How does loot bonus affect mob drops?

I am trying to get multiple rare items from rare mob and I was wondering how does the loot bonus (not loot quality) affect drops from mobs (specifically crafting ingredients)?
If I will have more loot bonus does it mean I will have higher chance of dropping rare items or if I will have the same chance but rather will drop more items such as 2 or more from one mob?
Also, is there a soft cap on loot bonus for mob drop only?

 

Loot bonus increases the drop chance. If you used a loot bomb it would drop 2 at a time.
I don't know if there is a soft cap.

 

there's no soft cap for mobs - the more lb you have, the higher chance there is for a mob to drop its ingredient(s)

also worth mentioning that lb & lq are treated as the same thing when it comes to ingredients, so they're essentially added together.