Research & Innovation
Clothing physiological research
in the service of wear comfort
Clothing physiological research in the service of wear comfort
PUBLISHER:
Hohenstein Institute
Schloss Hohenstein
74357 Boennigheim
GERMANY
CONTACT:
Dr. Andreas Schmidt
Tel.: +49 7143 271 0
Fax: +49 7143 271 94199
E-Mail: [email protected]
Website: www.hohenstein.de
Tel.: +49 7143 271 717
Fax: +49 7143 271 941717
E-Mail: [email protected]
HOHENSTEIN
Head of the Department
Function and Care
© 2009 Hohenstein Institute
2
Preface
Prof. Dr. Stefan Mecheels
Head of the Hohenstein Institute
Man has always been interested in the relationship between clothing and physical well-being.
The scientific discipline of clothing physiology, on the other hand, which has been and continues
to be shaped primarily by the Hohenstein Institute in Germany since 1946, is comparatively
young.
In this special publication, we have summarized the milestones of a development that ranges
from the first form of human clothing made from hide and leather through to modern functional
textiles. Using the research methods of clothing physiology, items of clothing, as well as bedding
and sleeping bags can now be optimally tailored to their respective area of application.
The innovative strengths of the scientists at Hohenstein formed the foundation for this.
Clothing physiological research owes its pioneering and now internationally recognized test
systems such as the Hohenstein Skin Model and the articulated thermal manikin, “Charlie”,
to their work.
On 1 October 2009, the Hohenstein Institute have bundled its professional competencies in
the current company segments Clothing Physiology and Textile Services & Innovations into a
new department by the name of „Function and Care“. The department will be managed by Dr.
Andreas Schmidt who will be succeeding Prof. Dr. Karl-Heinz Umbach, who has retired from
the operational business after 33 years of occupation for the Hohenstein Institute.
With pride, we look back on 60 years of work in the service of wear comfort and look forward
to continuing to be actively involved in creating future generations of innovative textiles.
Prof. Dr. Stefan Mecheels
Head of the Hohenstein Institute
3
Clothing physiological research in the service of wear comfort
Topics
Clothing for the „naked ape“
6
Clothing and mysticism
7
The birth of qualitative clothing physiology
8
The dawn of a new age in the textile industry
8
Expertise made in Hohenstein
9
The birth of quantitative clothing physiology
11
The measure of all things
12
The overwhelming success of synthetic fibres
13
Wear comfort is ess-sense-tial
14
High marks for comfort
15
As you make your bed...
4
16
Freezing in a sleeping bag?
17
Comfort mobilises
18
Children are more than just small humans
19
The battle against cold hands and perspiring feet
20
Clothing physiological measurement methods at a glance
21
Clothing physiological research at the Hohenstein
Institute in the service of wear comfort
Ever since its foundation in 1946, one of the main
focuses of research at the international textile
research and service centre at the Hohenstein
Institute in Bönnigheim has been the interaction
between textiles and human physiology. The
objective was and remains the development of
clothing, bedding and vehicle seats which optimally
support temperature regulation depending on
the environmental climate and activity, in other
words, offer a high level of comfort. As the feel of
the textiles against the skin, i.e. the skin sensory
properties, and the fit (ergonomic wear comfort)
are crucial factors in determining whether a textile
product is perceived to be pleasant, these factors
must also be taken into consideration at the
product development stage.
The founder of the institute, Prof. Dr.-Ing. Otto
Mecheels, his son and successor as head of the
institute, Prof. Dr. Jürgen Mecheels, together
with the present deputy head of the Hohenstein
Institute for Clothing Physiology, Prof. Dr. KarlHeinz Umbach, are regarded as the fathers of
research into clothing physiology in Germany,
and thus as pioneers for functional textiles in
their current form.
Thanks to the Skin Model and “Charlie”, the
articulated thermal manikin (figure 1), and special
skin-sensory equipment developed by the
Hohenstein specialists, the discipline of clothing
physiology now has a range of clothing-specific
parameters which enable wear comfort to be
evaluated objectively. This made it possible for
Figure 1: Using “Charlie”, the
human thermoregulation
model, the wear comfort
of clothing can now be
objectively assessed and
optimised.
5
Clothing physiological research in the service of wear comfort
Figure 3:
The thermophysiological and
skin-sensory properties of
clothing, such as that worn
by the iceman, “Oetzi”, in the
Neolithic period, can also be
determined using clothing
physiological methods.
the first time in the long history of clothing to
evaluate and optimise wear comfort specifically
in relation to defined areas of application and
requirements. Previously, the choice of materials
and patterns was influenced to a large extent
by mystical beliefs that were closely linked to
cultural development.
Figure 2: Up until modern
times, humans only protected
themselves against the
effects of weather with
clothing made from natural
materials such as wool,
leather and hide.
6
Clothing for the “naked ape”
Loss of body hair represents a milestone in
human evolutionary history. Like all mammals, the
first primates regulated their body temperature
through respiration, which significantly restricts
the amount of heat dissipation.
Early man used his entire body to dissipate heat,
however, and was therefore superior to the
majority of animals in terms of endurance and
adaptability.
Moreover, it was only when he had acquired the
ability to sweat that the “naked ape” gained
the ability to communicate using language
even when it was extremely hot or during
strenuous exertion. The ability to sweat is only
really effective however if there is no body hair
to restrict the circulation of air. During the course
of evolution, man therefore lost the majority of
his body hair.
The colonisation of colder areas of the world
was consequently only possible for early man
with the invention of protective clothing (figure
2). But even under climatic conditions that do
not require the body to be protected by clothing,
typical forms of clothing developed as part of
man’s cultural development on ethical-religious
grounds (figure 3).
Figure 4:
Drawings in Egyptian tombs
show the special importance
attributed to cult garments
made of linen.
Clothing and mysticism
The use of natural materials such as hide, wool,
cotton and linen have always had mystical, as well
as practical associations.
In Egyptian civilization, linen fabrics, for example,
were regarded as particularly “pure”, and were
therefore the preferred choice for cult purposes
(figure 4). Sheep’s wool, on the other hand, was
regarded as “impure” and only used for clothing
for the lower levels of society. Similarly, woollen
clothing could not be used for burial in order not
to jeopardise the passage to the realm of the
dead.
The first reflections on the function of clothing
were made by the Greek philosopher Empedocles
around 500 B.C. He put forward the theory that the
skin “breathes”. Clothing should not prevent the
perspiration that occurs as a result of “cutaneous
respiration”, and should also help to avoid toxins
penetrating from the environment. Linen fabrics
were said to best fulfil these requirements. The
concept of “cutaneous respiration” and the
resulting rejection of woollen and cotton clothing
by the higher social classes continued until the
baroque period. Nobility and the upper clergy
dressed in linen and silk.
