Requirements for Unity of Application - Japan Patent Office

[Example 18]
[Title of the Invention]
Bond for molding and coated sand for molding
[Claims]
1. A bond for molding, wherein polyacrylamide is dissolved in water or quick-drying solvent.
2. Coated sand for molding, which is covered with the bond for molding whereby
polyacrylamide is dissolved in water or quick-dry solvent.
[Excerpt from Detailed Description of the Invention]
This invention mainly relates to a bond for molding used for die-casting, like light alloy
castings, where the temperature of the hot water for pouring is relatively low, and coated sand
for molding which is covered with said bond.
Though a light alloy casting is generally manufactured by die-casting, the mold used for the
core is manufactured by blowing sand usually coated with phenol resin and/or the like in a
model die. In the case of the light alloy casting manufactured by using thermo-setting synthetic
resin as a bond, due to the low temperature (e.g. about 700℃,) of the hot water for pouring, it is
possible that the thermal dematter of the bond made from thermo-setting synthetic resin may be
insufficient and that the core may also be hard or unable to be extruded because the
polymerization of the bond is conversely accelerated. The advantage of the present invention,
wherein poly-acrylamide is dissolved in the solvent, is excellent in a number of respects,
including strength, heat resistance, disintegration characteristics and productivity.
[Explanation]
Though the technical fields of the specified invention (Claim 1) and the related invention
(Claim 2) are respectively “a bond for molding” and “coated sand for molding”, it is highly
appropriate that the art of the former should be applied to the technical field of the latter,
because the sand for molding is covered with the bond. Accordingly, the technical fields of both
inventions are technically and directly associated with each other, and the industrial fields of
application of them are also the same.
In addition, a bond for molding which is a new matter corresponding to the problem to be
solved of the specified invention is equivalent to the substantial part of the matter in the claim of
the related invention; therefore the substantial parts of matters in the claims of the two
inventions are the same.
[Concerned Section]
Patent Law Section 37(ii)
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