藥典: Ascorbic Acid(抗壞血酸)

since: 2018/08/12
update:
2018/08/12

reference:
1. The Darkroom Cookbook 4th Edition
2. 抗壞血酸 - 維基百科,自由的百科全書


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Acid, Ascorbic(抗壞血酸) (p.194)

Synonyms: L-Ascorbic acid, 3-oxo-L-gulofuranolactone(enol form), Vitamin C.
同義詞:L-抗壞血酸,3-氧代-L-呋喃呋喃內酯(烯醇型),維生素C.

Appearance: White crystals.
外觀:白色晶體。

Uses: As a developing agent and as a preservative.
As a developing agent it acts more vigorously at higher alkalinities.
It is slow to get started but gives images with low fog.
At low alkalinities, in combination with metol or Phenidone, ascorbic acid is an active, long-lasting developing agent.
用途:作為顯影劑和防腐劑。
作為一種顯影劑,它在更高的鹼度下更有活力。
它開始很慢,但提供低霧圖像。
在低鹼度下,與 metol 或 Phenidone 組合,抗壞血酸是一種活性的,持久的顯影劑。

Substitutions: The pure vitamin C powder, available from health food stores, can be used.
Or you can use the tablet form and crush it to a powder with a mortar and pestle before adding.
Do not weigh the tablets as insoluble starch binder adds weight. Just add up the vitamin C contents
(i.e., a 500.0 mg tablet = 0.5 grams of vitamin C, a 1000.0 mg tablet = 1.0 gram.).
To remove the starch binder, filter the developer solution through a coffee filter(do not use the filter for coffee afterwards!).

替代品:可以使用可從健康食品商店獲得的純維生素C粉末
或者你可以使用片劑形式,然後在加入前用研缽和研杵將其粉碎成粉末。
不要稱重片劑,因為不溶性澱粉粘合劑會增加重量。 只需加入維生素C的含量即可
(即,500.0mg片劑= 0.5克維生素C,1000.0mg片劑= 1.0克)。
要去除澱粉粘合劑,請通過咖啡過濾器過濾顯影劑溶液(之後不要使用咖啡過濾器!)。


Sodium ascorbate or sodium isoascorbate can also be substituted.
Use 1.125 times the weight of vitamin C (11.25 grams of either is equivalent to 10.0 grams of ascorbic acid).
Hydroquinone can also be replaced by vitamin C.
(see Hydroquinone; Sodium ascorbate; and Sodium isoascorbate) 
抗壞血酸鈉異抗壞血酸鈉也可以被取代。
使用維生素C重量的1.125倍(11.25克,相當於10.0克抗壞血酸)。
對苯二酚也可以被維生素C取代。(參見對苯二酚;抗壞血酸鈉;和異抗壞血酸鈉)


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