Excimer laser-induced photochemical modification and adhesion improvement of a fluororesin surface

Abstract

Modification of a selective area of a fluororesin surface was accomplished by using ArF excimer laser radiation and a boron complex with oleophilic or hydrophilic functional groups. The chemical stability of fluororesin is attributed to the presence of C-F bonds. The F atoms were abstracted by B atoms selectively from the area irradiated with excimer laser radiation and were replaced with the desired functional groups. In this modification, B(CH3)3 and B(OH)3 were used: a boron compound with methyl groups to generate an oleophilic surface, and one with hydroxyl groups to generate a hydrophilic surface. As a result, the resin surface exposed to ArF laser radiation becomes oleophilic or hydrophilic. Both samples were bonded to stainless steel plates with an epoxy bonding agent and the tensile shear strength was 1.2 x 107 Pa in both cases.

Area-selective nucleation of copper on fluorocarbon–resin surface using ArF excimer laser-induced chemical modification

“…In addition, this technique can be performed with safety and in the open air, with no environmental disruption and no need for vacuum system. 12 In conclusion, copper nuclei for area-selective deposition onto fluorocarbon-resin surface were formed using an ArF excimer laser and CuSO 4 aqueous solution. The ArF excimer laser photons were able to induce the defluorination effectively using the hydrogen atoms which were photodissociated from the water of the CuSO 4 aqueous solution.…”

Photoablation of Polymer Materials

“…With laser treatment in reactive atmosphere (e.g., hydrazine [100,101]) or under various liquids (e.g., B(CH 3 ) 3 [102,103]), the F--C bonds on the surface can be broken, CH 3 radicals or amino groups can be incorporated, allowing to apply a coating after laser treatment. This surface modification takes place without detectable ablation.…”

Protein adsorption on PTFE surface modified by ArF excimer laser treatment

“…We have photo-chemically incorporated both hydrophilic and hydrophobic groups, as well as metal atoms, on the PTFE surface by ArF excimer laser irradiation, without any physical damage [16][17][18][19][20][21][22][23][24]. In our previous studies, we incorporated desired functional groups or metal atoms onto the polymer surface using an excimer laser to generate a hydrophilic or hydrophobic surface and found that especially for PTFE, B, Al and H atoms were effective in defluorinating [16,17,21].…”

“…In our previous studies, we incorporated desired functional groups or metal atoms onto the polymer surface using an excimer laser to generate a hydrophilic or hydrophobic surface and found that especially for PTFE, B, Al and H atoms were effective in defluorinating [16,17,21]. Having studied the compatibility between the defluorinating atoms and a living body extensively, it was found that when using B and Al, their compounds remained on the modified surface and became impurities to cause rejections; however, no rejection occurred on the hydrophilic PTFE modified with H, i.e.…”

“…When the PTFE is irradiated with ArF excimer laser in the presence of water, the water is photo-dissociated to produce H and OH radicals, as in equation (1). At the same time, as the ArF laser photon energy (147 kcal/mol) is higher than the C F bond energy in PTFE (128 kcal/mol), the C F bond can also be photo-dissociated by the laser photon [16,21]. As indicated in equation (2), the H radical pulls out the F atom from the photo-excited C F bond to produce HF and the OH radical immediately combines with C to form C OH, which develops a hydrophilic property [20].…”