A paradigm shift occurred around 1650:
Santorius, a physician from Padua, put forward
the theory that serious diseases could be avoided
by stimulating perspiration from the body by
means of particularly warm clothing. Against the
background of the devastating plague epidemics,
which had depopulated entire areas in Europe
since the middle ages, he recommended wearing
as many layers of woollen clothing as possible.
He ascribed its warming effect to the residual
“inner warmth” of the sheep.
Based on the ability of wool to absorb large
quantities of moisture, toxic vapours from the
surrounding air were also believed to be absorbed
by the wool. It was also thought that pores were
opened as the wool rubbed against the skin, thus
stimulating “cutaneous respiration”.
The extent to which the belief in the superiority of
wool over linen and cotton became established
amongst the population compared with former
convictions is demonstrated, amongst other
things, by the English Wool Act.
After this, between 1678 and 1824, the dead
could only be buried clothed in sheep’s wool,
as this was believed to protect the living from
the toxins released from the decomposing
bodies.
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Clothing physiological research in the service of wear comfort
The birth of qualitative clothing
physiology
Doctors carried out systematic wear tests on
clothing for the first time in the 18th century. They
held fast to the concept of cutaneous respiration,
but also put forward a counter theory to Santorius,
recommending that people wear textiles that were
as light as possible with an open cell structure, in
order to facilitate cutaneous respiration as far as
possible. They regarded excessive perspiration
as a result of clothing that was too warm as being
responsible for diseases and as being detrimental
to the organism as a whole. In a new paradigm
shift, linen and cotton were once again portrayed
as being superior to wool.
With the discovery of oxygen and its connection
to human respiration, the concept of “cutaneous
respiration” as a central factor was called into
question for the first time. In wear tests, on the
other hand, the first aspects of wear comfort as
we define it today were investigated: thermal
insulation, the capacity to absorb moisture and
the limit from which the material is perceived by
the wearer as being wet.
Between 1907 and 1920, the first systematic
research into the connections between the
physiology of the body and clothing was carried
out, and the results of this still apply in principle
today:
•
The effect of “cutaneous respiration” is
negligible.
•
Thermal insulation does not depend on the
fibres used, but on the construction (i.e. on
the thickness, weave, porosity, airtightness
of the textiles).
•
Wickability is particularly important for the
perceived wear comfort.
•
Even with respect to wickability, it is not the
fibre material itself which is important so
much as the construction parameters.
•
There are advantages and disadvantages to
all fibre materials, depending on the specific
wear situation.
The dawn of a new age in the textile
industry
The development of the first synthetic textile
fibres, “Nylon” (1935 by Dr. Wallace Hume
Carothers in the USA) and “Perlon” (by the
German chemist Prof. Dr. Paul Schlack in Berlin
in 1938), represented the dawn of a new age in
the textile industry: in addition to the traditional
natural fibres, new materials were available for
the first time whose properties could also be
specifically influenced (figure 5).
Against the background of the 2nd world war,
physicists, chemists, textile engineers and
doctors, in particular in the USA, worked on the
Figure 5: Synthetic fibres became available for garment
manufacturing for the first time in the 1930s with Nylon and
Perlon
8
optimisation of clothing for the troops. For this,
they investigated the interaction between body,
climate and clothing using scientific methods.
In doing so, they recognised for example the
importance of design for the physiological
function of clothing.
Figure 6: As there was no
climatic chamber, wear tests
were still carried out on a test
track in the vineyards around
Hohenstein in 1953.
Expertise made in Hohenstein
Following the 2nd world war, Prof. Dr.-Ing. Otto
Mecheels was the first scientist in Germany
to become involved in this field in his newly
established Hohenstein Research Institute in
Bönnigheim. It quickly became clear however
that it was not possible to carry out an objective,
scientifically based evaluation of comfort
using wear tests on people alone (figure 6).
Deviations in the results due to fluctuations in
the environmental temperature, factors related to
individuals etc. therefore needed to be eliminated
using laboratory equipment, which simulated the
physiological processes in the body as realistically
as possible, but under controlled conditions which
could be reproduced at all times.
The first thermoregulatory transport model of the
human skin (referred to as the Skin Model for
short) to measure heat and moisture properties
was developed by Prof. Dr. Jürgen Mecheels, son
of Prof. Dr.-Ing. Otto Mecheels, in 1956 (figure
7). This marked the starting point of quantitative
clothing physiology.
However, with this first prototype of the Skin
Model, unlike today, it was not possible to
record the heat and moisture transport through
the textiles separately, so the “breathability”
could not yet be measured in physically defined
terms.
To record the interaction between body-climateclothing in quantitative terms, further measuring
devices were therefore required. Under the
aegis of Prof. Dr. Jürgen Mecheels, the first
human thermoregulation model in Germany was
developed.
From 1968 onwards, measurements using
“Charlie 1” were used to complement clothing
physiological parameters recorded to determine
objective wear comfort (figures 8, 9, 10).
Whereas it was only possible to test the textiles
in the form of fabric layers using the Hohenstein
Skin Model, measurements using “Charlie 1”
were carried out on ready-made garments.
Figure 7: Prof. Dr. Jürgen
Mecheels developed the
precursor to the Hohenstein
Skin Model as part of his
dissertation in 1956.
Figure 8: Prof. Dr. Jürgen
Mecheels’ colleagues proudly
demonstrate the “only
clothing robot in the world”
in 1968 (press text). “Charlie
1” still has to manage without
a head, hands and feet.
From left: Dipl. Ing. Luthard,
Siegfried Müller, Dr. Roland
Schmieder, Renate Demeler,
Franz Raab.
Figure 9: In 1974, “Charlie 1”
appears with three models
on the 25th anniversary of
the Hohenstein Technical
Academy [Lehranstalt
Hohenstein e.V.]
9
Clothing physiological research in the service of wear comfort
Figure 12: Since 1962, a
climatic chamber has been
available at the Hohenstein
Institute for wear tests.
This allows a wide variety
of weather conditions to be
simulated.
10
Figure 10: The body of “Charlie 1” consists of copper, which
is painted black in order to simulate the thermal radiation
behaviour of the human body as closely as possible.
Figure 11: Optimising the physiological function of clothing
is particularly important in relation to situations involving
extreme physical exertion, such as soldiers in battle.
“Charlie 1” was the first articulated thermal
manikin in the world to perform a walking action.
As the design and ventilation effects associated
with movement have a considerable influence
on the physiological function, this meant that
reliable, practical conclusions relating to items
of clothing or clothing systems could be drawn
for the first time. The thermal insulation of the
items of clothing tested results from the amount
of energy that needs to be transferred to the
body of “Charlie 1” in order to keep his “skin
temperature” constant at given values.
The birth of quantitative clothing
physiology
In order to be able to translate the data obtained
using the Skin Model and articulated thermal
manikin into the comfort perceived by man, Prof.
