Soft absorbent tissue paper containing a biodegradable quaternized amine-ester softening compound and a temporary wet strength resin

Tissue paper webs useful in the manufacture of soft, absorbent products such as napkins, facial tissues, and sanitary tissues, and processes for making the webs. The tissue paper webs comprise papermaking fibers, a biodegradable quaternized amine-ester softening compound, a wetting agent, and a temporary wet strength resin. The process comprises a first step of forming an aqueous papermaking furnish from the above-mentioned components. The second and third steps in the basic process are the deposition of the papermaking furnish onto a foraminous surface such as a Fourdrinier wire and removal of the water from the deposited furnish. An alternate process involves the use of the furnish containing the aforementioned components in a papermaking process which will produce a pattern densified fibrous web having a relatively high bulk field of relatively low fiber density in a patterned array of spaced zones of relatively high fiber density.

FIELD OF THE INVENTION 
This invention relates to tissue paper webs. More particularly, it relates 
to soft, absorbent tissue paper webs which can be used in sanitary tissue, 
facial tissue products, and paper napkins. 
BACKGROUND OF THE INVENTION 
Paper webs or sheets, sometimes called tissue or paper tissue webs or 
sheets, find extensive use in modern society. Such items as paper towels, 
napkins, and facial tissues are staple items of commerce. It has long been 
recognized that three important physical attributes of these products are 
their softness; their absorbency, particularly their absorbency for 
aqueous systems; and their strength, particularly their strength when wet. 
Research and development efforts have been directed to the improvement of 
each of these attributes without deleteriously affecting the others as 
well as to the improvement of two or three attributes simultaneously. 
Softness is the tactile sensation perceived by the consumer as he/she holds 
a particular product, rubs it across his/her skin, or crumples it within 
his/her hand. This tactile sensation is a combination of several physical 
properties. One of the more important physical properties related to 
softness is generally considered by those skilled in the art to be the 
stiffness of the paper web from which the product is made. Stiffness, in 
turn, is usually considered to be directly dependent on the dry tensile 
strength of the web. 
Strength is the ability of the product, and its constituent webs, to 
maintain physical integrity and to resist tearing, bursting, and shredding 
under use conditions, particularly when wet. 
Absorbency is the measure of the ability of a product, and its constituent 
webs, to absorb quantities of liquid, particularly aqueous solutions or 
dispersions. Overall absorbency as perceived by the human consumer is 
generally considered to be a combination of the total quantity of liquid a 
given mass of tissue paper will absorb at saturation as well as the rate 
at which the mass absorbs the liquid. 
The use of wet strength resins to enhance the strength of a paper web is 
widely known. For example, Westfelt described a number of such materials 
and discussed their chemistry in Cellulose Chemistry and Technology, 
Volume 13, at pages 813-825 (1979). 
Freimark et al. in U.S. Pat. No. 3,755,220 issued Aug. 28, 1973 mention 
that certain chemical additives known as debonding agents interfere with 
the natural fiber-to-fiber bonding that occurs during sheet formation in 
papermaking processes. This reduction in bonding leads to a softer, or 
less harsh, sheet of paper. Freimark et al. go on to teach the use of wet 
strength resins to enhance the wet strength of the sheet in conjunction 
with the use of debonding agents to off-set undesirable effects of the 
debonding agents. These debonding agents do reduce dry tensile strength, 
but there is also generally a reduction in wet tensile strength. 
Shaw, in U.S. Pat. No. 3,821,068, issued Jun. 28, 1974, also teaches that 
chemical debonders can be used to reduce the stiffness, and thus enhance 
the softness, of a tissue paper web. 
Chemical debonding agents have been disclosed in various references such as 
U.S. Pat. No. 3,554,862, issued to Hervey et al . on Jan. 12, 1971. These 
materials include quaternary ammonium salts such as trimethylcocoammonium 
chloride, trimethyloleylammonium chloride, 
di(hydrogenated-tallow)dimethylammonium chloride and 
trimethylstearylammonium chloride. 
Emanuelsson et al., in U.S. Pat. No. 4,144,122, issued Mar. 13, 1979, teach 
the use of complex quaternary ammonium compounds such as 
bis(alkoxy-(2-hydroxy)-propylene) quaternary ammonium chlorides to soften 
webs. These authors also attempt to overcome any decrease in absorbency 
caused by the debonders through the use of nonionic surfactants such as 
ethylene oxide and propylene oxide adducts of fatty alcohols. 
Armak Company, of Chicago, Ill., in their bulletin 76-17 (1977) disclose 
that the use of di(hydrogenated-tallow)dimethylammonium chloride in 
combination with fatty acid esters of polyoxyethylene glycols may impart 
both softness and absorbency to tissue paper webs. 
One exemplary result of research directed toward improved paper webs is 
described in U.S. Pat. No. 3,301,746, issued to Sanford and Sisson on Jan. 
31, 1967. Despite the high quality of paper webs made by the process 
described in this patent, and despite the commercial success of products 
formed from these webs, research efforts directed to finding improved 
products have continued. 
For example, Becker et al. in U.S. Pat. No. 4,158,594, issued Jan. 19, 
1979, describe a method they contend will form a strong, soft, fibrous 
sheet. More specifically, they teach that the strength of a tissue paper 
web (which may have been softened by the addition of chemical debonding 
agents) can be enhanced by adhering, during processing, one surface of the 
web to a creping surface in a fine patterned arrangement by a bonding 
material (such as an acrylic latex rubber emulsion, a water soluble resin, 
or an elastomeric bonding material) which has been adhered to one surface 
of the web and to the creping surface in the fine patterned arrangement, 
and creping the web from the creping surface to form a sheet material. 
Conventional quaternary ammonium compounds such as the well known 
dialkyldimethylamonium salts (e.g., ditallowdimethylammonium chloride, 
ditallowdimethyammonium methylsulfate, di(hydrogenated tallow)dimethyl 
ammonium chloride, etc.) are effective chemical debonding agents. 
Unfortunately, these quaternary ammonium compounds are not biodegradable. 
Applicant has discovered that biodegradable mono- and diester variations 
of these quaternary ammonium salts also function effectively as chemical 
debonding agents and enhance the softness of tissue paper webs. 
It is an object of this invention to provide a process for making soft, 
absorbent tissue paper webs with high temporary wet strength. 
It is a further object of this invention to provide soft, absorbent tissue 
paper sheets with high temporary wet strength and that are biodegradable. 
It is a still further object of this invention to provide soft, absorbent 
sanitary tissue products with high temporary wet strength and that are 
biodegradable. 
These and other objects are obtained using the present invention, as will 
become readily apparent from a reading of the following disclosure. 
SUMMARY OF THE INVENTION 
The present invention provides soft, absorbent tissue paper webs having 
high temporary strength, and a process for making the webs. Briefly, the 
tissue paper webs comprise: 
(a) papermaking fibers; 
(b) from about 0.01% to about 2.0% by weight of a quaternized amine-ester 
compound having the formula 
##STR1## 
and mixtures thereof; wherein each R substituent is a C.sub.1 -C.sub.6 
alkyl or hydroxyalkyl group, or mixtures thereof; R.sup.1 is 
##STR2## 
or a C.sub.13 -C.sub.19 hydrocarbyl group or mixtures thereof; R.sup.2 is 
a C.sub.13 -C.sub.21 hydrocarbyl group or mixtures thereof; and X.sup.- is 
a compatible anion; 
(c) from about 0.01% to about 2.0% by weight of a wetting agent; and 
(d) from about 0.01% to about 3.0% by weight of a water-soluble temporary 
wet strength resin. 
