixtures of humectants described in specific
formulations including those which evince separation when a gelling agent
other than hydroxyethyl cellulose or xanthan is employed, contain glycerine
and propylene glycol.
U.S. Pa~ent 4,353~890 to Scott (Colgate-Palmolive C4mpany) di~closes
tcothpastes containing carrageenan gelling agent which is stabilized by
microwave radiation to maintain viscosity. A dicalcium phosphate toothpaste
containing such stabilized carrageenan with a mixed humectant of 4.5% by
weight of glycerol and 17.5% by weight of sorbitol is exemplified and
indicated to be subjected to storage tests, including when packaged in
containers having body portions of polyethylene. m e detergent or
surface-active agent employed in the exemplified toothpaste is sodium lauryl
sulfate m e patent includes a
~ 132'1~2~ ~ ~
general disclosure~"Pluronics(R~" as detergents.
It is an advantage oE this invention that phase separation of a
dental cream packaged in contact with a polyolefin material which would
undergo phase separation but for the pxesence of an additiva which overcomes
syneresis, is substan~ially prevented. Other advantages will be apparent from
consideration of the following disclosurea
In accor~ance with certain of i~s aspects, this invention relates to
a packaged dental cream wherein said dental cream is in direct contact with a
low or medium density polyethylene or polypropylene surfacé, wherein syneresis
occurs in said dental cream due to said direct contact when said dental cream
consists essentially of as ingredients about 20-75% by wei ~ t of a liguid
~icle consisting essentially of about 10-50% by weigh~ of water, about
5Ø15~ by weight of glycerine and sorbitol, th~ amcunt of glycerine and
sorbitol together being about 15-50% by weight, the weight ratio oE glycerine
to sorbitol being ~rom about 0.25:1 to about 1:1, about 0.05-10% by weight of
a dental cream gelling agent selected ~Erom the group consisting of Irish ~oss,
gum tragacanth, sodium carboxymethyl cellulose, hydroxyethyl cellulose,
. p~lyvinyl pyrrolidone, sodium alginate, guar gum, star~h, xanthan ~nd iota-
carrageenan, and about 20-75~ by weight of a dentally acceptable water-
insoluble calcium or magnesium alkaline earth metal salt polishing ag~nt; said
dental cream consisting essentially of said ingredients and as the s~le
additive to prevent syn~resis in said dental cream upon said direct contact,
about 0.1-5% by weight of a nonionic polyoxyethylene-pDlyoxypropylene block
copolymer.
. In dental cream fonmulations, the liquids and solids are necessarily
proportioned to form a creamy mass of desired consistency which is extrudible
frcm its pa k ge. The liquids in the present dental crear co~prise chiefly
,,
. ~ ~ ~3%7~8 ~
,
water, glycerine and sorbitol. ~he total liquid vehicle ~mounts to about
20-75% by weight of the formulation. A gelling agent in the dental creams
is a natural or synthetic gum or gumlike material, particularly, eOg. Irish
Moss (carrageenan), gum tragacanth, sodium carbox~methylcellulose,
hydroxyethyl cellulose, polyvinyl pyrrolidone, sodium alginate, guar gum,
starch, xanthan or iota~carrageenan, including ~ixtures ~hereof. Irish Moss,
sodium carboxymethyl cellulo6e, and iota-carrageenan, including mixtures
thereof are compatible particularly and are preferred gelling agentsn ~he gum
content is in a amount of abou~ 0~05-10~ and preferably abou~ 0.5-5% by weight
of the formulation.
Water i~ incorporated into the dental cream in ~m~unt of about
~0-50% ~y weight, preferably about 15-35%. Glycerine and sorbitol together
generally comprise about 15-50~ by weigh~, preferably about 2U-35~ of the
dental cream, with the amount of glycerin~ being about 5.0-15% by weight and
the weight ratio of glycerine to sor~itol being from about 0.25:1 to about
1:1/ typically frcm about 0.25:1 to about Oo~ l and preferably from about
0.25:1 to about 0.6:1. It is preferred to use about 6-10% by weight of
glycerine and about 17-24% by weight of sorbitol. Amounts of sorbitol as used
herein are of sorbitol syrup, as ccmmercially available, that is 70% by weight
sorbitol in 30% by weight of water.