Dr. Jürgen Mecheels and his colleagues carried
out numerous wear tests on human subjects.
Within research projects at the Hohenstein
Institute for Clothing Physiology, which was
founded in 1961, tests were carried out on a
wide variety of materials and a range of climatic
conditions and physical activity levels. Since
1962, a climatic chamber has been available in
Hohenstein for this purpose, where a wide range
of temperature and weather conditions can be
simulated (figures 11, 12).
In order to make it possible to translate to humans
the data obtained using “Charlie 1” and his
successor, the technically improved “Charlie
2” (figure 13), developed at the beginning of the
1970s, a so-called “standard man” (1.73 m, 70
kg) and “standard woman” (1.60 m, 60 kg) were
defined. These are still used today with regard
to body weight as a measure for the selection of
suitable test subjects and as general reference
values when presenting and interpreting clothing
physiological data.
Figure 13: At an experimental demonstration of
the articulated thermal manikin, “Charlie 2”, the
left leg was submerged in iced water and its
“thermoregulation” readings were recorded.
The physicist Prof. Dr. Karl-Heinz Umbach (figure
14) significantly improved and extended the
measuring methods used in clothing physiology
as well as biophysical evaluation models from
1976 onwards. One of his first projects was the
further development of the Hohenstein Skin
Model. Using a porous sintered metal plate as a
measuring surface, water vapour and fluid water
were released in a controlled manner in a climatic
chamber, thus simulating perspiration of human
skin and different wear situations with different
levels of sweat production. Moisture sensors
between the measuring surface and the textile to
be tested measure the buffer effect of the textile
and how much water vapour can be transported
from the body within a specific time. This modern
measuring technique supplies more accurate
and more detailed results. While the manual
evaluation of the measuring data from a series
of wear tests could previously take up to three
months, computers were now able to complete
this in just a few hours (figure 15).
With “Charlie 3” (post 1980), the bodyheat was
no longer supplied using hot water, as with his
predecessors, but using electric cables in the
body. Its surface temperature was also controlled
separately for the first time for 16 individual body
segments. This took into account the fact that
Figure 14: From 1976, Prof. Dr. Karl-Heinz Umbach (right)
further developed the clothing physiological measuring
methods developed by Prof. Dr. Jürgen Mecheels (left)
and took over as head of this department in Hohenstein.
Figure 15: Due to the complexity of the measuring
results and the ever increasing amount of data
involved, the Department of Clothing Physiology
required its own computer centre at the beginning
of the 1980s.
11
Clothing physiological research in the service of wear comfort
the temperature distribution on the human body
varies considerably. In order to feel comfortable,
this should be at around 30 ºC on the head and
around 34 ºC on the trunk. The skin temperature
should be around 32 ºC on the forearm, on the
other hand. In order to offer optimum wear
comfort, the thermal insulation of a garment
should be segmented accordingly.
Today, the fourth generation “Charlie” (figure 16)
is in operation at Hohenstein and demonstrates
an even higher degree of measuring accuracy
than his predecessors due to the separation of
the individual measuring segments using Teflon
plates or strips, which makes it possible to
separate the heat flow into the individual sections
of the body.
But even the now technically superseded
“Charlie 2” is still used in special circumstances
such as the optimisation of marine survival suits –
its electrically-heated successors could short
when swimming in ice-cold water.
In 1986, scientists at Hohenstein developed
a “brother” for “Charlie 4” which was named
Ralphie and sold to an American test and research
institute, where he is still active today.
Figure 16: As with his direct
predecessor, the “skin
temperatures” of the latest
“Charlie 4” are also controlled
in 16 sections and the
respective heat flow through
clothing are messured – it is
therefore possible to make
differentiated statements on
the thermal insulation and
physiological function of a
garment.
12
The measure of all things
Measurements using the Hohenstein Skin Model
(figure 17) and the articulated thermal manikins,
“Charlie 2-4”, (figure 16) now form standard tests
in the field of clothing physiology worldwide.
In Germany, Standard DIN 54101 has defined
the measuring method using the Hohenstein Skin
Model since 1991. This was replaced in 1993 by
the international standards ISO 11092 and EN
31092. Today, the thermal insulation and relevant
water vapour resistance (breathability) of a textile
are not only measured in “normal” situations
using the Skin Model to evaluate wear comfort;
the buffering and transport capacity of vaporous
and liquid sweat of the textiles during fairly heavy
or extremely heavy sweating are also measured.
Thanks to the fundamental research work by
the Hohenstein Institute for Clothing Physiology,
specification values for these parameters are
known. Textiles must satisfy these values in order
to effect good wear comfort, depending on the
conditions under which they are used.
In 1988, these clothing physiological specification
values were incorporated in standards for
protective clothing for the first time. DIN 61539,
“Weatherproof clothing” was adopted, which
was innovative in taking into account the clothing
physiological demands of the wearers in the
form of minimum “breathability” in addition to
technological requirements of textiles for this
type of clothing, such as impermeability to
water, tear resistance etc. In 1998, this German
standard was replaced by the European EN 343.
As a result, since this time, specification values
for wear comfort have been included in numerous
other standards for protective clothing, e.g. in
DIN 10524 for Workwear in the food industry, EN
469 for Protective clothing for fire fighters and EN
471 for High-visibility warning clothing etc.
The overwhelming success of synthetic
fibres
Nyltest shirts with their extremely poor wear
comfort gave synthetic fibres a bad image in the
1960s and subsequent years. Tests by Prof. Dr.
Karl-Heinz Umbach proved however that with
appropriate construction, also textiles made of
synthetic fibres could not only enable heat and
moisture management on the skin comparable to
that of natural fibres, but could also offer superior
results under many circumstances.
On the basis of the research results from
Hohenstein, the first doubleface textiles were
developed at the beginning of the 1980s, whereby
synthetic and natural fibres were combined with
one another as two distinct layers.
In 1980, an Austrian sports underwear
manufacturer kitted out the national women’s
team for the Winter Olympics in Lake Placid with
the world’s first doubleface underwear, which
was developed in conjunction with scientists at
Hohenstein. The synthetic fibres lying against the
skin transport perspiration quickly and effectively
away from the body, while the outer cotton
ensures a good buffering effect and evaporation
of the moisture.
Combined in this way, these two materials offer
significantly improved wear comfort over cotton
underwear, which was used previously, thanks to
improved sweat transport which results in a drier
feeling against the body and the more rapid drying
of the material. Following the positive response
of the Olympic athletes, the “Transtex” double
Figure 17:There are now
seven Hohenstein Skin
Models in Hohenstein’s
own laboratories, and 16
more devices manufactured
by Hohenstein in service
worldwide.
