I first found out about Junko Hirotani （広谷順子）after leafing through a copy of "Nihon no Josei Singer-Songwriters" (thanks most kindly, JTM) and coming across her 1980 2nd album, "Blendy" (I did enjoy drinking its iced coffee namesake years later during the torrid summers in Tokyo). So I heard a few of her tracks from the album on YouTube and enjoyed them as light pleasant pop.
Then, I went all the way back to her debut single, "Michi" (The Road) which came out in February 1979, along with the Side B song, "Kagirinai Sora" (The Limitless Sky). For a cool and sunny Sunday like today, these two fit the bill rather nicely. There's a countryside freshness to "Michi" that reminds me of some of the earlier stuff by Ruiko Kurahashi （倉橋ルイ子）who would make her own debut a couple of years later in 1981. As for "Kagirinai Sora", there seems to be a bit of early Taeko Ohnuki （大貫妙子）in that melody. Unfortunately, I don't know who created the B-side, but Michio Yamagami and Kunihiko Murai （山上路夫・村井邦彦）were responsible for "Michi" according to the notes for the YouTube video. The single was also a tribute to 1979's International Year of the Child.
From the time that she was 3 years old to her high school days, Hirotani had been playing piano, but then decided to start up her own band with which a lot of The Carpenters' discography was used as performance material. In June 1976, she won the Grand Prize and a prize in composing at the Inter-College Original Song Contest, and in the following month, she signed a contract with Alfa Music, the same company that later signed up the Yellow Magic Orchestra and Circus.
As a solo performer, she has released 6 albums and 3 singles, but has mainly been busy as a composer and backing vocalist for a number of other singers such as Wink, SMAP and Akina Nakamori（中森明菜）.