In the 1930s, which British firm patented the Mentho-Lyptus formula and started making cough drops?

In 1893, the Hall brothers founded Halls in Great Britain to manufacture soaps and jams. Soon they began to produce candy products such as caramels and traditional British favourites like chocolate limes and humbugs. In the 1930s Halls invented its patented Mentho-Lyptus formula, using a combination of menthol and eucalyptus, and began producing its popular cough drops.

Halls is the brand name of a popular mentholated cough drop. Halls cough drops (categorized as a cough suppressant/oral anaesthetic by the manufacturer) are sold by the Cadbury-Adams Division of Cadbury, now owned by Mondelēz International, and have long been advertised as featuring "Vapor Action". Halls Brothers was acquired by Warner-Lambert in 1964. Production in Whitefield ceased in the late 1980s. When Pfizer acquired Warner-Lambert in 2000, the Halls brand came with the entire Adams portfolio (which included Trident gum, Dentyne, Chiclets and Freshen Up, among others). Two years later, Adams was bought out by Cadbury, who were subsequently purchased by Kraft foods, which was later restructured and renamed Mondelēz International - as of 2015, Mondelēz International owns the Halls brand worldwide.