Examples of quaternized amine-ester softening compounds suitable for use in 
the present invention include compounds having the formulas: 
##STR3## 
These compounds can be considered to be mono- and di- ester variations of 
the well-known dialkyldimethylammonium salts such as 
ditallowdimethylammonium chloride, ditallowdimethylammonium methylsulfate, 
di(hydrogenated tallow)dimethylammonium chloride, with the diester 
variations of di(hydrogenated tallow)dimethylammonium methylsulfate and 
di(hydrogenated tallow)dimethylammonium chloride being preferred. Without 
being bound by theory, it is believed that the ester moiety(ies) lends 
biodegradability to these compounds. 
Examples of wetting agents useful in the present invention include 
polyhydroxy compounds such as glycerol and polyethylene glycols having a 
molecular weight of from about 200 to about 2000, with polyethylene 
glycols having a molecular weight of from about 200 to about 600 being 
preferred. Other examples of suitable wetting agents include alkoxylated 
alcohols, with linear alkoxylated alcohols and linear alkyl phenoxylated 
alcohols being preferrred. 
The temporary wet strength resins useful in the present invention include 
all those commonly used in papermaking. Examples of preferred temporary 
wet strength resins include cationic starch-based resins and the cationic 
polymers described in U.S. Pat. No. 4,981,557, Bjorkquist, issued Jan. 1, 
1991. 
A particularly preferred tissue paper embodiment of the present invention 
comprises from about 0.01% to about 0.5% by weight of the quaternized 
amine-ester softening compound, from about 0.01% to about 0.5% by weight 
of the wetting agent, and from about 0.1% to about 1.5% by weight of the 
water-soluble temporary wet strength resin, all quantities of these 
additives being on a dry fiber weight basis of the tissue paper. 
Briefly, the process for making the tissue webs of the present invention 
comprises the steps of forming a papermaking furnish from the 
aforementioned components, deposition of the papermaking furnish onto a 
foraminous surface such as a Fourdrinier wire, and removal of the water 
from the deposited furnish. 
All percentages, ratios and proportions herein are by weight unless 
otherwise specified. 
The present invention is described in more detail below.

DETAILED DESCRIPTION OF THE INVENTION 
While this specification concludes with claims particularly pointing out 
and distinctly claiming the subject matter regarded as the invention, it 
is believed that the invention can be better understood from a reading of 
the following detailed description and of the appended examples. 
As used herein, the terms tissue paper web, paper web, web, and paper sheet 
all refer to sheets of paper made by a process comprising the steps of 
forming an aqueous papermaking furnish, depositing this furnish on a 
foraminous surface, such as a Fourdrinier wire, and removing the water 
from the furnish as by gravity or vacuum-assisted drainage, with or 
without pressing, and by evaporation. 
As used herein, an aqueous papermaking furnish is an aqueous slurry of 
papermaking fibers and the chemicals described hereinafter. 
The first step in the process of this invention is the forming of an 
aqueous papermaking furnish. The furnish comprises papermaking fibers 
(hereinafter sometimes referred to as wood pulp), at least one wet 
strength resin, at least one quaternary ammonium and at least one wetting 
agent, all of which will be hereinafter described. 
It is anticipated that wood pulp in all its varieties will normally 
comprise the papermaking fibers used in this invention. However, other 
cellulosic fibrous pulps, such as cotton linters, bagasse, rayon, etc., 
can be used and none are disclaimed. Wood pulps useful herein include 
chemical pulps such as Kraft, sulfite and sulfate pulps as well as 
mechanical pulps including for example, ground wood, thermomechanical 
pulps and chemically modified thermomechanical pulp (CTMP). Pulps derived 
from both deciduous (e.g., Eucalyptus pulp) and coniferous trees (e.g., 
spruce) can be used. Also applicable to the present invention are fibers 
derived from recycled paper, which may contain any or all of the above 
categories as well as other non-fibrous materials such as fillers and 
adhesives used to facilitate the original papermaking. Preferably, the 
papermaking fibers used in this invention comprise Kraft pulp derived from 
northern softwoods. 
Wet Strength Resins 
The present invention contains as an essential component from about 0.01% 
to about 3.0%, more preferably from about 0.1% to about 1.5% by weight, on 
a dry fiber weight basis, of a water-soluble temporary wet strength resin. 
Wet strength resins useful herein can be of several types. Generally, those 
resins which have previously found and which will hereafter find utility 
in the papermaking art are useful herein. Numerous examples are shown in 
the aforementioned paper by Westfelt, incorporated herein by reference. 
In the usual case, the wet strength resins are water-soluble, cationic 
materials. That is to say, the resins are water-soluble at the time they 
are added to the papermaking furnish. It is quite possible, and even to be 
expected, that subsequent events such as cross-linking will render the 
resins insoluble in water. Further, some resins are soluble only under 
specific conditions, such as over a limited pH range. 
Wet strength resins are generally believed to undergo a cross-linking or 
other curing reactions after they have been deposited on, within, or among 
the papermaking fibers. Cross-linking or curing does not normally occur so 
long as substantial amounts of water are present. 
Of particular utility are the various polyamide-epichlorohydrin resins. 
These materials are low molecular weight polymers provided with reactive 
functional groups such as amino, epoxy, and azetidinium groups. The patent 
literature is replete with descriptions of processes for making such 
materials. U.S. Pat. No. 3,700,623, issued to Keim on Oct. 24, 1972 and 
U.S. Pat. No. 3,772,076, issued to Keim on Nov. 13, 1973 are examples of 
such patents and both are incorporated herein by reference. 
Polyamide-epichlorohydrin resins sold under the trademarks Kymene 557H and 
Kymene LX by Hercules Incorporated of Wilmington, Del., are particularly 
useful in this invention. These resins are generally described in the 
aforementioned patents to Keim. 
Base-activated polyamide-epichlorohydrin resins useful in the present 
invention are sold under the Santo Res trademark, such as Santo Res 31, by 
Monsanto Company of St. Louis, Mo. These types of materials are generally 
described in U.S. Pat. Nos. 3,855,158 issued to Petrovich on Dec. 17, 
1974; 3,899,388 issued to Petrovich on Aug. 12, 1975; 4,129,528 issued to 
Petrovich on Dec. 12, 1978; 4,147,586 issued to Petrovich on Apr. 3, 1979; 
and 4,222,921 issued to Van Eenam on Sep. 16, 1980, all incorporated 
herein by reference. 
Other water-soluble cationic resins useful herein are the polyacrylamide 
resins such as those sold under the Parez trademark, such as Parez 631NC, 
by American Cyanamid Company of Stanford, Conn. These materials are 
generally described in U.S. Pat. Nos. 3,556,932 issued to Coscia et al. on 
Jan. 19, 1971; and 3,556,933 issued to Williams et al. on Jan. 19, 1971, 
all incorporated herein by reference. 
Other types of water-soluble resins useful in the present invention include 
acrylic emulsions and anionic styrene-butadiene latexes. Numerous examples 
of these types of resins are provided in U.S. Pat. No. 3,844,880, Meisel, 
Jr. et al., issued Oct. 29, 1974, incorporated herein by reference. 
