Figure 1 - Bulk Softness

Figure 2 - Surface Softness 

Tissue is a true consumer product and as such there are continuous demands to improve quality and performance.  One of the most commonly sought after improvements is the softness of the tissue.  Tissue softness is perceived by the consumer as the primary quality property, particularly in toilet and facial grades.

Many improvements can be achieved through furnish selection and process optimization but there is always a limit to what can be achieved.  These may be cost, productivity, or equipment limitations but there is a point where further improvements become difficult.  This is where softeners and debonders can help to further boost softness.

Before selecting a product, it is important to identify what aspect of softness needs to be improved.  There are two main softness properties:

Bulk softness (see Figure 1)

Surface softness (see Figure 2)

Overall softness is a combination of these two properties and it is important to identify which property needs to be improved before selecting a softener or debonder.

Softeners and debonders will have an effect on both properties but generally a debonder will have more of an impact on bulk softness and can help improve sheet flexibility while a softener will have more affect on the surface properties of the tissue.

The ProSoft® Softener and Debonder Technology range includes products that will improve surface softness and bulk softness as well as products that will combine these two benefits.

Mode of Action

Debonders work by separating fiber to fiber bonding sites through adsorption of cationically charged hydrophobic compounds attached to the fiber surface.  This will increase sheet flexibility but will also give a reduction in tensile strength.

Softeners work by plasticising, lubricating and conditioning of individual fibers and therefore lowering the coefficient of friction between the fibers.

The desired finished properties of the sheet will determine which product to use.  Please contact your local Hercules Representative to discuss product selection further.

Method of Application

Debonders are added internally to the stock system with fresh water dilution. This ensures good contact with the fibers and will maximize efficiency.  The actual dosage level will be dependent in fiber selection and the degree of softness improvement required.

Softeners can either be added internally to the stock system or sprayed onto the surface of the sheet prior to creping.  For internal addition the product should be diluted with fresh water for good fiber contact and maximum performance.  Products would be typically sprayed onto the felt supported sheet just prior to transfer onto the Yankee Cylinder.

ProSoft® Softener and Debonder Technology works hand in hand with Crepetrol® Creping Technology, the softener/debonder program should be matched to the crepe control program to ensure maximum benefits.

Recorded Benefits

Increased surface softness
Improved sheet flexibility
Enhanced bulk and caliper
Improved handfeel
Increased bulk softness