13
Clothing physiological research in the service of wear comfort
face underwear was launched on the market for
amateur athletes, too (figure 18). Its resounding
success on the market marked the beginning
of a period of popularity for functional textiles
which is still continuing today, and which has
led to ever increasing differentiation based on
the intended use of the materials.
Figure 18: The doubleface
underwear for the Austrian
women’s team at the Winter
Olympic Games in 1980 in Lake
Placid is now regarded as
the first example of modern
functional underwear.
Source: Löffler
Skin
Polypropylene
Cotton
Wear comfort i s es-sense-tial
In the early years of research into clothing
physiology at the Hohenstein Institute, the skin
sensory aspects of textiles, in other words the
sensation of the textile against the skin, proved
elusive. Back in the 1950s, its evaluation was
already included in the scope of the survey with
human test subjects, but with the same problems
in terms of objectivity and reproducibility as with
the thermophysiological evaluation.
Figure 19: Using a range
of measuring methods,
including determining the
surface index, as shown
here, skin sensory aspects
of textiles are recorded
and incorporated into wear
comfort ratings as part of the
physiological testing at the
Hohenstein Institute
14
In the early 1970s, Sueo Kawabata from the
University of Shiga Prefecture in the Japanese
Hikone City was one of those who worked on
devices that simulate the human sensation of
touch. Using these, the subjective sense of touch,
known as the “textile hand”, can be translated
into exact physical parameters. Measurement of
the shear stiffness has been shown to correlate
extremely well with the subjective evaluation
of fabric hand. When determining the shear
stiffness, the force required to produce a parallel
movement in a horizontally fixed textile strip is
measured.
As the sensation on the hands is significantly
different to that on the body, the Japanese
research results cannot be used as they stand
to assess the “skin sensory wear comfort” of
textiles. At the Hohenstein Institute, Prof. Dr.
Karl-Heinz Umbach and his colleagues therefore
analysed the influencing variables for the skin
sensory perception and developed a new
measuring and evaluation process: clothing
which clings to skin which is wet with sweat, for
example, is perceived as extremely unpleasant.
Textiles worn close to the skin must therefore not
“cling” to the skin surface as far as is possible.
Napped textile surfaces and protruding fibre ends
form natural spacers between the textile and the
skin. Using several series of tests, the team of
Hohenstein specialists defined a surface index
using an image analysis system that expresses
Figure 20: Using the continual
contact angle measurement
of a drop of water on the
textile surface, it is possible
to calculate how fast the
material absorbs liquid sweat
the number and length of these spacers as a
numerical value (figure 19). The value of this
surface index must lie between 3 and 15 in order
to effect good skin sensory wear comfort.
Using modern image editing on the computer, the
number of contact points between the textile and
the skin was measured. This shows whether the
textile is perceived to be unpleasantly cold and
damp or wet when perspiring.
In order to evaluate the effects which arise when
the textiles rub against the skin when moving, Prof.
Dr. Karl-Heinz Umbach developed a measuring
device whereby the textile material to be tested
is drawn in a controlled manner over a sintered
glass plate which releases water from its pores as
a skin simulator. An wet cling index is determined
from the force required for this. The numerical
value indicates whether the textile clings to the
skin during perspiration.
The stiffness of the textile is measured as another
influencing variable affecting skin sensory wear
comfort. For this, the bending angle of a strip
of fabric placed on a thin bar is determined in a
measuring device using a laser beam. Here, too,
the decades of experience of the Hohenstein
scientists help to define specifications for various
product ranges and fields of application that are
used to help prevent mechanical skin irritation
due to the excessive bending rigidity of the
material.
As damp skin is more easily irritated mechanically
than dry skin, it is also important that clothing
worn close to the skin can transport fairly large
quantities of sweat rapidly to layers further from
the skin. The sorption index indicates how quickly
a textile material is able to absorb liquid sweat and
transport it away from the body. To determine
this, Prof. Dr. Karl-Heinz Umbach developed a
special video-based, continual contact angle
measurement for a drop of water that is placed
in a defined way on the textile surface (figure 20).
This makes it possible to accurately determine
how long it takes for the water to totally penetrate
into the material.
High marks for wear comfort
Thanks to the laboratory tests developed, a wide
range of key textile data has been available at
the Hohenstein Institute since the middle of the
1980s for the evaluation of the wear comfort of
textile fabrics. From this, it has been possible for
specialists to evaluate individual aspects such
as the “breathability” of a material and provide
construction guidelines for their optimisation.
Prof. Dr. Karl-Heinz Umbach’s aim is subsequently
to combine the individual parameters to make an
overall statement regarding the wear comfort of
a textile. This wear comfort rating ranges from
1 (= excellent) to 6 (= inadequate) following the
German school grading system, and provides
a quantitative assessment of the physiological
quality of a textile product, as well as making it
possible for those who know little about textiles
to make direct product comparisons based on
wear comfort when making a purchase.
15
Clothing physiological research in the service of wear comfort
The combined experience of the Hohenstein
specialists over a number of decades is utilised
in particular when developing the different
mathematical formulae that provide the wear
comfort rating. These formulae differentiate the
type of clothing and the wearer’s
level of activity and are based on
the textile parameters measured
using the Skin Model and skin
sensory devices.
Since 2003, manufacturers and
retailers have also been able
to advertise the wear comfort
rating on the product itself,
e.g. as a hang tag or printed
onto the packaging (figure
:
FOR
ESTED
T
E
L
21) using the Hohenstein
OTE
SAMP
ORT V
COMF
Quality Label.
WEAR
In conjunction with other
Figure 21: The
parameters tested, such
Hohenstein Quality
as freedom from harmful
Label for the “Wear
OOD)
G
substances or the use
Y
R
Comfort Vote”
(VE
X
X
of nanotechnology,
X
X
to document the
9.4.
.: FI 0
O
N
T
objective and farphysiological quality
TES
of clothing at the Point
reaching
quality
of Sale.
statements can be made for a product
and communicated to consumers.
1.2
As you make your bed…
It is not only those around the world who wear
clothing who benefit from the findings of the
Hohenstein Institute in the field of clothing
physiology – anyone who uses bed linen,
encasings (for those allergic to house dust mites)
Figure 22: During the night,
bed components must
transport around ¼ litre
of sweat away from the
body of the sleeper while at
the same time keeping the
“microclimate in the sleeping
pocket” stable within a range
perceived to be comfortable –
even when the environmental
temperature varies.
16
heat transfer
moisture transfer
buffer effect
heat
production
and duvets also benefits from improved sleep
comfort.
When evaluating the sleep comfort of duvets, the
focus is on the temperature balance of the human
body in relation to the environmental temperature
and the heat and moisture management within
the “sleeping pocket” (figure 22).
