Laser-induced graphene (LIG) presents a promising route toward next-generation smart textiles by enabling direct patterning of conductive materials onto textiles through a single-step laser writing process. In particular, femtosecond laser-based fabrication offers high-resolution processing without damaging substrates. This review summarizes LIG formation mechanisms, laser manufacturing parameters, physical/chemical characteristics, electrical, thermal, and optical properties of LIG. Furthermore, it categorizes representative applications including biosignal monitoring, energy storage, thermal regulation, optical absorber, and extraterrestrial adaptability, all based on textile-integrated LIG. With its porous morphology, high conductivity, and structural versatility, LIG offers outstanding multifunctionality for smart textile applications. Future research should explore precise functional tuning of LIG through laser parameter optimization, accurate characterization of LIG, and advanced smart textile applications.

Recently, various attempts have been made to apply the additive manufacturing technology directly to fabricate a product. In this regards, the industry is focusing on the multi-material additive manufacturing technology that can processes multiple materials simultaneously. This study is about the fabrication of a 3-dimensional circuit device (3DCD), based on the multimaterial additive manufacturing technology, which is combination of the material extrusion and the direct writing processes. The multi-material additive manufacturing system was developed based on the commercial multi-head FDM system. In addition, a contact type nozzle for the dispensing of the conductive material in the direct writing process is proposed. The 3-dimensional circuit device in which circuit elements are arranged on several layers was fabricated successfully, based on the presented multi-material additive manufacturing system.