Cake of soap

A cake of soap (10) provided with a cavity (12) for receiving a remnant of soap, the cavity (12) extends into the interior region of the cake of soap (10).

This invention relates to a cake of soap. 
More specifically the invention relates to a cake of soap which is adapted 
to receive a remnant of a used cake of soap. 
A cake of soap is usually used until it reaches a stage where is becomes 
difficult to hold and thereafter the user will more often than not simply 
throw the remaining piece of soap away. Typically this discarded remnant 
of soap is in the region of 5 to 15 per cent of the original piece of 
soap. When one calculates the amount of soap discarded by a single user in 
a year the amount wasted in terms of both cost and material can be 
significant. Also the impact of the wasted soap on the environment and 
drainage systems is another cause for concern. 
To overcome this wastage it has been common practice for the user to simply 
mount the soap remnant on top of a new cake of soap so that after some use 
the two pieces of soap are moulded to become one. A problem with this 
practice has been the difficulty of getting the soap remnant to adhere to 
the new cake. Another disadvantage is that such a practice usually 
produces an unattractive and untidy result. 
To overcome these problems, a number of inventions have been proposed, the 
majority of which involve the production of a cake of soap provided on one 
of its major surfaces with a recess shaped to receive a soap remnant. 
However a problem of getting the remnant soap to adhere readily to the new 
cake of soap remained a problem. 
To obviate this problem there have been proposals to provide the recess 
with means to assist the retention of the soap remnant onto the new soap. 
One example provided for a plurality of shallow dimples on the recess to 
act as "suction cups" to hold the soap remnant in place. Another example 
provided raised notches on the recess to "spear" the soap remnant in 
position. 
However the proposals somewhat complicates the manufacturing process of the 
new soap cake which could lead to an increase in costs eventually passed 
onto the consumer. 
The present invention will seek to overcome or at least reduce the above 
identified problems or to provide the public with an alternative choice, 
by providing a cake of soap with means to receive and retain a used 
remnant of soap. 
Thus in one form the invention resides in a cake of soap provided with a 
cavity which is adapted to receive a remnant of soap, said cavity 
extending into the interior region of said cake of soap wherein an opening 
to said cavity is provided on one side face of said cake of soap, said 
cavity having a pair of faces which are in opposed relation between which 
said remnant of soap is receivable. 
It is preferable that the cavity be located along the longitudinal axis of 
the cake of soap. It is also preferable that the cavity be offset from the 
centre of the cake of soap. 
The spacing between the opposed faces of the cavity is preferably less than 
the distance which the cavity extends inwardly from the opening. 
Preferably the opposed faces each extend transversely of the inward extent 
of the cavity and the spacing between the faces is less than the 
transverse extent of the faces. 
Preferably the cavity is elongated and the opening opens into the 
longitudinal extent of the cavity. 
Preferably the cavity is elongated and the opening opens into the 
transverse extent of the cavity. 
In one arrangement an opening to the cavity is provided with the opening 
being located at one end face of the cake of soap. The cavity may be in 
the form of a pocket. In another arrangement two openings to the cavity 
may be provided each being located at opposing end faces of the cake of 
soap. 
The off centre position ensures that when the soap remnant is inserted into 
the cavity and the new cake of soap used, the soap remnant will be totally 
or at least partly used as well. The size of the cavity should be such 
that the soap remnant is able to be inserted within the cavity so that a 
portion of the soap remnant protrudes therefrom. 
The cavity is preferably located a sufficient distance away from the edges 
of the cake of soap so that the surrounding walls of the cavity are of 
sufficient strength so that the cake of soap can be handled without 
damage. 
Preferably the cavity is dimensioned to receive a remnant of soap whilst it 
is still of a reasonable size and before it becomes too difficult to 
handle. Preferably the cavity is dimensioned to receive a remnant of soap 
which is about 5% to 15% of its original size. 
It is also preferable that the cake of soap or soap remnant or both be 
moistened prior to insertion of the soap remnant into the cavity. 
Preferably when the soap remnant is inserted within the cavity a portion 
of the soap remnant protrudes. To lock the soap remnant within the cavity, 
force is applied to the protruding portion thereby forcing the soap 
remnant within the cavity and causing it to deform. This deformation 
preferably fills the mouth portion of the cavity thereby forming a plug 
which at least partly seals the opening.

As seen in the drawings the embodiment is directed to a cake of soap 10 
which in this particular embodiment is of the typical tablet shape. It 
should be appreciated that the shape of the soap can be of any desired 
configuration. 
Located off centre within the cake of soap 10 is a cavity 12 in the form of 
a pocket which extends along the longitudinal axis of the cake of soap 10 
and is preferably of a rectangular or oblong configuration to correspond 
generally to the shape of the used soap remnant. The cavity 12 extends 
more than half way through the longitudinal length of the cake of soap 10, 
the extent of which is best illustrated by FIGS. 2 and 3. The mouth 14 of 
the cavity 12 is located at one end of the cake of soap 10. 
The reason for having the cavity 12 located off centre within the cake of 
soap 10 is to ensure that the soap remnant is entirely or at least partly 
used when the new cake of soap is worn through use. If the cavity were to 
be centrally located, the soap remnant will always be left when the new 
soap cake is worn. 
The cavity 12 is positioned a sufficient distance away from the 
longitudinal edges of the soap cake 10 to ensure that the wall surrounding 
the cavity 12 are of sufficient strength so that the cake of soap can be 
handled without damage to the cavity walls. 
The cavity 12 may be made by punching out, moulding or by any other 
suitable technique. 
In use, a cake of soap is worn down to a reasonable size preferably before 
it becomes too difficult to grasp or before it becomes too soft and tacky 
and forms the soap remnant 16. This is usually when the cake is worn down 
to about 5 to 15 per cent of its original size. Next a cake of soap 10 is 
then moistened so that the walls of the cavity 12 are sufficiently wet or 
the soap remnant 16 moistened or both. This is done in order to assist the 
adherence of the two pieces of soap to each other. The soap remnant 16 is 
then longitudinally inserted into the cavity 12. As shown at FIG. 4 when 
inserted, a portion 18 of the soap remnant 16 protrudes from the cavity. 
To lock the soap remnant 16 in place force is applied to the protruding 
portion 18 thereby forcing the soap remnant 16 within the cavity 12 and 
causing it to deform. This deformation fills the mouth portion of the 
cavity thereby forming a plug 20 which effectively seals cavity 12 so that 
the soap remnant does not become dislodged during use. 
It should be appreciated that various other changes and modifications may 
be made to the embodiment described without departing from the spirit and 
scope of the invention.