A physiological sleep comfort rating ranging from
1 (= excellent) to 4 (= unsatisfactory) can be
calculated for duvets. Similar to the wear comfort
rating for clothing, this makes a statement on the
ability of the product to maintain a pleasant body
temperature when in bed or asleep, and to quickly
and effectively transport any sweat away from
the body. The thermal insulating effect of a duvet
plays a particularly important role in temperature
management. The guiding principle of earlier years,
“the thicker and heavier the duvet, the better the
level of thermal insulation”, has been disproved
by tests at Hohenstein (figure 23). In contrast,
the objective of research in this field today when
developing a modern duvet is to achieve thermal
insulation suited to the individual’s needs with a
duvet that is as lightweight as possible.
In order to simplify guidance for retailers and
consumers, the scientists at Hohenstein defined
three thermal insulation classes for duvets in
1999 based on their tests. Using a graph
displayed in specialist bed retailers (figure 24),
the customer can identify the most appropriate
thermal insulation class based on the nighttime
temperature in his bedroom and his personal body
weight. This is higher, the lower the environmental
temperature and body weight of the sleeper.
Whereas someone weighing 50 kg generates
body heat of only 62 Watts, someone weighing
110 kg would generate 101 Watts. As both
individuals require the same skin temperature
to feel comfortable and maintain body functions
during sleep, the thermal insulation of the duvet
must be significantly higher for the individual with
a lower body weight. The Hohenstein Quality
Label also provides information on the thermal
insulation class of a duvet (figure 25).
Naturally, a duvet does not only have to have
optimal thermal insulation, it also needs to be able
to effectively transport excess sweat away from
the body of the sleeper. This is expressed in the
sleep comfort rating that is determined using a
prediction model developed at Hohenstein from
measurements using the Skin Model and the
articulated manikin, “Charlie 3”.
Two sleep comfort ratings for duvets are stated
on the Hohenstein Quality Label, one for warm
and one for cold environments (figure 25). The
crucial factor for deciding whether the rating for
a warm or a cold environment needs to be taken
into consideration when purchasing a product is
the room temperature during the period in which
the product will be used (summer, winter, all-year
round) and the individual weight of the buyer. The
graph shown in figure 24, which is displayed in
specialist retailers, once again helps in making
the correct choice. For example, for an individual
weighing 80 kg with a bedroom temperature
above 18°C throughout the year, the rating for a
warm environment is key. If the temperature is
below this throughout the year, the rating for a
cold environment should be taken into account
when selecting a product. If an “all-year duvet” is
required for extremely varied room temperatures,
both ratings must be taken into consideration.
When purchasing a sleeping bag, the most
important factor is the minimum environmental
temperature at which this can be used without
feeling cold. “Charlie 3” provides the answer
to this question, too. He is used to measure the
effective thermal insulation of the sleeping bag for
the sleeper in a climatic chamber under defined
conditions (figure 26). In an extensive research
project, scientists at Hohenstein developed a
physiological evaluation model in the early 1990s
that could be used to derive the thermal range
of utility of a sleeping bag from these thermal
insulation values. The lower limits for this were
the “comfort” and “limit” temperatures at which
the “standard woman” or “standard man” begins
to feel cold in the sleeping bag. At the even lower
“extreme temperature”, the “standard woman”
would suffer from hypothermia. The “maximum
temperature” at which the sleeper sweats
excessively forms the upper limit for the range
of utility of the sleeping bag.
Body weight in kg
Freezing in a sleeping bag?
Figure 23: The
thermophysiological
properties of duvets or
mattresses are measured
using the articulated manikin
“Charlie 3”. Numerous
sleep tests with human test
subjects confirmed the
results of laboratory tests
and the assessment of sleep
comfort derived from this.
The climatic chamber makes
it possible to simulate a
wide range of environmental
temperatures.
TKcold
Figure 24: Using the body
weight of the sleeper and the
temperature in the bedroom,
the required individual
thermal insulation class of
the duvet can be derived
and a decision can be made
as to which of the two sleep
comfort ratings given on the
Hohenstein Quality Label is
relevant for this temperature.
TKwarm
Thermal insulation
Ambient temperature in °C
Figure 25: For duvets, the
Hohenstein Quality Label
provides information on the
front and reverse on the
thermal insulation class and
sleep comfort ratings in warm
and cold environments.
SAMPLE TESTED FOR:
SAMPLE TESTED FOR:
THERMAL INSULATION
Class 2
**
TEST-N0.: FI 09.4.XXXX
SLEEP COMFORT VOTE
warm climate:
1.2
(very good)
cold climate:
1.7
(good)
TEST-N0.: FI 09.4.XXXX
17
Clothing physiological research in the service of wear comfort
This measuring and evaluation method was
incorporated in the German standard DIN 7943-1
in 1995. This was replaced in 2002 by the European
standard EN 13537. Sleeping bag manufacturers
and retailers are now able to provide temperature
information for their products on an objective
and scientifically proven basis and are no longer
dependent on pure speculation. Many sleeping
bag manufacturers or retailers therefore have
their products tested at the Hohenstein Institute.
These tests are now particularly significant, as the
Product Liability Act passed throughout Europe
in 2005 makes the sleeping bag manufacturer or
retailer liable for the accuracy of the thermal limits
stated for the range of application.
as a ventilation effect between the body and the
seat, will the driver enjoy optimum seat comfort.
Otherwise, heat and moisture can accumulate,
which not only feels unpleasant but can also have
a negative effect on the driver, both physically
and mentally.
Numerous test with volunteers using a driving
simulator in a climatic chamber (figure 27) have
demonstrated that, from a physiological point
of view, the seat comfort is affected by the
following four parameters: the initial heat flow,
determining by the sensation of warmth in the
first few minutes after sitting down; the thermal
insulation adjusted to the climate in the vehicle
interior; the ability, known as “breathability”, to
transport any perspiration formed away from the
body as quickly as possible; and the extent to
which the seat is able to absorb water vapour
without feeling damp from a subjective point of
view (moisture buffering).
The “breathability” and moisture buffering of
the seat is determined using the Hohenstein
Skin Model, and the initial heat flow and thermal
insulation are measured using an Upholstery
Tester. With this device, in order to simulate the
heat lost from the human body, an aluminium
stamp in the form of a human bottom, heated to
skin temperature, is pressed down onto the seat
(figure 28). Heat flow sensors provide information
Comfort mobilises
Thermophysiological comfort of vehicle seats
plays a crucial role in road safety: Scientific
findings show that the performance of a driver
over long distances significantly decreases if
the car seats do not adequately support heat
and moisture balance as well as posture. This
leads to exhaustion and loss of concentration,
which in extreme cases, could result in serious
accidents.
Only if the material and design of a seat are
optimally coordinated, thus forming what is known
Figure 26: The articulated
manikin, “Charlie 3”,
measures the thermal
insulation of sleeping bags
according to the standard
EN 13537. This is used to
determine the thermal range
of application of the sleeping
bag.
