U.S. patent application number 12/439118 was filed with the patent office on 2010-01-07 for paper product and method for production thereof and use thereof.
This patent application is currently assigned to FRAUNHOFER-GESELLSCHAFT ZUR FORDERUNG DER ANGEWANDTEN FORSCHUNG e.V.. Invention is credited to Stephan Eichhorn, Andre Laschewsky, Siegfried Stapel, Joachim Storsberg.
Application Number | 20100000694 12/439118 |
Document ID | / |
Family ID | 38724582 |
Filed Date | 2010-01-07 |
United States Patent
Application |
20100000694 |
Kind Code |
A1 |
Storsberg; Joachim ; et
al. |
January 7, 2010 |
PAPER PRODUCT AND METHOD FOR PRODUCTION THEREOF AND USE THEREOF
Abstract
The invention relates to a method for the production of flat
paper products with increased relative wet tensile strength and
softness from a pulp suspension in which a block copolymer is added
to the pulp suspension and/or the paper product is treated during
production thereof or subsequently with the block copolymer. The
invention likewise relates to a paper product produced in this
manner. Paper products of this type are used in particular as
tissue products.
Inventors: |
Storsberg; Joachim;
(Woerrstadt, DE) ; Laschewsky; Andre; (Potsdam,
DE) ; Eichhorn; Stephan; (Gernsheim, DE) ;
Stapel; Siegfried; (Mannheim, DE) |
Correspondence
Address: |
LEYDIG VOIT & MAYER, LTD
TWO PRUDENTIAL PLAZA, SUITE 4900, 180 NORTH STETSON AVENUE
CHICAGO
IL
60601-6731
US
|
Assignee: |
FRAUNHOFER-GESELLSCHAFT ZUR
FORDERUNG DER ANGEWANDTEN FORSCHUNG e.V.
Munchen
DE
SCA HYGIENE PRODUCTS GMBH
Mannheim
DE
|
Family ID: |
38724582 |
Appl. No.: |
12/439118 |
Filed: |
July 30, 2007 |
PCT Filed: |
July 30, 2007 |
PCT NO: |
PCT/EP2007/006729 |
371 Date: |
June 16, 2009 |
Current U.S.
Class: |
162/164.3 ;
162/164.6; 162/164.7 |
Current CPC
Class: |
C09D 153/00 20130101;
C09D 153/005 20130101; C09D 151/006 20130101; C08L 51/006 20130101;
C08L 53/00 20130101; C08L 2666/02 20130101; D21H 17/46 20130101;
C08L 2666/02 20130101; C08L 2666/02 20130101; C08L 53/005 20130101;
C08L 2666/02 20130101; C08L 53/005 20130101; C08L 51/006 20130101;
C09D 151/006 20130101; C08L 53/00 20130101; C09D 153/005 20130101;
D21H 21/20 20130101; C09D 153/00 20130101; C08L 2666/02 20130101;
C08L 2666/02 20130101 |
Class at
Publication: |
162/164.3 ;
162/164.7; 162/164.6 |
International
Class: |
D21H 17/52 20060101
D21H017/52; D21H 17/53 20060101 D21H017/53; D21H 17/54 20060101
D21H017/54 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 31, 2006 |
DE |
10 2006 040 771.7 |
Claims
1. A method for the production of flat paper products with
increased relative wet tensile strength and softness from a pulp
suspension in which a block copolymer with the blocks A and B is
added to the pulp suspension and/or the paper product is treated
during production thereof or subsequently with the block copolymer,
wherein A is a segment with at least one connectable group for
cellulose and has a weight average molecular weight in the range of
300 to 3,000,000 g/mol and B represents a polyalkylene glycol
segment of the general formula I ##STR00005## with n=2 to 6 and m
being chosen such that the weight average molecular weight of
segment B is in the range of 400 to 50,000 g/mol.
2. The method according to claim 1, wherein segment A is selected
from the group consisting of glycidyl, benzylhalogenide,
.alpha.-halogenacyl, isocyanate, anhydride, azide, tosylate and
mesylate.
3. The method according to claim 1, wherein segment A is selected
from the group consisting of: ##STR00006## with p=1 to 12, r=3 to
3,000, R.sub.1=H or CH.sub.3 and R.sub.2=halogen, tosylate or
mesylate, R.sub.3=H, if R.sub.1=CH.sub.3 and R.sub.3=CH.sub.3, if
R.sub.1=H and also X=O or NR.sub.4 with R.sub.4=H or CH.sub.3.