Still other water-soluble cationic resins finding utility in this invention 
are the urea formaldehyde and melamine formaldehyde resins. These 
polyfunctional, reactive polymers have molecular weights on the order of a 
few thousand. The more common functional groups include nitrogen 
containing groups such as amino groups and methylol groups attached to 
nitrogen. 
Although less preferred, polyethylenimine type resins find utility in the 
present invention. 
More complete descriptions of the aforementioned water-soluble resins, 
including their manufacture, can be found in TAPPI Monograph Series No. 
29, Wet Strength In Paper and Paperboard, Technical Association of the 
Pulp and Paper Industry (New York; 1965), incorporated herein by 
reference. 
The above-mentioned wet strength additives typically result in paper 
products with permanent wet strength, i.e., paper which when placed in an 
aqueous medium retains a substantial portion of its initial wet strength 
over time. However, permanent wet strength in some types of paper products 
can be an unnecessary and undesirable property. Paper products such as 
toilet tissues, etc., are generally disposed of after brief periods of use 
into septic systems and the like. Clogging of these systems can result if 
the paper product permanently retains its hydrolysis-resistant strength 
properties. 
More recently, manufacturers have added temporary wet strength additives to 
paper products for which wet strength is sufficient for the intended use, 
but which then decays upon soaking in water. Decay of the wet strength 
facilitates flow of the paper product through septic systems. As used 
herein, the term "temporary wet strength resin" refers to a resin that 
allows the tissue paper, when placed in an aqueous medium, to lose a 
majority of its initial wet strength in a short period of time, e.g., two 
minutes or less, more preferably, 30 seconds or less. 
Examples of suitable temporary wet strength resins include modified starch 
temporary wet strength agents such as National Starch 78-0080, marketed by 
the National Starch and Chemical Corporation (New York, N.Y.). This type 
of wet strength agent can be made by reacting 
dimethoxyethyl-N-methyl-chloroacetamide with cationic starch polymers. 
Modified starch temporary wet strength agents are also described in U.S. 
Pat. No. 4,675,394, Solarek, et al., issued Jun. 23, 1987, and 
incorporated herein by reference. 
Preferred temporary wet strength resins include those described in U.S. 
Pat. No. 4,981,557, Bjorkquist, issued Jan. 1, 1991, and incorporated 
herein by reference. The temporary wet strength resins described in U.S. 
Pat. No. 4,981,557 comprise a polymer characterized by the substantially 
complete absence of nucleophilic functionalities and having the formula: 
##STR4## 
wherein: A is 
##STR5## 
and X is --O--, --NCH.sub.3 --, and R is a substituted or unsubstituted 
aliphatic groups; Y.sub.1 and Y.sub.2 are independently --H, --CH.sub.3 or 
a halogen; W is a nonnucleophilic, water-soluble nitrogen heterocyclic 
moiety; C is a cationic monomeric unit; the mole percent of a is from 
about 30% to about 70%, the mole percent of b is from about 30% to about 
70%, and the mole percent of c is from about 1% to about 40%; and said 
polymer has an average molecular weight of between about 30,000 and about 
200,000. 
With respect to the classes and specific examples of both permanent and 
temporary wet strength resins listed above, it should be understood that 
the resins listed are exemplary in nature and are not meant to limit the 
scope of this invention. 
Mixtures of compatible wet strength resins, such as the temporary wet 
strength resins described in U.S. Pat. No. 4,981,557 and the modified 
starch temporary wet strength resins described above, can also be used in 
the practice of this invention. 
Quaternized Amine-Ester Softening Compound 
The present invention contains as an essential component from about 0.01% 
to about 2.0%, more preferably from about 0.01% to about 0.5% by weight, 
on a dry fiber weight basis, of a quaternized amine-ester softening 
compound having the formula: 
##STR6## 
and mixtures thereof; wherein each R substituent is a short chain (C.sub.1 
-C.sub.6, preferably C.sub.1 -C.sub.3) alkyl or hydroxyalkyl group, e.g., 
methyl (most preferred), ethyl, propyl, hydroxyethyl, and the like, or 
mixtures thereof; R.sup.1 is 
##STR7## 
or a long chain C.sub.13 -C.sub.19 hydrocarbyl substituent, preferably 
C.sub.16 -C.sub.18 alkyl, most preferably straight-chain C.sub.18 alkyl ; 
R.sup.2 is a long chain C.sub.13 -C.sub.21 hydrocarbyl substituent, 
preferably C.sub.13 -C.sub.17 alkyl, most preferably C.sub.15 straight 
chain alkyl. The counterion X.sup.- is not critical herein, and can be any 
softener-compatible anion, such as an halide (e.g., chloride or bromide), 
or methylsulfate. Preferably, X.sup.- is methyl sulfate or chloride. It 
will be understood that substituents R, R.sup.1 and R.sup.2 may optionally 
be substituted with various groups such as alkoxyl, hydroxyl, or can be 
branched, but such materials are not preferred herein. The preferred 
compounds can be considered to be mono- and di- ester variations of the 
well-known dialkyldimethylammonium salts such as ditallowdimethylammonium 
chloride, ditallowdimethylammonium methylsulfate, di(hydrogenated 
tallow)dimethylammonium chloride, with the diester variations of 
di(hydrogenatedtallow)dimethylammonium methylsulfate or di(hydrogenated 
tallow)dimethylammonium chloride being preferred. 
Tallow is a naturally occurring material having a variable composition. 
Swern, Ed. in Bailey's Industrial Oil and Fat Products, Third Edition, 
John Wiley and Sons (New York 1964) in Table 6.13, indicates that 
typically 78% or more of the fatty acids of tallow contain 16 or 18 carbon 
atoms. Typically, half of the fatty acids present in tallow are 
unsaturated, primarily in the form of oleic acid. Synthetic as well as 
natural "tallows" fall within the scope of the present invention. 