18
+ 20 °C
Comfort zone
0 °C
-
6 °C
Transition zone
- 13 ° C
Risk zone
on how much heat the individual releases in the
first minutes after contact with the cold seat and
on the thermal insulation provided after a thermal
equilibrium has been achieved between the body
and the surface of the seat. Many well-known
car manufacturers and their suppliers have been
using the services of the Hohenstein specialists
for a number of years now to improve the quality
of their seats.
The next task of the Hohenstein scientists in
the field of vehicle seats is likely to be research
into construction elements for an “active climate
seat” which will always provide a pleasant
“microclimate” on the contact surfaces of the
body by means of sensor-controlled heating and
cooling elements.
Children are more than just small humans
Figure 27: Using test subjects, the physiological comfort of
vehicle seats is also tested in the climatic chamber using a
driving simulator.
Figure 28: The “Upholstery Tester” measures the initial heat
flow when first sitting down on the vehicle seats as well as
the effective thermal insulation while driving.
Due to the lower mass of a child’s body it can
only produce less thermal energy than the body
of an adult.
In addition, children‘s thermo-regulation ability
is by no means fully developed, meaning that
the body may react slowly or may not react at
all to changes in ambient temperature. What is
more, all their sweat glands have yet to become
active. As a result, the risk of becoming chilled
or overheating is disproportionately greater than
it is for adults.
These physiological differences are especially
important for the construction of bedding.
With the help of „Charlene“, a thermally
19
Clothing physiological research in the service of wear comfort
Figure 30: A thermoregulation model of a child
about four-years-old is used
at the Hohenstein Institute
to test and optimise the
sleep comfort for children's
bedding in particular.
Figure 29: Children‘s thermoregulatory systems are quite
different from those of adults.
As a result, the thermally
segmented test mannequin
„Charlene“ was brought into
service at the Hohenstein
Institute in 2008.
20
segmented mannequin developed at the
Hohenstein Institute, the sleeping comfort of
children‘s bedding can be evaluated and optimised
with respect to the special physiological needs
of children. „Charlene“ simulates the heat
generated by the human body, just as her adult
counterpart „Charlie 4“ does – with the aid of a
computer-controlled heating system. And just
as is the case with their human role models,
„Charlene“, who weighs 20 kilograms and is
92 centimetres tall, produces far less heat than
„Charlie 4“, who weighs in at 75 kilograms and
is 175 centimetres tall. Therefore, for a child to
stay comfortably warm beneath the bedcovers,
the amount of thermal insulation of children‘s
bedding must be increased accordingly.
Unlike „Charlie 4“, „Charlene“ is made of
synthetic materials rather than copper. A
computer-controlled heating system makes
it possible to regulate independently the heat
generated by six different segments of the body.
The rule of thumb here is that the more heat a
body part generates – meaning more energy is
required in that segment to maintain target skin
temperature, the lower the level of heat insulation
provided by the blanket for that segment.
In addition to its insulating effect, the sleeping
comfort of bedding is defined by its capacity to
absorb perspiration and draw sweat away from
the sleeper effectively. Because „Charlene“ does
not sweat, the measurements she contributes
are combined with those from the Hohenstein
skin model. The skin model enables assessments
of moisture transport resistance as a measure of
„breathability“, and perspiration transport, sweat
buffering, and drying time of the textile materials
used as well.
The battle against cold hands and
perspiring feet
In cooler ambient temperatures, the large surface
areas of skin on the fingers and toes lose far
more heat relative to their weight than say, for
example, is lost from a person‘s trunk. In order to
maintain comfortable skin temperatures for these
parts of the body, the thermal insulation of socks,
shoes and gloves must be accordingly high. At
the same time, the processed textile materials
must absorb sweat and draw perspiration away
from the body very effectively, particularly during
physical activity.
In the „sweating hand“ and „sweating foot“
models, the functional principles of the skin model
Figure 31 on the left: Thermoregulation models of the
human hand are used to
measure moisture and heat
emissions in order to assess
the wear comfort of gloves
under realistic conditions.
Figure 32 on the right: In
order to investigate the
thermal wear comfort of
socks and shoes, the special
wearing conditions featured
by the human foot must be
taken into consideration.
and thermally segmented testing mannequins
have been combined, i.e. they generate both
moisture and heat. For the first time, this allows
researchers to simulate as realistically as
possible the special thermal characteristics of
human extremities.
Up until now, all the materials used in shoes
and socks had to be tested individually with the
aid of the skin model as well to assess reliably
the wearing comfort of these combinations.
Extrapolation scenarios for garments, however,
nevertheless allowed for values approaching
actual data. Reliable, and above all differentiated,
assessments for individual areas of the foot
are now possible with the aid of the „sweating
foot“.
The „sweating hand“ and „sweating foot“ are
constructed in markedly different ways. The
thermo-regulation model of the human hand
simulates the human hand with a membrane-like
material that is permeable to moisture and emits
moisture along its entire surface. The „sweating
foot“ is made of thirteen metal parts and sweat
is emitted from 32 individual valves. In order to
account for the major role ventilation plays in
the thermal comfort of footwear, motorised fans
were used to simulate the aerodynamic effect
of walking by moving air around the „sweating
foot“.
One thing all the clothing physiology measuring
equipment has in common is that the lion‘s
share of development time was devoted to
implementing complex control and measurement
technologies. In order to measure precisely
the amount of perspiration emitted and the
energy required to maintain a comfortable skin
temperature, the team led by Professor KarlHeinz Umbach had to move into technologically
and scientifically uncharted territory as they
designed the thermally segmented mannequin
„Charlie 4“ and the Hohenstein skin model.
Now manufacturers world-wide can profit from
the knowledge they gained – ultimately leaving
consumers to enjoy optimised textile products
whether they are relaxing or on the job.
Clothing physiological measurement
methods at a glance
In testing the wearcomfort of textiles, a
fundamental distinction is made between thermophysiological aspects – i.e. the management of
warmth and moisture, and how the textile feels
on the skin (skin sensibility).
21
Clothing physiological research in the service of wear comfort
Thermo-physiological measurement
methods
• The Hohenstein Skin Model
The Hohenstein Skin Model simulates the way
the skin emits heat and moisture. It consists of a
sintered, porous metal plate that can be warmed
electrically and to which water is supplied. It is
located in a climate-chamber, a space where
the most diverse environmental conditions can
be simulated. Temperature, humidity and the
movement of air can be set as desired.
For substances and fabrics, measurements taken
using the skin model supply specific parameters
such as, for example, thermal insulation and
moisture transport resistance a measure for
„breathability,“ perspiration transport and sweat
buffering, and drying time, etc. These parameters
characterise the thermo-physiological quality of
textile materials
• Thermally Segmented Testing Mannequins
„Charlie 3“, „Charlie 4” and „Charlene“
Figure 33:
The Hohenstein Skin Model
consists of a sintered, porous
metal plate that can be
warmed electrically and to
which water is supplied.
