Example 7
A Celgard EZ1590 microporous polypropylene matrix (15 μm thickness) is metalized on two sides via a vapor deposition process with aluminum metal to a sheet resistivity of between 0-500 Ω/sq. The metallization can be performed with patterning (mask, silk screening, etc.) associated with touch screen addressing technologies. A two sided patterning can be used for a “one layer” capacitive touch screen construction. The metalized microporous matrix can now be used in conjunction with a filler material to obtain the desired optical clarity properties. In this case, an optical adhesive with a refractive index matching the polypropylene matrix (i.e. NOA 148 from Norland Products) can be used to simultaneously fill the matrix and provide adhesive properties to the touchscreen glass surface, as well as the supporting layers below.