It would be mistake for you to understand that Japanese is written only in kanji.
Actually, quite a few non-native Japanese speakers want to try to make translation in kanji. But they are wrong.
You may be satisfied with these translations, but native Japanese speakers may not understand what it means.
They may decide that it's not Japanese but Chinese.
These translations are quite unnatural for native Japanese speakers.
If you write, 個人用電子計算機 instead of パソコン(パーソナルコンピューター), many Japanese people won't understand it correctly when you wanted to mention a personal computer. They wonder if it means a calculator of his or her own.
パソコン is definitely a Japanese word.
So is ミディアム・レア.
By the way, if you want to get kanji translations for tattoo instead of learning natural Japanese, you should go to the Chinese forum.
Natural wording in Japanese looks weird, funny and awful as the design for tattoo in many cases.