DE102007034724
[0001] The invention relates to a method for preparing a
composition, is dispersed in an aqueous solution in which at
least one gel-forming substance. The invention also relates
to a composition, in particular for coating surfaces, which
consists at least from an aqueous solution and at least one
gel-forming substance.
[0002] Sol-gel processes are wet processes, which are for
example the deposition of homogeneous, nano-crystalline
ceramic oxide coatings or keramischorganischer used. The
special feature of sol-gel process is that the production of
coating each of a liquid sol state proceeds, which is
converted by a sol-gel transformation into a solid gel
state.As brine dispersions of solid particles in the size
range be used between 1 nm to 100 nm, which are dispersed in
water or organic solvents. Sol-gel process usually go out of
brines based on organometallic polymers. The transition from
a liquid sol is then used for coating each of the gel state,
where there is a three-dimensional network of nanoparticles
in the solvent, so that the gel is replaced by solid state
properties.The transfer of the gel into a solid oxide
coating is controlled by a heat treatment in air.
[0003] Sol-gel coatings influence the properties of
surfaces. Depending on the nature of the brine and its
impurities, hard and scratch-resistant surfaces are
generated by such a coating. Sol-gel coatings can be
performed on metals, glasses, synthetic and natural
polymers.There exist in this area a number of patents and
publications, both of which are only mentioned a few
examples (HK Schmidt, Organically modified silicates as
inorganic-organic polymers, RM Laine (Ed.), Inorganic and
Organometallic Polymers with special properties, 297-317 ,
1992 Kluwer Academic Publishers, Netherlands; CJ Brinker and
G. Scherer, Sol-Gel Science. The Physics and Chemistry of
Sol-Gel Processing, Academic Press, Boston, MA (1990); H.
Böttcher, K.-H.Kallies, T. Textor, E. Schollmeyer, T.
Bahners, DE 197 56 906 A (1999); H. Böttcher, J. Trepte,
K.-H. Kallies, DE 19839292 (2000).
[0004] The simultaneous hydrolysis of inorganic salts and
organic silanes gives coatings with an adjustable
flexibility to each other depending on the ratio of the
inorganic and organic components (T. Textor, D. Knittel, T.
Bahners, E.Schollmeyer, Inorganic-organic hybrid polymers
for coating textile materials, Current Trends in Polymer
Science, Vol 8, 2003, page 127-133).
[0005] The chemical compounds that are capable of volatile
and other organic compounds bind to, are known
cyclodextrins. These are macrocyclic molecules, which are
constructed from six, seven or eight [alpha]-D-glucose
units. There are ring-shaped molecules that possess a
hydrophobic cavity.In this cavity a number of organic
molecules is deposited. This changes the physical and
chemical properties of the embedded molecules. The embedded
molecules possess, for example, compared to the free
molecules, a much lower vapor pressure and an improved
stability against degradation by light or oxygen. For this
reason, cyclodextrins have been used for many years in the
field of cosmetics and pharmaceuticals (J.Szejtli,
Cyclodextrin Technology, Kluwer, Dordrecht, 1988).
[0006] A permanent fixation of cyclodextrins on various
textile materials is known (for BH-J Buschmann, D. Knittel,
E. Schollmeyer, DE 4036328;. DE 40 35 378 A and DE 100 60
710 A). The binding of the cyclodextrins by chemical bonds
or physical interactions, so that their removal by washing
processes is not possible.
[0007] The removal of odors andthe fragrance of textile
materials with the aid of cyclodextrins or cyclodextrin
derivatives is also known (eg, T. Trinh, JM Gardlik, TJ
Banks and F. Benvegnu U.S. 5,094,761, JM Gardlik, T. Trinh,
TJ Banks and F. Benvegnu 5.23461 million U.S., T . Trinh, JM
Gardlik, TJ Banks and F. Benvegnu EP 0392607 and JM Gardlik,
T. Trinh, TJ Banks and F. Benvegnu, EP-A-0 392 606).The used
cyclodextrins have no affinity for the fiber material so
that they do not adhere to the textile materials.
[0008] The adsorptive accumulation of cyclodextrins with
substituted polyethylene glycols of various materials, such
as hair and textile materials is well known (A. Schmidt, O.
Lammerschop and H. Küster, DE 103 44 967 A). These
cyclodextrin derivatives can partlybe a normal household
washing process removed from the surface of materials.
[0009] The object of the invention to provide cyclodextrins
for sol-gel process and available to provide an improved
method and an alternative composition for coating surfaces.
[0010] This object is inventively achieved by a method for
preparing a composition of the aforementioned kind in which
the dispersion is at least one cyclodextrin added.
[0011] In an advantageous embodiment of the inventive method
provides that the cyclodextrin at a final concentration of
0.1 to 20 wt -%, preferably 0.1 to 15 wt -%, more preferably
0.1 to 10 wt -%, especially 0.1 to 5 wt-% Is added.
[0012] In an alternative advantageous embodiment of the
inventive method provides that the cyclodextrin derivative
in a final concentration of 1 to 20 wt -%, preferably 5 to
20 wt -%, preferably 10 to 20 wt -%, especially 15 to 20
weight -% is added.
[0013] In an alternative advantageous embodiment of the
inventive method provides that the cyclodextrin at a final
concentration of 0.1 to 15 wt-%, Preferably 5 to 10 wt -%,
particularly preferably from 1 to 5 wt -%, especially 2 to 4
wt -% is added.
[0014] According to the invention it is particularly
advantageous when the partially methylated cyclodextrin
[beta]-cyclodextrin and / or
hydroxypropyl-[beta]-cyclodextrin is added to /.
[0015] Here, the cyclodextrin in the dispersion may be
dissolved or dispersed.
[0016] To cyclodextrins for use in a sol-gel method to make
use of, d.h. the cyclodextrins to embed in a coating is
advantageously provided that a cyclodextrin is prepared by
reacting with polyvinylamines, polyethyleneimines
aminosiloxanes, alkylamines with 3 to 12 carbon atoms in the
alkyl group, chitosan, polyvinyl alcohols and / or
Perfluoroalkylaminen.
[0017] The novel cyclodextrin derivatives can be fixed in
the coating, such as a silicon oxide coating, by their
substituents, which act almost as anchor molecules. Due to
the inventive derivatization or modification of
cyclodextrins is also advantageously able to handle these
useful materials in a sol-gel process and permanently
integrate into an ultra-thin coating.
[0018] In a further advantageous embodiment of the inventive
method is provided that can be stored in the
Cyclodextrinderivatmoleküle organic substances. It may be,
for example to insecticides, fungicides, biostatic or
biocidal agents, fragrances and / or therapeutic agents.
[0019] In an advantageous embodiment of the inventive method
is further provided that is dispersed as a gel-forming
material at least one metal oxide or a mixture of metal
oxides in aqueous solution, preferably SiO2, Al2O3, ZrO2,
TiO2 and / or R VerSiOn with R = H , alkyl, aryl,
epoxy-alkyl, aminoalkyl, and n = 1.5 or 1
[0020] According to the invention the object is also
achieved by following the methods described above prepared
composition.Such a composition is advantageously used for
coating surfaces in a sol-gel method.