Dentally acceptable water-insoluble alkaline earth metal salt
polishing agent is present in the dental cream in amLunt of bout 20-75% by
weight, preferably about 35-60%. Typical salts include dicalcium phosphate
dihydrate, anhydrous dicalcium phosphate, calcium carbonate, tricalcium
phosphate, calcium pyrophosphate, dimagnesium phosphate trihydrate and
magnesium carbonate including mixtures thereof. Most preferably, calcium
salt, particu rly dicalcium phosphate dihydrate or mixture of dicalcium
132752g ~ ~
phosphate dihydrate and anhydrous dicalcium phosphate, is present.
In addition to the alkaline earth metal salt polishing agent,
additional polishing agent such as hydrated alu~ina and calcined alumina may
be present, for instance in a weight ratio of alkaline earth metal salt to
alumina material of about 2.5:1 to about 4~ he total a~ount of polishing
material in the dental cream beiny ~bout 25-75% by weight,
The single material employed in accordance with the present
invention to prevent syneresis when the dental crean is in direct contact with
a low or mediu~ density polyethylene or polypropylen~ i5 a nDnionic
polyoxyethylene-polyoxpropylene block copolymer. Ihe block copolymer is also
effective in the dental cream as a surace-active agent. i~t is present in
~ unt of about 0~1-5% by weight, pre~erably about 0.5-3%.
The nonionic surface-active agent employed in the instant invention
is a block copolymer containing polyoxyethylene and polyoxpropylene. Such
block copolymers are available from Wyandotte Chenicals Corporation under the
trademark "Pluronic". They may be lig~id, paste or solid and are ~enerally
chemically defined in terms of the moleculr weîght of the polyoxypropylene
hydrophobic moiety and the percent by weight of the polyoxyethylene
hydrophilic moiety. The following block copolymers are available from
~andotte:
- 8 -
~ 1327~2~
Pluronic Physical Mol. Wt.
Number Character Hydrophil Hydrophobe
I,121 Liquid 10 4000
L101 Liquid 10 3250
L 81 Liquid 10 2250
L 61 Liquid 10 1750
L 31 Liquid 10 350
L122 Liquid 20 4000
L 92 Liquid 20 2750,L 72 Liquid 20 2050
L 52 Liquid 20 1750
L 42 Liquid 20 1200
P 123 Paste 30 4000
P 103 Paste 30 3250 ,
L 63 Liquid 30 1750 -~
~ 43 Liquid 30 1200
P~104 Paste 40 ~3250
P ~4 Paste 40 2750
P 84 Paste 40 2250
P 64 Liquid 40 1750
P 44 Liquid 40 1200
P 105 Paste 50 3250
P 85 Paste 50 2250
P 75 Paste 50 2050
P 65 Paste 50 1750
P 35 Liguid 50 950
F 127 Solid 7~ 4000
F 87 Solid 7~ 2250
P 77 Solid 70 2050 .
F 108 Solid ~ 3250
F 98 Solid 80 2750
F 88 Solid ~ 2250
F 68 Solid 80 1750
F 38 Solid 80 950
~ ~ ~327~2~ ~
.
Ihe preferred nonionic block copolymers are solid ~or flake) materials and the
most preferred are Pluronic F-108 (80% polyo~yethylene: 3250 molecular weight
polyoxypropylene) and F-87 (70~ Eolyoxyethylene 2250 molecular weight
polyoxypropylene), F-127 ~70~ polyoxyethylene~ 4000 molecular weight poly-
oxypropylene) and L-72 ~20% polyoxyethylene: 2050 molecular weight
polyoxypropylene).
