Lub kaus lub hnub, tseem hu ua parasol, yog lub kaus siv los thaiv lub hnub ncaj qha thiab tiv thaiv ultraviolet (UV) rays. Qee cov khoom kuj muaj kev tiv thaiv los nag. Kev tiv thaiv hnub ci yog ua tiav los ntawm txheej txheej lossis siab - ntaub ntom ntom. Lub teb chaws tus qauv GB/T 23147-2018 qhia tias UV-cov khoom tiv thaiv yuav tsum ua tau raws li cov cai ntawm UPF > 40 thiab UVA transmittance < 5%, nrog siab- cov khoom zoo ncav cuag UPF 50+. Cov khoom siv tiv thaiv yog feem ntau polyester lossis dub-coated ntaub. Raws li kev siv, lawv tau muab faib ua cov kaus mom tuav thiab cov kaus ruaj khov: cov kaus mom tuav tau hais txog kev txav mus los thiab siv cov khoom siv hnyav xws li carbon fiber; tsau umbrellas hais txog cua tsis kam, nrog tav ua los ntawm cov ntaub ntawv xws li steel thiab aluminium alloy.
Sun umbrellas tuaj yeem taug qab mus rau lub hnub tiv thaiv cov cuab yeej siv los ntawm cov neeg Iyiv thaum ub, thiab lawv siv tau pib hauv Suav teb thaum Qing Dynasty. Niaj hnub nimno hnub umbrellas maj mam ua nrov nyob rau hauv lub xyoo pua 20th. Hauv xyoo 2013, Banxia tau tshaj tawm ob lub - txheej dub- txheej hnub ci, siv LRC txheej tshuab kom ua tiav 99% UV thaiv tus nqi. Nrog kev txhim kho kev noj qab haus huv, kev lag luam tab tom txhim kho rau kev tshwj xeeb: ultralight umbrellas hnyav dua 100 grams thiab txais yuav carbon fiber thiab honeycomb qauv tsim; smart sun umbrellas integrate solar charging technology, xws li Anker SOLIX solar umbrella nruab nrog perovskite roj teeb thiab IP67 waterproof muaj nuj nqi. Xyoo 2023, Suav lub hnub lub kaus lag luam tau mus txog US $ 327.96 lab, suav txog 7.82% ntawm lub lag luam thoob ntiaj teb.