4. The method according to claim 1, wherein segment A is formed
from a monomer of the general formula II ##STR00007## with
R.sub.1=H.
5. The method according to claim 1, wherein segment A is formed
from a monomer of the general formula II, ##STR00008## with
R.sub.1=H or CH.sub.3, together with at least one further radically
polymerisable comonomer selected from the group consisting of
aliphatic and aromatic methacrylic acid esters, aliphatic and
aromatic acrylamides and styrene which can also be substituted with
NR.sub.5, OR.sub.5 and/or COOR.sub.5 with R.sub.5=C.sub.1-C.sub.12
alkyl or aryl.
6. The method according to claim 1, wherein the weight average
molecular weight of segment A is in the range of 1,000 to 1,000,000
g/mol.
7. The method according to claim 1, wherein the weight average
molecular weight of segment B is in the range of 400 to 10,000
g/mol.
8. The method according to claim 1, wherein the block copolymer is
in addition coupled to a polymer amine.
9. The method according to claim 8, wherein the block copolymer is
coupled in addition to a polyethylene imine segment of the general
formula III with formation of a graft copolymer, ##STR00009## x, y
and z being chosen such that the weight average molecular weight is
in the range of 500 to 3,000,000 g/mol.
10. The method according to claim 8, wherein the block copolymer is
coupled in addition to poly-4-vinylpyridine.
11. The method according to claim 8, wherein the graft copolymer
has a backbone made of the polymer amine and grafts made of the
block copolymer.
12. The method according to claim 8, wherein the graft copolymer
has a backbone made of the block copolymer and grafts made of the
polymer amine.
13. The method according to claim 1, wherein polyethylene glycol is
used as polyalkylene glycol.
14. The method according to claim 1, wherein a free glycidyl
function of the polyalkylene glycol is coupled via the amine groups
to the polyethylene imine.
15. A paper product with increased relative wet tensile strength
and softness which contains cellulose fibres which are crosslinked
with a block copolymer with the blocks A and B, wherein A is a
segment with at least one connectable group for cellulose and has a
weight average molecular weight in the range of 300 to 3,000,000
g/mol and B represents a polyalkylene glycol segment of the general
formula I ##STR00010## n being chosen such that the weight average
molecular weight of segment B is in the range of 400 to 50,000
g/mol.
16. The paper product according to claim 15, wherein segment A is
selected from the group consisting of glycidyl, benzylhalogenide,
.alpha.-halogenacyl, isocyanate, anhydride, azide, tosylate and
mesylate.
17. The paper product according to claim 15, wherein segment A is
selected from the group consisting of ##STR00011## with p=1 to 12,
r=3 to 3,000, R.sub.1=H or CH.sub.3 and R.sub.2=halogen, tosylate
or mesylate, R.sub.3=H, if R.sub.1=CH.sub.3 and R.sub.3=CH.sub.3,
if R.sub.1=H and also X=O or NR.sub.4 with R.sub.4=H or
CH.sub.3.
18. The paper product according to claim 15, wherein segment A is
formed from a monomer of formula II ##STR00012## with
R.sub.1=H.
19. The paper product according to claim 15, wherein segment A is
formed from a monomer of formula II ##STR00013## with R.sub.1=H or
CH.sub.3 together with at least one further radically polymerisable
comonomer selected from the group consisting of aliphatic and
aromatic methacrylic acid esters, aliphatic and aromatic
acrylamides and styrene which can also be substituted with
NR.sub.5, OR.sub.5 and/or COOR.sub.5 with R.sub.5=C.sub.1-C.sub.12
alkyl or aryl.
20. The paper product according to claim 15, wherein the weight
average molecular weight of segment A is in the range of 1,000 to
1,000,000 g/mol.
21. The paper product according to claim 15, wherein the weight
average molecular weight of segment B is in the range of 400 to
10,000 g/mol.
22. The paper product according to claim 15, wherein the block
copolymer is in addition coupled to a polymer amine.
23. The paper product according to claim 22, wherein the block
copolymer is coupled in addition to a polyethylene imine segment of
the general formula III with formation of a graft copolymer,
##STR00014## x, y and z being chosen such that the weight average
molecular weight is in the range of 500 to 3,000,000 g/mol.
24. The paper product according to claim 22, wherein the block
copolymer is coupled in addition to poly-4-vinylpyridine.
25. The paper product according to claim 22, wherein the graft
copolymer has a backbone made of polyethylene imine and grafts made
of the block copolymer.
