It would be desirable to improve upon the washing or disinfection capability of hydrogen peroxide-generating compositions at ambient to low operating conditions. The instant invention provides bleach compositions in which an activator is adsorbed into sodium perborate monohydrate, often in an amount of 20-40% w/w thereof. The invention permits liquid and consequently often low molecular weight activators to be readily employed in solid formulations. Preferred activators are selected from enol esters or gem-diesters, including vinyl benzoate, ethylidene benzoate acetate and divinyl adipate. The invention can also render N-acyl activators such as TAED more storage-stable.