[0021] The object is further achieved by a composition of
the type that includes at least one cyclodextrin. Such a
composition is also advantageously used for coating surfaces
in a sol-gel method.
[0022] In an advantageous embodiment of the inventive
composition is provided that the cyclodextrin at a final
concentration of 0.1 to 20 wt -%, preferably 0.1 to 15 wt
-%, more preferably 0.1 to 10 wt -%, especially 0.1 to 5 wt
-% is included.
[0023] In an alternative embodiment of the inventive
composition is provided that the cyclodextrin derivative in
a final concentration of 1 to 20 wt-%, Preferably 5 to 20 wt
-%, preferably 10 to 20 wt -%, especially 15 to 20 wt -% is
included.
[0024] In an alternative embodiment of the inventive
composition is provided that the cyclodextrin at a final
concentration of 0.1 to 15 wt -%, preferably 5 to 10 wt -%,
particularly preferably from 1 to 5 wt -%, especially 2 to 4
weight -% is included.
[0025] Preferably, the cyclodextrin derivative according to
the invention a partially methylated [beta]-cyclodextrin or
hydroxypropyl-[beta]-cyclodextrin.
[0026] In an advantageous manner can be stored more organic
substances in the novel cyclodextrin derivative, preferably
insecticides, fungicides, biostatic or biocidal agents,
fragrances and / or therapeutic agents.As therapeutic
agents, for example, anti-inflammatory and / or
wound-healing agents.
[0027] In an advantageous embodiment of the inventions
according to the composition is further provided that the
gel-forming substance is at least one metal oxide or a
mixture of metal oxides, preferably SiO2, Al2O3, ZrO2, TiO2
and / or R VerSiOn with R = H, alkyl, aryl , epoxy-alkyl,
aminoalkyl, and n = 1.5 or 1
[0028] The invention also relates to a method for coating
surfaces, in which a sol is applied from an aqueous
solution, at least one gel-forming substance and at least
one cyclodextrin derivative to a surface and then dried.
This method is particularly advantageous when the coating is
at least partly from the composition of the invention is or
has been made of this.The cyclodextrin derivatives according
to the invention are derivatized so that they can be
processed in a sol-gel process and permanently incorporated
into a coating produced in this process.
[0029] Preferably the sol is sprayed onto either the surface
or the surface immersed in the sol. In both cases,
advantageously produces an ultra-thin coating that uniformly
covers the so-coated article.
[0030] The sol can be applied for example to a textile
material, a nonwoven fabric made of natural or synthetic
polymers or mixtures of these polymers. Alternatively, the
sol can also be applied to an inorganic fiber material,
preferably glass fibers, carbon fibers and / or ceramic
fibers, or metallic, ceramic, glass-like and / or cellulosic
materials.In a particularly preferred embodiment of the
invention, the sol also on plastics or plastic-like
materials are applied.
[0031] The inventive composition is particularly suitable
for coating of textile materials and / or leather,
preferably clothing, shoes, diapers, wound dressings or
office equipment, interior trim and other interior fittings
of motor vehicles, trains and airplanes.In these
applications, in particular, the odor-binding properties of
the composition and the ability to store active substances
in the cyclodextrin advantage of
[0032] Also advantageous is the use of the composition for
coating plastics, preferably sanitation or interior trim and
other interior fittings of motor vehicles, trains and
airplanes.Examples are toilet lids and seats and plastic
components in motor vehicles, the latter being bound in a
coated form not only smell, but no self-interference, due to
production have more odor. Is also particularly advantageous
to coat the plastic housings of mobile phones with coatings
that are embedded in the antimicrobial substances and / or
fragrances.
[0033] The invention also includes any object with a
nonstick surface, which was prepared by the method of the
invention and / or in which the coated surface comprises the
composition of the invention.
[0034] The invention relates for example, ultra-thin
coatings that are produced by a sol-gel process and have the
addition to the known properties still an odor-reducing
properties.Likewise, a storage of insecticides, fungicides
or other agents into the possible in the sol-gel coating
located Cyclodetrinderivate. The embedding of the active
ingredients in the cyclodextrin their stability to
degradation by exposure to light and oxygen is greatly
increased. For drugs that have a higher vapor pressure,
evaporation is prevented by the incorporation in the
cavities of the cyclodextrin.
[0035] According to the invention has been shown that some
of cyclodextrin so in a sol-gel matrix can be stored, that
the cavities of the cyclodextrins remain still accessible.
This can produce sol-gel coatings that have both a
protective layer, or another functional layer formed on the
surfaces of textile materials, woven fabrics, glass fibers,
metals, ceramics or wood and have the same odor-reducing
properties.In addition, a variety of organic compounds are
incorporated into the cyclodextrins, which are released only
by moisture and get back to the surface of the coating.
[0036] Known brine based on pure aqueous solutions or
mixtures of water and alcohols. It can be used preferably
metal oxide xerogels of SiO 2, R VerSiOn, Al2O3, ZrO2, TiO2
or mixtures thereof, where R = H, alkyl, aryl, epoxy-alkyl,
aminoalkyl, and can be n = 1.5 or 1.As unsuitable for
incorporation into the starting sols has been shown
[beta]-cyclodextrin. Its solubility in the brine is too low.
Sols in alcoholic form [alpha] -, [beta] - and
[gamma]-cyclodextrin precipitation. Such solutions are not
suitable for the sol-gel process.
[0037] The invention therefore relates to the production
example, cyclodextrin-salt, which can be in a conventional
sol-gel process as thin or very thin coating is applied
uniformly to different materials.
[0038] The invention also relates, for example brine
containing 0.1 weight -% contained, a cyclodextrin
derivative -% to 10 wt -%, preferably 1 wt -% to 5 wt.These
solutions can be applied both in a dipping process as well
as by spraying onto the desired substrate. After drying, a
coating has formed on the basis of polymerized SiO2.
[0039] are in principle the following cyclodextrin
derivatives for incorporation in the composition of the
invention: partially methylated [beta]-Cyclodextrin (CAVASOL
<(R)> W7 M, Wacker-Chemie) and
hydroxypropyl-[beta]-Cyclodextrin (CAVASOL <(R) > W7
HP, Wacker-Chemie).Starting with a cyclodextrin derivative
with a reactive group, such as
monochlortriazinsubstituiertes [beta]-cyclodextrin (CAVATEX
W7MCT, Wacker Chemie GmbH, Burghausen) or other cyclodextrin
derivative with a reactive group (A. Schmidt, H.-J.
Buschmann, E . Schollmeyer, DE 101 55 781 A) or the reaction
product of acrylic acid or an acrylic acid derivative with
an unsubstituted cyclodextrin, for example,
thispolyvinylamine (ZD1168/69-3, BASF, Ludwigshafen,
Germany), polyethylenimine (Chemos GmbH), amino siloxane
(DMS-A12, ABCR), alkylamines (Merck), dialkyl amines
(Fluka), chitosan (Sigma-Aldrich), polyvinyl alcohol (Fluka)
, Perfluoralkylamin (Perfluorononylamin, Fluka), amino acids
such as glycine (Fluka), implemented. Among cyclodextrins
[alpha] are - to understand and [gamma]-cyclodextrin -,
[beta]. The above-mentioned reactive derivatives formed, for
exampleby reaction of [alpha] -, [beta] - and
[gamma]-cyclodextrin with cyanuric chloride and acrylic acid
or acrylic acid derivatives.
