Oni no ho (黄丹袍)
"Oni no ho" is a ho (round-necked robe worn by members of nobility and the imperial court) of sokutai (traditional ceremonial court dress) costume, worn by a crown prince in the rituals. It was named after the color 'oni,' which is obtained by dying a cloth with gardenia and safflower.
According to 'The Garment Code' of "Yoro Ritsuryo Code," oni was determined as the color of 'koromo' (robe) of crown prince's reifuku (formal dress used for choga [retainers' New Year's greeting to the emperor] and the enthronement ceremony) and chofuku (the original model of sokutai). It is thought that this color might have originated from 'hanezu-iro' (hanezu red), a color which had been used before then.
While korozen no goho (a costume which an emperor puts on when he performs an important ritual), whose origin was shakoho (apricot-yellow robe made for the exclusive use of an emperor) of China, was imported in the early Heian period, the origin of oni no ho is earlier than that.
Although the crown prince's reifuku was replaced by a red kushofuku in the early Heian period (after choga was abolished in the middle of the Heian period, the crown prince's reifuku fell into disuse), oni no ho was continuously used for chofuku and the use of the eno-maru (a design in which mandarin ducks form a circle) pattern became common practice.
The use of oni no ho was suspended in the Muromachi period when the investiture ceremony of the Crown Prince was suspended and the heir to the Imperial Throne ascended the throne from the status of imperial prince.
The investiture ceremony of the Crown Prince was revived in the Edo period, starting with that of Imperial Prince Tomohito (the Emperor Higashiyama). However, in the beginning, it seems that a costume of reddish-brown color called "akairo no ho" was used, and its fabrics still exist in some places.
Akairo no ho' of the crown prince is seen in "Daiki"and so on, but it is unknown whether it was the another name of oni no ho or another thing (in fact, shufutsu costume of kebiishi [officials with judicial and police power], whose color was orange similar to oni, was called 'aka ginu' [red robe]).
Since the time of Imperial Prince Tomohito, the crest of a mandarin duck (only male) sitting inside the flower-shaped frame has been stylized and never changed till now.
According to the regulations in the late early-modern times, in winter, both Yamashina and Takakura families of emon-do (traditional technique for dressing up ceremonial costume) tailor a hoeki no ho (robe with a round collar, stitched sides and a ran, worn by the emperor and high-ranking officials) after coming of age with yellow hiraginu silk for lining, while tailoring a ketteki no ho (open sleeve seams outer robe) before coming of age with oni silk, same color as lining. The crests were lined up vertically and horizontally, and they were not staggered stepwise as the case of ordinary cloth of shozoku. The above was same in the case of Koro zen (yellowish brown color for emperors).
In the case of ketteki, crests of eno-maru are placed closely on the ground that it is the one for a minor (the size of crests were generally small and they were closely placed in the case of shozoku for the young). A kataji-aya fabric, a sanmai-aya fabric on which crests are arranged by a rokumai-aya fabric, was used as the material of ketteki for winter-use. In the case of ketteki for summer-use, a kind of sha (silk gauze) called "koku" (禾=>系) is used without lining.
The above system basically continued to exist up to the recent times, but the crests were not placed so closely as in the early-modern times even in the case of ketteki. A proposal to change eno-maru for tsuru-maru (the design of crane) was made before the investiture ceremony of Imperial Prince Hirohito (the Emperor Showa), but it was dismissed.