The above compounds used as the active softener ingredient in the practice 
of this invention are prepared using standard reaction chemistry. For 
example, in a typical synthesis of a monoester variation of a 
dialkyldimethylammonium salt, an amine of the formula RR.sup.1 NCH.sub.2 
CH.sub.2 OH is esterified at the hydroxyl group with an acid chloride of 
the formula R.sup.2 C(O)Cl, then quaternized with an alkyl halide, RX, to 
yield the desired reaction product (wherein R, R.sup.1, and R.sup.2 are as 
defined in the present application). A method for the synthesis of a 
preferred mono-ester softening compound is disclosed in detail 
hereinafter. However, it will be appreciated by those skilled in the 
chemical arts that this reaction sequence allows a broad selection of 
compounds to be prepared. As illustrative, nonlimiting examples there can 
be mentioned the following quaternized amine monoesters (wherein all 
long-chain alkyl substituents are straight-chain): 
[CH.sub.3 ].sub.2 [CH.sub.18 H.sub.37 ].sup.+ NCH.sub.2 CH.sub.2 
OC(O)C.sub.15 H.sub.31 Br.sup.- 
[CH.sub.3 ].sub.2 [CH.sub.13 H.sub.27 ].sup.+ NCH.sub.2 CH.sub.2 
OC(O)C.sub.17 H.sub.35 Cl.sup.- 
[C.sub.2 H.sub.5 ].sub.2 [C.sub.17 H.sub.35 ].sup.+ NCH.sub.2 CH.sub.2 
OC(O)C.sub.13 H.sub.27 Cl.sup.- 
[C.sub.2 H.sub.5 ][CH.sub.3 ][C.sub.18 H.sub.37 .sup.+ NCH.sub.2 CH.sub.2 
OC(O)C.sub.14 H.sub.29 CH.sub.3 SO.sub.4.sup.- 
[C.sub.3 H.sub.7 ][C.sub.2 H.sub.5 ][C.sub.16 H.sub.33 ].sup.+ NCH.sub.2 
CH.sub.2 OC(O)C.sub.15 H.sub.31 Cl.sup.- 
[iso-C.sub.3 H.sub.7 ][CH.sub.3 ][CH.sub.18 H.sub.37 ].sup.+ NCH.sub.2 
CH.sub.2 OC(O)C.sub.15 H.sub.31 Cl.sup.- 
Similarly, in a typical synthesis of a diester variation of a 
dialkyldimethylammonium salt, an amine of the formula RN(CH.sub.2 CH.sub.2 
OH).sub.2 is esterified at both hydroxyl groups with an acid chloride of 
the formula R.sup.2 C(O)Cl, then quaternized with an alkyl halide, RX, to 
yield the desired reaction product (wherein R and R.sup.2 are as defined 
in the present application). A method for the synthesis of a preferred 
di-ester softening compound is disclosed in detail hereinafter. However, 
it will be appreciated by those skilled in the chemical arts that this 
reaction sequence allows a broad selection of compounds to be prepared. As 
illustrative, nonlimiting examples there can be mentioned the following 
(wherein all long-chain alkyl substituents are straight-chain): 
[HO-CH(CH.sub.3)CH.sub.2 ][CH.sub.3 ].sup.+ N[CH.sub.2 CH.sub.2 
OC(O)C.sub.15 H.sub.31 ].sub.2 Br.sup.- 
[C.sub.2 H.sub.5 ].sub.2.sup.+ N[CH.sub.2 CH.sub.2 OC(O)C.sub.17 H.sub.35 
].sub.2 Cl.sup.- 
[CH.sub.3 ][C.sub.2 H.sub.5 ].sup.+ N[CH.sub.2 CH.sub.2 OC(O)C.sub.13 
H.sub.27 ].sub.2 l.sup.- 
[C.sub.3 H.sub.7 ][C.sub.2 H.sub.5 ].sup.+ N[CH.sub.2 CH.sub.2 
OC(O)C.sub.15 H.sub.31 ].sub.2 SO.sub.4.sup.- CH.sub.3 
##STR8## 
Synthesis of a guaternized amine monoester softening compound 
Synthesis of the preferred biodegradable, quaternized amine monoester 
softening compound used herein is accomplished by the following two-step 
process: 
##STR9## 
0.6 mole of octadecyl ethanol methyl amine is placed in a 3-liter, 
3-necked flask equipped with a reflux condenser, argon (or nitrogen) inlet 
and two addition funnels. In one addition funnel is placed 0.4 moles of 
triethylamine and in the second addition funnel is placed 0.6 mole of 
palmitoyl chloride in a 1:1 solution with methylene chloride. Methylene 
chloride (750 mL is added to the reaction flask containing the amine and 
heated to 35.degree. C. (water bath). The triethylamine is added dropwise, 
and the temperature is raised to 40.degree.-45.degree. C. while stirring 
over one-half hour. The palmitoyl chloride/methylene chloride solution is 
added dropwise and allowed to heat at 40.degree.-45.degree. C. under inert 
atmosphere overnight (12-16 h). 
The reaction mixture is cooled to room temperature and diluted with 
chloroform (1500 mL). The chloroform solution of product is placed in a 
separatory funnel (4 L) and washed with sat. NaCl, dil. CA(OH).sub.2, 50% 
K.sub.2 CO.sub.3 (3 times)*, and, finally, sat. NaCl. The organic layer is 
collected and dried over MgSO.sub.4, filtered and solvents are removed via 
rotary evaporation. Final drying is done under high vacuum (0.25 mm Hg). 
FNT *Note: 50% K.sub.2 CO.sub.3 layer will be below chloroform layer. 
ANALYSIS 
TLC (thin layer chromoatography)**: solvent system (75% diethyl ether: 25% 
hexane) Rf=0.7. 
FNT **10.times.20 cm prescored glass plates, 250 micron silica gel; 
visualization by PMA (phosphomolybdic acid - 5% in ethanol) staining. 
IR (CCl.sub.4): 2910, 2850, 2810, 2760, 1722, 1450, 1370 cm.sup.-1 
.sup.1 H-NMR (CDCl.sub.3): .delta.2.1-2.5 (8H), 2.1 (3H), 1.20 (58H), 0.9 
(6H) ppm (relative to tetramethylsilane=0 ppm). 
##STR10## 
0.5 mole of the octadecyl palmitoyloxyethyl methyl amine, prepared in Step 
A, is placed in an autoclave sleeve along with 200-300 mL of acetonitrile 
(anhydrous). The sample is then inserted into the autoclave and purged 
three times with He (16275 mm Hg/21.4 ATM.) and once with CH.sub.3 Cl. The 
reaction is heated to 80.degree. C. under a pressure of 3604 mm Hg/4.7 
ATM. CH.sub.3 Cl and solvent is drained from the reaction mixture. The 
sample is dissolved in chloroform and solvent is removed by rotary 
evaporation, followed by drying on high vacuum (0.25 mm Hg). Both the 
C.sub.18 H.sub.37 and C.sub.15 H.sub.31 substituents in this highly 
preferred compound are n-alkyl. 
ANALYSIS 
TLC (5:1 chloroform:methanol)*: Rf=0.25. 
FNT *10.times.20 cm prescored glass plates, 250 micron silica gel; 
visualization by PMA staining. 
IR (CCl.sub.4): 2910, 2832, 1730, 1450 cm.sup.-1. 
.sup.1 H-NMR (CDCl.sub.3): .delta.4.0-4.5 (2H), 3.5 (6H), 2.0-2.7 (6H), 
1.2-1.5 (58H), 0.9 (6H) ppm (relative to tetramethylsilane=0 ppm). 
.sup.13 C-NMR (CDCl.sub.3) .delta.172.5, 65.3, 62.1, 57.4, 51.8, 33.9, 
31.8, 29.5, 28.7, 26.2, 22.8, 22.5, 14.0 (relative to tetramethylsilane=0 
ppm). 
Synthesis of a guaternized amine di-ester softening compound 
The preferred biodegradable, quaternized amine diester fabric softening 
compound used in the present invention may be synthesized using the 
following two-step process: 
##STR11## 
0.6 mole of methyl diethanol amine is placed in a 3-liter, 3-necked flask 
equipped with a reflux condenser, argon (or nitrogen) inlet and two 
addition funnels. In one addition funnel is placed 0.8 moles of 
triethylamine and in the second addition funnel is placed 1.2 moles of 
palmitoyl chloride in a 1:1 solution with methylene chloride. Methylene 
chloride (750 mL) is added to the reaction flask containing the amine and 
heated to about 35.degree. C. (water bath). The triethylamine is added 
dropwise, and the temperature is raised to 40.degree.-45.degree. C. while 
stirring over one-half hour. The palmitoyl chloride/methylene chloride 
solution is added dropwise and allowed to heat at 40.degree.-45.degree. C. 
under inert atmosphere overnight (12-16 h). 
