To provide a fracture-visualization sensor capable of visualizing the fracture behavior of a composite material and a composite-material fracture-visualization system using the fracture-visualization sensor.

A first luminescent film including a mechanoluminescent material is provided on one surface of a composite material. The first luminescent film has a maximum stress per unit of cross-sectional area within the range of 19-43 N/mm.sup.2.

To provide a fracture-visualization sensor capable of visualizing the fracture behavior of a composite material and a composite-material fracture-visualization system using the fracture-visualization sensor. A first luminescent film including a mechanoluminescent material is provided on one surface of a composite material. The first luminescent film has a maximum stress per unit of cross-sectional area within the range of 19-43 N/mm.sup.2.

Triboluminescent materials that generate emission of light in response to mechanical stimulus attract significant attention due to their applications in development of “smart materials” and damage sensors. Among metal complexes, rare-earth europium and terbium complexes are most widely used, while there is no systematic data on triboluminescence in more readily available and inexpensive Cu complexes, with only a few scattered examples reported in the literature. We report a new family of photoluminescent Cu—NHC complexes that show bright triboluminescence (TL) in crystal state visible even in ambient light under air upon grinding or crushing the crystalline sample. Moreover, when these complexes are dispersed into amorphous polymethylmethacrylate (PMMA) films even at small concentrations, TL is easily observed. In Cu-containing polymer films, surrounding gas discharge is likely involved in excitation of brightly luminescent Cu—NHC complexes. Observation of TL in polymer films overcomes limitations of using crystalline phase for mechanoresponse and opens up possibilities for development of mechanoresponsive coatings and materials based on inexpensive metals such as Cu.

Triboluminescent materials that generate emission of light in response to mechanical stimulus attract significant attention due to their applications in development of “smart materials” and damage sensors. Among metal complexes, rare-earth europium and terbium complexes are most widely used, while there is no systematic data on triboluminescence in more readily available and inexpensive Cu complexes, with only a few scattered examples reported in the literature. We report a new family of photoluminescent Cu—NHC complexes that show bright triboluminescence (TL) in crystal state visible even in ambient light under air upon grinding or crushing the crystalline sample. Moreover, when these complexes are dispersed into amorphous polymethylmethacrylate (PMMA) films even at small concentrations, TL is easily observed. In Cu-containing polymer films, surrounding gas discharge is likely involved in excitation of brightly luminescent Cu—NHC complexes. Observation of TL in polymer films overcomes limitations of using crystalline phase for mechanoresponse and opens up possibilities for development of mechanoresponsive coatings and materials based on inexpensive metals such as Cu.

A stress luminescence measurement device according to a first aspect is provided with a load application mechanism configured to deform a sample by applying a load to the sample, a light source configured to emit excitation light to a stress luminescent material 2 arranged on a surface of the sample, a camera configured to image luminescence of the stress luminescent material, and a controller configured to control the load application mechanism, the light source, and the camera. The controller acquires a deformation state of the sample at the imaging timing by the camera and stores the acquired deformation state of the sample in association with the image captured by the camera in a memory.

A stress luminescence measurement device according to a first aspect is provided with a load application mechanism configured to deform a sample by applying a load to the sample, a light source configured to emit excitation light to a stress luminescent material 2 arranged on a surface of the sample, a camera configured to image luminescence of the stress luminescent material, and a controller configured to control the load application mechanism, the light source, and the camera. The controller acquires a deformation state of the sample at the imaging timing by the camera and stores the acquired deformation state of the sample in association with the image captured by the camera in a memory.

Mechanoluminescent devices and articles, such as wearable articles, that include mechanoluminescent devices. The mechanoluminescent devices may have a lateral type architecture or a vertical type architecture. The mechanoluminescent devices may be sensors, including pressure sensors.

Mechanoluminescent devices and articles, such as wearable articles, that include mechanoluminescent devices. The mechanoluminescent devices may have a lateral type architecture or a vertical type architecture. The mechanoluminescent devices may be sensors, including pressure sensors.

Mechanoluminescent devices and articles, such as wearable articles, that include mechanoluminescent devices. The mechanoluminescent devices may have a lateral type architecture or a vertical type architecture. The mechanoluminescent devices may be sensors, including pressure sensors.

Mechanoluminescent devices and articles, such as wearable articles, that include mechanoluminescent devices. The mechanoluminescent devices may have a lateral type architecture or a vertical type architecture. The mechanoluminescent devices may be sensors, including pressure sensors.