These days, more consumers are asking formulators to “Do me a solid,” and personal care companies are happy to oblige. That's because there's growing demand for solid shampoo, soap and even toothpaste as shoppers seek to reduce packaging waste, according to Singapore Tatler.  The authors note that solid formats contain little or virtually no water, which makes them easier to create with fewer ingredients. In addition, solid formats are easier to pack and travel with, whi...