TECHNICAL PAPERS SECTION
Tel (856) 354-2292
Email: paulhoffman@paulhoffman.com
TECHNICAL PAPERS
The sections below contain the complete text, abstract, or summary of those papers written by me that best represent my experience and philosophy about tissue-and-towel-weight webs. They all have several important and seldom-recognized threads in common. First, they posit that paper density is the best indicator of the most important tissue properties: bulk, water absorptive capacity, and some components of softness (bulk softness and cushioniness). Second, they assume that these properties, as well as the performance of Paper Machines, can best be displayed on a strength-density diagram, which is for paper what the pressure-volume diagram is for gases. Third, they indicate that the above properties are additive: the weight average rule applies. However, these are not merely assumptions; the articles also use examples to prove these points. Please contact me for the complete texts.
While reading the texts, please be aware that, unless otherwise stated in the text, the term "Bulk" stands for tissue thickness, and "Bulk/BW" for unit Bulk, referred to by some companies as "Bulk", or "Specific Volume".
Paper Machine Characterization includes a detailed treatment of the unit operations of paper making, forming, pressing, through drying, creping, and stratification. It contains most of my distilled philosophy. A snapshot of the ideas in the report may be obtained by looking at the graph: Unit Operations .
Furnish Optimization and Other Topics contains, in addition to a treatment of furnish optimization, such concepts as an "absolute handfeel scale" and “Universal Paper Machine” as well. This article and the one above almost complete my philosophically oriented writings on tissue paper. A considerably simpler version, one I suggest to the impatient, is
Furnish Optimization, Simpler Version. To become more familiar with the method and have a hands-on experience with it, please click on the following link which contains a downloadable interactive program: Furnish Optimization Interactive Program.
The article on Stratification describes my method of dealing with the topic, as well as gives results for 2-layer stratification (to reduce file size, it does not contain the data tables). It also demonstrates my technique for normalizing (bringing to common denominator) most tissue properties. It aims a bit too high and has too much information.
The article Strength-Density Relationships in Handsheets is based on the same the same principles. It discusses the rationale for selecting optimum combination of dry strength resins, debonders, refining and wet pressing. While the work is about handsheets, the conclusions have been extended into creped sheets as well.
The article Consumer vs. Diagnostic Properties describes how to define and when to use these two important categories which are often confused. The consumer experiences one type, for understanding the underlying technologies we must use the other.
A related article to the above, more slanted toward graphical treatment, uses my favorite Technology Curves Approach . It describes the best way to determine the property-development capability of paper machines and technologies.
A more precise approach that also includes necessary corrections for Basis Weight to calculate Breaking Length and Bulk/BW is described in Technology Curves with BW corrections.
Softness is one of the most important properties of Tissue and Towel products. I have written several articles about it.
My article Tissue Softness discusses the most important concepts and relationships on this topic, and also indicates some of the best ways to increase it.
A second, related article Softness via Components discusses the components of tissue softness and the best way to measure softness using components.
My most recent article deals with the best way to obtain Handfeel Standards.
I would like to draw your attention to the following excellent website by a colleague of mine: EmbossinTechnologies was founded in 1996 by Carl Ingalls, an embossing specialist. The company provides the technical know-how for embossing, with emphasis on bath tissue, paper towels, napkins, and facial tissue. Expertise includes manufacturing issues and product development.