Yas droppers feem ntau yog tsim los ntawm polyethylene (PE) los yog polypropylene (PP). Vim lawv cov tshuaj lom neeg ruaj khov, tiv thaiv corrosion, thiab yoog raws, ob cov ntaub ntawv no tau siv dav hauv ob chav kuaj thiab kho mob. Polyethylene droppers muab siab transparency, ua rau lawv zoo tagnrho rau kev soj ntsuam cov dej ntws, whereas polypropylene droppers muaj superior kub kuj thiab muaj peev xwm tiv taus kom tsis muaj menyuam cov txheej txheem. Kev tsim cov yas droppers ua qhov tseem ceeb ntawm kev tswj xyuas cov kua ntim dej; lawv feem ntau muaj cov cim kawm tiav, nrog cov npoo ntawm qhov yuam kev nruj me ntsis tswj kom tsis pub dhau 0.05 ml. Lawv qhov xwm txheej pov tseg tiv thaiv kev sib kis -, yog li ua kom muaj kev ua raws li cov qauv kev huv huv hauv chav kuaj. Tsis tas li ntawd, cov hnab yas tuaj yeem hloov kho kom tau raws li cov kev xav tau tshwj xeeb- xws li cov peev txheej sib txawv (xws li 3 ml txog 10 ml) lossis suav nrog cov ntawv luam tawm - ua raws li cov kev xav tau tshwj xeeb ntawm ntau hom ntawv.
Cov khoom siv tseem ceeb siv hauv kev tsim cov yas droppers yog tsawg- ntom polyethylene (LDPE), txawm hais tias lwm cov ntaub ntawv xws li PE thiab PET kuj nquag ua haujlwm. Lawv cov txheej txheem ntau lawm feem ntau siv extrusion tshuab moulding tshuab.