Field of the Invention
[0001] The present invention relates to sheets of material preferably wet wipes which are
provided with an improved perforation configuration, which is easily visible to the
consumer and which allows the wet wipes to be easily separated from oneanother whilst
not compromising on strength.
Background of the Invention
[0002] Wet wipes are typically premoistened, disposable towelettes which may be utilised
in a variety of applications both domestic and industrial and perform a variety of
functions. Wet wipes are typically used to wipe surfaces both animate and inanimate,
and may provide numerous benefits such as cleaning, cleansing, disinfecting, and skin
care benefits.
[0003] One particular application is the use of wet wipes for wiping parts of the human
body particularly when wash water is not available, for example when travelling. Wipes
are commonly used for human cleansing and wiping such as face and hand cleansing and
anal, perineal and genital cleansing for example as intimate hygiene wipes such as
feminine wet wipes. Wet wipes may also be used for application of substances to the
body including removing and applying of make-up, skin conditioners and medications.
Another application of wipes is during diaper changes and also for the treatment of
adult and baby dermatitis partly caused by the use of diapers and incontinence devices.
In addition wet wipes are also applicable for wiping and or cleaning other surfaces
or for the application of compositions to surfaces, for example kitchen and bathroom
surfaces, eyeglasses, shoes and surfaces which require cleaning in industry for example
surfaces of machinery or automobiles. Wet wipes also include articles used for the
cleaning or grooming of pets.
[0004] Wet wipes are commonly constructed from combinations of synthetic and natural fibres,
such as polyolefin fibres, viscose fibres and cotton fibres, which are generally moistened
with an aqueous composition which contains amongst others surfactants, preservatives,
oils and scents. The wet wipes are then typically provided in a folded stacked configuration
within a covered container such as a tub-like container having a lid. Alternatively,
the wipes may be provided in tub containers having a dispensing aperture. In both
cases this allows easy transportation and storage of the wipes. Typically the wipes
are packaged in a plastic foil in order to protect the wet wipes prior to use.
[0005] In order to aid dispensing and to allow the consumer to select the desired size of
wipe it is highly desirable to provide the wipes with perforations. The use of perforations
is well known in the field of paper, tissue and towels. For example, US 5 704 566
discloses a roll of paper towelling to be dispensed from a dispenser which may be
separated into towelling segments by pulling along perforated tear lines. The perforated
tear lines comprise a plurality of slits which are longer towards the side edges of
the paper than in the middle, to aid dispensing.
[0006] Similarly DE 27 06 234 discloses the use of perforated lines of variegated holes
formed in a paper sheet, the diameter of which increases towards the edge of the paper
so as to facilitate tearing of the paper by one hand.
[0007] The use of perforations for wet wipes is particularly advantageous not only in terms
of dispensing, but also in allowing the consumer to select the length or amount of
wet wipe material required to carry out a particular clearing activity.
[0008] Thus for small and easy cleaning activities just one wipe can be selected, whilst
for larger and dirty cleaning activities a number of wipes can be used. Thus it is
not only important that the consumer can easily dispense the size of wipe that is
required, it is also equally important that the perforations are strong enough such
that they do not break or tear within a larger wipe during the cleaning process. This
problem of perforation strength is further exacerbated upon storage of the wet wipes
which has been found to generally weaken the perforation.
[0009] In addition another important factor with respect to the convenient usage of such
wipes, is that the consumer can readily identify the location of the perforations
in the wipe substrate. The visibility of the perforations is related to the length
of the perforation or slit in the substrate; larger perforations or slits providing
easy recognition by the consumer. However a problem with such larger perforations
is that the strength of the perforations is further reduced, which is as discussed
above highly undesirable. This problem is yet further exacerbated by certain dispensing
methods. For example methods which result in continuous dispensing through a container
orifice whereby mechanical friction is utilised to dispense and separate the wipes.
[0010] It is therefore desirable to provide a wet wipe stacking configuration which is suitable
for multiple applications such as baby wipes and hard surface cleaning wipes which
are strong, soft, absorbent and provide improved cleaning. It is further desirable
to provide wet wipes whereby the wipe substrate is provide with perforated tear lines
that are readily visible so that the consumer can select the desired length of wipe
required and easily separate the wipes from oneanother, whilst providing sufficient
strength so that the perforation within the wipe does not tear or break during use.
Summary of the Invention
[0011] The present invention hence relates to a sheet of material, preferably a wet wipe
for wiping parts of the human body such as baby wipes and other inanimate surfaces.
In particular, the present invention relates to a sheet of material (1) such as a
wet wipe, wherein said sheet of material comprises at least one transverse perforation
line (20), said transverse perforation line (20), having at least one repeating perforation
pattern (21), characterised in that each of said repeating patterns (21) has at least
one primary perforation slit (22), at least one secondary perforation slit (23) and
at least two bonded areas (24), wherein the length ratio of one of said primary perforation
slits (22) to one of said secondary perforation slits (23) is from 100:1 to 1.5:1
and wherein the ratio of the total length of said bonded areas (24) to the total length
of said primary (22) and secondary (23) perforation slits of said perforation line
is from 1:1 to 1:6.
Detailed Description of the Invention
Brief description of the figures
[0012]
- Figure 1a:
- Is a plan view of a sheet material, e.g. a wet wipe showing the perforation line of
the present invention.
