MEMO PAPER®: the experience of converting at the service of papermaking

The over 800 patents filed bearing his name testify as to how Engineer Memo Bagiotti has been one of the main protagonists in the development of tissue converting machine technology.

With his over 34 years of experience in the design of tissue converting machines for Fabio Perini S.p.A., leader in the field, today Mr. Biagiotti, having retired as Technical Director of the company, has put his vast experience to the use of papermaking by filing patents in this field, as well. As often happens when well-known technology is transported to a different field from that into which it was born, the idea presented in the pages that follow seems to have all the features for success, and the agreement with A.Celli Paper S.p.A. seems to create the ideal conditions.


Memo Biagiotti

According to this idea, paper can be formed by a process known in the art and, then, transferred to the drying section by means of basically known elements such as wires and felts.

Before entering the drying section, the formed paper has to be brought to a dry content in the order of 40-45% or more by using means like pressure, vacuum, heating or other.

Then the paper is removed from its support and is passed through the nip formed by a couple of embossing rollers engraved with a very particular pattern.

After embossing, the wet embossed paper is passed through a drying unit which can be any known system and the water content is lowered down to a level at which the paper is completely dried.

The drying of paper after embossing makes it able to maintain deformation in a very stable way (like ironing a shirt after applying starch on it) and to create in the web a kind of “memory”, from which the brand “MEMO PAPER”, which has been filed to protect the name of the product obtained through the patented process.

In other words, the web structure according to this new process presents millions of paper springs which make it return to its initial condition when it is put under tension and then released.

The paper can then either be directly wound in reels (Patent – Fig. 1A) or can be wound after submitting it to a calendering process which improves the quality of its surface (Patent - Fig. 1B).



The advantages expected from this invention are listed below:


1. Increase in web calliper.

2. Reduction in fiber consumption to create the web.

3. Reduction in power required to complete the drying of the web.

4. Increase of machine production speed considering the same quantity of pulp-and-water mixture at the headbox.

5. Consistency in quality of paper in time

6. Elimination of risk of fire due to blade change and blade-yankee contact

7. Reduction in paper dust generation during converting

8. Increase in capability of water absorbency

9. Structured aspect of the web.



Lab-created webs demonstrate that the increase in calliper can easily be in the order of 50-80% if we calender the dried web, while it can reach values of more than 3 times that of a standard web if we do not calender it.



Supposing a calliper increase in the order of 50%, we can make a mathematical calculation to demonstrate that the same calliper can be obtained with 50% less fiber: of course by reducing the quantity of fiber, the capability of maintaining the embossing is also reduced, but even if we can keep half this reduction, it means 25% less fibers.



The possibility of making similar paper by using 25% less fibers also translates into 25% less energy to dry it.

We must consider that additional savings can be obtained because initial water removal can be performed by calendering the web and again by the fact that reeling is obtained at a speed which is higher than the formation speed (the opposite of a conventional machine).


4. INCREASE OF MACHINE PRODUCTION SPEED. It is well known by people with expertise in the field that the process of embossing paper generates an elongation in it. This means that the embossing unit runs at least at the same speed as the headbox and the paper leaving the embossing rollers can be kept under tension (very low tension) only by making the subsequent drying system move at a higher speed.

Due to this characteristic, the paper machine shows an increase of production at least equal to the non-needed difference in speed between the yankee and the Pope reel normally used when paper is detached from the drier by means of a creping blade.

This means also that the machine at the headbox has to deliver a pulp quantity that exceeds the value of the final paper grammage.


5. CONSISTENCY OF PAPER QUALITY IN TIME. The creping impressed in the paper by the embossing rollers does not generate any wear on the rollers themselves (as happens in contact between blade and yankee) for a very long time, giving the paper very stable characteristics.


6. ELIMINATION OF RISK OF FIRE DUE TO BLADE CHANGE. Even if they are both made of steel, there is no contact between the two rollers, so there is no possibility of sparks starting fire, as happens very often in standard machines when the static blade is pressed against the rotating warm yankee roller.


7. REDUCTION IN PAPER DUST GENERATION DURING CONVERTING. The pressure exerted on the water and pulp solution to remove water also creates a stronger connection between wet fibers than in conventional machines; these are only partially broken by the process of embossing. For this reason, it is feasible that dust generation during converting paper produced according to this process is lower than with conventional paper.


