Current and Past Technologies for Headliners Including Acoustics, Recycling and Safety 980951
Headliner technology will be presented in this paper. Older established technologies such as cut & score, fiberglass, hardboard and resinated cotton are still used because of their proven reliability and low cost. But newer processes including polyester, natural fiber, Tramivex™ and urethane offer reliability, structure, acoustic performance and some recyclability. Fiberglass has always been a leader in acoustical performance but has breakage and handability issues in the assembly plants.
This paper will be divided in four sections. The first section discusses manufacturing processes for headliners covering current and past. It also covers the materials used and types of facing. This section will state why headliner technology used in the USA is different than Europe or emerging markets.
Second section describes acoustics. It will explain performance as related to material types. Porosity, cell type, fiber length and diameter is explained as it relates to the absorption of sound. The relationship between acoustics and construction will be discussed. Testing methods such as impedance tube, reverberation room and vehicle testing are explained and applied.
Section three discusses the need for recycling and preferred materials. The future policy of auto companies may include shipping headliners to the supplier upon disposal/dismantling of automobiles. This will force manufactures to think recycling or they will have to pay for headliners to be sent to landfill.
The final section will discuss the new head impact requirement in the USA. This section will discuss the need to minimize HIC (head injury criteria) with the use of foam or other energy absorbing materials.