Since the nonionic blook copolymer anti-syneresis agent does not
provide substantial foam to the dental cream, an ~nionic surface-active agent
may also be provided for its foaming ~haracter and in order to enhance
detergency. m e surface-active agents may achieve increased prophylactic
action, assist in achieving thorough and complete dispérsign of the instant
itions throughout the oral cavity and render the dental creams more
cosmetically acceptable. Suitable anionic surface-~ctive materials are
water-soluble salts of higher fatty acid moncglyceride monosulfates, such as
the sodium salt of the monosulfa~ed monoglyceride of hydrogenated coconut oil
fatty acids, higher alkyl sulfates, such as sodium lauryl sulfate, alkylaryl
sulfonates, such as sodium dodecyl benzene sulfonate, olefin sulfonates, such
as sodium olefin sulfonate in which the olefin group contains 12-22 arbon
atams, higher alkyl sulfoacetates, higher fatty acid ester of 1,2-dihydroxy
propane sulfonates, and the substantially saturated higher aliphatic acyl
amides of lower aliphatic amino carboxylic acid compounds such as tho6e
havin~ 12 to 16 carbon atcms in the fatty acid, alkyl or acyl radicals and 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 carbohydrate
breakdown in addition to exerting scme reduction in the solubility of tooth
enamel in acid solutions. Another desirable material is a long chain ~atty
acid sodium monoglyceride sulfonate used alone or in combination with sodium
-10-
327~28
.. . .
lauryl sulfate. It is preferr~d to use about 002-5% by weight of total
surface- active agent typically about 1~3%r when anionic surface-active ~gent
is present.
The dental cream suitably may also contain a fluorine-containing
compourd having a beneficial effect on the care and hygiene of the oral
cavity, e.g., diminution of enamel solubility in acid and protection of the
teeth against decay. Ekamples thereDf include sodium fluoride, stanou$
fluoride, potassium fluoride, potassium stanno~s fluoride tSnF2.XF), sodium
hexafluorostannate, stannous chlorofluoride, scdiu~ fluorozirconate and sodis~n
monofluo wphosphate. These materials which disas~ociate or release fluorine-
containing ions in water, suitably may ke present in c~ e~fective but
~;~on-toxic amount, usually within the range of about 0.01 t~ 1% by weiyht of
e water-soluble fluorine content thereof.
The preferr~d fluorine-containing compoun~ is sodium m~nofluoro~
phosphate, typically present in an ar~ount of about 0.076 to 7.6% by weight,
preferably 0.76~. A mixture of sodium nofluorophosphate and sodiun fluoride
is also desirable, for instance in a weight ratio of about 2;1 based on
fluoride.
Any suitable flavoring or sweetening materials may be e~ployed in
fonmulating a flavor for the oomposition of the present invention. E~a~ples
of suitable flavoring constituents inclu~e the flavoring oils, e.g., oils of
spea~mint, peppernint, wintergreen, sassafras, clove, sage, eucaIyptus,
cinnamon, lemon an~ orange, as well as ~eth~l salicylate. Suitable sweetenin~
agents inclu~e sucrose, lactose, maltose, xylitol, scdium 6~methyl-3,
4-dihy~ro-1,2,3-o~athiazine-4-one, scdium cyclamate, perillartine and scdium
saccharin. Suitably, flavor an~ sweetening agents may together co~prise from
about O.Ol to 54 or more of the ~ompositions of the instant invention.
Various other ~aterials may be incorporated in the dental creamr
Ekamples thereof are coloring or whitening agents or dyestuf~s, preservatives
such as scdium benzoate, anti-corrosive agents, silioones, chlorophylic
compoun~s, ammoniate~ materials such as urea, diammonium phosphate ard
muxtures thereofand other constitutents. Whitening agents, such as titaniu~
~ 2 7 ~ 2 8
dioxide, typically in amounts of about 0~5-2%, may be beneficial to the
appearance of the dental composition, since upon aging, sc~e discoloration may
occur.