8. WATER ABSORBENCY. The web so formed has a real surface very much extended with respect to a conventional one, so it has more water-to-paper contact to allow more absorbency.



The disadvantages expected from this invention are listed below:


1. Handfeel of the web produced with this process is not as smooth as a conventional web.

2. Limited value of elongation in the web.

3. Embossing at 2000 m/min has never been experienced.


1. HANDFEEL. Handfeel of a web produced according to the patented process is less smooth than the feeling when touching a standard web.

The difference can be limited by choosing the right mix of fibers and, at process completion, by passing the web trough the nip formed between at least two calender rollers.

This process can be considered compulsory in order to reduce the thickness of the web obtained by the embossing to industrially acceptable values. A further improvement on the web’s handfeel can be obtained by adding softening lotions to the finished web during converting. The combination of these processes produces a web which can easily be confused with a TAD web in a blind test.


2. LIMITED VALUE OF ELONGATION. This can be properly considered more a difference then a disadvantage.

The stretching level obtained by the patented process is generally lower then the level used in standard webs, but it is still in a range that makes it possible to easily convert the web. In fact, the values registered make it possible to emboss the web, even heavily, and to control the tension between different operating machines in a converting line.


3. EMBOSSING AT 2000 M/MIN. This speed has never been experienced in embossing technology during converting, but some considerations have to be made:

The embossing disclosed in the patent is different from any kind of embossing currently used for what concerns the pattern. There is no rewinder that can run at such a high speed and, by consequence, there has been no need for it so far. Nevertheless there is evidence of embossing at speeds near 1000 m/min and technical considerations do not make embossing at 2000 m/min impossible.


EXPERIENCES. The experiences on which the above considerations are based have been carried out in the laboratory of the Paper Department of Karlstad University in Sweden, which is very well equipped to study paper problems. There is laboratory equipment to prepare the pulp-and-water mixture with fibers refined to a controlled level and equipment to define the dilution to obtain the desired paper grammage. They also have a machine which can produce sheets of paper at a speed of 600 m/min and a calender which can be used either to reduce water content in the web or to calander it at the end of the process to smoothen it.

In this lab there is also a large heated roller to dry the previously prepared sheet, simulating the effect of the Yankee drier on the paper, not to mention ovens, precision weighing devices, etc.

The only equipment they did not have to simulate the process disclosed in the patent was a small embossing unit to emboss the still wet web, but this was fulfilled by preparing a dedicated in-scale unit, with the characteristics needed for the true embossing unit.

This was equipped with two different embossing patterns to evaluate the influence of this process in the finished web.Tests were done in following steps:


1. Create the web of the desired grammage removing a first quantity of water directly with the formation machine.

2. Press the dewatered web between calender rolls to further reduce the water content.

3. Emboss the web.

4. Dry the embossed web.

5. Calender the finished web.


Three different series of tests were done with different parameters in the paper and in the process and the results found by analyzing the webs produced confirm that the patented process allows to:


• Reduce drying power consumption by 25-30%,

• Reduce fiber consumption by 15-25%,

• Increase calliper of the web by 25-50% at the end of the process.


The rest of characteristics can only be verified by real tests.


PATENT AGREEMENT WITH A.CELLI PAPER. After the first presentation, A.Celli Paper S.p.A. was very interested in this idea because they saw in it the possibility of introducing in the industry a new process to make a web of paper capable of competing with TAD without the negative aspect of power consumption.

Indeed, if we consider the main characteristics of the new web, we see a very high calliper and an evident texture imprinted by the embosser.

After reaching an agreement on the rights of the patents, we started working together in the development of the process called ITAD to produce the special paper called MEMO PAPER®.

The next step was to find a real paper machine to modify in order to produce MEMO PAPER® on a real industrial scale to compare data obtained from an actual process with lab results.

Thanks to the fruitful collaboration with A.Celli Paper S.p.A., the phase described above has been completed and has yielded very interesting results, as we will illustrate in a subsequent article.


Eng. Memo Biagiotti can be contacted at: guglielmo.biagiotti@alice.it

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