[0040] The reaction products are water-soluble cyclodextrin
derivatives mentioned above can be added to the sol as a
concentrated solution or as a pure substance. After a
homogeneous solution is formed, it can go no further
preparations for the application.Of the non-water-soluble
cyclodextrin derivatives, is produced using ultrasound, a
dispersion. This is mixed with the corresponding sol and
applied to a homogenisation of the surface to be equipped.
[0041] The inventive method has the advantage that the
sol-gel process is combined with equipment to adsorb odors
and other organic substances.Through the use of cyclodextrin
derivatives described the effect of odor control is
permanent. These cyclodextrin derivatives are anchored by
their substituents at the silicon oxide coating. On the
other hand, the accessibility of the cyclodextrin cavities
is guaranteed, leaving the complex-forming properties of the
cyclodextrins.
[0042] The cyclodextrin-salt can be applied to metallic and
ceramic surfaces by a dipping or spraying. After drying, a
thin layer has formed on the surface that is mechanically
stable against external influences.
[0043] The cyclodextrin composition is also suitable for the
impregnation of porous inorganic materials.By immersion of
these materials into suitable brine, they reach into all the
pores by capillary forces. After centrifugation, excess sol
from the pores are removed. After drying, the surfaces of
the pores are coated by the sol, the pores of the material
has been preserved.
[0044] Natural materials such as wood and paper can be
impregnated by dipping into the corresponding
cyclodextrin-Sole.In this cause the brine one
hydrophobicisation the surface. In addition, the
cyclodextrins can be chemical agents against pests are
stored. This leads to an improved wood preservation.
[0045] Insulating materials that are made from mineral or
natural fiber materials can be impregnated by immersion in a
brine cyclodextrin. After drying, the cyclodextrin cavities
with organic substances, such asInsecticides and fungicides
are loaded. By coating with the sol, the combustibility of
the insulating material is reduced from natural fiber
materials. The loading of the cyclodextrins with
insecticides and / or fungicides reduce the pest infestation
and / or infestation by fungi. Another advantage is that do
not evaporate at high temperatures, the active ingredients
from the cyclodextrin cavities.This ensures that occurs does
not pollute the air by these substances.
[0046] Flexible materials such as films, nonwovens and
textile fabrics, can be fitted by spraying or by a dipping
process with the cyclodextrin-sols. Depending on the amount
of the sol is applied to the flexible structure of the
material received. The sol in fixed cyclodextrins are able
to store chemical substances from the air. They may, for
example by sprayingAs with perfumes and other fragrances are
loaded.
[0047] A load of other organic substances such as
insecticides, fungicides, bactericide or biostatically
acting substances or pharmaceutical active substances is
possible. By deposition of insecticides and fungicides, for
example, a parasitic infestation of the materials is
prevented.
[0048] After the finishing of nonwovens and / or textile
fabrics with cyclodextrin brines can be loaded onto the
cyclodextrin derivatives with pharmaceutical and / or
cosmetic agents. Come such a finished textile materials in
contact with human skin, so the stored substances are
released by the moisture on the skin surface of the skin.The
sol-gel coating prevents their hydrophobic properties, the
growth of skin cells, if such fabrics are used as wound
dressings. By the release of substances that have been
stored in the cyclodextrins, the healing process of wounds
is accelerated.
[0049] The embedding of the cyclodextrin derivatives in a
sol-gel coating ensures that the cyclodextrins can be
removed by washing processes or similar processes from the
surface of the treated materials. It is therefore considered
a permanent modification of the surface of the corresponding
materials.
[0050] The invention is further illustrated by the following
embodiments as an example.
Example 1
[0051] To a mixture of 50 ml of tetraethoxysilane, 15 ml of
3-glycidyloxypropyltrimethoxysilane and 40 ml of ethanol are
added 10 ml of 0.01 N HCl and stirred at room temperature
for 10 hours. Then 20 ml of a 10 wt -% solution added to the
polyvinylaminsubstituierten cyclodextrin and stirred an
additional hour. The result is a water-clear sol. To this
sol, a 10 wt -% solution of ZrOCl 2 * 8H2O in 50 weight -%
ethanol added.This sol is applied to a polypropylene film
and dried.
[0052] By applying a drop of an alkaline phenolphthalein
solution on the surface, the accessibility of the cavity of
[beta]-cyclodextrin can be detected. They observed a
discoloration of the drop, which occurs only in the presence
of cyclodextrin (K. Beermann, H.-J. Buschmann, D. Knittel,
E.Schollmeyer, methods of determination of cyclodextrins in
textile materials, textile finishing, 37 (2002) 17).
Example 2
[0053] To a mixture of 30 ml of tetraethoxysilane,
diethoxysilane dimethyl-30 ml, 20 ml of
3-glycidyloxypropyltrimethoxysilane, 60 ml of ethanol are
added dropwise 15 ml of 0.01 N HCl in 50 ml ethanol and
stirred at room temperature for 10 hours. Then 20 ml of a 15
wt -% solution added to the polyethyleniminsubstituierten
cyclodextrin and stirred an additional hour.The result is a
water-clear sol. % Ethanol added - to this sol, a solution
of 10 wt -% Al 2 (OH) 2-3H2O in 5Cl * 90 wt. The resulting
sol is using a padding applied to a wool fabric (wet pickup
80 weight -%) and the tissue dried.
[0054] The proof is the accessibility of the cyclodextrin
cavities with an alkaline phenolphthalein.
Example 3
[0055] To a mixture of 70 ml of tetraethoxysilane, 30 ml of
methyl triethoxysilane, 400 ml of ethanol are added 20 ml of
0.01 N HCl in portions and [deg.] Stirred at 25 C for
several hours. To this sol after which a solution of 10
weight -% Al 2 (OH) 2-3H2O in 5Cl * 80 weight -% ethanol and
30 ml of an aqueous dispersion (20 wt -%) added to the
aminosiloxansubstituierten cyclodextrin.The resulting
dispersion is applied to a cotton fabric using a sprayer and
dried.
[0056] The proof is the accessibility of the cyclodextrin
cavities with an alkaline phenolphthalein.
Example 4
[0057] To a mixture of 30 ml of tetraethoxysilane,
diethoxysilane dimethyl-30 ml, 20 ml of
3-glycidyloxypropyltrimethoxysilane, 60 ml of ethanol are
added dropwise 15 ml of 0.01 N HCl in 50 ml ethanol and
stirred at room temperature for 10 hours. Then 20 ml of a 15
wt -% solution added to the partially methylated
[beta]-cyclodextrin and stirred an additional hour. The
result is a water-clear sol. To this sol, a solution of 10
weight -% Al 2 (OH) 2-3H2O * 5Cl in 90 wt- Added% ethanol.