The reaction mixture is cooled to room temperature and diluted with 
chloroform (1500 mi). The chloroform solution of product is placed in a 
separatory funnel (4 L) and washed with sat. NaCl, dil. CA(OH).sub.2, 50% 
K.sub.2 CO.sub.3 (3 times)*, and, finally, sat. NaCl. The organic layer is 
collected and dried over MgSO.sub.4 and filtered. Solvents are removed via 
rotary evaoporation. Final drying is done under high vacuum (0.25 mm Hg). 
FNT *Note: 50% K.sub.2 CO.sub.3 layer will be below chloroform layer. 
ANALYSIS 
TLC (thin layer chromatography)**: solvent system (75% diethyl ether: 25% 
hexane) Rf=0.75. 
FNT **10.times.20 cm prescored glass plates, 250 micron silica gel; 
visualization by PMA (phosphomolybdic acid--5% in ethanol) staining. 
IR (CCl.sub.4): 2920, 2850, 1735, 1450, 1155, 1100 cm.sup.-1. 
.sup.1 H-NMR (CDCl.sub.3): .delta.3.9-4.1 (2H), 2.1-2.8 (8H), 2.3 (3H), 
1.25 (52H), 1.1 (6H), 0.8 (6H) ppm (relative to tetramethylsilane=0 ppm). 
Step B: Ouaternization 
##STR12## 
0.5 moles of the methyl diethanol palmitate amine from Step A is placed in 
an autoclave sleeve along with 200-300 mL of acetonitrile (anhydous). The 
sample is then inserted into the autoclave and purged three times with He 
(16275 mm Hg/21.4 ATM.) and once with CH.sub.3 Cl. The reaction is heated 
to 80.degree. C. under a pressure of 3604 mm Hg/4.7 ATM. CH.sub.3 Cl for 
24 hours. The autoclave sleeve is then removed from the reaction mixture. 
The sample is dissolved in chloroform and solvent is removed by rotary 
evaporation, followed by drying on high vacuum (0.25 mm Hg). 
ANALYSIS 
TLC (5:1 chloroform:methanol)*: Rf=0.35. 
FNT 10.times.20 cm prescored glass plates, 250 microns silica gel; 
visualization by PMA staining. 
IR (CCl.sub.4): 2915, 2855, 1735, 1455, 1150 cm.sup.-1. 
.sup.1 H-NMR (CDCl.sub.3): .delta.4.5-5.0 (2H), 4.0-4.4 (4H), 3.7 (6H), 
2.0-2.5 (4H), 1.2-1.5 (52H), 0.9 (6H) ppm (relative to tetramethylsilane=0 
ppm). 
.sup.13 C-NMR (CDCl.sub.3); .delta.172.8, 63.5, 57.9, 52.3, 33.8, 31.8, 
31.4, 29.62 24.6, 22.6, 14.1 ppm (relative to tetramethylsilane=0 ppm). 
Although one skilled in the art can prepare the active softener ingredient 
using standard reaction chemistry, as illustrated above, various 
quaternized amine-ester compounds are also available commercially under 
the tradenames SYNPROLAM FS from ICI and REWOQUAT from REWO. A preferred 
quaternized amine-ester softening compound, i.e., the diester of 
di(hydrogenated tallow)dimethyl ammonium chloride, is available 
commercially from the Sherex Chemical Company Inc. of Dublin, Ohio under 
the tradename "Adogen DDMC". 
Wetting Agent 
The present invention contains as an essential component from 0.01% to 
about 2.0%, more preferably from about 0.01% to about 0.5% by weight, on a 
dry fiber weight basis, of a wetting agent. 
Examples of wetting agents useful in the present invention include 
polyhydroxy compounds such as glycerol and polyethylene glycols having a 
molecular weight of from about 200 to about 2000, with polyethylene 
glycols having a molecular weight of from about 200 to about 600 being 
preferred. 
A particularly preferred polyhydroxy wetting agent is polyethylene glycol 
having a molecular weight of about 400. This material is available 
commercially from the Union Carbide Company of Danbury, Conn. under the 
tradename "PEG-400". 
Other types of wetting agents useful in the present invention include 
alkoxylated alcohols. Preferably, the alkoxylated alcohol wetting agents 
are selected from the group consisting of linear alkoxylated alcohols, 
linear alkyl phenoxylated alcohols, and mixtures thereof. Most preferably, 
the alkoxylated is a linear ethoxylated alcohol or a linear alkyl 
phenoxypoly(ethyleneoxy) alcohol. 
Specific linear ethoxylated alcohols useful in the present invention are 
selected from the group consisting of the condensation products of C.sub.8 
-C.sub.18 linear fatty alcohols with from about 1 to 10 moles of ethylene 
oxide and mixtures thereof. Examples of linear ethoxylated alcohols of 
this type include Neodol 23-3 (the condensation product of C.sub.12 
-C.sub.13 linear alcohol with 3 moles ethylene exide), Neodol 91-2.5 (the 
condensation product of C.sub.9 -C.sub.11 linear alcohol with 2.5 moles 
ethylene oxide), Neodol 45-9 (the condensation product of C.sub.14 
-C.sub.15 linear alcohol with 9 moles ethylene oxide), Neodol 45-7 (the 
condensation product of C.sub.14 -C.sub.15 linear alcohol with 7 moles 
ethylene oxide), Neodol 45-4 (the condensation product of C.sub.14 
-C.sub.15 linear alcohol with 4 moles ethylene oxide), all of which are 
marketed by Shell Chemical Company. Preferred are the condensation 
products of C.sub.10 -C.sub.15 linear alcohols with from about 4 to 8 
moles of ethylene oxide, most preferred are the condensation products of 
C.sub.12 -C.sub.13 linear alcohols with 7 moles ethylene oxide (e.g., 
Neodol 23-7). 
Specific linear alkyl phenoxypoly(ethyleneoxy) alcohols useful in the 
present invention are selected from the group consisting of the 
condensation products of C.sub.8 -C.sub.18 alkyl phenoxy fatty alcohols 
with from about 1 to 10 moles of ethylene oxide and mixtures thereof. 
Examples of alkyl phenoxypoly(ethyleneoxy) alcohols of this type include 
Igepal RC-520, Igepal RC-620, Igepal DM-530, Igepal CTA-639W, all of which 
are marketed by the Rhone Poulenc Corporation (Cranbury, N.J.). Most 
preferred are Igepal RC-520 and RC-620. 
Optional Ingredients 
Other chemicals commonly used in papermaking can be added to the 
papermaking furnish so long as they do not significantly and adversely 
affect the softening, absorbency, and wet strength enhancing actions of 
the three required chemicals. 
For example, surfactants may be used to treat the tissue paper webs of the 
present invention. The level of surfactant, if used, is preferably from 
about 0.01% to about 2.0% by weight, based on the dry fiber weight of the 
tissue paper. The surfactants preferably have alkyl chains with eight or 
more carbon atoms. Exemplary anionic surfactants are linear alkyl 
sulfonates, and alkylbenzene sulfonates. Exemplary nonionic surfactants 
are alkylglycosides including alkylglycoside esters such as Crodesta.TM. 
SL-40 which is available from Croda, Inc. (New York, N.Y.); alkylglycoside 
ethers as described in U.S. Pat. No. 4.011,389, issued to W. K. Langdon, 
et al. on Mar. 8, 1977. 
