Launchpad shows a fade effect anytime it is opened or closed. If you want to access Launchpad a little bit faster, it’s possible to disable the fade effects. Use the following Terminal commands:
defaults write com.apple.dock springboard-show-duration -int 0
defaults write com.apple.dock springboard-hide-duration -int 0
Restart the dock, to make changes affect:
killall Dock
Re-enable launchpad fading effect:
defaults delete com.apple.dock springboard-show-duration
defaults delete com.apple.dock springboard-hide-duration