Ihe adjuvants are incorporated in the instant ccmpositions in
amounts which do not substantially adversely afect the proper~ies and
characteristics desired and are selec~ed and used in proper a~ounts depending
UpGn the particular type of composition involved.
Antibacterial agents may also be employed in the oral compositions
of the instant invention in an amount of about 0.01-5% by weight. Typical
antibacterial agents include:
Nl (4~chlorobenzyl3-N5-(2,4-dichlorob~nzyl) biguanide;
p-chlorophenyl biguanide;
-4-chlorobenzhydryl biguanide;
4-chlorobenzhydrylguanylurea;
N-3-lauroxypropyl-N5-chlorobenzylbiguanide;
1,6-dichlorophenylbiguanidohexane;
1,6-bis-(2-ethylhexylbiguanido) hexane;
l~(lauryldimethylammonium)-8-~p-chlorobenzyldimethyl-ammonium3
octane dichloride,
5,6-dichloro-2-guanidinobenzimidazole;
N -p-chlorophenyl-N -laurylbiguanide;
5-amino~1,3-bis(2-ethylhexyl) 5-methylhexahydropyrimidine and
their non-toxic acid addition salts.
Ihere may be employed also various calcium and magnesium ion
suppression agents for adjustment of physical properties of the comeositions.
Suitable agents are the water-soluble inorganic polyphosphate salts, such as
tetrasodium pyrophosphate or disodium diacid pyrophosphate, with the partially
neutralized or acid polyphosphate preferr~d. Other suitable agents are the
alkali metal, preferably sodium, 5alts of oitric acid. In general, such
ccmpounds will be a minor amount or proportion of tha ~onmulation. Ihe
precise amount will vary depending upon the specific formulation, such as ~he
- 12 -
~ 3~7~28
62301-1513
physical characteristics of the dental cream, but will usually
be from about 0.1% to about 3% by weight.
The dental creams should have a pH practicable for
use. A pH range of 5 to 10 is particularly desirable. The
reference to ~he pH ls meant to be the pH determination
directly on the dental cream~ If desired, materials such as
cltric acid may be added to adjust to the pH to say 6 to 7.
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 descrihed in
U.S. Patent 3,260,410 to Brandt et al. As described in the
example ~hereof, an aluminum foil base having a thiekness of
about 0.0013 cm was heated to a temperature of approximately
177C, and one face of the heated foi.l was contacted by an
extrudable film o~ a random copolymer of ethylene and acrylic
acid (acid contenk 3~0.5% and melt index 8'1), while the
opposite surface thereof and replacecl thereagainst a film o~
low density polyethylene. Using driven rolls, a laminated base
was obtained in which khe copolymer layer was about 6 mils and
the polyethylene layer was approximately 5 mils in thickness.
The base was then shaped into tubular form and sealed.
After severing the tubular form into tube bodies, the
tubes can be packed with the dental cream of the present
invention without the dental cream undergoing syneresis.
Polyolefin laminate dentifrice tubes containing more
intermediate layers may also be successfully used with the
dental cream of the present invention without undergoing
syneresis. For instance, the multiple layer flexible sheet
structure for dental cream tubes described as '-Prior Art" in
U.S. Patent 4,418,841 to Eckstein may be employed as well as
~he more crack resistant structures described therein. In
13
~ 327~2~
62301-1513
fact, dental creams of the present invention packed in tubes oi
sheet material identified as Prior Art A and A-l in U.S. Patent
4,418,841 are very satisfactory and undergo substantially no
syneresis. Such tubes A and A-l are comprised of layers as set
forth below, in the order of outermost layer to inner most
layer.
A A-l
1.5 mil LDPE 1.5 mil LDPE
2.0 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 mll EAA 1.0 mil OPP
0.7 mil Foil 1.0 mil 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-l the abbreviations have the follo~ing
meanings,
LDPE low density polyethylene
EAA ethylene acrylic acid
OPP oriented polypropylene
Medium density polyethylene may replace low density
polyethylene. In a dental cream sachet package medium density
polyethylene i~ preferred.
