If I import products with csv the image is not visibly at the category page. If I go to the product page the image is showing. How is that possible. base, thumbnail, small image and swatch are fine.
I use magento 2.1.6
The category pages use the flat index tables, the product page not. So your index is not up to date.
Is your index configuration "update on save"? Then the product import was not updated by the import and you need to update it manually with this shell command:
bin/magento indexer:reindex catalog_product_attribute
Is it "scheduled"? Then make sure that your cronjob is running and give it some time to update. It still might be necessary to update the index as above.
You may be a victim of this bug. Try running the command:
php bin/magento catalog:images:resize.