Other types of chemicals which may be added include dry strength additives 
to increase the tensile strength of the tissue webs. Examples of dry 
strength additives include cationic polymers from the ACCO chemical family 
such as ACCO 771 and ACCO 514. The level of dry strength additive, if 
used, is preferably from about 0.01% to about 1.0%, by weight, based on 
the dry fiber weight of the tissue paper. 
The above listings of additional chemical additives is intended to be 
merely exemplary in nature, and are not meant to limit the scope of the 
invention. 
The papermaking furnish can be readily formed or prepared by mixing 
techniques and equipment well known to those skilled in the papermaking 
art. 
The three types of chemical ingredients described above, i.e., quaternized 
amine-ester softening compounds, wetting agents, and water soluble 
temporary wet strength resins, are preferably added to the aqueous slurry 
of papermaking fibers, or furnish in the wet end of the papermaking 
machine at some suitable point ahead of the Fourdrinier wire or sheet 
forming stage. However, applications of the above chemical ingredients 
subsequent to formation of a wet tissue web and prior to drying of the web 
to completion will also provide significant softness, absorbency, and wet 
strength benefits and are expressly included within the scope of the 
present invention. 
It has been discovered that the chemical ingredients are more effective 
when the quaternized amine-ester compound and the wetting agent are first 
premixed together before being added to the papermaking furnish. A 
preferred method, as will be described in greater detail hereinafter in 
Example 1, consists of first heating the wetting agent to a temperature of 
about 180.degree. F., and then adding the quaternized amine-ester compound 
to the hot wetting agent to form a fluidized "melt". Preferably, the molar 
ratio of the quaternized amine-ester compound to the wetting agent is 
about 1 to 1, although this ratio will vary depending upon the molecular 
weight of the particular wetting agent and/or quaternized amine-ester 
compound used. The quaternized amine-ester compound and wetting agent melt 
is then diluted to the desired concentration, and mixed to form an aqueous 
vesicle solution which is then added to the papermaking furnish. 
Since the quaternized amine-ester compounds (both mono- and di-esters) are 
somewhat labile to hydrolysis, they should be handled rather carefully 
when diluted to the desired concentrations. For example, stable diluted 
liquid compositions herein are formulated at a pH in the range of about 
2.0 to about 5.0, preferably about pH 3.0.+-.0.5. The pH can be adjusted 
by the addition of a Bronsted acid. Examples of suitable Bronsted acids 
include the inorganic mineral acids, carboxylic acids, in particular the 
low molecular weight (C.sub.1 -C.sub.5) carboxylic acids, and 
alkylsulfonic acids. Suitable inorganic acids include HCl, H.sub.2 
SO.sub.4, HNO.sub.3 and H.sub.3 PO.sub.4. Suitable organic acids include 
formic, acetic, methylsulfonic and ethylsulfonic acid. Preferred acids are 
hydrochloric and phosphoric acids. 
Without being bound by theory, it is believed that the wetting agent 
enhances the flexibility of the cellulosic fibers, improves the absorbency 
of the fibers, and acts to stabilize the quaternized amine-ester compound 
in the aqueous solution. Separately, the temporary wet strength resins are 
also diluted to the appropriate concentration and added to the papermaking 
furnish. The quaternized amine-ester/wetting agent chemical softening 
composition acts to make the paper product soft and absorbent, while the 
temporary wet strength resin insures that the resulting paper product also 
has high temporary wet strength. In other words, the present invention 
makes it possible to not only improve both the softness and absorbent rate 
of the tissue webs, but also provides a high level of temporary wet 
strength. 
The second step in the process of this invention is the depositing of the 
papermaking furnish on a foraminous surface and the third is the removing 
of the water from the furnish so deposited. Techniques and equipment which 
can be used to accomplish these two processing steps will be readily 
apparent to those skilled in the papermaking art. 
The present invention is applicable to tissue paper in general, including 
but not limited to conventionally felt-pressed tissue paper; pattern 
densified tissue paper such as exemplified in the aforementioned U.S. 
Patent by Sanford-Sisson and its progeny; and high bulk, uncompacted 
tissue paper such as exemplified by U.S. Pat. No. 3,812,000, Salvucci, 
Jr., issued May 21, 1974. The tissue paper may be of a homogenous or 
multilayered construction; and tissue paper products made therefrom may be 
of a single-ply or multi-ply construction. The tissue paper preferably has 
a basis weight of between 10 g/m.sup.2 and about 65 g/m.sup.2, and density 
of about 0.60 g/cc or less. More preferably, basis weight will be below 
about 35 g/m.sup.2 or less; and density will be about 0.30 g/cc or less. 
Most preferably, density will be between 0.04 g/cc and about 0.20 g/cc. 
Conventionally pressed tissue paper and methods for making such paper are 
known in the art. Such paper is typically made by depositing the 
papermaking furnish on a foraminous forming wire. This forming wire is 
often referred to in the art as a Fourdrinier wire. Once the furnish is 
deposited on the forming wire, it is referred to as a web. The web is 
dewatered by pressing the web and drying at elevated temperature. The 
particular techniques and typical equipment for making webs according to 
the process just described are well known to those skilled in the art. In 
a typical process, a low consistency pulp furnish is provided in a 
pressurized headbox. The headbox has an opening for delivering a thin 
deposit of pulp furnish onto the Fourdrinier wire to form a wet web. The 
web is then typically dewatered to a fiber consistency of between about 7% 
and about 25% (total web weight basis) by vacuum dewatering and further 
dried by pressing operations wherein the web is subjected to pressure 
developed by opposing mechanical members, for example, cylindrical rolls. 
The dewatered web is then further pressed and dried by a stream drum 
apparatus known in the art as a Yankee dryer. Pressure can be developed at 
the Yankee dryer by mechanical means such as an opposing cylindrical drum 
pressing against the web. Multiple Yankee dryer drums may be employed, 
whereby additional pressing is optionally incurred between the drums. The 
tissue paper structures which are formed are referred to hereinafter as 
conventional, pressed, tissue paper structures. Such sheets are considered 
to be compacted since the web is subjected to substantial mechanical 
compressional forces while the fibers are moist and are then dried while 
in a compressed state. 
Pattern densified tissue paper is characterized by having a relatively high 
bulk field of relatively low fiber density and an array of densified zones 
of relatively high fiber density. The high bulk field is alternatively 
characterized as a field of pillow regions. The densified zones are 
alternatively referred to as knuckle regions. The densified zones may be 
discretely spaced within the high bulk field or may be interconnected 
within the high bulk field. Preferred processes for making pattern 
densified tissue webs are disclosed in U.S. Pat. No. 3,301,746, issued to 
Sanford and Sisson on Jan. 31, 1967, U.S. Pat. No. 3,974,025, issued to 
Peter G. Ayers on Aug. 10, 1976, and U.S. Pat. No. 4,191,609, issued to 
Paul D. Trokhan on Mar. 4, 1980, and U.S. Pat. No. 4,637,859, issued to 
Paul D. Trokhan on Jan. 20, 1987; all of which are incorporated herein by 
reference. 
