part two of three part series covers sanitary protection market
By Colin White MCW Technologies Cumbria, U.K.
This is the second in a series of articles on absorbent products. Mr. White discussed the baby diaper and training pant markets in the January issue of Nonwovens Industry; next month’s issue will focus on the adult incontinence market.
The requirement of sanitary napkins and tampons is to provide an effective absorbent structure to receive, absorb and retain menstrual fluid discharges. In the case of panty liners or shields, the requirement is to provide primarily non-menstrual protection aimed at a more general personal hygiene applicational mode.
Products in this group, because of the intimate contact with the user, must be fabricated in such a way to ensure the absence of skin irritants, be discreet in use and provide containment and absorption without leakage in a safe effective way. There is also an important distinction in the mode of use, with sanitary napkins and panty liners worn externally and tampons worn internally.
It is possible to trace the use of menstrual protection products back to at least the second century BC. Early records illustrate that women in Egypt were using a type of tampon made from fine linen about 3500 years ago and Byzantine women were said to use fine Caucasian wool. Cotton products have been known from early times and products based on cotton cloth were use as towels and laundered after use.
Therefore, dating back to early history, we can find reference to the ways in which women adapted the currently available materials to provide a means to manage the menstrual flow. These early references tell of the use of products resembling the internally worn tampons and externally worn towels known today and illustrate that both principles that lie behind the products we know today were known many centuries ago.
Also of interest are early records that show that while vaginal tampons were used in certain areas by women who had an active lifestyle, towels dominated the position because, for the most part, women led a very domesticated lifestyle.
The fact that menstruation is today regarded as a perfectly natural process has by no means always been the case. In the relatively recent past, menstruation was regarded as a taboo subject about which nobody would talk openly.
This undoubtedly led to much misinformation being circulated about the associated effects. Women were expected to withdraw from daily activities, they should not have contact with water and in their presence flowers were claimed to wither and die!
These strange beliefs developed from earlier prejudices that believed that menstruation was something rather strange and mystical because, like the moon, it appeared and disappeared every four weeks in a lunar type cycle.
Fortunately progress in science, wider education and knowledge and development of information systems by the manufacturers of modern-day feminine hygiene products has led to the acceptance of menstruation as a totally natural process, at least in the developed world. However, in emerging world countries, the continuation of some of the strange associated beliefs with respect to this process continues even today.
Although references to tampon-like products occur from very early times, during the course of history the knowledge of these ancient civilization’s practices became “lost.” Thus, the use of a product, which “disappears” into the body and requires an understanding of both female anatomy and physiology, had to be rediscovered and re-learned.
The Menstrual Cycle
This is a hormonally driven process, which is controlled by activity in the brain and ovaries. The first menstruation (menarche) usually occurs about two years after the onset of breast development during the course of puberty.
The onset of the menarche is moving to an earlier and earlier age as girls develop more quickly. It is therefore hard to estimate an “international” age for this to occur, but recent estimates indicate that 13 years is now the “mean.” The end of the menstrual cycle period, known as menopause, is considered to occur at an average age of 50 years, but this is also considered to be at best a “guesstimate.”
In the early stages of the development of external products, advances followed the developments in the related field of baby diapers and as experience was gained in one field, it was rapidly incorporated into the other.
One of the most significant developments was in the area of hot melt adhesives. Until these products became available, absorbent product producers (mainly in baby diapers and underpads) were forced to use water based latex adhesives, which required time to dry out and set.
Therefore in this period there was little motivation to attempt to develop products that did not rely on a belt system to hold the pad in place. With hot melts the whole concept of self-adhesive pads became possible.
These products could be held in place by glue lines on the back of the napkin, which fixed the product in position within the normal panty garment. These concepts were further developed and extended into the development of “panty shield” type products, which were not primarily intended for management of the menstruation, but were rather designed to handle small amounts of body exudates at any time. This allowed the products to be much smaller and more discreet while still fulfilling an important need.
Further developments focused on the absorption aspects of the products and different manufacturers experimented with different ways of altering the absorbency characteristics within the structure of the product to facilitate better fluid distribution and use of the absorbent core.
This led the way to much thinner products and from this point onwards the development of feminine hygiene products rather diverged from the developments in diapers, with new ideas being incorporated in the feminine hygiene sector at a much earlier stage.
By the early 1980s manufacturers started to realize that packaging and presentation of the products to targeted market sectors was very important. The market was highly segmented into user age groups and lifestyles with the younger, more active population more receptive to the improved products and packaging.
With sanitary protection products, the absorbed fluid contains a high proportion of non-soluble particles (e.g. coagulated blood), which result in a badly stained surface of the product after use. Psychologically this was an undesirable side effect and the manufacturers were encouraged to try to find a way that would make this side effect practically disappear from the surface.
The major advance in achieving this objective was made by P&G with the connulated film coverstock that it applied to its Always product range. This plastic film based coverstock was produced with truncated (conical section) holes in the film, which allowed passage of the fluid and particles through the holes in one direction, but which effectively prevented their re-emergence back to the surface layer. This was achieved without loss in fluid permeability through the film.
