UV-curable hyperbranched polyurethane （UV-HBPU） containing carboxyl groups was synthesized from isophorone diisocyanate （IPDI）, diethanolamine （DEOA）, polyethylene glycol （PEG-400）, hydroxyethyl acrylate （HEA）, and 2,2-his （hydroxymethyl） propionic acid （DMPA）. The UV-HBPU was used as a negative-type photoresist for a printed circuit board （PCB）. Fourier-transform infrared spectroscopy （FTIR） and proton nuclear magnetic resonance （1HNMR） spectroscopy of UV-HBPUs indicated that the synthesis was successful. Differential scanning calorimetry （DSC） and thermogravimetric analysis （TGA） showed that the thermal stability of the UV-HBPUs decreased as the HEA content increased. The polymer exhibited excellent photoresist properties, and the resolution of circuits based on this negative-type photoresist reached 10 μm.
