A controlled porosity composite sheet consisting of melt blown polypropylene fibrous webs 20 having spunbonded polypropylene fiber sheets 10 laminated on one or more sides thereof is a melt blown fiber when making a two layer composite sheet. The spunbonded web in contact with the metal roll 1 heated to 140 to 170 ° C. operating opposite the non-heating elastic roll 2 and in contact with the heated metal roll in the case of producing a three-layer composite sheet It is made by calendering the assembly of the component webs in such a way that the dtex value is less than 6 per sugar. Such composite sheets have Gurley-hil porosity of about 5 to 75 seconds, excellent mechanical and tear strength, high water vapor transmission rate and low liquid water transmission rate. They are particularly suitable for housewrap sheets and sterile cosmetic sheets. In the field of sterile packaging, they are far superior to medical papers used for the same purpose.
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