To develop bark-phenol formaldehyde resins（BPF）using phenolic components derived from Sugi bark, the curing behavior of BPF, which was prepared by blending bark extracts with commercial phenolic resins, was evaluated using differential scanning calorimetry（DSC）. Alkaline extraction of Sugi bark at high temperatures of 100℃, 140℃, and 170℃ revealed that the extraction yield of bark extracts increased with higher extraction temperatures. Furthermore, as the extraction temperature increased to 140℃ and 170℃, the average molecular weight of the phenolic components in the bark extracts decreased, indicating depolymerization. The peak temperatures of the DSC for BPF using the 140℃ and 170℃ extracts shifted to lower temperatures compared to phenolic resin alone, suggesting that these extracts participated in the curing reaction. However, such changes were not observed in BPF using the 100℃ extracts. Additionally, the reaction enthalpy（ΔH）increased with formaldehyde treatment of the extracts, implying an increase in the degree of cross-linking. With the addition of formaldehyde at 1.0 mol per 100 g of extract and treatment at room temperature, ΔH increased markedly.

We have developed a hybrid elastic instant adhesive using reaction-induced phase separation. This adhesive consists of a large amount of cyanoacrylate component and a small amount of modified silicone component. The cured adhesive forms domains of fast-curing and hard polycyanoacrylate and a matrix of slow-curing and flexible modified silicone. Due to the high content of cyanoacrylate, it cures quickly, while the modified silicone matrix provides flexibility. This product forms a soft and tough bond, making it resistant to vibration, impact, and thermal shock. Additionally, it is expected to offer improved productivity compared to other adhesives. These features are expected to contribute to faster bonding and improved durability in various fields such as automotive, electronic materials, and others.