PHOTOCURABLE ADHESIVE, ADHESIVE SHEET, LAMINATE, AND DISPLAY

• Main Author: FUKUTA KATSUNORI
• Format: Patent
• Language: English; Japanese
• Published: 30.05.2024
• Subjects: ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; ADHESIVES; CHEMISTRY; DYES; LAYERED PRODUCTS; LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT ORNON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM; METALLURGY; MISCELLANEOUS APPLICATIONS OF MATERIALS; MISCELLANEOUS COMPOSITIONS; NATURAL RESINS; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; PAINTS; PERFORMING OPERATIONS; POLISHES; TRANSPORTING; USE OF MATERIALS AS ADHESIVES

To provide an adhesive, an adhesive sheet, a laminate, and a display which are excellent in transparency and capable of combining heat resistance and moist heat resistance with flexibility and windability.SOLUTION: A photocurable adhesive contains a urethane prepolymer (X) and a polythiol (Y). The urethane prepolymer (X) contains all structural units derived from the following (x-1)-(x-3): (x-1) an alicyclic isocyanate and/or an aromatic isocyanate; (x-2) a polyether polyol; and (x-3) a monool having an alkenyl group or a (meth)acryloyl group in the molecule. The photocurable adhesive satisfies all of the following (1)-(3): (1) the adhesive has a storage modulus at -20°C and 1 Hz of 1×105-1×106 Pa; (2) the adhesive has a storage modulus at 20°C and 1 Hz of 5×104-5×105 Pa; and (3) the adhesive has a storage modulus at 60°C and 1 Hz of 1×104-2×105 Pa.SELECTED DRAWING: Figure 1 【課題】透明性に優れ、さらに耐熱性及び耐湿熱性と、屈曲性及び巻き取り性の両立が可能な粘着剤、粘着シート、及び積層体、さらにはディスプレイの提供。【解決手段】ウレタンプレポリマー(Ｘ)およびポリチオール（Ｙ）を含み、ウレタンプレポリマー(Ｘ)は、下記（ｘ－１）～（ｘ－３）に由来する構造単位を全て含むウレタンプレポリマーであり、かつ、下記（１）～（３）の全てを満たすことを特徴とする光硬化型粘着剤。（ｘ－１）脂環族イソシアネートおよび／または、芳香族イソシアネート、（ｘ－２）ポリエーテルポリオール、（ｘ－３）分子内にアルケニル基又は（メタ）アクリロイル基を有するモノオール。（１）粘着剤の－２０℃、１Ｈｚでの貯蔵弾性率が、１×１０５～１×１０６Ｐａ、（２）粘着剤の２０℃、１Ｈｚでの貯蔵弾性率が、５×１０４～５×１０５Ｐａ、（３）粘着剤の６０℃、１Ｈｚでの貯蔵弾性率が、１×１０４～２×１０５Ｐａ。【選択図】図１