This development was not only significant in providing a solution to the staining problem, but it also allowed the development of the “dry feel” concept. Although other manufacturers have developed alternative systems to that covered by the P&G patents, in marketing terms the Always product range has been an enormous success.
Although the film-based coverstock material has been tried in other applications such as baby diapers, it has not been as well received by the user public. Thus, although there are other products that use this concept, it is in the field of feminine hygiene where it has been really successful.
More recent developments have included the addition of “wings” to the sides of products to facilitate the fixing of the pad in place in the undergarment and to assist in preventing side leakage. We have also seen the introduction of elasticated side strips on napkins, which makes a more body conformable product and has “borrowed” technology gained in the training pants sector.
By the early 1990s the development principles of the basic product forms had been investigated and more recent developments have been more targeted at resolving some of the user requirements that remain.
Developments In External Products. It is possible to gain some insight into the development trends within individual companies by review of the U.S. patents issued to them.
Developments In Internal Protection Systems. Tampons are designed for menstruation. They are composed of a carded fleece of fibers compressed into a pledgelet form. Tampons are internal devices that are either put into position manually (digital tampons) or with the aid of a plastic or cardboard applicator.
Basically tampons are produced from carded cotton or viscose rayon or blends of cotton and rayon fibers of various types, which are mechanically compressed. The compression may result in the formation of grooves on the outer surface, which will influence the way in which the tampon expands in use.
A withdrawal cord is attached to allow the tampon to be removed from the body. In order to prevent fiber linting and to make insertion easier, the absorbent core of the tampon is usually wrapped in a lightweight nonwoven cover.
The main purpose of the tampon is to absorb and retain the menstrual fluid until its absorptive capacity is reached. The tampon works like a sponge. When the tampon capacity is reached it will begin to leak.
Compressed tampons usually have a dry length of about 50mm and a dry diameter of 11-17mm. The expansion of the tampon in use depends on the way its fibers are compressed. There are tampons that are formed by rolling and then compressing absorbent material into a small cylinder. This type normally expands widthways.
Other tampons are produced by the longitudinal and radial compression of a rectangular or square piece of absorbent fleece and this type expands longitudinally. Other production methods produce tampons that have a corolla type expansion.
Digital tampons, which are inserted with the finger, need to stay compact before insertion and the aesthetic appearance before use is an important factor. For digital tampons the main evolution of the product has been in the method of forming the tampon including the formation of external grooves and in the packaging.
For tampons with an applicator, the external appearance of the tampon after expulsion from the applicator is of minor importance and the main focus of improvement has been in the quality, design and size of the applicator system.
There are currently three methods used for the production of tampons:
i) based on a cotton wool roll, with grooves and radial expansion—requires no applicator
ii) formed from a stitched blank of fiber fleece—expands longitudinally
iii) based on two offset blanks of fleece pressed into a tampon shape; the top expands more than the base—requires an applicator.
It can be seen that there has been relatively little development of the product itself. The problems experienced with the incidence of Toxic Shock Syndrome undoubtedly worried this sector of the industry and recovery has taken a long time to begin to be achieved. Recent developments have indicated manufacturers taking a renewed interest in the sector.
There are distinct product choice differences in different geographic locations of markets for sanitary protection devices. For example, within the European market there are marked differences as to the preference between the use of sanitary napkins or tampons for the primary sanitary protection device .
In terms of future developments, on the basis of feedback from user studies it is possible to draw certain conclusions with respect to outstanding user needs.
Many of the fundamental development requirements have already been addressed, but development work continues at a fair pace to tackle the problems outlined above. The positioning and holding in place requirement is a difficult problem to tackle, especially as products become thinner and smaller. It is, however, a necessary requirement if the most recent ideas of the use of panty shield type products on a daily basis is to be a market place success.
In many parts of the world the penetration of disposable feminine hygiene products in relation to the potential market size is low and this represents a real challenge to the producers of these products.
There are significant market differences based on ethnic background, religious beliefs, use of contraception, etc., which makes the development of targeted user products a necessary evil for those producers who would tackle these markets.
In the developed markets the need for product differentiation with real technologically based improvements (such as was achieved by P&G with its Always range represents the only sure way of gaining market share in an already saturated market.
It can be seen from the developments to date that this sector of the hygiene products business tends to be more innovative in its approach to new concepts and new ways of achieving its objectives.
Already the patent literature shows the search for new routes to solving old problems (see U.S. Patents 5,505,720 McNeil-PPC “Melt Blown Menstrual Pad” and 5,387,207 Procter & Gamble “Thin-unit-wet absorbent foam materials for aqueous body fluids and process for making same” for example) and this must augur well for the future.
(Note: In this product sector there are literally hundreds of U.S. patents and these are increasing at an exponential rate. In this paper patents are selected simply to illustrate the concepts involved and this does not mean that there are not other patents, assigned to other companies, that invalidate or supersede those examples quoted.)