ML-based image recognition has been employed in various fields and is expected to be widely applied in the chemical field. Inokuma et al. predicted the mixing ratios of various solid mixtures using image-based ML, where a model trained on 300 images could determine the weight ratios of each sugar and dietary salt in their experimental mixtures . Jirayupat et al. employed a combination of image-processing and ML methods to identify the multivariate chemo-/biomarker features of analytes from chromatography-mass spectrometry data . These studies have demonstrated that supervised-learning methods can be used for image-processing and recognition in chemistry. However, it is unclear whether unsupervised-learning methods can be used in the chemical field.