26. The paper product according to claim 22, wherein the graft
copolymer has a backbone made of the block copolymer and grafts
made of the polyethylene imine.
27. The paper product according to claim 22, wherein the
polyethylene imine is linear.
28. The paper product according to claim 22, wherein the
polyethylene imine is branched.
29. The paper product according to claim 15, wherein the
polyalkylene glycol is polyethylene glycol.
30. The paper product according to claim 15, wherein a free
glycidyl function of the polyalkylene glycol is coupled via the
amine groups to the polyethylene imine.
31. The paper product according to claim 15 which is a tissue
product.
Description
[0001] The invention relates to a method for the production of flat
paper products with increased relative wet tensile strength and
softness from a pulp suspension in which a block copolymer is added
to the pulp suspension and/or the paper product is treated during
production thereof or subsequently with the block copolymer. The
invention likewise relates to a paper product produced in this
manner. Paper products of this type are used in particular as
tissue products.
[0002] The cellulose fibres used in paper production are negatively
charged. For a simple and economical paper production method known
to the person skilled in the art, it is most favourable if
treatment chemicals, e.g. wet-strength agents, are metered directly
into the aqueous pulp suspension (pulp) with which then the paper
is produced. The technical tissue production process is explained
subsequently in brief. The aqueous cellulose pulp is then placed on
the machine wires in the technical process, formed there and
partially dewatered and subsequently passes into the drying part of
the tissue machine. The so-called Yankee cylinder has a surface
temperature of approx. 140.degree. C., above that there is gas
drying with hood temperatures around approx. 450.degree. C. During
an extremely short contact time of a few milliseconds on the
cylinder, the curing process of the wet-strength agents begins,
said process being terminated during the subsequent storage of the
finished tissue web (so-called "subsequent ripening").
[0003] Since the cellulose fibres used in paper production are
negatively charged, a potential wet-strength agent must be cationic
(positively charged) and water-soluble or water-dispersible in
order that it can adhere to the cellulose fibre in the aqueous pulp
medium during application. The use of conventional wet-strength
agents which are based on epichlorohydrin or on polyacrylamide in
the paper or tissue industry is regarded as the present state of
the art and science. These wet-strength agents are normally added,
in the case of household tissues, in quantities of 8 to 10
kg/tonne. The cellulose fibres of the paper or tissue hold together
in the dry state in the network of a sheet by means of fibre-fibre
contact points which are based on van der Waals' or hydrogen bonds.
These bonds are very water-sensitive, i.e. the wetter the tissue
becomes the looser these bonds become. In order now to be able to
produce so-called wet-strength papers, such as e.g. kitchen or
household towels or other toilet tissues, wet-strength agents are
added which have the task of forming bonds which are resistant at
least temporarily to water. According to the present state of the
art, various chemically-based polymer wet-strength agents are
available in paper or tissue production, which are described for
example in "Papermaking Chemistry" (book 4, ISBN: 9789525216042,
Editor: Leo Neimo, published in cooperation with the Finnish Paper
Engineers' Association and TAPPI, pp. 288-301). There are used
predominantly melamine formaldehyde resins (MF), as described for
example in U.S. Pat. No. 4,461,858, and cationic polymers based on
polyamide-epichlorohydrin and polyamidine-epichlorohydrin (PAE), as
described for example in U.S. Pat. No. 2,926,116, U.S. Pat. No.
2,926,154, U.S. Pat. No. 3,733,290, U.S. Pat. No. 4,566,943, U.S.
Pat. No. 4,605,702.
[0004] It is disadvantageous with the above-mentioned wet-strength
agents, on the one hand, that the treated tissue does in fact have
increased wet strength but this has the consequence of reduced
softness. This must then be achieved by an additional mechanical
treatment of the tissue. A further disadvantage of PAEs is the
production-related content of organic halogen compounds. WO
00/40639 describes a PAE-based wet-strength agent with a
low-content of organically bonded chlorine. Furthermore,
water-dispersible wet-strength agents based on polyisocyanate are
described in DE 196 40 205 A1, which are obtained by conversion of
the initial components polyisocyanate, polyalkyleneoxide polyether
alcohol of a quaternised aminopolyalkyleneoxide polyether alcohol
and also possibly further aids and supplements.
[0005] Furthermore, it is known from DE 698 14 359 T2 that e.g.
polyethylene imine belongs to the temporary wet-strength agents.
