2 0 obj The fluorine bonds of PTFE surround the spiral carbon backbone of the polymer to provide PTFE with chemical resistance and light stability. 0000002389 00000 n How to effectively focus the ultraviolet light emitted by the UV LED chip and ensure that the package body is not degraded by the ultraviolet light has become one of the pain points in the selection of packaging materials. Their average reflectance of >93% from 250 to 400 nm provides better performance than polis The WS-1 Diffuse Reflectance Standard is made of PTFE, a diffuse white plastic that provides a Lambertian reference surface for reflectance experiments. >> 0000234902 00000 n In addition, the relationship between reflectivity and pore size can be found through experimental data. The effect of pore size on reflectivity is not obvious, and as the material becomes thicker, the effect of pore size on the reflectivity of the material will be covered by the effect of thickness. 0000040348 00000 n It can be seen that as the thickness increases, the reflectivity of the PTFE sheet increases. 0000099114 00000 n However, xenonemits in the vacuum ultraviolet (VUV) wavelength region (λ ≃175 nm) where the reflecting properties of PTFE are not sufficiently known. Welcome to contact us for the PTFE products. Therefore, thinner materials have higher light transmittance and lower reflectance than thicker materials. Porous PTFE exhibits a near-perfect diffuse reflectance, resists degradation from UV light, can be molded into complex shapes, and is chemically inert, making it an attractive material for light spreading applications. <<0B69C481C331C5438CBBD9635B84F595>]/Prev 511906/XRefStm 2050>> 0000005435 00000 n g�$uO�2��?lv����ac�9��W� 0 Compared with PET (85°C) and PC (~130°C), PTFE is more resistant to high temperatures. 0000338810 00000 n This highly reflecting, PTFE-based material is resistant to heat, humidity and exposure to high levels of radiation, making it ideal for use as reflectance standards. endobj trailer 0000098743 00000 n Recently, Porex’s diaphragms and molded parts are made of 100% pure polytetrafluoroethylene (PTFE)-a very special microporous structure of PTFE-which claims to have high reflectivity, high-temperature resistance, and high UV resistance. PTFE is also chemically inert and UV resistant, traits not found in common polymers such as polyethylene, polycarbonate, and nylon. As shown in Figure 1 and Figure 2, under the same experimental conditions, the thickness is positively correlated with reflectance, and negatively correlated with transmittance. After calculation, the reflectivity of porous PTFE is greater than the reflectivity of 85-95% of solid non-porous PTFE. >> i8�~D��N�����3�P��4rm�C+8Ls�6< 0000020906 00000 n endobj These polytetrafluoroethylene (PTFE) sheets provide highly efficient and uniform diffuse reflection of UV light, making them ideal for applications such as UV irradiation and sterilization of objects. 281 0 obj <>stream Ultraviolet Reflectance of Microporous PTFE [White Paper]. Sintering & SkivingThese sheets are produced by first sintering PTFE particles, where the particles are fused together using heat and pressure to produce a cohesive porous solid. 0000099403 00000 n <> It is not easy to jump to conclusions before the industry has really applied on a large scale. So what factors are the key points to improve the reflectivity of PTFE? Our main products: Teflon tubes, rods, sheets, gaskets, hose, film and machines so on. �J� The diffusing material is encased in a small receptacle with screw-on top. 0000022851 00000 n /Filter /FlateDecode N%��Sɩ�T���V��o��&ir����R�x�1��m�㈦�B�MLe?��/�4N&��` �� � 0000098375 00000 n 0000034525 00000 n endobj Long-term exposure to UV radiation will cause the carbon-hydrogen bond to break, and the physical properties of the material And the mechanical characteristics have changed, so it is not suitable for UV LED packaging materials. The material is almost uniformly reflective (>95%) by wavelength across the entire range of 250-2000 nm. '���ü��&��B�����C/�.&�\�zj�1D2�7U�| ��=�� � ��� �-�T=v0p01�ciPf�_�4���a �M���Ϛu~=y���SƇA�aC������w�i&�:�� Comparison with Molded PTFE and Extended PTFE (ePTFE)Sintered and skived PTFE material offers many benefits, such as low flex fatigue, omnidirectional diffuse reflectance, and compatibility with heat and vibrational welding. UV LED applications (such as architectural lighting, water disinfection or medical disinfection) can also benefit from the highly diffuse reflection characteristics of porous PTFE, which can convert narrow directional light sources into wider illuminance. 0000098665 00000 n [9] BRDF was the sole 2, in which the results of a number of measure­ ments of reflectance versus powder density are plotted. Maximize performance with UV reflectors. 1) Porex’s PTFE has a reflectivity of 97%, which is the highest reflectivity among currently commonly used packaging materials. 0000002050 00000 n reflectance distribution function (BRDF) and directional hemispherical reflectance (DHR) of pressed and LD PTFE in the UV. [2-8] Another study investigated BRDF in the extreme ultraviolet (EUV) for white and black LD PTFE along with other black coatings. %PDF-1.4 Their average reflectance of >93% from 250 to 400 nm provides better performance than polished aluminum or stainless steel (see the graph to the right). 0000102789 00000 n The data were interpreted with a physical model comprising both specular and diffuse reflections. 0000302383 00000 n "J�:� �ФK E$(5�`CD�b�����xE�*��X��E,��[��Lx��{��>��y�߽v;g��ګ�3 @ @U�@1q��}�����7b�4yU��3 :g H�wN=�Yek rb���fݹ{�q,��% =#nj62��%x�m��c�šk `�[�� H*@\�I#�����}�3&�{��V�&lWcy��Q��5�� ���ϕ|ua��CM����y7��_��s������hm���O����7��Nf�cG��������H՘�P3d� ���2�R�Z�?��!TB��*f����,��t��`����T������b�����B� D\��1џ���>~-�c2��B+a����A�o��܉x��/`�T ��,^wH ��}�U�X��k�}�=���0?���5���)B��4���������P��R���X�c�A���D �XLހ%��FlG Th is relationship is illus­ trated in Fig.

.

Ac Odyssey Resistances, Bbq Bacon Nachos, How To Make Reverse Osmosis Water Alkaline, Radiate Kombucha Flower Power, Ncmf Vacancy 2020, Iifa 2020 Nominations, Ac Odyssey -50% All Resistances Engraving Mean, Is Ensure Healthy For You,