In general, pattern densified webs are preferably prepared by depositing a 
papermaking furnish on a foraminous forming wire such as a Fourdrinier 
wire to form a wet web and then juxtaposing the web against an array of 
supports. The web is pressed against the array of supports, thereby 
resulting in densified zones in the web at the locations geographically 
corresponding to the points of contact between the array of supports and 
the wet web. The remainder of the web not compressed during this operation 
is referred to as the high bulk field. This high bulk field can be further 
dedensified by application of fluid pressure, such as with a vacuum type 
device or a blow-through dryer, or by mechanically pressing the web 
against the array of supports. The web is dewatered, and optionally 
predried, in such a manner so as to substantially avoid compression of the 
high bulk field. This is preferably accomplished by fluid pressure, such 
as with a vacuum type device or blow-through dryer, or alternately by 
mechanically pressing the web against an array of supports wherein the 
high bulk field is not compressed. The operations of dewatering, optional 
predrying and formation of the densified zones may be integrated or 
partially integrated to reduce the total number of processing steps 
performed. Subsequent to formation of the densified zones, dewatering, and 
optional predrying, the web is dried to completion, preferably still 
avoiding mechanical pressing. Preferably, from about 8% to about 55% of 
the tissue paper surface comprises densified knuckles having a relative 
density of at least 125% of the density of the high bulk field. 
The array of supports is preferably an imprinting carrier fabric having a 
patterned placement of knuckles which operate as the array of supports 
which facilitate the formation of the densified zones upon application of 
pressure. The pattern of knuckles constitutes the array of supports 
previously referred to. Imprinting carrier fabrics are disclosed in U.S. 
Pat. No. 3,301,746, Sanford and Sisson, issued Jan. 31, 1967, U.S. Pat. 
No. 3,821,068, Salvucci, Jr. et al., issued May 21, 1974, U.S. Pat. No. 
3,974,025, Ayers, issued Aug. 10, 1976, U.S. Pat. No. 3,573,164, Friedberg 
et al., issued Mar. 30, 1971, U.S. Pat. No. 3,473,576, Amneus, issued Oct. 
21, 1969, U.S. Pat. No. 4,239,065, Trokhan, issued Dec. 16, 1980, and U.S. 
Pat. No. 4,528,239, Trokhan, issued Jul. 9, 1985, all of which are 
incorporated herein by reference. 
Preferably, the furnish is first formed into a wet web on a foraminous 
forming carrier, such as a Fourdrinier wire. The web is dewatered and 
transferred to an imprinting fabric. The furnish may alternately be 
initially deposited on a foraminous supporting carrier which also operates 
as an imprinting fabric. Once formed, the wet web is dewatered and, 
preferably, thermally predried to a selected fiber consistency of between 
about 40% and about 80%. Dewatering is preferably performed with suction 
boxes or other vacuum devices or with blow-through dryers. The knuckle 
imprint of the imprinting fabric is impressed in the web as discussed 
above, prior to drying the web to completion. One method for accomplishing 
this is through application of mechanical pressure. This can be done, for 
example, by pressing a nip roll which supports the imprinting fabric 
against the face of a drying drum, such as a Yankee dryer, wherein the web 
is disposed between the nip roll and drying drum. Also, preferably, the 
web is molded against the imprinting fabric prior to completion of drying 
by application of fluid pressure with a vacuum device such as a suction 
box, or with a blow-through dryer. Fluid pressure may be applied to induce 
impression of densified zones during initial dewatering, in a separate, 
subsequent process stage, or a combination thereof. 
Uncompacted, nonpattern-densified tissue paper structures are described in 
U.S. Pat. No. 3,812,000 issued to Joseph L. Salvucci, Jr. and Peter N. 
Yiannos on May 21, 1974 and U.S. Pat. No. 4,208,459, issued to Henry E. 
Becker, Albert L. McConnell, and Richard Schutte on Jun. 17, 1980, both of 
which are incorporated herein by reference. In general, uncompacted, 
nonpattern-densified tissue paper structures are prepared by depositing a 
papermaking furnish on a foraminous forming wire such as a Fourdrinier 
wire to form a wet web, draining the web and removing additional water 
without mechanical compression until the web has a fiber consistency of at 
least 80%, and creping the web. Water is removed from the web by vacuum 
dewatering and thermal drying. The resulting structure is a soft but weak 
high bulk sheet of relatively uncompacted fibers. Bonding material is 
preferably applied to portions of the web prior to creping. 
Compacted non-pattern-densified tissue structures are commonly known in the 
art as conventional tissue structures. In general, compacted, 
non-pattern-densified tissue paper structures are prepared by depositing a 
papermaking furnish on a foraminous wire such as a Fourdrinier wire to 
form a wet web, draining the web and removing additional water with the 
aid of a uniform mechanical compaction (pressing) until the web has a 
consistency of 25-50%, transferring the web to a thermal dryer such as a 
Yankee and creping the web. Overall, water is removed from the web by 
vacuum, mechanical pressing and thermal means. The resulting structure is 
strong and generally of singular density, but very low in bulk, absorbency 
and in softness. 
The tissue paper web of this invention can be used in any application where 
soft, absorbent tissue paper webs with high temporary wet strength are 
required. One particularly advantageous use of the tissue paper web of 
this invention is in sanitary tissue products (e.g., toilet paper). 
Analysis of the amount of treatment chemicals herein retained on tissue 
paper webs can be performed by any method accepted in the applicable art. 
For example, the level of the quaternized amine-ester compound, such as an 
ester variation of a dialkyldimethylammonium salt, retained by the tissue 
paper can be determined by solvent extraction of the compound by an 
organic solvent followed by an anionic/cationic titration using Dimidium 
Bromide as indicator; the level of the wetting agent, such as PEG-400, can 
be determined by extraction in an organic solvent followed by gas 
chromatography to determine the level of PEG-400 in the extract; the level 
of temporary wet strength resin such as a temporary wet strength resin 
with a nitrogen moiety (e.g., as described in U.S. Pat. No. 4,981,557, D. 
W. Bjorkquist issued Jan. 1, 1991) resin can be determined by subtraction 
from the total nitrogen level obtained via the Nitrogen Analyzer, the 
amount of quaternized amine-ester compound level, determined by the above 
titration method. These methods are exemplary, and are not meant to 
exclude other methods which may be useful for determining levels of 
particular components retained by the tissue paper. 
Hydrophilicity of tissue paper refers, in general, to the propensity of the 
tissue paper to be wetted with water. Hydrophilicity of tissue paper may 
be somewhat quantified by determining the period of time required for dry 
tissue paper to become completely wetted with water. This period of time 
is referred to as "wetting time." In order to provide a consistent and 
repeatable test for wetting time, the following procedure may be used for 
wetting time determinations: first, a conditioned sample unit sheet (the 
environmental conditions for testing of paper samples are 
23.degree..+-.1.degree. C. and 50.+-.2% RH. as specified in TAPPI Method T 
402), approximately 43/8 inch.times.43/4 inch (about 11.1 cm.times.12 cm) 
of tissue paper structure is provided; second, the sheet is folded into 
four (4) juxtaposed quarters, and then crumpled into a ball approximately 
0.75 inches (about 1.9 cm) to about 1 inch (about 2.5 cm) in diameter; 
third, the balled sheet is placed on the surface of a body of distilled 
water at 23.degree..+-.1.degree. C. and a timer is simultaneously 
started; fourth, the timer is stopped and read when wetting of the balled 
sheet is completed. Complete wetting is observed visually. 