Mechanlcally operated dispensers, such as the
dispenser for, in particular, pasty substances, described in
U.S. Patent 4,437,591 to von Schuckmann, may also be used with
the practice of the present invention. The housing of such
dispensers is commonly composed of a polyolefin resin such as
polypropylene.
14
"
132~28
m us the housing resin is in essence a layer, the inner surface of ~hich is in
contact with dental cream. When the ~ental cre~ of the present inYention i5
packaged in such a polypropylene mechanical dispenser7 it un~ergoes
substantially no syneresis.
m e following properties are typical of low and m~dium density
polyethylene:
Low Dknsit~ Mbdium Density
PDl~ethylen PDlyethylene
Clarity TransparPnt Tran~parent
to ~o
Translucent Translucent
Yield 30/000 29,500 Sq. in/lb./~.001-in
(1,085,0001/065~000 sq. om/Xg./0.~01-cm)
,~
~, .
Specific 0.910-0.925 0.926-
g~vity 0~940
Tensile strength 1,000- 3,5002,000- 5,000 lb./s~.in.
ASTM D-882
(6,900-24i15013,800-34,500 kPa.)
Elongation 225 - 225 -
~per cent) 600 500
ASTM D~882
Impact Strength 7-11 4-6
(kg-cm)
Tear strength 100- 40050-300 gm~0.001 in. Elmen~orf
ASTM D~1922 (250-1,000 125-750 gm/0.001 cm. Elmendorf)
,,
Heat seal range 250-350 260-310 F
(120-175 125-155 &)
WVTR 1.2 0~5-1.0 gm/24hr/103sq.in.@100OF
90 per cent RH (7.74 3.23-6.4 ~ 24hr~100sq~cm.@37C)
~STM E-96
.
- 15 -
,~ ., ,
,
~ ~ ~3~7~
Low Density Mdium D2nsity
lyethylene Polyethylene_
. .... . .,, j . . _ _ . _ . _
Gas transmission 02-ASTM D-1434 250-840 165-335 cc/O.OOl-in./lOOsq.in./
24 hr.@ ATM 73F~O~ RH
(150-515 100-205 cc/O.OOlcm/lOOs~.om./
24 hr.@AIM22~7 rC~0%RH)
495-5,000 500 840 cc/O.OOl-in/lOOsq.in./
24 hr.Q AlM 73+0~ RH
Gas transmission C02-ASTM D-1434 ~300-3,050 305-515 cc/O.OOl-cm/lOOsq.cm/
~4hr~@ATM22.7 ~C~0%gH)
, , , _ _ ,, ,,, .,, . ,, , , ,,, ,, ~
Resistance to Varies Gbod
grease an~ oils
, . . . .
Maximum Use 150 180-220 F
Temperature (C) (65s5 82-105 &
~inimum Use -60 ~60 ~ ~F
:T~mperature (C) t-51 -51 j &
`:
Dimension change None None
at high RH (per cent)
Machine performance Fair Fair
_ _ . _ _ . . . .
Printability Gbcd if treat~d Gvcd if treated
.
Heat shrinkable Some Some
types types
_ _ _ _
Typical of polypropylene grades whi~h may be employed partisNlarly
as dispenser housing for the dental cream are those 5uppli~d by 5hell Shemical
Ccmpany as Polypropylene DP 5~03 an~ PDlypropylene DP 5A03S. lhese controlled
rheology products cambine the processibility of 12 melt flow gr3~es with
higher practical impact s~rength (as m~asured b~ fallin~ weight testing).
- 16 -
;: ~ ~ ~327~28 ~ i
., .
They were designed for fast processing in multicavity molds-
Polypropylene grades DP 5A03 and DP 5A03S have the following typical
properties: .
.
