Patent ID: 7695794

Claim:
A method comprising: a) mixing a plurality of bicomponent filaments 1 which comprise a component 11 and a component 12 with a plurality of bicomponent filaments 2 which comprise a component 21 and a component 22 wherein iα) at least bicomponent filaments 1 exhibit a core/sheath geometry wherein component 11 represents the core and component 12 represents the sheath, or iβ) at least bicomponent filaments 1 exhibit a side by side geometry wherein component 11 represents side 1 and component 12 represents side 2, or iγ) at least bicomponent filaments 1 exhibit an islands in the sea geometry wherein component 11 represents the islands and component 12 represents the sea, ii) the component 11 exhibits a melting temperature T m (11) and the component 22 exhibits a melting temperature T m (22), iii) the component 12 exhibits a melting temperature T m (12), the component 21 exhibits a melting temperature T m (21), and T m (12) is higher than T m (21), and iv) the melting temperatures of component 11 and component 22, and the melting temperatures of components 12 and 21, obey a relationship in which T m (11) and T m (22)>T m (12)>T m (21), and producing a basic fibrous layer in which bicomponent filaments 1 contact bicomponent filaments 2 at zones of overlap, and b) heating the basic fibrous layer at a temperature for nonwoven production T np , which obeys a relationship in which T m (12)<T np <both T m (11) and T m (22), until component 12 and component 21 melt at the zones of overlap and then cooling below T m (21) resulting in a bonded nonwoven.