By dipping a piece of wood in the resulting sol is
impregnated them. After drying, the piece of wood at room
temperature, the sample is sprayed with a Permethrinlösung
in acetone. After drying, the wood is dipped briefly in
acetone to remove adsorbed permethrin. Evidence of complex
formation of cyclodextrin with permethrin is done by an
aqueous extraction of the wood piece.In the extract
permethrin by GC-MS analysis is proven.
QUOTES INCLUDED IN THE
DESCRIPTION
[0058] This list of documents cited by the applicant was
automatically generated and is included solely to better
inform the reader. The list is not part of the German patent
or utility model application. The DPMA is not liable for any
errors or omissions.
Patent literature cited
[0059]
- DE 19756906 A [0003]
- DE 19839292 [0003]
- DE 4036328 [0006]
- DE 4035378 A [0006]
- DE 10060710 A [0006]
- U.S. 5094761 [0007]
- U.S. 5234610 [0007]
- EP 0392607 [0007]
- EP 0392606 A [0007]
- DE 10344967 A [0008]
- DE 10155781 A [0039]
Non-patent literature cited
[0060]
- HK Schmidt, Organically modified silicates as
inorganic-organic polymers, RM Laine (Ed.) Inorganic and
Organometallic Polymers with special properties, 297-317,
1992 Kluwer Academic Publishers, Netherlands [0003]
- CJ Brinker and G. Scherer, Sol-Gel Science: The Physics
and Chemistry of Sol-Gel Processing. Academic Press, Boston,
MA (1990) [0003]
- T. Textor, D. Knittel, T. Bahners, E. Schollmeyer,
Inorganic-organic hybrid polymers for coating textile
materials, Current Trends in Polymer Science, Vol 8, 2003,
Page 127-133 [0004]
- J.Szejtli, Cyclodextrin Technology, Kluwer, Dordrecht,
1988 [0005]
- K. Beermann, H.-J. Buschmann, D. Knittel, E. Schollmeyer,
methods of determination of cyclodextrins in textile
materials, textile finishing, 37 (2002) 17 [0052]
WO 2009033635
SOL-GEL COATING OF SUBSTRATE
MATERIAL SURFACES WITH ODOR-ABSORBING PROPERTIES
The invention relates to sol-gel coatings,
which additionally has known about the properties still an
odor-reducing properties. Likewise, a storage of
insecticides, fungicides or other agents in the in the
sol-gel coating located cyclodextrins possible.The embedding
of the active ingredients in the cyclodextrins their
stability to degradation by exposure to light and oxygen is
greatly increased. For drugs that have a higher vapor
pressure, evaporation is prevented by the incorporation in
the cavities of the cyclodextrins.
The production and application of sol-gel coatings on
different materials is discussed below.
Sol-gel coatings influence the properties of surfaces.
Depending on the nature of the brine and its impurities,
hard and scratch-resistant surfaces are generated by such a
coating. Sol-gel coatings can be performed on metals,
glasses, synthetic and natural polymers. There exist in this
field a number of patents and publications, both of which
are only mentioned a few examples (HKSchmidt, Organically
modified silicates as inorganic-organic polymers, RM Laine
(Ed.), Inorganic and Organometallic Polymers with special
properties, 297 - 317, 1992 Kluwer Academic Publishers,
Netherlands; CJ Brinker and G. Scherer, Sol-gel Science: The
Physics and Chemistry of Sol-Gel Processing. Academic Press,
Boston, MA (1990); H. Böttcher, K.-H. Kaili, T. Textor, E.
Schollmeyer, T. Bahners, DE 19756906 (1999); H. Böttcher, J.
Trepte, K.-H. Kaili, DE 19839292 (2000).By the simultaneous
hydrolysis of inorganic salts and organic silanes gives
coatings with an adjustable flexibility to each other
depending on the ratio of the inorganic and organic
components (T. Textor, D. Knittel, T. Bahners, E.
Schollmeyer, Inorganic-organic hybrid polymers for coating
textile materials, Current Trends in Polymer Science, Vol.8,
2003, Page 127-133;. Bahners T., T. Textor, E.Schollmeyer,
Surface functionalization of textile fibers with reactive
silanes, in KL Mittal (Ed.), Silanes and Other Coupling
Agents, Vol 4 "s. 141-152, VSP, Leiden (2007)). Coatings by
the sol-gel method with a deodorizing effect can be produced
by the installation of catalytic additives (T. Benthien, P.
Faber, G. Jonschker, p. Sepeur, H. Schmidt, P. Stossel, DE
19,915,377 (1999)).These catalysts are able to decompose
organic substances at high temperatures.
As chemical compounds that are able to bind and other
volatile organic compounds, cyclodextrins are known. These
are macrocyclic molecules, which are constructed from six,
seven or eight [alpha]-D-glucose units. There are
ring-shaped molecules that possess a hydrophobic cavity. In
this cavity a number of organic molecules is deposited.This
changes the physical and chemical properties of the embedded
molecules. The embedded molecules possess as compared to the
free molecules, a much lower vapor pressure and an improved
stability against degradation by light or oxygen. For this
reason, cyclodextrins have been used for many years in the
field of cosmetics and pharmaceuticals (J. Szejtli,
Cyclodextrin Technology, Kluwer, Dordrecht, 1988).
Permanent fixation of cyclodextrins on various textile
materials is known (eg H.-J. Buschmann, D. Knittel, E.
Schollmeyer, DE 4036328 and DE 4035378 and DE 10.06071
million). The binding of the cyclodextrins by chemical bonds
or physical interactions, so that their removal by washing
processes is not possible.
The removal of odor or fragrance of textile materials with
the aid of cyclodextrins orCyclodextrin is also known (eg,
T. Trinh, JM Gardlik, TJ. Benvegnu F. Banks and U.S.
5,094,761, JM Gardlik, T. Trinh, TJ. Benvegnu F. Banks and
5.23461 million U.S., Trinh T., JM Gardlik, TJ. Banks and F.
Benvegnu EP 0392607 and JM Gardlik, T. Trinh, TJ. Benvegnu
F. Banks and EP 0392606). The used cyclodextrins have no
affinity for the fiber material so that they do not adhere
to the textile materials.
Adsorptive accumulation of cyclodextrins with substituted
polyethylene glycols of various materials, such as hair and
textile materials is well known (A. Schmidt, O. and H.
Küster Lammerschop DE 10,344,967). These cyclodextrin
derivatives can be partly through normal household washing
process removed from the surface of materials.
The use of cyclodextrins in the preparation of sol-gel
coatings is described in the literature on principle.Thus,
the embedding of native [alpha] -, ss-and
[gamma]-cyclodextrins described in a matrix of amorphous
silicon dioxide (F. Mizukami, M. Toba and S. Niwa U.S.
