If you're referring to the custom logo/header image you uploaded in Seller Admin > Edit Profile, that would be the same for all your checkouts regardless of which item(s) the buyer is purchasing. We don't have any way to change that logo depending on the item(s) being ordered.
If you'd prefer to just delete the logo, you can go to Seller Admin > Edit Profile > Upload Your Logo, and just use the Delete button on the logo uploader screen. When you do this, PayPal checkouts will show whatever Business Name you have entered in your PayPal Business account's profile settings.