The preferred hydrophilicity of tissue paper depends upon its intended end 
use. It is desirable for tissue paper used in a variety of applications, 
e.g., toilet paper, to completely wet in a relatively short period of time 
to prevent clogging once the toilet is flushed. Preferably, wetting time 
is 2 minutes or less. More preferably, wetting time is 30 seconds or less. 
Most preferably, wetting time is 10 seconds or less. 
Hydrophilicity characters of tissue paper embodiments of the present 
invention may, of course, be determined immediately after manufacture. 
However, substantial increases in hydrophobicity may occur during the 
first two weeks after the tissue paper is made: i.e., after the paper has 
aged two (2) weeks following its manufacture. Thus, the above stated 
wetting times are preferably measured at the end of such two week period. 
Accordingly, wetting times measured at the end of a two week aging period 
at room temperature are referred to as "two week wetting times." 
The density of tissue paper, as that term is used herein, is the average 
density calculated as the basis weight of that paper divided by the 
caliper, with the appropriate unit conversions incorporated therein. 
Caliper of the tissue paper, as used herein, is the thickness of the paper 
when subjected to a compressive load of 95 g/in.sup.2 (14.7 g/cm.sup.2). 
The following examples illustrate the practice of the present invention but 
is not intended to be limiting thereof. 
EXAMPLE 1 
The purpose of this example is to illustrate one method that can be used to 
make soft, absorbent and high temporary wet strength tissue fibrous 
structure treated with a mixture of Diester Dihydrogenated Tallow Dimethyl 
Ammonium Chloride (DEDTDMAC)(i.e., ADOGEN DDMC from the Sherex Chemical 
Company) and a polyethylene glycol wetting agent (i.e., PEG-400 from the 
Union Carbide Company) in the presence of a temporary wet strength resin 
in accordance with the present invention. 
A pilot scale Fourdrinier papermaking machine is used in the practice of 
the present invention. First, a 1% solution of the chemical softener 
composition containing DEDTDMAC and PEG-400 is prepared according to the 
following procedure: 1 . An equivalent molar concentration of DEDTDMAC and 
PEG-400 is weighed; 2. PEG is heated up to about 180.degree. F.; 3. 
DEDTDMAC is dissolved into PEG to form a melted solution; 4. Shear stress 
is applied to form a homogeneous mixture of DEDTDMAC in PEG; 5. The pH of 
the dilution water is adjusted to about 3 by the addition of hydrochloric 
acid. 6. The dilution water is then heated up to about 180.degree. F.; 7. 
The melted mixture of DEDTDMAC/PEG-400 is diluted to a 1% solution; and 8. 
Shear stress is applied to form an aqueous solution containing a vesicle 
suspension of the DEDTDMAC/PEG-400 mixture. 
Second, a 3% by weight aqueous slurry of NSK is made up in a conventional 
re-pulper. The NSK slurry is refined gently and a 2% solution of the 
temporary wet strength resin (as described in U.S. Pat. No. 4,981,557, D. 
W. Bjorkquist issued Jan. 1, 1991) is added to the NSK stock pipe at a 
rate of 0.75% by weight of the dry fibers. The adsorption of the temporary 
wet strength resin onto NSK fibers is enhanced via an in-line mixer. The 
NSK slurry is diluted to about 0.2% consistency at the fan pump. 
Third, a 3% by weight aqueous slurry of Eucalyptus fibers is made up in a 
conventional re-pulper. A 1% solution of the chemical softener mixture is 
added to the Eucalyptus stock pipe before the stock pump at a rate of 0.2% 
by weight of the dry fibers. The adsorption of the chemical softener 
mixture to the Eucalyptus fibers can be enhanced via an in-line mixer. The 
Eucalyptus slurry is diluted to about 0.2% consistency at the fan pump. 
The treated furnish mixture (30% of NSK/70% of Eucalyptus) is blended in 
the head box and deposited onto a Fourdrinier wire to form an embryonic 
web. Dewatering occurs through the Fourdrinier wire and is assisted by a 
deflector and vacuum boxes. The Fourdrinier wire is of a 5-shed, satin 
weave configuration having 87 machine-direction and 76 
cross-machine-direction monofilaments per inch, respectively. The 
embryonic wet web is transferred from the Fourdrinier wire, at a fiber 
consistency of about 15% at the point of transfer, to a photo-polymer belt 
having 562 Linear Idaho cells per square inch, 32 percent of knuckle areas 
and 6 mils of photo-polymer depth. Further dewatering is accomplished by 
vacuum assisted drainage until the web has a fiber consistency of about 
28%. The patterned web is predried by air blow-through to a fiber 
consistency of about 65% by weight. The web is then adhered to the surface 
of a Yankee dryer with a sprayed creping adhesive comprising 0.25% aqueous 
solution of Polyvinyl Alcohol (PVA). The fiber consistency is increased to 
an estimated 98% before the dry creping the web with a doctor blade. The 
doctor blade has a bevel angle of about 24 degrees and is positioned with 
respect to the Yankee dryer to provide an impact angle of about 83 
degrees; the Yankee dryer is operated at about 800 fpm (feet per minute) 
(about 244 meters per minute). The dry web is formed into roll at a speed 
of 700 fpm (214 meters per minute). 
Two plies of the web are formed into tissue paper products and laminating 
together using conventional ply bonding techniques well known in the 
papermaking industry. The tissue paper has about 23 lbs./1000 sq. ft. 
basis weight, contains about 0.05% of DEDTDMAC, 0.05% PEG-400, and about 
0.5% of the temporary wet strength resin. Importantly, the resulting 
tissue paper is soft, absorbent and has high temporary wet strength. 
EXAMPLE 2 
The purpose of this example is to illustrate one method that can be used to 
make soft, absorbent and high temporary wet strength tissue fibrous 
structure treated with a mixture of Diester Dihydrogenated Tallow Dimethyl 
Ammonium Chloride (DEDTDMAC) and a linear ethoxylated alcohol wetting 
agent (i.e., Neodol 23-7 from the Shell Chemical Company) in the presence 
of a temporary wet strength resin in accordance with the present 
invention. 
The tissue structure is produced in accordance with the hereinbefore 
described process of Example 1 with the exception that an equivalent molar 
concentration of Neodol 23-7 is used as the wetting agent instead of 
PEG-400. The resulting tissue paper contains about 0.05% DEDTDMAC, 0.05% 
Neodol 23-7, and about 0.5% of the temporary wet strength. Importantly, 
the tissue paper is soft, absorbent and has high temporary wet strength. 
EXAMPLE 3 
The purpose of this example is to illustrate one method that can be used to 
make soft, absorbent and high temporary wet strength tissue fibrous 
structure treated with a mixture of Diester Dihydrogenated Tallow Dimethyl 
Ammonium Chloride (DEDTDMAC) and a linear alkylphenoxypoly(ethyleneoxy) 
alcohol (Igepal RC-520) in the presence of a temporary wet strength resin 
in accordance with the present invention. 
The tissue structure is produced in accordance with the hereinbefore 
described process of Example 1 with the exception that an equivalent molar 
concentration of Igepal RC-520 (a linear dodecylphenoxypoly(ethyleneoxy) 
alcohol with about 5 moles ethylene oxide per mole of dodecylphenol) is 
used as the wetting agent instead of PEG-400. The resulting tissue paper 
contains about 0.05% DEDTDMAC, 0.05% Igepal RC-520, and about 0.5% of the 
temporary wet strength. Importantly, the tissue paper is soft, absorbent 
and has high temporary wet strength.