4,781,858 (1988) The embedding of the cyclodextrins. the
matrix improves the thermal stability of cyclodextrins.
coatings by the sol-gel method can also include
cyclodextrins, which act as carriers for active ingredients
(M. Dreja, W. Rybinski of DE 10,126,966 (2001)).Here, the
drug-loaded cyclodextrins are already used in the
manufacture of coatings. These agents can be re-released
from the cyclodextrin cavities. It is, however, described no
release mechanism. According to current knowledge, one must
assume, however, assume that the described in the
application of the matrix, drying the water molecules are
removed almost quantitatively.Small amounts of water are
required to produce drugs and other substances such as
perfumes, from the cyclodextrin cavities release (J.
Szejtli, Cyclodextrin Technology, Kluwer (1988), pages
188-190).
According to the invention has been shown that some of
cyclodextrin derivatives, egwith one or two substituents
such as polyvinyl amine, polyallylamine, polyethyleneimine,
polyethylene glycol and polyvinyl alcohols so in a sol-gel
matrix can be stored, that the cavities of the cyclodextrins
remain still accessible.These substituted cyclodextrins are
almost infinitely soluble in water or aqueous alcoholic
solutions, so that the disadvantages of low solubility of
ss-cyclodextrin in water and the native cyclodextrins
([alpha] -, ss-and [gamma]-CD) in aqueous alcoholic
solutions no longer exist.It is possible to produce
coatings, sol-gel, both a protective layer or other
functional layer formed on the surfaces of textile
materials, woven fabrics, glass fibers, metals, wood or
wood-like products such as paper, cardboard, etc., leather
or ceramics and have the same odor-reducing properties . The
coatings are formed even at room temperature. A thermal
treatment at temperatures above 40 [deg.] C is not required,
which allows the use even in very thermally sensitive
materials. Since the coatings formed are porous, can
subsequently a variety of organic compounds in the
cyclodextrins are stored, which are released only by
moisture and then get back onto the surface of the
coating.Since the accessibility of the cyclodextrin cavities
in the sol-gel coatings is given, the cyclodextrins in the
matrix chemical compounds bind in the air. Thus, the coating
has an odor-reducing properties. By treatment with an
aqueous solution can remove all the odor molecules from the
cyclodextrin, whereby the odor-reducing effect of the
coating with the cyclodextrin is restored.
Since the charge of cyclodextrins after formation of the
sol-gel coating is applied, is an influence of the sol-gel
process through the use of cyclodextrin avoided. In aqueous
and aqueous ethanolic solutions dissociate the cyclodextrin
used, so that by the previously may be adversely affected in
the cyclodextrins bound substances and active ingredients of
the sol-gel process.This drawback is not with the approach
described in this application given.
The used cyclodextrin derivatives have an effect biostatic.
Therefore, the use of additional chemical substances are not
required to obtain a biostatic or biocidal effect of the
coating. This makes it possible to produce sol-gel coatings,
which have simultaneously a biostatic or biocidal and an
odor-reducing effect.Known brine based on pure aqueous
solutions or mixtures of water and alcohols. Here are
preferably made of Si metal-oxide xerogels [theta] 2,
R-SiON, Al2O3, ZrO2, Ti [theta] 2 [theta] using the mixtures
thereof, where R = H, alkyl, aryl, epoxy-alkyl, aminoalkyl,
and n can be 1, 5 or 1. As unsuitable for incorporation into
the starting sols has proven ss-cyclodextrin. Its solubility
in the brine is too low.Sols in alcoholic form [alpha] -,
ss-and [gamma]-cyclodextrin precipitation. Such solutions
are not suitable for the sol-gel process.
The invention therefore relates to the provision of a
coating on a substrate, which is produced by the sol-gel
method from a cyclodextrin and brine can be as thin or very
thin coating is applied uniformly to different materials.
This problem is solved by a cyclodextrin-salt, are used in
the specific cyclodextrin in a special weight percent
interval in which the cyclodextrin is dissolved in the sol
or dispersion.
The invention therefore relates to a coating of a substrate
by the sol-gel process by cyclodextrin-salt, which is
characterized in that the 0.1 wt -% to 10 wt-% Containing a
cyclodextrin derivative that is dissolved or dispersed in
the sol.
These solutions / dispersions can be applied either in an
immersion process and by spraying or similar methods to the
desired substrate. After drying, a coating has formed on the
basis of polymerized SiO2.
According to a preferred embodiment, the coating is
characterized in that the cyclodextrin derivatives are
prepared by reaction with polyvinylamine, polyallylamine,
polyethyleneimine, aminosiloxanes, alkylamines with 3 to 12
carbon atoms in the alkyl group, chitosan, polyvinyl
alcohols and / or Perfluoroalkylamine.In principle, the
following cyclodextrin derivatives suitable for
incorporation in brine: partially methylated ss-cyclodextrin
(CAVASOL (R) W7 M, Wacker-Chemie) and
hydroxypropyl-ss-cyclodextrin (CAVASOL (R) W7 HP,
Wacker-Chemie). Starting with a cyclodextrin derivative with
a reactive group, such as monochlortriazinsubstituiertes
ss-cyclodextrin (CAVATEX W7MCT, Wacker Chemie GmbH,
Burghausen) or other cyclodextrin derivative with a reactive
group (A. Schmidt, H.-J. Buschmann, E.Schollmeyer, DE
10155781) or the reaction product of acrylic acid or an
acrylic acid derivative with an unsubstituted cyclodextrin,
is this example, with polyvinyl (ZD1168/69-3, BASF,
Ludwigshafen, Germany), polyethylenimine (Chemos GmbH),
amino siloxane (DMS-A12, ABCR) , alkylamines (Merck),
dialkyl amines (Fluka), chitosan (Sigma-Aldrich), polyvinyl
alcohol (Fluka), Perfluoralkylamin (Perfluorononylamin,
Fluka), amino acids such as glycine (Fluka),
implemented.Among cyclodextrins [alpha] are - to understand,
and ss-[gamma]-cyclodextrin. The above-mentioned reactive
derivatives are formed for example by reaction of [alpha] -,
ss-and yCyclodextrin with cyanuric chloride and acrylic acid
or acrylic acid derivatives.
The reaction products are water-soluble cyclodextrin
derivatives mentioned above can be added to the sol as a
concentrated solution or as a pure substance.After a
homogeneous solution is formed, it can go no further
preparations for the application. Of the non-water-soluble
cyclodextrin derivatives, is produced using ultrasound, a
dispersion. This is mixed with the corresponding sol, and
applied to a homogenisation of the surface to be equipped.
The erf [iota] ndungsmässe advantage of the described
coating or finish is that the sol-gel process is combined
with equipment to adsorb odors and other organic substances.
Through the use of cyclodextrin derivatives described the
effect of odor control is permanent. These cyclodextrin
derivatives are permanently anchored by their substituents
at the silicon oxide coating.On the other hand, the
accessibility of the cyclodextrin cavities is guaranteed,
leaving the complex-forming properties of the cyclodextrins.
According to a preferred embodiment, the coating is
characterized by the fact that this 1 wt -% to 5 wt -%,
contains a cyclodextrin derivative that is dissolved or
dispersed in the sol.
According to a preferred embodiment, the coating is
characterized in that the formation of the sol-gel matrix
[deg.] At temperatures between 15 <0> C and 40 C takes
place.
