received by the International Bureau on 15 February 2016 (15.02.2016)

1. A sealing rib, characterized by:

- The pattern of the continuous sealing material and the rib around the body, to ensure proper sealing in all positions between full open and completely closed;

- The shape of the profile, according to specific dimensions, to ensure that the

deformation of the rib when squeezed towards the valve body increases the sealing surface, while still allowing a smooth rotation of the valve core at the same time;

- The depth and the shape of the sealing material filling the groove in the

polypropylene core, to ensure enough elasticity of the sealing material to deform to create a large enough sealing surface, while at the same time transferring some of the rigidity of the valve core to the sealing material, to ensure adequate sealing.

2. A sealing method for injection molded polypropylene plastic valves, through the use of a single operation double injection process, to shape the polypropylene valve core of the valve, in the first injection stage, and, then, the application of a thermoplastic elastomer sealing material to the surface of the polypropylene valve core, in the second stage, thus avoiding manual handling between the stages, such method being characterized by the following steps:

- The use of double injection method to avoid manual handling of the Valve Body (2) between the first and the second injection stage;

- The sealing material, which is adhered to the surface of the valve core, is creating a continuous sealing barrier, where there is interference between the sealing material and the valve body;

The actual sealing is made by a protruded sealing rib at the edges of the area of the sealing material;

- The elastomer sealing rib, which will seal against the inner surface of the valve body, is carefully measured to ensure proper sealing in all open / closing stages, while at the same time not adding too much friction between the parts;

This way proper sealing is achieved, without having to increase the torque required to open and close the valve;

As a result, the valve core and the sealing material are made as one part in one single process, but with two separate injection stages.