Furthermore it is known to the person skilled in the art that
polymers which have a low glass-transition point (room temperature
or below) have soft properties. DE 689 16 860 describes in detail a
method for the production of absorbent structures in which the
absorbing structures are produced from mixed paper raw materials,
one of which is treated with a latex with an elastomer core. The
softness is hereby achieved by the soft rubber latex. In order that
the lattices adhere to the cellulose fibre in the wet method, these
have a polymer shell based on oleyl-polyethoxylate which carries a
quaternary functional (trimethyl)-ammonium group at the terminal
end of the ethoxylate chain. However it is disadvantageous with
this method that the soft lattices are of a hydrophobic
(=water-repellent) nature and hence negatively affect the
absorption power of the paper produced therefrom in the case of a
single "one batch" application. Therefore the operation must take
place with this method with different pulps, only one being treated
with the latex. In a further step, the pulp suspension treated with
latex is mixed with an untreated pulp in order thus to achieve the
water-absorbent effect of the paper. WO 96/333 10 describes a
method for the production of soft-creped tissue which is obtained
by a specially controlled production process, mainly by mechanical
treatment.
[0006] Starting herefrom, it was the object of the present
invention to overcome the problems known from the state of the art.
It was therefore an aim to increase the wet strength of paper
products without having to accept negative effects on the softness
of the products. Likewise the absorbability of the paper product
should not be negatively influenced. A further object of the
present invention resided in making possible an application which
is as simple as possible of the pre-treatment chemicals in the
cellulose pulp and in providing an ecologically safe treatment
chemical.
[0007] This object is achieved by the method having the features of
claim 1 and also by the paper product having the features of claim
14. The further dependent claims represent advantageous
developments. A use according to the invention is cited in claim
29.
[0008] According to the invention, a method for the production of
flat paper products with increased relative wet tensile strength
and softness from a pulp suspension is provided, in which a block
copolymer with the blocks A and B is added to the pulp suspension
and/or the paper product is treated during production thereof or
subsequently with the block copolymer. It is a particular feature
of the present invention that A is a segment with at least one
connectable group for cellulose and has a weight average molecular
weight in the range of 300 to 3,000,000 g/mol and B represents a
polyalkylene glycol segment of the general formula I
##STR00001##
with n=2 to 6 and m being chosen such that the weight average
molecular weight of segment B is in the range of 400 to 50,000
g/mol.
[0009] A simple application in the production of paper products,
ideally in the aqueous pulp suspension, requires that the polymer
systems used for the treatment are water-soluble or
water-dispersible. These requirements were able to be fulfilled by
the application of copolymer systems which are constructed from
soft segments, i.e. flexible polymer blocks with low T.sub.g, and
adhesive segments, i.e. polymer blocks with a cationic structure,
also in combination with chemically reactive groups. Adhesive
segments are required in order to achieve adhesion of the chemicals
to the charged pulp fibre, whilst the reactive segments, during the
further processing process by a chemical reaction, effect a
covalent crosslinking of the chemical with the fibre and also the
fibres to each other and hence increase the wet tensile strength of
the paper product. At the same time, the soft segment effects
elasticity between the fibres so that the increase in wet tensile
strength is not achieved at the expense of softness, as is the case
with the systems known to date from the state of the art.
[0010] Surprisingly, it was now able to be established that the
block copolymers provided according to the invention can be applied
in the simplest manner, the production thereof also being possible
in the simplest manner. The synthesis strategy resides in
converting a precursor compound which contains soft polyalkylene
glycol segments in a simple manner to form block copolymers by
copolymerisation with suitable monomers. A particularly simple
synthesis is hereby possible by the use of PEG azo initiators which
degrade thermally into polymer PEG biradicals and hence leads to
the formation of for example A-B-A block copolymers which are
particularly preferred.
[0011] The production of such macro-azo initiators (MAI) is
described for example in Takahashi et al., Journal of Polymer
Science, Part A, Polymer Chemistry, Vol. 35, 69-76 (1997) or also
in Smith "Die Makromolekulare Chemie 1003", 301-303 (1967) and
state of the art.
[0012] Segment A is selected preferably from the group consisting
of glycidyl, benzylhalogenide, .alpha.-halogenacyl, isocyanate,
anhydride, azide, tosylate and mesylate. A few representatives are
cited subsequently by way of example.
##STR00002##
with p=1 to 12, r=3 to 3,000, R.sub.1=H or CH.sub.3 and
R.sub.2=halogen, tosylate or mesylate, R.sub.3=H, if
R.sub.1=CH.sub.3 and R.sub.3=CH.sub.3, if R.sub.1=H and also X=O or
NR.sub.4 with R.sub.4=H or CH.sub.3.
[0013] As a further variant according to the invention, segment A
can be formed as a homopolymer from a monomer of the general
formula II,
##STR00003##
wherein R.sub.1=H. If R.sub.1=CH.sub.3, then the monomer of the
general formula II can be copolymerised together with at least one
further radically polymerisable comonomer selected from the group
consisting of aliphatic and aromatic methacrylic acid esters,
aliphatic and aromatic acrylamides and styrene which can also be
substituted with NR.sub.5, OR.sub.5 and/or COOR.sub.5 with
R.sub.5=C.sub.1-C.sub.12 alkyl or aryl. This is likewise possible
for R.sub.1=H. The aromatic substituent in formula II can be
disposed in ortho-, meta- or para-position.
[0014] Basically all methacrylic acid esters, acrylamides and
styrenes which are substituted with the remaining radicals, in the
case of which R.sub.5 is not hydrogen, can be used here.
[0015] The weight average molecular weight of segment A is
preferably in the range of 1,000 to 1,000,000 g/mol, whilst the
weight average molecular weight of segment B is preferably in the
range of 400 to 10,000 g/mol.
[0016] In a further preferred variant, the block copolymer can in
addition be coupled to a polymer amine, in particular a
polyethylene imine and/or a polyvinyl amine. A polyethylene segment
of the general formula III
##STR00004##
which is coupled with formation of a graft copolymer, x, y and z
being chosen such that the weight average molecular weight is in
the range of 500 to 3,000,000 g/mol, in particular 500 to 1,000,000
g/mol, is particularly preferred.
[0017] Another particularly preferred variant concerns coupling to
poly-4-vinylpyridine.
[0018] In the case of the previously described coupling to a
polymer amine, a graft copolymer is present which has a backbone
made of the polymer amine and grafts made of the block copolymer.
However, the converse variant is also possible in that the graft
copolymer comprises a backbone made of the block copolymer and
grafts made of the polymer amine.
[0019] The polyalkylene glycol is preferably polyethylene
glycol.
[0020] According to the invention, a paper product with increased
relative wet tensile strength and softness is likewise provided,
which contains cellulose fibres which are crosslinked with a block
copolymer with the blocks A and B of the previously described
structure.
[0021] Paper products of this type are used in particular as tissue
products.
[0022] The subject according to the invention is intended to be
explained in more detail with reference to the subsequent FIGURE
and examples without wishing to restrict said subject to the
special embodiments shown here.
[0023] FIG. 1 shows, with reference to a schematic representation,
the course of the production process according to the invention for
paper products.
EXAMPLE 1
Synthesis of poly(glycidyl methacrylate)-block-poly(ethylene
glycol)-block-poly(glycidyl methacrylate)
[0024] The macro-azo initiators listed in Table 1 were used.
TABLE-US-00001 TABLE 1 macro-azo molecular weight molecular weight
of mol azo group initiator [g/mol] the segment per 1 g VPE-0201
15,000-30,000 2,000 0.45 mmol/g (1/14) VPE-0401 25,000-40,000 4,000
0.24 mmol/g (1/25)
EXAMPLE 1.1
Triblock Copolymer Made of VPE-0401 and Glycidyl Methacrylate
(1:1)
[0025] Macro-azo initiator VPE-0401 [WAKO], 20 g 1,4-dioxane
[ACROS, p.a., stabilised] and subsequently 7.64 g glycidyl
methacrylate [ALDRICH, 97%] are weighed into a Schlenk flask. After
degassing with N.sub.2, the flask is sealed with a septum and the
reaction solution is brought to polymerisation with agitation on
the oil bath at 85.degree. C. overnight. After cooling to room
temperature, the product is converted with agitation into
diethylether (glycidyl methacrylate is soluble in Et.sub.2O, the
product in dioxane). The polymer is freed of the remaining solvent
in Petri dishes in the vacuum drying cabinet over P.sub.2O.sub.5.
The yield is 93% of the theoretical.
EXAMPLE 1.2
Triblock Copolymer Made of VPE-0201 and Glycidyl Methacrylate
(1:1)
[0026] 8.0 g macro-azo initiator VPE-0201 [WAKO], 20 g 1,4-dioxane
[ACROS, p.a., stabilised] and subsequently 8.0 g glycidyl
methacrylate [ALDRICH, 97%] are weighed into a Schlenk flask. After
degassing with N.sub.2, the flask is sealed with a septum and the
reaction solution is brought to polymerisation with agitation on
the oil bath at 85.degree. C. overnight. After cooling to room
temperature, the product is converted with agitation into
diethylether (glycidyl methacrylate is soluble in Et.sub.2O, the
product in dioxane). The polymer is freed of the solvent in Petri
dishes in the drying cabinet over P.sub.2O.sub.5. The yield is 93%
of the theoretical.
EXAMPLE 1.3
Production of Solutions for the Sheet Formation Tests
[0027] Production of 1% Aqueous Active Substance Dispersions
[0028] A specific quantity of polymer (see Table 2) was dissolved
in 4.5 g dioxane (material see Table 2).
[0029] 45 g water were then added to this solution with intensive
agitation. Thereafter, the corresponding quantity of polyethylene
imine (PEI) was added immediately with agitation. The dispersion
was agitated for a further 30 minutes and then was ready for
use.
[0030] The individual batches are listed in Table 2.
TABLE-US-00002 TABLE 2 OM 17 - A1 triblock copolymer 0.40 g polymer
PGLMA-PEG-PGLMA 0.1 g PEI OM 17 4.5 g dioxane OM 18 - B1 triblock
copolymer 0.40 g polymer PGLMA-PEG-PGLMA 0.1 g PEI OM 18 4.5 g
dioxane OM 17 - C1 triblock copolymer 0.35 g polymer
PGLMA-PEG-PGLMA 0.15 g PEI OM 17 4.5 g dioxane OM 18 - D1 triblock
copolymer 0.35 g polymer PGLMA-PEG-PGLMA 0.15 g PEI OM 18 4.5 g
dioxane OM 17 - E1 triblock copolymer 0.30 g polymer
PGLMA-PEG-PGLMA 0.2 g PEI OM 17 4.5 g dioxane OM 18 - F1 triblock
copolymer 0.30 g polymer PGLMA-PEG-PGLMA 0.2 g PEI OM 18 4.5 g
dioxane OM 17 - G1 triblock copolymer 0.25 g polymer
PGLMA-PEG-PGLMA 0.25 g PEI OM 17 4.5 g dioxane OM 18 - H1 triblock
copolymer 0.25 g polymer PGLMA-PEG-PGLMA 0.25 g PEI OM 18 4.5 g
dioxane
[0031] Furthermore, solutions made of PEI and Servamine were
produced for comparison.
[0032] The results are presented in Table 3.
TABLE-US-00003 TABLE 3 tensile breaking breaking basis tensile
strength length length tensile chemicals weight thickness
permeability strength (dry) (wet) (dry) (wet) wet/dry strength kg/t
pulp [g/m.sup.2] [mm] [ml/min] [N] [N] [m] [m] [%] [mNm/m] 0 79.3
0.12 1450 50.3 0.6 4311 51 1.2 1350 1.5 Servamine KZC 14 80.7 0.12
1300 49.7 5.1 4185 429 10.3 1350 1.5 Servamine KZC 20 80.3 0.12
1250 49.8 3.9 4215 330 7.8 1450 3 A: triblock copolymer OM17; 0.40
g 80.3 0.12 1600 46.6 2.3 3944 195 4.9 1300 polymer 0.10 g PEI 9 A:
triblock copolymer OM17; 0.40 g 79.7 0.12 1750 47.8 6.2 4076 529
13.0 1300 polymer 0.10 g PEI 3 B: triblock copolymer OM18; 0.40 g
79.7 0.12 1500 47.0 1.9 4008 162 4.0 1400 polymer 0.10 g PEI 9 B:
triblock copolymer OM18; 0.40 g 80.3 0.12 1700 49.1 5.5 4155 465
11.2 1350 polymer 0.15 g PEI 3 C: triblock copolymer OM17; 0.35 g
80.7 0.13 1500 47.5 3.1 4000 261 6.5 1250 polymer 0.15 g PEI 9 C:
triblock copolymer OM17; 0.35 g 80.3 0.13 1750 51.6 7.4 4367 626
14.3 1450 polymer 0.15 g PEI 3 D: triblock copolymer OM18; 0.35 g
79.3 0.12 1650 45.2 2.5 3874 214 5.5 1350 polymer 0.15 g PEI 9 D:
triblock copolymer OM18; 0.35 g 80.7 0.13 1800 52.6 6.4 4429 539
12.2 1500 polymer 0.15 g PEI 3 E: triblock copolymer OM17; 0.30 g
81.3 0.13 1400 49.5 3.4 4138 284 6.9 1400 polymer 0.20 g PEI 9 E:
triblock copolymer OM17; 0.30 g 81.0 0.12 1450 59.0 8.4 4950 705
14.2 1300 polymer 0.20 g PEI 3 F: triblock copolymer OM17; 0.30 g
80.0 0.12 1450 50.3 2.3 4273 195 4.6 1250 polymer 0.20 g PEI 9 F:
triblock copolymer OM18; 0.30 g 80.7 0.12 1550 59.5 9.5 5011 800
16.0 1350 polymer 0.20 g PEI 3 G: triblock copolymer OM17; 0.25 g
80.7 0.12 1250 49.9 3.1 4202 261 6.2 1350 polymer 0.25 g PEI 9 G:
triblock copolymer OM17; 0.25 g 81.3 0.12 1400 61.2 9.7 5116 811
15.8 1400 polymer 0.25 g PEI 3 H: triblock copolymer OM18; 0.25 g
80.7 0.12 1350 51.3 3.0 4320 253 5.8 1400 polymer 0.25 g PEI 9 H:
triblock copolymer OM18; 0.25 g 80.0 0.12 1450 59.3 10.8 5037 917
18.2 1350 polymer 0.25 g PEI 3 graft copolymer OM20 81.7 0.13 1300
48.3 1.6 4018 133 3.3 1400 (high-molecular polyethylene imine) 9
graft copolymer OM20 80.3 0.12 1350 60.6 9.2 5129 779 15.2 1300
(high-molecular polyethylene imine) 3 graft copolymer OM21 80.0
0.12 1350 54.5 2.6 4630 221 4.8 1300 (high-molecular polyethylene
imine) 9 graft copolymer OM21 79.7 0.12 1300 61.9 9.1 5278 776 14.7
1350 (high-molecular polyethylene imine)
[0033] The preparation of the solutions can also be effected for
example such that the PEI is added firstly to the polymer dioxane
solution and the latter is placed in water subsequently with
agitation or water is added to the dioxane solution with
agitation.
EXAMPLE 2
Synthesis of poly(glycidyl methacrylate)-block-poly(ethylene
glycol)-block-poly(glycidyl methacrylate)
[0034] The macro-azo initiators listed in Table 4 were used.
TABLE-US-00004 TABLE 4 macro-azo molecular weight molecular weight
of mol azo group initiator [g/mol] the segment per 1 g VPE-0201
15,000-30,000 2,000 0.45 mmol/g (1/14) VPE-0401 25,000-40,000 4,000
0.24 mmol/g (1/25)
[0035] 20% solution of triblock copolymer (poly(glycidyl
methacrylate)-block-poly(ethylene glycol)-block-poly(glycidyl
methacrylate)) in 1,4-dioxane
[0036] 280.0 g macro-azo initiator (50.0 g VPE-0401 [WAKO]+230.0 g
VPE-0201 [WAKO] are firstly mixed well and then distributed equally
to three 1 l flasks. In total 325 g glycidyl methacrylate [ALDRICH,
97%) are added to respectively one third (93.3 g). With N.sub.2
introduction, 250 ml 1,4-dioxane [ACROS, p.a., stabilised] are
added per flask.
[0037] These reaction solutions are brought to polymerisation with
agitation on the oil bath at 80.degree. C. overnight. After cooling
to room temperature, all the reaction solutions are combined and
diluted with 1,4-dioxane to 3000 g in order to obtain a 20%
solution. They are filled into 2 bottles (respectively 1.5 kg) with
information about the dry content. The dry content is determined
with drying scales [Sartorius moisture analyser] (3 h/120.degree.
C.):
[0038] solids content.sub.1=20%
[0039] solids content.sub.2=20%
[0040] Production of the Aqueous Solutions:
[0041] High-molecular polyethylene imine (PEI) (Aldrich (Best.-no.
181978, CAS [25987-06-8]) Mw .about.75,000, Mn .about.60,000, 50%
aqueous solution) was used, which was diluted with water before the
beginning of the test to a 25% solution.
EXAMPLE 2.1
Variant 1:1 (Material Copolymer for PEI)
[0042] Production of a 0.5% solution:
[0043] 1.5 kg of the approx. 20% solution are added together to 1.2
kg of a 25% aqueous PEI solution with agitation and diluted with
117.2 kg water with rapid agitation (30 min) to form a 0.5%
solution.