22
The thermal insulation of ready-made garments,
bedding and sleeping bags can be measured with
the help of the thermally
segmented testing
mannequins „Charlie
3“, „Charlie 4“ and
„Charlene“ who were
also developed at the
Hohenstein Institute.
Using what are known
as human thermoregulation models,
the heat generated by
adults and children is
set. The segmented
mannequins are made
of copper or synthetic
materials and have been
fitted with a computer-controlled heating system
that allows the heat generation for different
parts of the body to be regulated individually and
independently of one another. The more heat
emitted from the arms or legs, for example, the
worse the thermal insulation of the garment is
for those areas of the body. These figures are
very significantly influenced by the movement
of air when the body is in motion. Therefore the
segmented mannequin „Charlie 4“ has been set
up so he is able to move during testing as if he
were out for a brisk walk.
The assessments made using the thermally
segmented testing mannequins are an important
complement to those made using the skin
model, because the influence of the way the
item or garment is made (fit, elasticised cuffs,
turtlenecks, etc.) can be taken into consideration.
But because the „Charlies“ and „Charlene“ can
do all this without breaking a sweat, moisture
management – and with it a significant aspect of
thermo-physiological wear comfort – can only be
evaluated when the results of tests made on the
skin model are available to use as a basis.
• Thermal regulation models „sweating hand“
and „sweating foot“
In the „sweating hand“ and „sweating foot“
models, the functional principles of the skin model
and the thermally segmented testing mannequins
have been combined, i.e. emissions of heat
and moisture in controlled climatic conditions.
With the measuring instruments that came into
operation at the Hohenstein Institute in 2008,
the thermal insulation and breathability of gloves,
socks and shoes can be evaluated.
• Upholstery Testing Device
Whether a car is parked outside in winter or in the
summer sun, it always takes awhile for the seats
to become comfortable. By using an upholstery
testing device, it is possible to measure the
impression of temperature (initial heat flow) that
a person has when they first make contact with
the car seat. In addition, the thermal insulation
of the seats can also be tested during longer
trips made in the most varied of surrounding
temperatures.
• Human Test Subjects
Thermo-physiological comfort can be objectively
measured and assessed with the Hohenstein
Skin Model and the thermally segmented test
mannequins ‚Charlie‘ and ‚Charlene‘. In order
to develop these testing methods and the
assessment models that have become established
world-wide in the sector of clothing physiology
today, it was necessary to run numerous series
of tests on human test subjects. They still come
to the Hohenstein Institute even today if a
completely new product is being developed or
to confirm the results of tests carried out using
the skin model and the thermally segmented test
mannequins.
Figure 34: Ongoing test series
at the thermal regulation
model „sweating foot“.
• Climate chambers
The most varied of environments can be created
in the climate chambers at the Hohenstein
Institute. Temperatures can range from - 25 °C
to + 50 °C making, for example, testing sleeping
bags possible under extreme conditions. A
precipitation system can be used to create rain
of a wide-range of intensities, and a warm wall
simulates intense sunshine or heat as real as
that from open fire, especially when it is a matter
of testing the wear comfort of fire-fighters’
clothing.
Fans, a driving simulator used by people testing
car seats, and basins in which ‚Charlie 3‘ is
immersed in order to assess the survival time of
pilots in extreme conditions, such as submersion
in ice water, round out the standard equipment of
the Hohenstein climate chambers.
Measurement methods for skin sensibility
Along with the heat and moisture management
characteristics of textiles, skin sensibility is one
of the significant aspects that influences wear
comfort. Garments worn close to the skin should
not „cling“ to its surface. It should also transport
large amounts of perspiration to layers of clothing
further away from the skin. In order to meet the
comfort standards dictated by skin sensibility,
the construction of the textile base material of
which the garment is made has the most relevant
role to play.
To assess the surface structure of textile
substances in order to gauge their comfort in
terms of skin sensibility, a number of different
laboratory tests have been developed at
the Clothing Physiology Department of the
Hohenstein Institute.
Figure 35: Only through
numerous experiments with
human test subjects during
the past decades has it
been possible to make the
extrapolations required to
correlate human perceptions
with laboratory results.
Series of tests with volunteers
are in the meantime primarily
limited to the evaluation of
completely new products and
confirmation of tests carried
out on the skin model and
thermally segmented test
mannequins.
Figure 36: Fans, warm walls,
etc. are used to simulate
the most varied of climate
conditions in the four climate
chambers of the Hohenstein
Institutes.
23
Clothing physiological research in the service of wear comfort
• Cling index
• Stiffness
A porous, sintered plate of glass to which water
is supplied using a calibrated motorised burette
simulates perspiring skin. The textile specimen
is fastened to a cylinder and pulled across the
plate.The force required to do this supplies what
is called the cling index, which is used to evaluate
whether the textile will cling uncomfortably to the
skin when the wearer is sweating.
For determining the stiffness or bending angle
of a textile substance a laser measurement is
taken on a strip of fabric that has been placed
on a thin bar.
Based on their years of experience, the
scientists at Hohenstein have defined standards
for products and areas of use that guarantee
optimal wear comfort and rule out mechanical
skin irritations caused when stiffness is too
great.
• Number of contact points and surface index
Figure 37: The speed at
which the material absorbs
perspiration is detected
with the aid of continual
measurement of the contact
angle of a water droplet on
the surface of a textile.
A surface scanner, or alternatively, a microscope
linked to an image analysis system shows the
number of contact points for the textile
and surface index.
This indicates how much the contact surface the
textile material has with the skin and the hairiness
of its surface. During decades of research, the
scientists at Hohenstein have defined threshold
values for the optimum number of contact points
and the surface index.
• Sorption index
Skin becomes more sensitive to mechanical
irritation as moisture increases. As a result,
it is advantageous for sensitivity and wear
comfort when a textile substance transports
perspiration away from the skin as quickly
as possible. The sorption index is the speed
at which a textile absorbs the drops of water
with which it comes into contact. A drop of
water is placed on the textile specimen and
observed using a video camera. The angle of
contact of the drop of water on the textile‘s
surface is continually monitored and recorded,
indicating how quickly the material is able to
absorb sweat.
One mark for wear comfort
The results of the tests carried out on the skin
model and thermo-regulation models all come
together with assessment of skin sensibility
to make up one grade known as wear comfort
or sleep comfort. This is possible because
research results have shown, that, for example,
in the case of garments worn daily, thermophysiological characteristics account for about
66% percent and skin sensibility for about 34%
of perceived wear comfort.
Evaluation of wear comfort is done according to
the German school grading system, where 1 is
„very good“ and 6 is „unsatisfactory“.
The comfort marks are used today by numerous
manufacturers in the form of the Hohenstein
Quality Label.
