Foam bonding

A method of metering a foamed material across the lateral dimension of a surface of a moving substrate in a controlled manner, said method including the steps of:

• forming a foam material comprising a liquid and a gas;
• thereafter
• directing the foamed material under pressure into a receiving section of the interior compartment of an applicator unit above a partition means extending into said compartment, said interior compartment terminating at one end in a narrow, elongate metering flow gap having a depth up to about 60 mils;
• forming a single pocket of compressed air that extends laterally across the interior compartment by trapping air in the compartment between the partition means, walls of said compartment and an upper surface of the pressurized foamed material, said pocket of compressed air establishing a substantially uniform force along the upper surface of the foamed material across the lateral dimension of the compartment to thereby impart a substantially uniform force to the foamed material for metering it in a controlled manner uniformly through the narrow flow gap;
• and
• moving the substrate past the metering flow gap with the elongate dimension of said flow gap extending laterally across the width of the substrate surface, whereby a controlled quantity of the foamed material metered through the flow gap is deposited uniformly across the width of the substrate surface.