According to a preferred embodiment, the coating is
characterized in that the cyclodextrin permanently in the
sol-gel matrix is ??anchored.
According to a preferred embodiment, the coating is
characterized in that the sol-gel matrix in the cyclodextrin
molecules subsequently incorporated 0.1 weight -% of organic
substances are stored - up to 10% by weight.
According to a preferred embodiment, the coating is
characterized in that the sol-gel matrix in the cyclodextrin
molecules subsequently incorporated 0.1 weight - up to 10%
by weight-% Insecticides, fungicides and / or biostatic and
biocidal substances are stored.
According to a preferred embodiment, the coating is
characterized in that the carrier material is a textile
material, a nonwoven fabric made of natural or synthetic
polymers or mixtures of these polymers.
According to a preferred embodiment, the coating is
characterized in that the carrier material consists of
inorganic substances.
According to a preferred embodiment, the coating is
characterized in that the carrier material contains glass
fibers, carbon fibers and / or ceramic fibers. According to
a preferred embodiment, the coating is characterized in that
the carrier material includes metal, ceramic, glass-like and
/ or cellulosic materials.
According to a preferred embodiment, the coating is
characterized in that the carrier material, wood and / or
wood chip plant substances.
According to a preferred embodiment, the coating is
characterized in that the carrier material has a surface of
plastics or plastic-like materials.
According to a preferred embodiment, the coating wherein the
coating has a thickness of 1 x 10 <"6> m to 50 x 10
<"> ^ m (very thin) or a thickness of 100 x 10
<"6> m to 1000 x 10 <"6> m (thin) has.
The cyclodextrin-salt can be applied to metallic and ceramic
surfaces by a dipping or spraying.After drying at room
temperature, a thin layer has formed on the surface that is
mechanically stable against external influences.
The cyclodextrin-salt are also used for impregnation of
porous inorganic materials. By immersion of these materials
into suitable brine they reach into all the pores by
capillary forces. After centrifugation, excess sol is
removed from the pores.After drying at room temperature, the
surfaces of the pores are coated by the sol, the pores of
the material has been preserved. The coating is permanent.
Natural materials such as wood and paper can be impregnated
by dipping into the corresponding cyclodextrin-Sole. In this
cause the brine one hydrophobicisation the surface. In
addition, the cyclodextrins can be chemical agents against
pests are stored.This leads to an improved wood
preservation. In the manufacture of wood particle materials
of different sizes of wood chips with a binder are pressed
together. After manufacture the fittings by dipping or
spraying with a cyclodextrin-salt impregnated. This causes a
hydrophobization the surface. Simultaneously, the
cyclodextrin molecules capable of chemical components that
can be released from the binders are too complex.Thus, the
emission of substances that can cause an odor nuisance is
reduced considerably.
Insulation, made from mineral or natural fiber materials can
be impregnated by immersion in a brine cyclodextrin. After
drying, the cyclodextrin cavities with organic substances
such as insecticides and fungicides are loaded.The coating
with the sol, the combustibility of the insulating material
is reduced from natural fiber materials. The loading of the
cyclodextrins with insecticides and / or fungicides reduce
the pest infestation and / or infestation by fungi. Another
advantage is that vaporize at high temperatures, the active
ingredients are not from the cyclodextrin cavities, since
the formed cyclodextrin complexes are thermally stable.This
ensures that occurs does not pollute the air by these
substances.
Flexible materials such as films, nonwovens and textile
fabrics, can be fitted by spraying or by dipping process
with the cyclodextrin-sols. Depending on the amount of the
sol is applied to the flexible structure of the material
received. The sol in fixed cyclodextrins are able to store
chemical substances from the air. They may also, by
spraying, egwith perfumes and other fragrances that are
loaded. A load of other organic substances such as
insecticides, fungicides, bactericide or biostatically
acting substances or pharmaceutical active substances is
possible. By deposition of such insecticides and fungicides,
a parasitic infestation of the materials is prevented.
After the finishing of nonwovens and / or textile fabrics
with cyclodextrins, the cyclodextrin-sols with
pharmaceutical and / or cosmetic active ingredients are
loaded. Come such a finished textile materials in contact
with human skin, so the stored substances are released by
the moisture on the skin surface of the skin.The sol-gel
coating prevents their hydrophobic properties, the growth of
skin cells, if such fabrics are used as wound dressings. By
the release of substances that have been stored in the
cyclodextrins, the healing process of wounds is accelerated.
By the incorporation of cyclodextrin into a sol-gel coating
ensures that the cyclodextrins can not be removed by washing
processes or similar processes from the surface of the
treated materials. It is therefore considered a permanent
modification of the surface of the corresponding materials.
The invention further relates to the use of a
cyclodextrin-brine as equipment / impregnation of support
materials.
This invention concerns such as the use of a sol-gel method
for the cyclodextrin-produced brine containing 0.1 to 10 wt
-% containing a cyclodextrin derivative that is dissolved or
dispersed in the sol according to the type as described
above equipment / impregnation of inorganic or organic
support materials.
The present invention is explained by examples.
Example 1
To a mixture of 50 ml of tetraethoxysilane, 15 ml of
3-glycidoxypropyltrimethoxysilane and 40 ml of ethanol are
added 10 ml of 0.01 N HCl and stirred at room temperature
for 10 hours. Then 20 ml of a 10 wt -% solution added to the
polyvinylaminsubstituierten cyclodextrin and stirred an
additional hour. The result is a water-clear sol. To this
sol, a 10 wt -% solution of H2O ZrOCI2 x 8 in 50 weight -%
ethanol added.This sol is applied to a polypropylene film
and dried at room temperature. By applying a drop of an
alkaline phenolphthalein solution on the surface, the
accessibility of the cavity of ss-cyclodextrin can be
detected. They observed a discoloration of the drop, which
occurs only in the presence of cyclodextrin (K. Beermann,
H.-J. Buschmann, D. Knittel, E. Schollmeyer, methods of
determination of cyclodextrins in textile materials, textile
finishing, 37 (2002) 17).
Example 2
To a mixture of 30 ml of tetraethoxysilane, diethoxysilane
dimethyl-30 ml, 20 ml of 3 -
glycidyloxypropyltrimethoxysilane, 60 ml of ethanol are
added dropwise 15 ml of 0.01 N HCl in 50 ml ethanol and
stirred at room temperature for 10 hours. Then 20 ml of a 15
wt -% solution added to the polyethyleniminsubstituierten
cyclodextrin and stirred an additional hour. The result is a
water-clear sol. To this sol, a solution of 10 weight -% AI2
(OH) 5ci x 2-3 H2O in 90 wt- Added% ethanol. The resulting
sol is using a padding applied to a wool fabric (wet pickup
80 weight -%) and the tissue dried at room temperature.
The proof of the accessibility of the cyclodextrin cavities
is carried out using an alkaline phenolphthalein.
