التعاون

فنون

الجمال والعناية

حِرَف

الثقافة والتاريخ

ترفيه

البيئة

الطعام والمشروبات

الهندسة العكسية

العلوم

رياضة

التقنية

الأجهزة القابلة للارتداء

Polypropylene Felt: a Spunbonded Web, Kinney 1967

George Allison Kinney (Du Pont) · Public domain (US patent)

أنشأه

Tex

18. أكتوبر 2026

Polypropylene Felt: a Spunbonded Web, Kinney 1967

A polypropylene felt made without weaving or needling: hot filaments are spun, pulled down by an air jet, given an electric charge so they spread apart, and laid in loops on a moving table until they form an even sheet. Kinney's patent (Du Pont, US 3,338,992, 1967) gives every setting for polypropylene. The corona runs at 20 to 25 kV: keep clear of it while it is live. The picture: the patent's own Fig. 1 (the process) and Fig. 7 (the web).

متقدم

1 day

التعليمات

Melt and spin

Melt polypropylene of melt index 10 in a screw extruder, no hotter than 290 °C. Meter it at 12 g a minute through a 1/4 in. sand filter and a 20-hole spinneret (holes 0.015 in. across): pack block 275 °C, spinneret 260 °C.

المواد لهذه الخطوة:

حبيبات البولي بروبيلين500 غ

الأدوات المطلوبة:

باثق البلاستيك

فوهة الغزل

مقياس الحرارة العالية

ميزان ذو كفّتين

قفازات جلدية

Quench

Cool the bundle of filaments in a 6 in. quench chimney blowing 40 cubic feet a minute of room air in from the side.

الأدوات المطلوبة:

ضاغط هواء

Draw with the air jet

Lead the bundle 72 in. down into an air draw jet run at 25 psi: it pulls the filaments with about 3 g of tension and stretches them.

الأدوات المطلوبة:

فوهة السحب الهوائي

ضاغط هواء

مقياس ضغط

Charge the filaments

8 in. above the jet, let the filaments brush a 1 1/4 in. bar turning at 10 rpm, with a four-point corona 5/8 in. from it at minus 20 to 25 kV (100 to 150 µA). The charge pushes them apart. Keep clear while it is live.

الأدوات المطلوبة:

وحدة شحن بالهالة (كورونا)

Lay the web

Catch the filaments on a grounded 47 in. square table that moves 26 in. a minute one way and 570 in. a minute the other. Each layer weighs 0.5 oz per square yard; lay several for each sheet.

الأدوات المطلوبة: