U.S. patent application number 12/518226 was filed with the patent office on 2009-12-24 for tissue paper comprising a softening lotion.
This patent application is currently assigned to COGNIS IP MANAGEMENT GMBH. Invention is credited to Stephen Eichhorn, Rolf Kawa, Jorg Sorns, Andrea Urban.
Application Number | 20090314444 12/518226 |
Document ID | / |
Family ID | 38022829 |
Filed Date | 2009-12-24 |
United States Patent
Application |
20090314444 |
Kind Code |
A1 |
Sorns; Jorg ; et
al. |
December 24, 2009 |
Tissue Paper Comprising a Softening Lotion
Abstract
The present invention relates to a tissue paper comprising a
lotion composition, said lotion being a liquid water-in-oil
emulsion comprising (A) a hydrocarbon-based oil, (B) optionally at
least one further oil, (C) 3 to 40 weight % of at least one
non-ionic water-in-oil emulsifier, (D) 0.5 to 10 weight % of at
least one coemulsifier based on an ethylene oxide-modified
glyceride, (E) optionally 1 to 15 weight % of at least one
humectant, (F) optionally up to 10 weight % of a metal soap, and
(G) 6 to 35 weight % of water, wherein the weight % values relate
to the total weight of the lotion composition. The lotioned tissue
paper of the invention is very stable, shows excellent softness
properties and is capable of efficiently transferring lotion to the
skin of the user. Moreover, the lotion can be applied at relatively
low temperatures and does not adversely affect the whiteness degree
of the tissue paper.
Inventors: |
Sorns; Jorg; (Duesseldorf,
DE) ; Kawa; Rolf; (Monheim, DE) ; Urban;
Andrea; (Ludwigshafen, DE) ; Eichhorn; Stephen;
(Gernsheim, DE) |
Correspondence
Address: |
FOX ROTHSCHILD LLP
2000 MARKET STREET
PHILADELPHIA
PA
19103
US
|
Assignee: |
COGNIS IP MANAGEMENT GMBH
Duesseldorf
DE
|
Family ID: |
38022829 |
Appl. No.: |
12/518226 |
Filed: |
November 29, 2007 |
PCT Filed: |
November 29, 2007 |
PCT NO: |
PCT/EP07/10350 |
371 Date: |
June 8, 2009 |
Current U.S.
Class: |
162/135 ;
162/173; 162/179 |
Current CPC
Class: |
A61K 8/064 20130101;
A61K 8/85 20130101; D21H 21/22 20130101; A61Q 19/00 20130101; D21H
17/60 20130101; A61K 8/608 20130101; A61K 8/06 20130101; A61K 8/31
20130101; D21H 27/002 20130101; D21H 17/36 20130101; A61K 8/0208
20130101 |
Class at
Publication: |
162/135 ;
162/173; 162/179 |
International
Class: |
D21H 21/00 20060101
D21H021/00; D21H 19/00 20060101 D21H019/00 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 8, 2006 |
EP |
06025407 |
Claims
1. A tissue paper comprising a lotion composition, said lotion
composition being a W/O emulsion comprising: (A) a
hydrocarbon-based oil, (B) optionally at least one further oil, (C)
3 to 40 weight % of at least one non-ionic W/O emulsifier, (D) 0.5
to 10 weight % of at least one coemulsifier based on an ethylene
oxide-modified glyceride, (E) optionally 1 to 15 weight % of at
least one humectant, (F) optionally up to 10 weight % of a metal
soap (G) 6 to 35 weight % of water, wherein the weight % is based
on the lotion composition.
2. The tissue paper according to claim 1, wherein said oil
component (A) comprises mineral oil.
3. The tissue paper according to claim 1, wherein said lotion
composition comprises at least one oil (B) having a viscosity of
about 1 to about 100 mPas measured with a Hoppler falling sphere
viscosimeter at 20.degree. C. (method DGF C-IV 7).
4. The tissue paper according to claim 1, wherein said oil
component (B) is selected from the group consisting of liquid
synthetic triglyceride mixtures; vegetable oils; guerbet alcohols;
liquid esters; liquid substituted cyclohexanes; symmetric or
asymmetric dialk(en)ylethers having from 6 to 22 carbon atoms per
alk(en)yl group; linear or branched dialk(en)ylcarbonates derived
from C6 to C22 fatty alcohols; ring-opening products of epoxidized
fatty acid esters and polyols; and silicone oils.
5. The tissue paper according to claim 1, wherein said non-ionic
emulsifier (C) comprises a liquid polyol polyester wherein a
polyhydric alcohol having at least two hydroxy groups is esterified
with at least one acid having from 6 to 30 carbon atoms.
6. The tissue paper according to claim 5, wherein said polyol
polyester comprises polyglycerin-2-dipolyhydroxystearate.
7. The tissue paper according to claim 1, wherein the glyceride
component of coemulsifier (D) comprises a hydroxy-fatty acid.
8. The tissue paper according to claim 1, wherein said ethylene
oxide-modified glyceride is obtained by reacting 2 to 15 mol of
ethylene oxide per mol of glyceride.
9. The tissue paper according to claim 1, wherein said coemulsifier
(D) comprises ethylene oxide-modified hydrogenated castor oil.
10. The tissue paper according to claim 1, wherein said humectant
comprises glycerol.
11. A tissue paper comprising a lotion composition, wherein said
lotion composition is a water-in-oil emulsion comprising: (A) 25 to
35 weight % mineral oil, (B) 20 to 30 weight % of a further oil
component selected from the group consisting of liquid synthetic
triglyceride mixtures; vegetable oils; guerbet alcohols; liquid
esters; liquid substituted cyclohexanes; symmetric or asymmetric
dialk(en)ylethers having from 6 to 22 carbon atoms per alk(en)yl
group; linear or branched dialk(en)ylcarbonate derived from C6 to
C22 fatty alcohols; ring-opening products of epoxidized fatty acid
esters and polyols; and silicone oils; (C) 12 to 21 weight % of a
W/O emulsifier selected from liquid polyol polyester wherein a
polyhydric alcohol having at least two hydroxy groups is esterified
with at least one acid having from 6 to 30 carbon atoms, (D) 4 to 7
weight % coemulsifier based on a glyceride comprising a hydroxy
fatty acid being modified with the adduct of 2 to 15 mol ethylene
oxide, (E) optionally 1 to 10 weight % of at least one humectant,
(F) optionally 0.5 to 5 weight % of a metal soap (G) 10 to 30
weight % water, (H) optionally 0.1 to 5 weight % additives, wherein
the weight % is based on the lotion composition.
12. A process for preparing a softened tissue paper comprising
applying the lotion composition of claim 1 to a tissue paper
web.
13. The process according to claim 12, wherein said lotion
composition is applied at a temperature in the range of from about
25 to about 50.degree. C. to the tissue paper web.
14. A process for preparing a softened tissue paper, comprising
applying the lotion composition of claim 11 to a tissue paper
web.
15. The process according to claim 14, wherein said lotion
composition is applied at a temperature in the range of from about
25 to about 50.degree. C. to the tissue paper web.
Description
FIELD OF INVENTION
[0001] The invention relates to a soft lotioned tissue paper, in
particular, to a soft lotioned tissue paper having softness due to
a specific lotion composition which penetrates tissue paper.
BACKGROUND ART
[0002] Softness is an important property of tissue products such as
handkerchiefs, cosmetic wipes, toilet paper, serviettes/napkins,
not to mention hand or kitchen towels, and it describes a
characteristic tactile sensation caused by the tissue product upon
contact with the skin.
[0003] Although the term "softness" is generally comprehensible, it
is extremely difficult to define because there is no physical
method of determination and, consequently no recognized industrial
standard for the classification of different degrees of
softness.
[0004] To be able to detect softness at least semi-quantitatively,
softness is determined in practice by means of a subjective method.
To do so, a "panel test" is carried out in which several trained
test persons give a comparative opinion.
[0005] In simplified terms, softness can be subdivided into its
main characteristics, surface softness and bulk softness.
[0006] Surface softness describes the feeling perceived when e.g.
one's fingertips move lightly over the surface of the sheet of
tissue. Bulk softness is defined as the sensory impression of the
resistance to mechanical deformation that is produced by a tissue
or tissue product manually deformed by crumpling or folding and/or
by compression during the process of deformation.
[0007] One method for increasing bulk softness of tissue paper as
taught by WO 96/25557 involves [0008] a) wet-laying an aqueous
slurry containing cellulosic fibres to form a web [0009] b)
applying a water soluble polyhydroxy compound to the wet web, and
[0010] c) drying and creping the web (wet web addition method).
[0011] It is further known from U.S. Pat. No. 4,764,418 that some
humectants such as polyethylene glycol contribute to the softness
of tissue products if they are applied to a dry web.
[0012] The use of humectants, such as polyhydroxy compounds, in
highly concentrated form, as softeners however, has the
disadvantage that the humectant may, upon contact, draw too much
moisture from the skin, for instance when blowing one's nose with a
tissue handkerchief. Moreover the softening effect is not yet
satisfactory.
[0013] WO 96/24723 teaches increasing the surface softness of
tissue paper by applying discrete deposits of a water free lotion
composition containing an oil and a wax. Since however, due to its
solid consistency, the treatment composition remains on the surface
of the tissue paper, it cannot contribute to bulk softness.
Further, water-free lotion compositions based on waxy or oily
materials often feel unpleasantly greasy or oily.
[0014] Moreover, water-free lotions such as the one in WO 96/24723
often do not feel particularly pleasant to the skin which is due to
their low moisture content. This holds true also for the water-free
lotions of WO 95/35411, WO 95/35412 and WO 95/16824 which are used
for softening tissue paper, too.
[0015] WO 97/30216 discloses liquid, high water softening agents on
the basis of fatty alcohols and waxy esters.
[0016] In view of their application, these lotions are still not
fully satisfying in terms of softness and/or sensory impression,
processability and stability.
[0017] EP A 1 029 977 relates to a composition for treating paper
products, such as tissue products, comprising between 30 and 90% by
weight of oil, between 1 and 40% by weight of wax, between 1 and
30% by weight of an emulsifying agent and between 5 and 35% by
weight of water. This lotion composition is solid or semisolid at
30.degree. C. and remains primarily at the surface of the tissue
paper, although it penetrates the tissue paper somewhat more than
the solid composition of WO 96/24723.
[0018] DE 199 06 081 A1 discloses emulsions containing (a) 5 to 25%
by weight polyol poly-12-hydroxy stearate, (b) 50 to 90% by weight
waxy esters and (c) 5 to 25% by weight waxes. This document further
contains examples describing the treatment of tissue papers with
W/O emulsions as defined above containing about 20 to 25% water.
These compositions are solid or semisolid at 30.degree. C. (example
1 corresponds to lotion F of EP A 1 029 977) and show the same
penetration behaviour as described above for the lotions of EP A 1
029 977.
[0019] WO 02/056842 A2 discloses a W/O emulsion containing [0020]
a) polyol poly-12-hydroxy stearate, [0021] b) an oil component
selected from glycerides, hydrocarbons, silicon oil, dialkylether
and dialkyl carbonates, or mixtures thereof and [0022] c) 5 to 25
weight % water.
[0023] It is stated that said emulsion is soft and suitable for use
as a body care agent, as well as impregnating and brightening agent
for woven fabrics, non-woven fabrics and (tissue) paper.
[0024] WO 02/057546 A1 describes a tissue paper penetrated with a
lotion composition being a liquid, viscous W/O emulsion comprising
[0025] (A) 20 to 75 weight % of at least one oil, [0026] (B) 3 to
40 weight % of at least one non-ionic W/O emulsifier, [0027] (C)
optionally 0.5 to 10 weight % of at least one wax, [0028] (D)
optionally 1 to 15 weight % of at least one humectant, [0029] (E) 6
to 25 weight % of water.
[0030] On a concrete level, it discloses the same lotion
composition as WO 02/056842 A2 comprising 20.4 weight %
cocoglycerides, 20.4 weight % dicaprylylether, 20.4 weight %
polyglycerin-2-dipolyhydroxystearate (Dehymuls.RTM. PGPH), 4.8
weight % sorbitan sesquioleate, 3.4 weight % bees wax, 2.0 weight %
dicocoyl pentaerythrityl distearyl-citrate, 3.4 weight % aluminium
stearate and 7.0 weight % glycerol. Although the lotion described
in these WO references shows a good stability under usual
conditions, stability problems may occur if it is stored for very
long times or at higher temperatures. Further, it was noted that
the incorporation of plant extracts into this lotion causes
colouring which lowers whiteness (brightness) of tissue paper
treated with this lotion. Moreover, improvements in softness also
seem to be possible.
[0031] In view of the above, it is one object of the present
invention to provide a lotioned tissue paper that overcomes
disadvantages of prior art formulations.
[0032] It is one further object of the present invention to provide
a tissue paper treated with a lotion composition wherein that
lotion composition shows an excellent stability.
[0033] According to one further object, the present invention aims
at providing a tissue paper treated with a lotion composition
showing an excellent softness (surface and/or bulk softness).
[0034] It is one further object of the present invention to provide
a lotioned tissue paper showing a high degree of whiteness
(brightness).
[0035] It is one further object of the present invention to provide
a tissue paper treated with a lotion composition that can be
applied at relatively low temperatures.
[0036] Finally, it is one further object of the present invention
to provide a tissue paper treated with a lotion composition wherein
said lotion composition shows a suitable, in particular improved
balance of critical properties including stability, softness and/or
sensory impression, compatibility with plant extracts and
application temperature.
SUMMARY OF THE INVENTION
[0037] This technical object is solved by a tissue paper treated
with a lotion composition comprising [0038] (A) a hydrocarbon-based
oil, [0039] (B) optionally at least one further oil, [0040] (C) 3
to 40 weight % of at least one non-ionic W/O emulsifier, [0041] (D)
0.5 to 10 weight % of at least one coemulsifier based on an
ethylene oxide-modified glyceride, [0042] (E) optionally 1 to 15
weight % of at least one humectant, [0043] (F) optionally up to 10
weight % of a metal soap [0044] (G) 6 to 35 weight % of water,
wherein the weight % values relate to the total weight of the
lotion composition. This lotion is liquid at room temperature
(23.degree. C.) and pumpable at 20.degree. C. It preferably
consists essentially of the above components and up to 10 weight %
other additives, for instance those described below under item
1.8.
[0045] It was found that this lotion does not only show an
excellent softness and sensory impression, but also a surprisingly
good stability, even after storage at room temperature over a
longer period of time and/or after medium-long storage at
temperatures above room temperature. Another merit of this lotion
is excellent compatibility with plant extracts and the resulting
high whiteness (brightness) of tissue papers treated therewith.
[0046] It is preferred that a tissue paper treated with this
lotion, even if containing a plant extract, shows a decrease in
whiteness of less than 3.9%, preferably less than 3.75%, in
particular less than 3.5%, as measured according to DIN EN 12625-7,
item 7.3.2, colour (D65/10.degree.), the whiteness of unlotioned
tissue paper being 100%.
[0047] Its fairly low viscosity and good penetration behaviour can
be utilized for treating the inner plies of multi-ply tissue
papers. Surprisingly, it was found that the lotion used in the
present invention displays a viscosity minimum at preferred low
application temperatures ranging from 25 to 50.degree. C., in
particular 30 to 45.degree. C., e.g. 32 to 40.degree. C., or 32 to
38.degree. C.
[0048] Moreover, the lotion is capable of transferring active
agents to the skin of the user, if necessary.
FIGURE
[0049] FIG. 1 shows the results of two rheology measurements with
the lotion of example 1 under different conditions (t denotes the
time lapsed during heating from minimum to maximum temperature and
D is the shear rate). The upper curve achieved with the lower shear
rate of D=50 1/s clearly shows a minimum at the preferred
application temperatures.
DETAILED DESCRIPTION OF THE INVENTION
[0050] The lotioned tissue paper of the invention is typically
obtained by applying the aforementioned lotion composition to a dry
tissue web. Preferably, the residual water content of the tissue
web (without lotion) is no more than 10% by weight.
1. Lotion
[0051] By mixing and homogenizing the lotion components described
in the following, a liquid water-in-oil (W/O) emulsion is obtained
which preferably has a viscosity of less than 10,000 mPas at
23.degree. C., a value typical of semi-solid lotions (measured with
a Brookfield-RVF viscosimeter, spindle 5, 10 rpm). Preferably, the
viscosity is 500 to 5,000 mPas, more preferably 700 to 3000 mPas,
in particular 1,000 to 2,000 mPas, measured at 23.degree. C. under
the above conditions.
[0052] If measured by a rheometer, the lotion shows a viscosity
[mPas] of less than 1, in particular less than 0.8 in the
temperature range of 25 to 70.degree. C. (shear rate D=50 1/sec, CR
mode (rotation), constant heating from 25 to 70.degree. C. over 450
sec, number of measuring points 200). The measurement was conducted
with a Haake RheoStress RS1 rheometer (now available from Thermo
Electron) under the following additional conditions regarding
measurement geometry: sensor C35/2.degree. Ti, A-factor of
89090.000 Pa/Nm, M-factor of 28.650 (1/s)/(rad/s), moment of
inertia: 1.769e-06 kg m.sup.2, attenuation of 30.00 and slit width
0.105 mm. The tempering device used was TCP/P (Peltier/Plate).
[0053] Despite the low viscosity, the lotion composition is very
stable during preparation and use, and does not separate into the
water and oil phase, even at temperatures above room temperature
and/or after longer storage.
[0054] The low viscosity of the lotion is enhanced by the use of a
fairly small amount of solid components. Hereinafter, the term
"solid" or "liquid" refers to the physical state at room
temperature (23.degree. C.). Preferably, the overall content of
solid components is less than 10% by weight, in particular, less
than 5% by weight, based on the total weight of the lotion
composition.
[0055] This lotion does not require the presence of silicone oils
or quaternary amine compounds in order to attain its softening
effect, although their use is not excluded.
[0056] Hereinafter, the term "oil" is used for water-insoluble,
organic, natural and synthetic, cosmetically useful oils having
preferably a liquid (also viscous) consistency at room temperature
(23.degree. C.). Moreover, unless stated otherwise, weight % values
always relate to the total weight of the lotion composition.
1.1. Hydrocarbon-Based Oil Component (A)
[0057] The total amount of oil components in the lotion composition
is preferably 20 to 75 weight % (e.g. 30 to 70 weight %), in
particular 45 to 65 weight %.
[0058] The lotion comprises as one essential component a
hydrocarbon-based oil component (A). The oil component (A) can be
properly selected among known cosmetically useful hydrocarbon-based
oils, such as cyclic or non-cyclic, saturated or unsaturated
aliphatic or aromatic oils.
[0059] The hydrocarbon-based oil preferably has from 8 to 32, in
particular 15 to 20 carbon atoms. Examples include squalane,
squalene, paraffinic oils, isohexadecane, isoeicosane, polydecene
or dialkycyclohexane, and mineral oil, mineral oil being
preferred.
[0060] If the hydrocarbon-based oil component (A) is used as sole
oil component, it is preferred to use low viscosity embodiments
thereof. According to one preferred embodiment, the
hydrocarbon-based oil component (A) is admixed with a second oil
component (B) preferably having a lower viscosity than component
(A) (measured with a Hoppler falling sphere viscosimeter as
explained below). In this embodiment, oil component (A) is
preferably present in an amount of 20 to 40 weight %, in particular
25 to 35 weight %. The preferred viscosity difference between oils
(A) and (B) is at least 5 mPas.
[0061] Preferably, the oil component (A), or the mixture of oil
component (A) and (B) is selected such that the viscosity is 1 to
230 mPas, in particular 2 to 200 mPas, e.g. 5 to 180 mPas or 10 to
150 mPas (measured with a Hoppler falling sphere viscosimeter at
20.degree. C. (method "Deutsche Gesellschaft fur Fettchemie" DGF
C-IV 7). Preferred mineral oils can be selected from white oil
pharma 40 ("Wei.beta.ol Pharma 40"), fluid or liquid paraffin oil
("Paraffinol dunnflussig"), viscous paraffin oil ("Paraffinol
dickflussig"), paraffinum liquidum, paraffinum perliquidum or
paraffinum subliquidum.
1.2. Optional Second Oil Component (B)
[0062] The second oil component may be suitably selected from among
known oils other than hydrocarbon-based ones, e.g. among oils from
plant sources or synthetic oils. If present, oil component (B) is
preferably used in amounts of 10 to 40 weight %, in particular 20
to 30 weight %.
[0063] If present, the second oil component preferably is selected
in a suitable manner among low viscosity oils, i.e oils having a
viscosity of 1 to 100 mPas, in particular 1 to 50 mPas (e.g. 1 to
30 mPaS) measured with a Hoppler falling sphere viscosimeter at
20.degree. C. (method "Deutsche Gesellschaft fur Fettchemie" DGF
C-IV 7), in order to achieve the desired penetration behaviour on
tissue.
[0064] Preferably, the oil component (B) contains at least one oil
selected from among the following types: [0065] Glycerides, which
are mono-, di- and/or tri ester (fatty acid ester) of glycerol (in
particular di- and/or triester). Glycerides can be obtained by
chemical synthesis or from natural sources (plant or animal) as
known in the art. Preferably the fatty acid component has from 6 to
24, more preferably 6 to 18, in particular 8 to 18 carbon atoms.
The fatty acid can be branched or unbranched as well as saturated
or unsaturated. According to the invention the use of liquid
glycerides from plant sources is preferred, in particular the use
of a modified liquid coconut oil (INCI name: cocoglycerides,
available under the trade name Myritol.RTM. 331 from Cognis
Deutschland GmbH) which contains as main component a mixture of di-
and triglycerides based on C8 to C18 fatty acids. [0066] Natural
plant oils which may contain liquid glycerides as main component,
such as soja oil, peanut oil, olive oil, sunflower oil, macademia
nut oil or jojoba oil. [0067] Guerbet alcohols; guerbet alcohols
are based on fatty alcohols having 6 to 18, preferably 8 to 10
carbon atoms, such as 2-ethylhexanol or 2-octyldodecanol; [0068]
Fatty acid esters, preferably those having 12 to 60 carbon atoms
including [0069] a) esters of linear or branched, saturated or
unsaturated C.sub.6-C.sub.24 fatty acids and linear or branched,
saturated or unsaturated C.sub.6-C.sub.24 fatty alcohols (e.g.
hexyl laurate, myristyl isostearate, myristyl oleate, cetyl
isostearate, cetyl oleate, stearyl isostearate, stearyl oleate,
isostearyl myristate, isostearyl palmitate, isostearyl stearate,
isostearyliso stearate, isostearyl oleate, oleyl myristate, oleyl
isostearate, oleyl oleate, oleyl erucate, erucyl isostearate,
erucyl oleate, cococaprylate/caprate). [0070] b) Esters of
C.sub.18-C.sub.38 alkyl hydroxy carboxylic acids and linear or
branched, saturated or unsaturated C.sub.6-C.sub.22 fatty alcohols,
[0071] c) esters of linear and/or branched, saturated or
unsaturated fatty acids and polyhydric alcohols (such as propylene
glycol, dimerdiol or trimertriole) and/or guerbet alcohols, liquid
triglycerides or triglyceride mixtures, or liquid
mono-/di-triglyceride mixtures. [0072] Esters from aromatic
carboxylic acids, such as esters of C.sub.6-C.sub.22 fatty alcohols
and/or guerbet alcohols and aromatic carboxylic acids, in
particular benzoic acid (e.g. Finsolv.RTM.), [0073] Esters of
dicarboxylic acids, in particular esters of C.sub.2-C.sub.12
dicarboxylic acids and linear or branched, saturated or unsaturated
alcohols having 1 to 22 carbon atoms or polyols having 2 to 10
carbon atoms and 2 to 6 hydroxy groups. [0074] Substituted
cyclohexanes [0075] Symmetric or asymmetric, linear or branched
dialk(en)ylethers having from 6 to 24 carbon atoms (per alk(en)yl
group, preferably having 12 to 24 C atoms as total number of C
atoms), such as di-n-octylether (dicaprylylether),
di-(2-ethylhexy)ether, laurylmethylether, octylbutylether or
didocecylether, the use of di-n-octylether (dicaprylylether;
viscosity: 2-5 mPaS at 20.degree. C.; DGF method described above)
being preferred.
[0076] Dialk(en)ylcarbonates having preferably at least one C6 to
22 alkyl or alkenyl group (preferred total number of C atoms: not
more than 45, including the C atom of the carbonate unit). The
alkyl or alkenyl group can be straight or branched. The alkenyl
unit may display more than one double bond. They can be obtained by
transesterification of dimethyl or diethyl carbonate in the
presence of C6 to C22 fatty alcohols according to known methods
(cf. Chem. Rev. 96, 951 (1996)). Typical examples for
dialk(en)ylcarbonates are the (partial) transesterification
products of caprone alcohol, capryl alcohol, 2-ethylhexanol,
n-decanol, lauryl alcohol, isotridecyl alcohol, myristyl alcohol,
cetyl alcohol, palmoleyl alcohol, stearyl alcohol, isostearyl
alcohol, oleyl alcohol, elaidyl alcohol, petroselinyl alcohol,
linolyl alcohol, linolenyl alcohol, elaeostearyl alcohol, arachidyl
alcohol, gadoleyl alcohol, behenyl alcohol, erucyl alcohol and
brassidyl alcohol as well as their technical mixture, which are for
instance obtained by high pressure hydrogenisation of technical
methyl ester(s) on fat or oil basis. Particularly suitable in view
of their low viscosity at 20.degree. C. are dihexyl-, dioctyl-,
di-(2-ethylhexyl)- or dioleylcarbonate (viscosity of
dioctylcarbonate: 7 mPaS at 20.degree. C.; DGF method described
above). Thus it is preferred to use either short chain (C6 to C10)
alkyl or alkenyl carbonates. [0077] Ring-opening products of
epoxidized fatty acid esters and polyols, and [0078] silicon oils
of linear or cyclic structure such as dimethylpolysiloxane,
methylphenylpolysiloxane, cyclomethicone, as well as amino-, fatty
acid-, alcohol-, polyether-, epoxy-, fluorine-, glycosyde and/or
alkyl-modified silicon oil. Further, dimethicone oils can be
used.
[0079] Generally, it is preferred to select the liquid embodiments
among the above compound types.
[0080] Further, the oil component (B) is preferably selected
(depending on chain length or esterification degree as known from
the prior art) such that its polarity is not greater than 5, in
particular not greater than 4 Debey.
[0081] Oil component (B) is preferably selected from oils having
spreading values of at least 250 mm.sup.2/10 min (measured in line
with U. Zeidler: Uber das Spreiten von Lipiden auf der Haut,
Fette-Seifen-Anstrichmittel Nr. 10, 403-408, 1985). It is
particularly preferred to use ester oils, ether oils, carbonate
oils, guerbet alcohols or glycerides having the above spreading
value. These include for instance dibutyl adipate, isopropyl
palmitate, hexyl laurate, ethylhexyl stearate, dicaprylyl ether,
dicaprylyl carbonate, hexyldecyl stearate, oleyl oleate, oleyl
erucate or vegetable oils.
[0082] The weight proportion of oil component (B) is preferably at
least 20% by weight, in particular at least 40% by weight based on
the total amount of (A) and (B).
1.3. W/O Emulsifier (C)
[0083] The emulsifier or emulsifier composition (C) is of a
non-ionic type and has primarily the function of forming a
water-in-oil emulsion. It can also contribute to the softness of
tissue paper. Preferably, it has a HLB value of 2.5 to 10, in
particular 2.5 to 5.
[0084] Its content is 3 to 40% by weight, more preferably 8 to 30
(e.g. 10 to 25), in particular 12 to 21% by weight.
[0085] Preferably a liquid W/O emulsifier is used, although the use
of minor amounts of a solid emulsifier is possible, as long as the
viscosity of the resulting lotion composition is not too high.
[0086] Component (C) can be suitably selected from a liquid polyol
polyester wherein a polyol having at least two hydroxy groups is
esterified with at least one carboxylic acid having from 6 to 30
carbon atoms. Polyols include monosaccharides, disaccharides, and
trisaccharides, sugar alcohols, other sugar derivatives, glycerol,
and polyglycerols, e.g. diglycerol, triglycerol, and higher
glycerols. Such polyol preferably has from 3 to 12, in particular 3
to 8 hydroxy groups and 2 to 12 carbon atoms (on average, if it is
a mixture as in polyglycerols). The polyol preferably is
polyglycerol, in particular that having the specific oligomer
distribution described in WO 95/34528.
[0087] The carboxylic acid used in the polyol polyester preferably
is a fatty acid having from 6 to 30 carbon atoms (Hereinafter,
unless stated otherwise, the term "fatty acid" is not limited to
the naturally occurring, even-numbered, saturated or unsaturated
long-chain carboxylic acids, but also includes their
uneven-numbered homologues or branched derivatives thereof. It may
also include double bonds at positions where they do not naturally
occur. Correspondingly, "fatty acid" is used as synonymous of
linear or branched, substituted or unsubstituted, saturated or
unsaturated aliphatic carboxylic acid. Unless stated otherwise, the
fatty acid has from 6 to 30 carbon atoms, preferably from 12 to 24
carbon atoms).
[0088] Particularly preferred is a fatty acid containing at least
one hydroxy group, a mixture or condensation products (poly(hydroxy
fatty acids)) thereof. The preferred carbon range for the above
mentioned carboxylic acid, as well as for fatty acids or hydroxy
fatty acids, is from 12 to 24, in particular 16 to 18. A
particularly preferred poly(hydroxy fatty acid) is the condensation
product of hydroxy stearic acid, in particular 12-hydroxy stearic
acid, optionally in admixture with poly(ricinoleic acid), said
condensation product having the properties described in WO
95/34528. Preferred emulsifiers include the polyol
poly(hydroxystearates) described in WO 95/34528, in particular
polyglycerol poly(hydroxystearates) having the characteristics
disclosed in this document, e.g.
(polyglycerin-2-dipolyhydroxystearate). This product is
commercially available from Cognis Deutschland GmbH under the
tradename Dehymuls.RTM. PGPH.
[0089] The weight ratio of the W/O emulsifier to the oil
component(s) preferably ranges from 0.2 to 2.0.
1.4. Coemulsifier (D)
[0090] The W/O emulsion used in the present invention comprises 0.5
to 10% by weight, preferably 2 to 8.5% by weight, in particular 4
to 7% by weight of at least one coemulsifier based on an ethylene
oxide-modified glyceride.
[0091] The glyceride component of this coemulsifier is preferably a
triglyceride. The fatty acid component of this glyceride preferably
has from 12 to 24 carbon atoms. Preferably, the ethylene oxide is
chemically linked to the fatty acid portion of the glyceride. This
is preferably achieved by using fatty acid components carrying at
least one protic functionality, such as hydroxy or amino, hydroxy
being preferred. According to preferred embodiments, the fatty acid
proportion thus represents a C.sub.12-C.sub.24, in particular
C.sub.16-C.sub.20 fatty acid which may be unsaturated and carries
at least one hydroxy group on the fatty acid chain. One preferred
example for a hydroxy fatty acid of this type is (R)-(Z)-12
hydroxy-9-octadecenoic acid (ricinoleic acid) and more preferably
the hydrogenated (saturated) derivative thereof. Moreover, it is
preferred that one mol of glyceride is modified with 2 to 15 mol
(in average) ethylene oxide, in particular 5 to 9 mol ethylene
oxide.
[0092] It should be noted that, as coemulsifier (D), commercially
available mixtures can be used which contain the ethylene
oxide-modified glyceride as a major component (more than 50% by
weight, in particular more than 75% by weight). One example for
commercially available products of this type is Dehymuls.RTM. HRE-7
(available from Cognis Deutschland GmbH).
1.5. Optional Humectant (E)
[0093] The lotion composition may comprise from 1 to 15% by weight,
preferably 2 to 7% by weight and in particular 3 to 5% by weight
(water-soluble) humectant (e.g. 3.5 to 4.5% by weight).
[0094] The humectant performs multiple functions. First, it binds
water and counteracts the tendency of water to evaporate. Moreover,
the humectant may interact with other lotion components and can
contribute to the softness of the tissue paper, in particular its
bulk softness.
[0095] The humectant preferably is a polyhydroxy compound, which is
understood to be an organic compound having at least two hydroxy
groups and which preferably consists only of carbon, hydrogen,
oxygen and nitrogen, in particular only of C, H and O. It is
further desirable that the humectant is not ionic.
[0096] Although hydrophilic surfactants (having a HLB number of 10
or greater, see for instance U.S. Pat. No. 4,764,418) can have
humectant properties, it is preferred according to the invention
that the humectant be free of major hydrophobic molecule parts,
e.g. fatty acid or fatty alcohol residues.
[0097] Further, the humectant preferably has a liquid consistency,
even though it is possible to use a minor amount of a solid, low
melting point humectant if the weight proportion of the remaining
solid lotion ingredients is low.
[0098] If liquid humectants are to be employed, the molecular
weight (weight average) preferably is less than 1,000, more
preferably less than 800, and in particular not more than 600.
[0099] Examples of suitable humectants include: glycerol,
diglycerol, triglycerol, ethylene glycol, propylene glycol,
butylene glycol, 1,2,6 hexanetriol, polyalkylene glycols, e.g.
polyethylene glycol or polypropylene glycol, for instance
polyethylene glycol having a weight average molecular weight of
from about 200 to 600; neopentyl alcohols such as pentaerythritol
or neopentyl glycol; sugar alcohols such as threitol, erythritol,
adonitol (ribitol), arabitol, xylitol, dulcitol, mannitol and
sorbitol, carbohydrates such as D (+)-glucose, D (+)-fructose, D
(+)-galactose, D (+)-mannose, L-gulose, saccharose, galactose,
maltose, polyglycerols, polyoxypropylene adducts of glycerol,
methoxypolyethylene glycol, polyethylene glycol ethers of sugar
alcohols, such as sorbitol, polyethylene glycol ethers of glycerol,
and combinations thereof. Hyaluronic acid may also be used as
humectant.
[0100] One preferred humectant is glycerol.
1.6. Metal Soaps (F) (Optional)
[0101] In order to stabilize the W/O emulsion, further a metal soap
of the following preferred formula may be used (up to 10% by
weight), preferably in an amount of 0.5 to 5, in particular 3 to 4%
by weight:
(R.sup.1COO).sub.n--X
wherein R.sup.1CO represents a fatty acid-derived acyl group, in
particular a linear, saturated or unsaturated acyl residue having 6
to 24 carbon atoms and optionally a hydroxy group, preferably one
having 12 to 20 carbon atoms, X is an alkali metal (e.g. Li), an
earth alkali metal (e.g. Ca, Mg), Al or Zn and n is the valence of
X. Preferred examples of the metal soap involve zinc, calcium,
magnesium or aluminium stearate.
1.7. Water (G)
[0102] The lotion composition contains 6 to 35% by weight, more
preferably 10 to 30% by weight, in particular 15 to 25% by weight
of water. The water contributes to a lotion-like pleasant feel on
the skin of the user, for instance during blowing the nose with a
treated handkerchief. Water counteracts further the tendency of
pure humectants to withdraw water from the human skin. On the other
hand, the water content should not be much higher than 35% by
weight, since then the mechanical strength of the treated tissue
paper may suffer.
[0103] It is possible to determine the water content in the lotion
composition by conducting a water determination according to Karl
Fischer. This may also be done with the treated tissue paper. Then
the entire lotion is extracted with suitable organic solvents, such
as water-free ethanol followed by the water determination of the
ethanol extract according to Karl Fischer. If necessary, the
residual water content of the treated tissue paper is to be
subtracted.
1.8. Optional Additives (H)
[0104] Optionally, the lotion composition may contain up to 10% by
weight, in particular 0.01 to 5% by weight additives (e.g. 0.05 to
3% by weight), such as [0105] Preservatives which stabilize the
lotion composition, such as methylisothiazolin(on) which may have a
chlorine as substituent, e.g. 5-chloro-2-methyl-4-isothiazolin-3-on
or 2-methyl-4-isothiazolin-3-on; phenoxyethanol or PHB ester,
paraben preservatives, pentanediol, sorbic acid or other compounds
as mentioned in "Kosmetikverordnung (Cosmetics Regulation), Anlage
4, Teil A und B". [0106] Germicidal agent(s), e.g. those described
in DE-199 06 081 A. [0107] Cosmetic agents, preferably from natural
sources (plant extracts), having for instance a skin-soothing,
antiphlogistic (reduction of skin irritation), wound-healing,
cell-regenerating, anti-inflammatory and/or anti-itch effect such
as allantoin; aloe vera extract; chamomile extract containing
azulene and .alpha.-bisabolol; echinacea; dragosantol; panthenol;
liquorice root extract containing 18-glycyrrhetinic acid; lime tree
extract containing quercetin and/or glyco-rutin; marigold
(calendula oil); lime-blossom extract; sage extract, melissa
extract; urea; phytosterols, optionally ethoxylated (available from
Henkel under the tradename "Generol"); chitosan (acetylated
chitin); anthocyanidins; ginkgo leaf extract containing quercetin
and rutin; horse chestnut containing quercetin and campherol;
vitamins or provitamins such as provitamin B5 or Vitamin E; avocado
oil; birch extract; arnica; extract of rose of Sharon or St. John's
wort; teatree oil; cucumber, hops, or hamamelis extracts or
ingredients, ethoxylated quaternary amines; wound-healing protein
hydrolysates; [0108] Perfume, e.g. those described in DE 199 06
081; and/or [0109] Cosmetically useful dyes and pigments, e.g.
those described in "Kosmetische Farbemittel" (Cosmetic coloring
agents), Verlag Chemie, Weinheim, 1984, p. 81-106")", published by
the "Farbstoffkommission der Deutschen Farbstoffgemeinschaft".
[0110] One preferred type of additives are plant extracts of the
type as already mentioned above which often contain one or more
wound-healing/soothing agents. Typically these extracts are
prepared by extracting the entire plant. In some cases it can also
be preferred to use solely the blossom and/or leaves of the plant.
Preferred extracts are obtained from chamomile aloe vera,
hamamelis, lime-blossom, sage and melissa. It is one additional
merit of the present invention that plant extracts can be used
without undesired coloring reactions of the lotion.
[0111] The above additives may be used separately or in
combination.
1.9. Most Preferred Lotion
[0112] The most preferred lotion composition, which based on
current knowledge reflects the best mode for carrying out the
invention, comprises the following components: [0113] (A) 25 to 35
weight % mineral oil, [0114] (B) 20 to 30 weight % of a further oil
component selected from liquid synthetic triglyceride mixtures;
vegetable oils; guerbet alcohols; liquid esters; liquid substituted
cyclohexanes; symmetric or asymmetric dialk(en)ylethers having from
6 to 22 C atoms per alk(en)yl group; linear or branched
dialk(en)ylcarbonate derived from C6 to C22 fatty alcohols;
ring-opening products of epoxidized fatty acid esters and polyols;
and silicone oils; [0115] (C) 12 to 21 weight % of a W/O emulsifier
selected from liquid polyol polyester wherein a polyhydric alcohol
having at least two hydroxy groups is esterified with at least one
acid having from 6 to 30 carbon atoms, [0116] (D) 4 to 7 weight %
coemulsifier based on a glyceride comprising a hydroxy fatty acid
being modified with the adduct of 2 to 15 mol ethylene oxide,
[0117] (E) optionally 1 to 10 weight % humectant, [0118] (F)
optionally 0.5 to 5 weight % of a metal soap [0119] (G) 10 to 30
weight % water, [0120] (H) optionally 0.1 to 5 weight %
additives.
2. Preparation of Lotion
[0121] The lotion composition (water-in-oil emulsion) can be
prepared according to known methods.
[0122] One procedure involves mixing and homogeneously stirring the
oil phase components, such as the oil components (A) and (B), and
the emulsifiers (C) and (D) and other optional oil-soluble
additives at room temperature (usually for approximately 10 min).
These components are typically highly soluble and give rise to a
homogeneous mixture. The components of the water phase such as
water, humectant, and possible water-soluble or water-dispersible
additives such as perfume or preservatives are separately mixed at
room temperature and slowly added to the mixture of oil-phase
components during continuous stirring. After continued stirring
(preferably for approximately 10 min) the resulting mixture is then
homogenized (usually for approximately 10 min) with a suitable
dispersion device such as supraton or stator-rotor homogenizers of
Ultraturrax type (see for instance Karlheinz Schrader, Grundlagen
und Rezepturen der Kosmetika, Huthig Buch Verlag Heidelberg, Second
Edition, 1989, pages 906 to 912). As known from the prior art,
homogenizing conditions may have an impact on the viscosity of the
emulsion obtained. If the viscosity is too high, which is
undesirable in the present invention, it is possible for instance
to reduce the energy influx during homogenization, in particular by
lowering the rotational speed of the rotor/stator system.
[0123] Further, it is possible to prepare the lotion composition of
the invention by mixing the oil phase and water phase components at
a higher temperature. For this purpose, it is preferred to heat the
oil phase and water phase components separately to about 80.degree.
C. to 85.degree. C. Then, at this temperature the water phase
components are slowly added to the oil phase components while
stirring, optionally homogenizing. After continued stirring,
preferably for about 5 min, the mixture is allowed to cool while
stirring in such a way that it remains in continuous motion.
Simultaneously, the incorporation of air should be avoided. The
mixture is then homogenized with a suitable dispersion device such
as supraton or stator-rotor homogenizers of Ultraturrax type,
preferably at 60.degree. to 65.degree. C., in order to improve
stability and structure. After a homogeneous state is reached, the
composition is allowed to cool to room temperature.
3. Tissue Paper to be Treated
[0124] Based on the underlying compatibility of the production
processes (wet laying), "tissue" production is counted among the
paper making techniques. The production of tissue is distinguished
from paper production by its extremely low basis weight of normally
80 g/m.sup.2 or less, in particular 65 g/m.sup.2 or less and its
much higher tensile energy absorption index. The tensile energy
absorption index is arrived at from the tensile energy absorption
in which the tensile energy absorption is related to the test
sample volume before inspection (length, width, thickness of sample
between the clamps before tensile load). Paper and tissue paper
also differ in general with regard to the modulus of elasticity
that characterizes the stress-strain properties of these planar
products as a material parameter.
[0125] A tissue's high tensile energy absorption index results from
the outer or inner creping. The former is produced by compression
of the paper web adhering to a dry cylinder as a result of the
action of a crepe doctor or in the latter instance as a result of a
difference in speed between two wires ("fabrics"). In the latter
technique, often referred to as "(wet) rush transfer", for instance
the forming fabric of the paper machine is moved at greater speed
than that of the fabric to which the formed paper web is
transferred, for instance a transfer fabric or a TAD fabric
(through air drying), so that the paper web is somewhat bundled
when it is taken up by the transfer fabric.
[0126] Many prior art documents (e.g. EP-A-0 617 164, WO-94/28244,
U.S. Pat. No. 5,607,551, EP-A-0 677 612, WO-96/09435) refer to this
as "inner creping", when they describe the production of "uncreped"
tissue paper by rush transfer techniques. The inner and outer
creping causes the still moist, plastically deformable paper web to
be internally broken up by compression and shearing, thereby
rendering it more stretchable under load than uncreped paper. Most
of the functional properties typical of tissue and tissue products
result from a high tensile energy absorption index (see DIN EN
126254 and DIN EN 12625-5).
[0127] Typical properties of tissue paper include the ready ability
to absorb tensile stress energy, their drapability, good
textile-like flexibility, a high specific volume with a perceptible
thickness, as high a liquid absorbency as possible and, depending
on the application, a suitable wet and dry strength as well as an
interesting visual appearance of the outer product surface.
[0128] According to the invention creped or "uncreped" tissue paper
can be lotioned, the use of creped tissue paper being preferred.
The tissue paper (or the final tissue paper product obtained
therefrom) can be single-ply or multi-ply (typically 2 to 6). The
penetration behavior of the lotion is particular suitable for
multi-ply tissues (or tissue products), in particular 4-ply
embodiments as used in handkerchiefs, since the lotion can be
almost evenly distributed over the outer and inner plies. The
tissue paper may be homogeneous or layered, wet-pressed or
blow-dried (TAD-dried). The tissue paper includes, but is not
limited to, felt-pressed tissue paper, pattern-densified tissue
paper, uncompacted tissue paper or compacted tissue paper.
[0129] The starting material for the production of the tissue paper
usually is a fibrous cellulosic material, in particular pulp.
[0130] If, however, linters or cotton is used as raw material for
the production of tissue paper, usually no further pulping steps
are needed. Due to the morphological structure, the cellulose
already exists in an open state.
[0131] The starting pulps used may relate to primary fibrous
materials (raw pulps) or to secondary fibrous materials, whereby a
secondary fibrous material is defined as a fibrous raw material
recovered from a recycling process. The primary fibrous materials
may relate both to a chemically digested pulp and to mechanical
pulp such as thermorefiner mechanical pulp (TMP),
chemothermorefiner mechanical pulp (CTMP) or high temperature
chemithermomechanical pulp (HTCTMP). Synthetic cellulose-containing
fibres can also be used. Preference is nevertheless given to the
use of pulp from plant material, particularly wood-forming plants.
Fibers of softwood (usually originating from conifers), hardwood
(usually originating from deciduous trees) or from cotton linters
can be used for example. Fibres from esparto (alfa) grass, bagasse
(cereal straw, rice straw, bamboo, hemp), kemp fibers, flax, and
other woody and cellulosic fiber sources can also be used as raw
materials. The corresponding fiber source is chosen in accordance
with the desired properties of the end product in a manner known
from the prior art. For example, the fibers present in hardwood,
which are shorter than those of softwood, lend the final product a
higher stability on account of the higher diameter/length ratio. If
softness of the product is to be promoted, which is important e.g.
for tissue paper, eucalyptus wood is particularly suitable as a
fiber source.
[0132] With regard to softness of the products, the use of chemical
raw pulps is also preferred, whereby it is possible to use
completely bleached, partially bleached, and unbleached fibers. The
chemical raw pulps suitable according to the invention include
inter alia, sulphite pulps, kraft pulps (sulphate process).
[0133] Before a raw pulp is used in the tissue making process, it
may also be advantageous to allow further delignification to occur
in a separate process step or employ a bleaching process to achieve
a more extensive removal of lignin after the cooking process and to
obtain a completely cooked pulp.
[0134] A preferred production process for tissue paper uses [0135]
a a forming section (for wet-laying a slurry of cellulosic fibrous
material, typically pulp) comprising a headbox and wire portion,
and [0136] b the drying section (TAD (through air drying) or
conventional drying on the yankee cylinder) that also usually
includes the crepe process essential for tissues. This is typically
followed by [0137] c the monitoring and winding area.
[0138] The tissue paper can be formed by placing the fibers, in an
oriented or random manner, on one or between two continuously
revolving wires of a paper-making machine while simultaneously
removing the main quantity of water of dilution until dry-solid
contents of usually between 12 and 35% are obtained. It is possible
to include additives in the paper furnish to improve the
wet-strength or dry-strength or other properties of the finished
tissue paper.
[0139] Drying the formed primary fibrous web occurs in one or more
steps by mechanical and thermal means until a final dry-solids
content of usually about 93 to 97% is obtained. In the case of
tissue making, this stage is followed by the crepe process which
crucially influences the properties of the finished tissue product
in conventional processes. The conventional dry crepe process
involves creping on a drying cylinder having a diameter of usually
4.5 to 6 m, the so-called yankee cylinder, by means of a crepe
doctor with the aforementioned final dry-solids content of the base
("raw tissue") tissue paper (wet creping can be used if lower
demands are made of the tissue quality). The creped, finally dry
base tissue paper is then available for further processing into the
paper product or tissue paper product according to the
invention.
[0140] Instead of the conventional tissue making process described
above, the invention gives preference to the use of a modified
technique in which an improvement in specific volume is achieved by
a special kind of drying within process section b and in this way
an improvement in bulk softness of the resulting tissue paper is
achieved. This pre-drying process, which exists in a variety of
subtypes, is termed the TAD (through air drying) technique. It is
characterized by the fact that the "primary" fibrous web (like a
non-woven) that leaves the sheet making stage is pre-dried to a
dry-solids content of about 80% before final contact drying on the
yankee cylinder by blowing hot air through the fibrous web. The
fibrous web is supported by an air-permeable wire or belt and
during its transport is guided over the surface of an air-permeable
rotating cylinder drum. Structuring the supporting imprinting
fabric or belt makes it possible to produce any pattern of
compressed and uncompressed zones achieved by deflection of the
fibres in the moist state, followed by pre-drying (TAD step) and
leading the web through a pressure nip between a pressure roll and
the Yankee cylinder surface, thereby resulting in increased mean
specific volumes and consequently leading to an increase in bulk
softness without decisively decreasing the strength of the fibrous
web.
[0141] Another possible influence on softness and strength of base
tissue lies in the production of a layering in which the primary
fibrous web to be formed is built up by a specially constructed
headbox in the form of physically different layers of fibrous
material, these layers being jointly supplied as a pulp jet to the
forming stage.
[0142] The one-ply intermediate products originating from the
paper-making machine and made of lightweight paper usually
dry-creped on a yankee cylinder by means of a crepe doctor are
generally described as "tissue paper" or more accurately base
tissue paper. The one-ply base tissue may be built up of one or a
plurality of layers respectively.
[0143] All one-ply or multi-ply final products made of base tissue
and tailored to the end user's needs, i.e. manufactured with a wide
variety of requirements in mind, are known as "tissue
products".
[0144] When processing the fibrous web or base tissue paper into
the final tissue product, the following procedural steps are
normally used individually or in combination: cutting to size
(longitudinally and/or cross cutting), producing a plurality of
plies, producing mechanical and/or chemical ply adhesion,
volumetric and structural embossing, folding, imprinting,
perforating, application of lotions, smoothing, stacking, rolling
up.
[0145] To produce multi-ply tissue paper products, such as
handkerchiefs, toilet paper, towels or kitchen towels, an
intermediate step preferably occurs with so-called doubling in
which the base tissue in the finished product's desired number of
plies is usually gathered on a common multiply master roll.
[0146] The processing step from the base tissue that has already
been optionally wound up in several plies to the finished tissue
product occurs in processing machines which include operations such
as repeated smoothing of the tissue, edge embossing, to an extent
combined with full area and/or local application of adhesive to
produce ply adhesion of the individual plies (base tissue) to be
combined together, as well as longitudinal cut, folding, cross cut,
placement and bringing together a plurality of individual tissues
and their packaging as well as bringing them together to form
larger surrounding packaging or bundles. The individual paper ply
webs can also be pre-embossed and then combined in a roll gap
according to the foot-to-foot or nested methods.
[0147] Embossing can be used for generating ply adhesion in
multi-ply tissue papers. In order to ensure that the lotion does
not lower the ply adhesion, the embossed regions may be left
untreated. Further it is known from U.S. Pat. No. 4,867,831 to use
melted thermoplastics to achieve plybonding in lotioned tissue
papers.
[0148] Tissue products using the lotioned tissue of the invention
are preferably sanitary products (e.g. toilet paper), paper
handkerchiefs, cosmetic wipes (facials) or as serviettes/napkins.
The use in handkerchiefs is preferred.
[0149] According to the invention the tissue paper to be treated
with the lotion preferably has a basis weight of 8 to 40 g/m.sup.2,
more preferably 10 to 30 g/m.sup.2, even more preferably 12 to 20
g/m.sup.2 per ply, in particular 13 to 17 g/m.sup.2 and a total
basis weight (including all plies without lotion) of usually 10 to
80 g/m.sup.2.
4. Application of Lotion on the Tissue Paper
[0150] As mentioned, lotion application typically takes place after
the paper web has been dried. A suitable point in time is for
example directly after drying the web, shortly before combining the
webs to form multiple plies or before forming the multi-ply web
into the final tissue product. However, it is preferred first to
laminate at least two single ply webs to a multiply web, and then
to apply the lotion. For tissue paper having two or more plies, the
composition may be applied to each ply or only to one or both outer
plies. In a preferred production process for lotioned 4-ply tissue
(products), two 2-ply webs are each lotioned on only one side,
followed by joining together the untreated sides of said 2-ply
webs, thereby obtaining a 4 ply product. Generally, it is preferred
for the lotion composition to be applied to at least one,
preferably both outer plies of multi-ply tissue webs, since then
the advantageous penetration behaviour of the lotion composition
can fully be developed by achieving as even a distribution as
possible with respect to the z-direction (perpendicular) of the
multi-ply tissue paper. The individual plies or the multi-ply
structure may be patterned either before or after application of
the lotion composition. Suitable application techniques include
spraying, rotogravure printing or flexographic printing or
application by means of rolls having a smooth surface. Preferably,
the lotion composition is slightly heated, in particular to a
temperature from 25.degree. to 50.degree. C., preferably between 30
and 45.degree. C. before it is applied to the paper web.
[0151] Preferably, the lotion is applied in an amount of 3 to 10 g
per m.sup.2 treated surface, i.e. with double the amount if both
surfaces are lotioned being preferred. The weight ratio lotion
composition/tissue (single or multi-ply) is preferably 10 to 40%,
more preferably 21 to 35%, in particular 25 to 30%. With four-ply
products a particularly good and even distribution of the lotion
composition is observed when the weight ratio is from 22 to 30%, in
particular 27 to 29%.
5. Example
[0152] The following two lotions were prepared at room temperature
by mixing and homogenizing the respective components. The lotion
referred to as comparative example 1 corresponds to a lotion
described in WO 02/056842 A2 and WO 02/057546 A1. Both lotions were
assessed with respect to their stability, whiteness (according to
DIN EN 12625-7, item 7.3.2, colour (D65/10.degree.)) and sensory
impression. As a reference point for the whiteness analysis, the
whiteness of unlotioned tissue paper was taken as 100%. In
accordance with the present invention, it is preferred that the
decrease in whiteness is less than 3.9%, preferably less than 3.75,
in particular less than 3.5%. The inventive example 1 satisfied
this requirement.
[0153] For the stability tests samples of the produced lotions were
stored under the conditions given in Table 1. Where phase
separation was observed with the naked eye, the lotion was rated
"-".
[0154] The sensory test was conducted by an experienced panel of
test persons. The optimum sensory impression was rated "1" whilst a
poor sensory impression is reflected by "6".
TABLE-US-00001 TABLE 1 Comparative Ingredients Example 1 Example 1
Polyglycerin-2- 15 20.6 dipolyhydroxystearate Hydrogenated castor
oil + 5 - 7EO Mineral oil 30 - Ethylhexyl stearate 22.4 -
Cocoglyceride - 20.6 Dicaprylyl ether - 20.6 Sorbitan sesquiolate -
4.8 Beeswax - 3.35 Dicocoyl pentaerythrityl - 2 distearyl citrate
Tocopheryl and - 0.02 hydrogenated palm glyceride citrate Glycerol
4 7 Magnesium stearate 3.5 - Aluminium stearate - 2.75 Blossom
extract from 0.1 0.1 chamomilla recutita (matricaria) Water 20 18.2
Preservative As required Appearance milky-white milky-yellow
Stability 4 weeks-RT + + Stability 8 weeks-RT + - Stability 4
weeks-30.degree. C. + - Decrease in whiteness (%) 3.4 3.9 Sensory
impression of 1.0 4.0 lotion-creaminess
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