These are attached to the product and allow
the consumer to make a simple comparison
between different products.
24
Figure 38: A porous, sintered
plate of glass to which water
is supplied using a calibrated
motorised burette simulates
perspiring skin. The textile
specimen is fastened to a
cylinder and pulled across
the plate. The force required
to do this supplies what is
called the cling index, which is
used to evaluate whether the
textile will cling uncomfortably
to the skin when the wearer is
sweating.
Figure 39: A series of
measurement methods are
used to assess the skin
sensibility characteristics of
textiles within the scope of
the physiological tests at the
Hohenstein Institutes. Among
them are the measurement of
stiffness, which is recorded
and included together with
other measurements to
determine wear comfort.
25
Clothing physiological research in the service of wear comfort
„Charlie 4“
„Charlene“
Hohenstein
Skin Model
„Sweating Hand“
„Sweating Foot“
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Thermo-regulation
model
A "standard" adult
male
A "standard" fouryear-old child
Human skin
Human hand
Human foot
Height/Weight/Size
175 cm, 75 kg
92 cm, 20 kg
20 cm x 20 cm in a
climate-chamber
Glove size 9
Shoe size 43
Measurements
Thermal insulation
Thermal insulation
Moisture transport
resistance
(breathability)
•Thermal insulation
• Moisture transport
resistance
(breathability)
Products tested
26
•Thermal insulation
• Moisture transport
resistance
(breathability)
•Sweat buffering
• Perspiration
transport
Ready-made products: Ready-made products: Fabrics: textile
materials of all types
garments of all types, children's bedding
bedding and sleeping and sleepwear
bags
Ready-made products: Ready-made products:
gloves
socks and sock-shoe
combinations
Material and colour
Copper painted
black, to simulate
the physical heat
generation of the
human body as closely
as possible
Sintered metal plate
Plastic with a black
coating, to simulate
the physical heat
generation of the
human body as closely
as possible
Membrane material
stretched over a wire
frame
Metal segments
Heating system
Individually
controlled electric
heating elements
in 16 segments, for
evaluation of thermal
insulation for different
parts of the body
Individually
Electric heaters
controlled electric
heating elements
in 6 segments, for
evaluation of thermal
insulation for different
parts of the body
Hot water circulating
systems
Individually controlled
electric heating
elements in 13
segments, to evaluate
thermal insulation for
different parts of the
foot
Measurement points
In 16 segments
In 6 segments
In a segment
In a segment
In 13 segments
Perspiration
None
None
Via membrane material Via 32 sweat valves
due to the partial
aided by a medical
pressure difference of (water) pump
moisture between the
„sweating hand“ and
its surroundings
Mobility
Complete range of
motion for all "human"
joints. To account
for the movement of
air around a person
walking, these motions
are simulated when
testing garments.
Complete range of
motion for all "human"
joints. Walking
movements are not
yet simulated due
to the items that are
currently being tested
•Vaporous, through
pores on the entire
surface due to the
partial pressure
differentials of
water between the
skin model and the
surroundings
• Liquid across the
entire surface
through spray valves
Stretching as well as
static and dynamic
pressure on the
material (such as car
seats for example) can
be simulated
None
Walking is simulated
Prof. Dr.-Ing. Otto Mecheels
Director of the Hohenstein Institute 1946 - 1962
1894
Born in Bönnigheim (Germany)
1929-1929 Head of dyeing at Amann & Söhne in Bönnigheim
1929
Appointed Professor at the Staatliche Technikum für Textilindustrie [State technical school for the
textile industry] in Reutlingen where he took charge of the department of textile chemistry
1935
Transferred to the Preussische Höhere Schule fur Textilindustrie Mönchengladbach as school
principal
1944
Following the destruction of the school in Mönchengladbach, returned to Bönnigheim with the
teachers and students in their final year. The around 60 people initially made use of the empty rooms
in the castle there – at the end of the war, they moved into the nearby Hohenstein Castle.
1946
Founded the Hohenstein Research Institute [Forschungsinstitut Hohenstein] as an independent
company, together with his wife, Lisel
1949
The Lehr- und Versuchsanstalt für die Bekleidungstechnik [Education and Research Institute for
Clothing Technology] is founded. This was renamed the Lehranstalt Hohenstein e.V. in 1954
1961
The Hohenstein Institute for Clothing Physiology [Bekleidungsphysiologische Institut Hohenstein e.
V. (BPI)] is founded as a publicly-funded interdisciplinary research institute
1962
Handed over leadership of the Institute to his son, Prof. Dr. Jürgen Mecheels
1979
Died at the age of 85 at Schloss Hohenstein
Prof. Dr. rer. nat. Jürgen Mecheels
Director of the Hohenstein Institute 1962 - 1995
1928
Born in Stuttgart (Germany), the son of Prof. Dr. Ing. Otto Mecheels
1958
Degree in textile chemistry at the University of Heidelberg
1961-1961 Doctorate and development of a thermoregulatory functional model of the skin (Skin Model)
1961-1962 Worked as a scientist at the Hohenstein Institute and a lecturer at the Hohenstein Technical
Academy
1995-1995 Head of the Hohenstein Institute
1988 Appointed professor by the Minister President of Baden-Württemberg,
Dr. Lothar Späth
1996
Awarded the Cross of the Order of Merit of the Federal Republic of Germany
2006
Died at the age of 78
Prof. Dr. rer. nat. Karl-Heinz Umbach
Head of the Department „Clothing Physiology“ at the Hohenstein Institute (1976 - September 2009)
Deputy Head of the Bekleidungsphysiologisches Institut Hohenstein e.V. (1995 - September 2009)
1944
Born in Stetten/Remstal (Germany)
1971
Degree in physics at the University of Stuttgart
1971-1976 Research assistant at the 2. Physikalisches Institut at the University of Stuttgart
1975
Doctorate in the field of solid state physics
Since 1976 Employed at the Hohenstein Institute:
around 190 publications in the field of clothing physiology
Since 1982 Chairman of four and member of 15 national and international standards committees
(e.g. for protective clothing)
1995
Adjunct Professor at the North Carolina State University, Raleigh NC, USA
1996
Honorary professor at the University of Kassel
Dr. rer. nat. Andreas Schmidt
Director of the Department „Function and Care“ at the Hohenstein Institute (since October 2009)
1974
1999
1999 - 2002
2002 - 2008
2008 - 2009
Since 2009
Born in Monheim am Rhein
Degree in chemistry at the Heinrich-Heine-University, Düsseldorf
Research associate at the German Textile Research Center North-West e.V., associated institute to the Gerhard-Mercator-University Duisburg
Head of laboratory at Henkel KGaA, Laboratory: Textile Fibers
Several functions in the field of product development at Henkel AG & Co. KGaA
Director of the Department „Function and Care“ at the Hohenstein Institute
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