Example 3
To a mixture of 70 ml of tetraethoxysilane, 30 ml of methyl
triethoxysilane, 400 ml of ethanol are added 20 ml of 0.01 N
HCl in portions and [deg.] Stirred at 25 C for several
hours.To this sol, then a solution of 10 wt% Al 2 (OH) 5ci x
2-3 H2O in 80 wt% ethanol and 30 ml of an aqueous dispersion
(20 wt -%) added to the aminosiloxansubstituierten
cyclodextrin. The resulting dispersion is applied to a
cotton fabric using a sprayer and then [deg.] At 30 C dried.
The proof of the accessibility of the cyclodextrin cavities
is carried out using an alkaline phenolphthalein.Example 4
To a mixture of 50 ml of tetraethoxysilane, 15 ml of
3-glycidoxypropyltrimethoxysilane and 40 ml of ethanol are
added 10 ml of 0.01 N HCl and stirred at room temperature
(20 <0> C) for 10 hours. Then 20 ml of a 10 wt -%
solution added to the polyvinylaminsubstituierten
cyclodextrin and stirred an additional hour. The result is a
water-clear sol. To this sol, a 10 wt -% solution of H2O
ZrOCI2 x 8 in 50 weight -% ethanol added.The resulting sol
is using a padding applied to a cotton fabric (wet pickup 80
weight -%) and the fabric is dried at room temperature.
The cotton fabric is coated with the Formazantests (mp
Altman Prog Histochem Cytochem 9 (1976;.. W. Oppermann, R.
Gutmann, S. Schmitt, E.-held hair dryer, textile finishing,
37, 19 (2003)) on his biostatic / biocidal efficacy
investigated. The efficacy is 99%, iethere is no metabolism
by microorganisms in the tissue determined.
Example 5
From the fitted cotton fabric in Example 4 is a 2 x 2 cm
<2> large piece in a petri dish on a given nutrient
agar standardization. After the inoculation, with half a
milliliter of E. coli culture is a storage of the sample at
37 [deg.] C for 24 hours. A visual inspection shows that no
growth of microorganisms on the finished textile sample has
taken place.It has formed around the sample and no yard.
This shows that the cyclodextrin biostatic not diffused out
of the sol-gel matrix.
Example 6
From the fully equipped in Example 4 is a round piece of
cotton fabric with a diameter of 5 cm placed on a watch
glass and placed in a desiccator. In the desiccator is a
petri dish with approximately 20 ml
benzyldimethylamine.After 7 days, the textile sample is
released some time in order to remove adsorbed
benzyldimethylamine, and then into a sample vial for
headspace gas chromatography transferred. After the addition
of a few microliters of water, the sample is at 80 [deg.] C
water bath. Subsequently, the gas is analyzed by gas
chromatography. The benzyldimethylamine can be clearly
demonstrated.
Example 7
From the fully equipped in Example 4 is a round piece of
cotton fabric with a diameter of 5 cm placed on a watch
glass and placed in a desiccator. In the desiccator is a
petri dish with approximately 20 ml of hexanal. After 3
days, the textile sample is released some time in order to
remove adsorbed hexanal, and then into a sample vial for
headspace gas chromatography transferred. After the addition
of a few microliters of water sample at 80 [deg is.] C water
bath. Subsequently, the gas is analyzed by gas
chromatography. The hexanal can be clearly demonstrated.
Example 8
From the fully equipped in Example 6 is a round piece of
cotton fabric with a diameter of 5 cm placed on a watch
glass and placed in a desiccator. In the desiccator is a
petri dish with approximately 20 ml benzyldimethylamine.
After 5 days of the textile sample is released some time in
order to remove adsorbed benzyldimethylamine.It is given a 2
x 2 cm <2> large piece in a petri dish on a standard 1
nutrient agar. After the inoculation, with half a milliliter
of E. coli culture is a storage of the sample at 37 [deg.] C
for 24 hours. A visual inspection shows that no growth of
microorganisms on the finished textile sample has taken
place. However, over the textile sample formed a courtyard,
in which there are no microorganisms.By the existing water
obviously a release of benzyldimethylamine has taken place.
Example 9
Of the vessel equipped in Example 2 is a circular piece of
wool fabric with a diameter of 5 cm placed on a watch glass
and placed in a desiccator. In the desiccator is a petri
dish containing about 5 ml of lemongrass oil. After 2 days
the textile sample is released some time in order to remove
adsorbed Lemon grass oil.After a slight moistening
significantly, the smell of lemon grass can be perceived.
Example 10
From the fitted wool fabric in Example 2 is a round piece
with a diameter of 5 cm placed on a watch glass and placed
in a desiccator. In the desiccator is a petri dish
containing about 5 ml of lavender oil. After 2 days the
textile sample is released some time to adsorbed lavender
oil. to remove.After a slight moistening of the smell of
lavender can clearly be seen.
Example 11
To a mixture of 30 ml of tetraethoxysilane, diethoxysilane
dimethyl-30 ml, 20 ml of 3 -
glycidyloxypropyltrimethoxysilane, 60 ml of ethanol are
added dropwise 15 ml of 0.01 N HCl in 50 ml of ethanol and
at room temperature (20 <0> C) 10 hours stirred. Then
20 ml of a 15 wt -% solution added to the partially
methylated ss-cyclodextrin and stirred an additional hour.
The result is a water-clear sol.% AI2 (OH) 5ci x 2-3 H2O in
90 wt - - To this sol, a solution of 10 wt% ethanol added.
By dipping a piece of wood in the resulting sol this is
impregnated. After drying, the piece of wood at room
temperature, the sample is sprayed with a Permethrinlösung
in acetone. After drying, the wood is dipped briefly in
acetone to remove adsorbed permethrin.Evidence of complex
formation of cyclodextrin with permethrin is done by an
aqueous extraction of the wood piece. In the extract
permethrin by GC-MS analysis is proven.
Example 12
The sol prepared in Example 4 is used to a piece of wood
floors (36 x 17 cm) to be sprayed. For comparative purposes,
an equally large piece of wood parquet with a 10 wt -%
solution of cyclodextrin polyvinylaminsubstituierten
sprayed.After drying, both samples dropped onto a drop of
water using a pipette. In the case of the sample sprayed
with the sol is no wetting of the surface. Contrast, one
observes a complete wetting in a short time, in the sample
with the sprayed polyvinylaminsubstituierten cyclodextrin.
The complexation of substances leached from the wood floor
is determined according to DIN ISO 16006-3.This is
quantitatively measured in a test chamber after a day the
concentration of formaldehyde in the air. It gives the
following values: a) wood flooring (untreated): 0.24 [ppm]
b) wood floor (sol with cyclodextrin): 0.07 [ppm] c)
Holparkett (only with cyclodextrin): 0.03 [ppm]
PT 1826248
CONTAINER FASTENING COATING COMPOSITION, CONTAINER
FASTENING COATING, ITS MANUFACTURE AND APPLICATION







WO 2009/074124
PROTECTIVE LAYER FOR PLANTS AND TREES, THE PRODUCTION
THEREOF AND USE THEREOF
2009-06-18
Inventor(s): SCHWINDT SASCHA [DE] +
(SCHWINDT, SASCHA)
Applicant(s): STIFTUNG NANO INNOVATIONS
[CH]; SCHWINDT SASCHA [DE] + (STIFTUNG NANO INNOVATIONS, ;
SCHWINDT, SASCHA)
Classification: - European:
A01N25/04; A01N25/34; A01N43/16
The invention relates to a method for producing a protective
layer on a surface of a plant, a protective coating for a
surface of a plant, a plant coated with this protective
layer, a composition for carrying out the process and the
production of the protective layer and uses of that
composition.
