U.S. patent number 3,723,614 [Application Number 05/104,494] was granted by the patent office on 1973-03-27 for maltese-cross scored tablet.
Invention is credited to Theodor Langauer.
United States Patent |
3,723,614 |
Langauer |
March 27, 1973 |
**Please see images for:
( Certificate of Correction ) ** |
MALTESE-CROSS SCORED TABLET
Abstract
A tablet having a breaker-score assuring accurate and easy
breakage into predetermined portions.
Inventors: |
Langauer; Theodor (Muttenz,
Baselland, CH) |
Family
ID: |
22300798 |
Appl.
No.: |
05/104,494 |
Filed: |
January 6, 1971 |
Related U.S. Patent Documents
|
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
777091 |
Nov 19, 1968 |
|
|
|
|
Current U.S.
Class: |
424/467;
D24/103 |
Current CPC
Class: |
A61J
3/10 (20130101); A61K 9/2072 (20130101) |
Current International
Class: |
A61K
9/20 (20060101); A61J 3/10 (20060101); A61k
009/00 (); A61j 003/10 () |
Field of
Search: |
;424/15 ;D16/3 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
352,208 |
|
Sep 1937 |
|
IT |
|
1,200,790 |
|
Sep 1965 |
|
DT |
|
6,972 |
|
Jun 1885 |
|
GB |
|
438,385 |
|
May 1912 |
|
FR |
|
Other References
Encyclopaedia Britannica Vol. 6 pp. 752-755, entry "Cross"
(1957).
|
Primary Examiner: Rose; Shep K.
Parent Case Text
This application is a continuation of Ser. No. 777,091 filed Nov.
19, 1968, now abandoned.
Claims
I claim:
1. A tablet having opposite generally plane surfaces, and a
peripheral edge surface extending between said opposite plane
surfaces and generally perpendicular to said plane surfaces, one of
said plane surfaces having at least two scores in the surface
thereof from the center of the plane surface to a point adjacent
the peripheral edge thereof, the bottom of each score diverging
from a base plane through the bottom of the score at the center of
the said one plane surface and toward the interior of the tablet as
it extends toward the peripheral surface of said tablet and being
spaced from said plane at said point adjacent said peripheral edge
surface a distance of from one to three times the distance of said
base plane below said one plane surface at the center of said
tablet, said tablet having a predetermined dose of medicament
dispersed substantially uniformly throughout.
Description
DETAILED DESCRIPTION
The invention concerns scored tablets which can be broken
accurately and easily into predetermined portions.
Surface scoring of compressed masses, such as tablets, is a common
technique for halving or quartering the compressed shapes.
The tablet is thereby provided with one or with two tapered scores,
which in the case of tablets having a circular horizontal
cross-section, are placed diametrically. Where tablets have a
cross-section which is not circular, the scores are placed
diametrically or parallel to the edges. At the same time they are
placed so that the foot-points forming the base line of the scores,
formed in each case by two faces lying at an acute angle, lie in a
plane which is parallel to the horizontal cross-sectional plane
(base plane). The scores thus penetrate, e.g., in the case of the
biplanar circular tablets, into the tablet everywhere to the same
depth -- except within any existing outer edge bevel: tablets
having a breaker-score or cross score.
The sectioning of scored tablets is designed so that the active
substance contained in each tablet (medicaments, active
pharmacological agents) can be administered fully or to the extent
of half or a quarter, depending on prescription or requirement.
Each amount of active substance separated in this manner from the
tablet, then constitutes in itself a new separate dosage of a
medicament and is thus governed by the same presecriptions
regarding accuracy and permissible limits of dosage, as in the case
of the undivided tablet.
Variations in weight and therefore in content of the active
substances in the separated portions of conventionally scored
tablets having a single score or cross-score, are in many cases
considerably greater than in the case of undivided tablets. The
mass and therefore the active substance content in separated
portions of tablets, having a single or cross-score according to
the invention, are, on the other hand, subject to considerably less
scatter around the theoretically mean value, than the scatter
resulting from tablets provided with a single or cross-score in the
conventional manner. This is shown from measurements which have
been statistically evaluated and which have shown significant
differences in weight variations.
Table
Divisibility of biplanar tablets having cross-scores with
significance test (F-Test) of the variances of the mean mass of
quarters of tablets.
