摘要 |
A valve member comprising a lower support portion and an upper seal portion. The support portion is made of a relatively rigid plastic and the seal portion is made of a relatively soft plastic. The two plastic portions are integrally merged to form a single piece valve member. The valve member may further include an upper support portion which is formed of a relatively rigid plastic and is integrally merged with the seal portion. The method of making the valve member using a mold in the shape of the valve member, comprises pouring the material forming one of the portions into the mold while in a liquid or molten state, and then pouring the material forming another of the portions into the mold in a liquid state onto the first portion. The two portions merge or diffuse along the interface between them and, when cured, form an integral unit. In an embodiment where a third portion is provided, the third portion, while the materials are in lqiuid state, is poured and becomes merged and integrated with the first two portions.
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