Background of the Invention
Every year the world's agriculture caused billions in damage
by plant pests such as fungi or Frassschädlinge that infect
the leaves of crops and damage. Previously, these pests were
controlled by herbicides, pesticides, according to the
directory (Federal Office for Consumer Protection and Food
Safety, as of 01.11.2007) to the areas
Herbicides to control weeds,
Insecticides against insect pests,
Fungicides to control fungal pathogens,
Rodenticides against rodents,
Nematicides against nematodes (roundworms)
Acaricides against mites / spiders,
Molluscicides against slugs,
Bactericidal against bacteria,
Agents against viroids,
Agents against viruses
Resources for the processing of Obstund Rebveredelung and
ornamental trees,
Tool for preventing wildlife damage
Means forWound closure / wound treatment,
Growth regulator,
Seeds and Propagating Material for the treatment of seed
potatoes and
Means of soil decontamination
belong. All means and substances in common is that they are
either the protected plant to encourage appropriate
defensive measures or kill the pests. The plant leaf is next
to the stem axis and the root of one of three basic
institutions of higher plants and is known as a body type
Phyllom.Leaves are lateral outgrowths of the node (nodes) of
the stem. The original functions of leaves photosynthesis
(structure of organic materials with the aid of light) and
transpiration (water evaporation, important for nutrient
uptake, and - transport). Leaves occur only in plants
sprout, that is, at fern-like plants (Pteridophyta) and seed
plants (Spermatophyta).However, they are absent in mosses
and algae, at the <"> phallus, however, may experience
leaf-like structures, but these are provided as an analogy
of the leaves. The variety of leaf shapes is enormous. In
some cases, in the course of evolution were also leaf
organs, the with the original function of the leaf, namely,
photosynthesis and transpiration, have nothing to do more:
for example, petals, leaf spines and leaf tendrils, and bud
scales.
The sheet includes the outside with a final tissue from the
epidermis, which consists of only one cell layer. The
epidermis has a waterproof layer of wax to the outside
cuticle that prevents unregulated evaporation. The cells of
the epidermis usually have no chloroplasts (the cell
components, in which photosynthesis takes place).Exceptions
are the epidermis of hygro, HeIound hydrophytes and
partially shade leaves, especially the guard of the stomata
(stomata), which always contain chloroplasts. The stomata
are the regulation of gas exchange, primarily of water
vapor. After the distribution of stomata, a distinction is
hypo-matic (stomata on the leaf base, most common form),
amphistomatische (stomata on both sides of the leaf) and
epistomatische leaves (stomata on the leaf surface,
suchExample, in floating leaves). The attachments are formed
by the epidermis hairs (trichomes) called. Are involved in
the formation and subepidermal cell layers, it is called
Emergence: Examples are spikes or glandular. When mesophyll
tissue called the Assimilation. It is usually in the
structured under the upper epidermis and palisade parenchyma
located below it spongy.The palisade parenchyma consists of
an elongated or three layers, perpendicular to the leaf
surface vertical, chloroplastenreicher cells. In the
palisade, whose main task is to photosynthesis, there are
about 80 percent of chloroplasts. The spongy parenchyma is
composed of irregularly shaped cells that form the basis of
their form large intercellular spaces. The main task of the
spongy parenchyma is to ensure the ventilation of the
parenchymatous tissue.The cells are relatively poor in
chloroplasts. The vascular bundles are often located on the
border between the upper Palisadenund spongy spongy. The
structure resembles that of the vascular bundles in the
shoot axis and is usually collateral. The vascular bundles
branch off from the shoot axis and pass by without turning
the petiole into the blade. This includes the xylem to leaf
surface, the phloem to the leaves.Large vascular bundles are
often surrounded by an endodermis, which is here called
bundle sheath. The bundle sheath controls the material
exchange between vascular bundles and mesophyll. The
vascular bundles end blindly in the mesophyll. Here, the
vascular bundles is reduced still more, that is, the first
sieve tubes become less and fall out, then remain in the
xylem only part Schraubentracheiden ending ultimately
blind.The entire leaf is usually so dense interspersed with
vascular bundles, leaf cell is that no more than seven cells
from a vascular bundle. The resulting small fields between
the vascular bundles are called areoles or intercostal
fields. The function of the vascular bundles is the delivery
transport of water and minerals into the leaves (through the
xylem) and the transport of photosynthates from the leaf
(through the phloem).
So far, no methods are known which generate as protection
against fungi and a Frassinsekten whatsoever layer on the
surface of the plant or leaf surface. So far, it was
expected to affect the physiology of a coating plant leaf
and thereby harm the plant would. A coating plant leaf as a
protective layer must therefore meet two conditions.Had a
sufficiently large translucency is required to provide the
information contained in the plant leaf chloroplasts with
radiation in the range of 320 to 700 nm. A in this
wavelength range adsorptive or reflective coating acts would
affect the energy supply of the plant cell. Inside the
chloroplasts located as plasmatic phase of the stroma.This
is interspersed with stroma thylakoid membranes
(Membraneinstülpungen), the multi-roll-like superimposed is
the Granum. This may in the membranes as a pigment
chlorophyll is now embedded in turn absorb light from the
above-mentioned wavelength range and use this energy for the
production of ADP (adenosine triphosphate) from ADP
(adenosine diphosphate) and phosphate.
The second requirement is to meet a nanoscale protective
layer must plant leaf, the orderly functioning of the
stomata. Through the stomata (Greek stoma, mouth) or
stomata, gas exchange is a plant. The stomata are usually of
two bean-shaped cells called guard-formed, which enclose an
opening, the gap. Counting the cells that surround the guard
around, add more, we speak of stomatal apparatus (stomatal
complex).The pores themselves are, strictly speaking, the
actual gap openings. Guard-are usually in the lower
epidermis of plant leaves, the grasses on both sides of the
leaf, and floating leaf plants only at the top. The gas
exchange with the surrounding air is especially important
for the supply of CO2. Carbon dioxide is absorbed by plants
through the processes of photosynthesis from the air.Thus,
the diffusion through the cell walls function optimally, it
must be as thin or permeable. Such cells evaporate but
plenty of water, land plants would wither quickly with such
leaves. About the separation of the intercellular space in
the Journal of the dry outside air through the stomata, the
plant receives control over the water loss.Through the pores
by evaporation (stomatal transpiration or evaporation)
instead, which creates a suction transported by water from
the roots to the leaves: further points are important for
the stomata. With the water are transferred from the soil
and nutrients are concentrated in the leaves.In addition,
the evaporation cools the leaves, this overheating in bright
sunshine and not the specific temperature optimum, the
enzymes in the leaf tissues, are not exceeded....