EXAMPLE 2.2
Variant 1:1.3
[0044] 1.3 kg of the approx. 20% solution are added together to
1.387 kg of a 25% aqueous PEI solution with agitation and diluted
with 118.68 kg water with rapid agitation (30 min) to form a 0.5%
solution.
[0045] The solutions produced under a) and b) are used immediately
and metered in within 7 h.
EXAMPLE 3
Paper Production with the Solutions Produced in Example 2.1 and
2.2.
[0046] The solutions produced in example 2.1 and 2.2 were metered
in at position X so that different active substance concentrations
per tonne of produced paper could be set. The paper production is
represented schematically in FIG. 1.
[0047] Pulp used:
[0048] Grapho Celeste TCF tissue, SCA Hygiene Products AB, Ostrand,
Sweden
[0049] Degree of beating: 13 SR unbeaten, 18 SR beaten.
[0050] Machine Parameters:
[0051] Operating width: 0.5 m
[0052] Running speed: 20 m/min
[0053] Differential speed forming wire: TAD wire: -12%
[0054] Drying method: UCTAD (uncreped through air dried)
[0055] Temperature throughflow air: approx. 100.degree. C.
[0056] The pulp is delivered in bales. The corresponding quantity
respectively of pulp sheets was removed in order to obtain a pulp
suspension with a consistency of approx. 3%. For this purpose,
approx. 44 sheets were beaten in 800 l water for 20 minutes in the
pulper. The degree of beating of the beaten suspension was 13 SR.
Subsequently, the pulp suspension was beaten with a recirculating
beating until a degree of beating of 18 SR was achieved. A flat
cone refiner was used as beating unit.
[0057] After conclusion of the beating, the pulp suspension was
diluted in the pulper 1 to a consistency of 2.4% and was
subsequently transferred into the machine chest 3. From the machine
chest, the pulp suspension is pumped into the stock level boxes 5
with a pump 4. The required quantity of pulp suspension is pumped
via a monopump 6 into the recipient vessel 7 (Fluffer, HBX-pump).
The excess proportion of stock suspension runs back into the
machine chest 3. Deposition of the fibres is prevented by the
constant movement in the machine chest 3.
[0058] The recipient vessel 7 is a small container which is
equipped with an agitator. The stock suspension is forced into the
headbox by the movement which is produced. In order to obtain good
formation, the stock suspension is diluted to a consistency of
approx. 0.5%. Backwater 8 which is formed during the dewatering in
the forming zone is used as diluting water.
[0059] Because of the high turbulences and the low consistency in
the recipient vessel, the latter was selected as metering point for
the chemicals. The dewatering of the pulp suspension is effected on
a long wire paper machine by means of wire table, foils and vacuum
boxes. From the forming wire, the paper web is transferred through
a vacuum box to the TAD wire, the TAD wire having a speed which is
less by 12%. The paper web located on the TAD wire is moved over a
throughflow drying cylinder. Here hot air at approx. 100.degree. C.
is blown through the paper web and the wire so that a final wetness
of 5% can be set when rolling up.
[0060] The thus produced raw materials can be processed on
processing lines to form single or multilayer kitchen towels.
[0061] The thereby achieved results are represented in Table 5.
TABLE-US-00005 TABLE 5 6 kg/t 6 kg/t 9 kg/t 9 kg/t number of layers
variant a variant b variant c variant d 1 1 1 1 basis weight
g/m.sup.2 22.5 21.5 22.1 21.8 thickness .mu.m 552 555 565 573
tensile strength N/m 417.5 316.7 477.5 494.3 md tensile strength cd
N/m 191.9 165.1 162.8 153.0 stretch md % 14 12 14 15 stretch cd % 5
5 5 5 tensile strength N/m 52.1 43.2 69.7 61.3 md (wet) tensile
strength N/m 24.4 21.3 24.3 24.3 cd (wet) rel. tensile % 12 14 15
12 strength md (wet) rel. tensile % 13 13 15 16 strength cd (wet)
The measuring values mentioned in the table were determined
according to the following methods: basis weight: DIN EN ISO
12625-6 thickness: DIN EN ISO 12625-3 dry tensile strength md
machine direction: DIN EN ISO 12625-4 dry tensile strength cd cross
direction: DIN EN ISO 12625-4 stretch md machine direction: DIN EN
ISO 12625-4 stretch cd cross direction: DIN EN ISO 12625-4 wet
tensile strength md machine direction: DIN EN ISO 12625-5 wet
tensile strength cd cross direction: DIN EN ISO 12625-5 relative
wet tensile strength = wet tensile strength/dry tensile
strength
* * * * *