Traditional ASTM
Units SI Units l`est
Melt flow 12 g/10 min 12 g/10 min D 1238
Density at 23& 0.905 g/cc 0.905 g/cc D 1505
Tensile yield strength, 2
at 5.0 om/min 5000 psi 34 MPa D 638
Yield elongation, 2
at 5.0 cm~min 9% 9% D 638
1% Secant ~odulus, 2
at 0.5 om/min 190,000 psi 1300 MPa D 638
Flexural ~cdUlUs9
at 0.13 cm/min, 5 om span 200,000 psi 1375 MP~ D 790A2
Notched Ixod impact ~ 2
~ strength, ak 70F/230C 0.5 ft-lb/in 26 J/m j D 256?
: ' at 0 F/-18 C 0O3 ft-lb/in 15 J/m D 256 .
hardness, Rockwell R92 R92 ~ 785
~eiat deflection temp.,
at 66 psi/455 kPA 220F 104& D 648
Vicat softenin~ temp. 3~5F 152C D 1525
2C~ndition 230/2.16
ASTM Type I specimen, 0032 cm thick (injection lded)
The advantages of the inven~ion are also-present when the dental
cream is packed in a flexible sachet h~ving an pol~olefin surface, typically
of low density or medium density polyethylene.
The ~ollowing illustrative examples are further illustrative of ~he
nature of ~he present invention but it is understood that the invention is not
limited thereto. All amounts and proportions are by weight except as
otherwise indicated.
EXAMPr.~_l
Ihe following dental creams are prepared to creamy oonsistencies and
packed into tubes of each of lamunated structures A and A-1, set forth above.
. -,..
~;: ~ ~ ~ 3C~2~ ~
Parts B
Glycerine (99.3%~ 10.00 10.00
Sorbitol (70%) 17 7 00 17.00
Sodium Carbo~ymethylcellulose 0.95 0.95
Sodium Saccharin 0.20 . 0.20
Tetrasodium Pyrophosphate0.25 0.25
Sodium Monofluorophosphate Or76 0~76
Dicalcium Phosphate Dihydrate 48.76 48.76
Sodium Lau~yl Sulfate 1.10 ~ 10
avor 0.89 0.8,9
Pluronic F-108 0~50
~ater Q.S.to Q,S. to
100. 00 1O0D 00
Dental cream B begins to undergo syneresis and phase separation
after aging for 8-10 days at room temperature. Dental cream A remains stable
against such phase separation when aged at room temperature for periods
exceeding one year.
EXAMPLE 2
Dental creams (A) and [B) are incorporated into a mechanical
dispenser in accordance with U.S. Patent 4,437,591 c~mposed of polypropylene
housing. Dental cream (1) retains its creamy consistency while dentifrice ~2)
separates into liquid and solid phases.
Similar results to those described in the above Examples are observed when:
(i) Each of Pluronic F-127 and F-87 replaoe Pluronio F-108;
(ii) Pluronic L-72 replaces Pluronic F~
(111~ Pluronic P-84 replaces Pluronic F-108;
(iv) the ccmparative a~ounts of glyoerine and sorbitol (70%)
are: 5:20 and 12:15;
~v) Eac~ of Irish Moss and iota-carrageenan replaoe
sodium carboxymethyl cellulose; ~ .
- 18 ~
. ...........
132752~
(vi) The dental creams are packed in lamunated tubes in
accordance with U.S. Paten~ 3,260,410;
(vii~ The dental cre~ns are packed in crack-resistant
lamunated tubes in accordance with U.S. Patent
4,418,841;
(viii) lhe dental creams are packed in flexible sachets of
the following structure frem outermo6t to innermost
layer:
12.2 ~ polyothylene terephthalate
21.3 ~ white ethylene acrylio acid
9.9 ~ foil "
3,3 ~ ethylene acrylic acid
25,4 ~ medium density polyethylene; and
(ix) Mixture of 0.3 parts o~ sc~ium carboxymethyl-
cellulose and 0.6 parts of. iota-carrageenan replace
of sodium carboxymethyl cellulosP as the sole
gelling material.
. It is understc~d that the foregoing detailed dPscription is given
merely by way of illustration and that v~riations may be made ~herein without
departing from the spirit o the invsntion.
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