Chemically activated heat releasing pads, packs and plasters (supportive) for therapeutic or medical purposes; therapeutic or medical pads, packs and plasters (supportive); heating pads, patches, packs or plasters for medical purpose; pads, packs and plasters (supportive) used for physiotherapy; thermal packs for first aid purposes; pads, patches, packs and plasters (supportive) for relieving pains for medical purposes or therapeutic purposes