The two variances S.sub.1 .sup.2 (for normally scored tablets) and
S.sub.2 .sup.2 (for tablets having a Maltese-cross score) vary
significantly with respect to each other, when (S.sub.1 .sup.2
S.sub.2 .sup.2) > F.sub.sign, whereby S.sub.1 > S.sub.2,
for a significance-probability of P = 0.05
(according to Geigy documentation Scientific Tables, 6th Edition,
p. 146 ff. and General Methods-theory of Statistics II by J.
Pfanzagel, Berlin 1962, p. 187-190).
Type of Mean S.sub.rel of the Variance Extreme weight-variations of
tablet-quarters in % of the theoretical mean value of the
tablet-quarters score mean value of the weight of tablet- quarters
(4 .times. 40 quarters) in % S.sub.1.sup.2 /S.sub.2.sup.2 Normal
10.1 S.sub.1 .sup.2 = 102.0 up to + 50% and - 57% score (NK) 2.8
Maltese- 6.0 S.sub.2 .sup.2 = 36.0 up to + 18% and - 14% cross
score (MK) according to invention F.sub.sign : upper
significance-limit of F-distribution = 1.69 for (n-l) = 39 S.sub.1
.sup.2 : variance of means weight of tablet-quarters of normally
scored tablets S.sub.2 .sup.2 : variance of mean weight of
tablet-quarters of Maltese-cross scored tablets S.sub.rel :
relative standard variation of the mean value of the
tablet-quarters P : significance probability n : number of tablet
quarters Calculations of S.sub.rel are based on measurements on 4
.times. 10 tablets which were divided up by four people into 40
quarters in each case.
As can be seen from the table, the extreme mass variations given by
the tablet quarters in the case of tablets having normal scores,
are quite appreciably greater than with tablets having the
Maltese-cross score according to the present invention. The
variances S.sub.1 .sup.2 and S.sub.2 .sup.2 differ significantly
from each other. The object of the invention is therefore to score
the tablets in such a way that the mass or the content or dosage of
active substance in the parts separated by breaking off along the
scoring, is considerably nearer to the theoretical mean value, than
in the case of tablets scored in the conventional manner. The
tablet according to the invention, having a breaker-score, is
characterized in that the depth of the acute-angled breaker-score
increases towards the periphery of the tablet.
The invention will now be described more particularly in connection
with the accompanying drawing, in which:
FIG. 1 is a top view of the tablet according to the present
invention;
FIG. 2 is a right side view thereof;
FIG. 3 is a cross-sectional view taken on line 3--3 of FIG. 1;
FIG. 4 is a bottom view thereof; and
FIG. 5 is a top plan view of a modified embodiment of the tablet
disclosed in FIG. 1.
The tablets produced according to the invention are provided either
with a single score (FIG. 5) or with a cross-score (FIG. 1), which
is so arranged that the foot-points forming the base line of the
score, fall below the base plane of the score towards the periphery
of the tablets, the base plane being taken as running through a
point on the base of the score at the center of the tablet, or
through the point of intersection of the crossed scores.
The dipping of the base of the score below the base plane can
either proceed uniformly towards the outer edge of the tablet
(straight line connecting the base points of the score) (FIG. 3),
or it can proceed nonuniformly (curved line connecting the base
points of the score).
In FIGS. 2 and 3, h = depth of score at point of intersection of
the scores, or in the middle of the overall length of a single
score, this height being the distance from the surface of the
tablet to the base-plane.
The wedge-shaped part of the upper punch which projects out beyond
the outer bevelled edge, is advantageously machined at the ends to
be steeply inclined inwards from the outer edge of the bevel (from
the edge of the press tool to about the middle of the bevel), in
order to avoid any damage to the edge of the die by the upper
punch.
Depending on the breaking properties of the tablet material and the
breaking strength (hardness) of the tablets, the amount of dip of
the bottom edge of the score below the base plane at a point on the
outer edge of the tablet, where the line of slope of the score is
extended to, is
a. in the case of biplanar tablets, as much as tablet material,
tablet strength and pressing technique require or permit,
preferably, however, it is 11/2 to 3 times the score depth h at the
center point of the tablet,
b. in the case of tablets, the curved outer surfaces of which are
scored, as much as tablet material, tablet strength and pressing
technique for press tools require or allow, depending on radius of
curvature, preferably it is 1 to 3 times the score depth h.
The score has an opening angle formed by the two faces of the score
meeting at the base of the score, of preferably 50.degree. to
55.degree., and this is maintained constant independently of the
score depth (FIG. 2).
* * * * *