- Figure 1b:
- Is a cross sectional side view of the sheet material of figure 1, comprising perforation
line according to the present invention.
- Figure 2:
- Is a partial plan view of a sheet of material having the preferred perforation line
of the present invention.
[0013] According to the present invention the sheet of material comprises a substrate which
is preferably coated or impregnated with a liquid composition. The sheet of material
may be woven or nonwoven, foam, sponge, battings, balls, puffs, films, or tissue paper,
most preferably a nonwoven and may be composed or natural or synthetic fibres or mixtures
thereof. Preferably, the fibre compositions are a mixed of hydrophilic fibre material
such as viscose, cotton, or flax and a hydrophobic fibre material such as polyethylene
tetraphthalate (PET) or polypropylene (PP) in a ratio of 10%-90% hydrophilic and 90%-10%
hydrophobic material by weight. Particularly preferred compositions are 50% viscose,
50%PP; and 50% viscose, 50 % PET; and 70% cellulose, 15% PET and 15% latex. The sheet
of material preferably has a basis weight of at least 20 gm
-2 and preferably less than 150gm
-2, and most preferably the base weight is in the range of 20 gm
-2 to 100 gm
-2, more preferably from 50 gm
-2 to 95 gm
-2. The sheet of material may have any caliper. Typically, when the sheet of material
is made by an air laying process, the average sheet of material caliper is less than
1.0 mm. More preferably the average caliper of the sheet of material is from 0.1 mm
to 0.9 mm. The sheet of material caliper is measured according to standard EDANA non
woven industry methodology, reference method # 30.4-89.
[0014] In addition to the fibers used to make the sheet of material, the sheet of material
can have other components or materials added thereto as known in the art. The types
of additives desirable will be dependent upon the particular end use of the substrate
contemplated. For example, in wet wipe products such as moist toilet paper, paper
towels, facial tissues, baby wipes and other similar air laid products, high wet strength
is a desirable attribute. Thus, it is often desirable particularly for cellulose based
materials to add chemical substances known in the art as wet strength resins. A general
dissertation on the types of wet strength resins utilised in the paper art 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). Particularly preferred
resins are polyamide-epichlorohydrin, polyacrylamides, styrene-butiene latexes, dialdehyde
starch and mixtures thereof. In addition to wet strength additives, it can also be
desirable to include certain dry strength and lint control additives known in the
art such as starch binders. Furthermore, the material may also comprise agents to
improve the optical characteristics of the material such as opacifying agents, for
example titanium dioxide.
[0015] According to the present invention the sheet may be produced by any methods known
in the art. For example nonwoven material substrates can be formed by dry forming
techniques such as air-laying or wet laying such as on a paper making machine. Other
nonwoven manufacturing techniques such as melt blown, spun bonded, needle punched
and spun laced methods may also be used. A preferred method is air laying.
[0016] According to the present invention, the sheets of material are provided in a stacked
configuration which may comprise any number of sheets. Typically, the stack comprises
from 3 to 150, more preferably from 5 to 100, most preferably from 10 to 60 of sheets
of material. Moreover the sheets may be provide in any configuration folded or unfolded.
Most preferably the wipes are stacked in a folded configuration. In an alternative
embodiment the sheet of material may be provided as a roll, which comprises a continuous
material providing individual sheets connected end to end by perforation lines according
to the present invention. The present invention will now be described with reference
to the preferred embodiment of the present invention namely wet wipes. However the
description is equally applicable to the alternative sheet materials and configurations.
[0017] Each folded wipe 1 extends lengthwise in the machine direction from a first, leading
end edge 2, to a second, trailing end edge 3. The folded webs also have side edges
4 and 5 which extend lengthwise from the first leading end edge 2 to the second trailing
end edge 3. Each folded wipe 1 can include a first panel fold 6 which is generally
parallel to the leading edge 2, and which is generally perpendicular to the side edges
4, 5. The first panel fold 6 is spaced lengthwise from the leading edge 2 to provide
a leading edge panel 9 extending between the first panel fold 6 and the leading edge
2. As used herein a panel is a portion of the wipe extending between two folds, or
between a fold and an edge end.
[0018] The folded wipe can also include a second panel fold 7, and a first central panel
8, and a trailing edge panel 10. The second panel fold 7 is generally parallel to,
and spaced lengthwise from, the first panel fold 6. The first central panel 8 is joined
to the leading edge panel 9, at the first panel fold 6, and extends between the first
panel fold 6 and the second panel fold 7.
[0019] The trailing edge panel 10 is joined to the first central panel 8 at the second panel
fold 7. The trailing edge panel 10 extends between the second panel fold 7 and the
trailing end edge 3. The wipe is folded at the first and second panel folds 6 and
7 to provide the leading edge panel 9, first central panel 8, and trailing edge panel
10, in a Z-fold configuration, as best seen in Figure 3a. In the Z-fold configuration,
panel 9 is adjacent to and overlies a portion of panel 8, and panel 10 is adjacent
to and underlies a portion of panel 8. However, other folding configurations such
as C folds or J folds configurations having more or less panels are equally applicable.
[0020] Furthermore in addition to the panels described herein above, the wipe may have additional
panels. In particular, the leading edge panel and or the trailing edge panel may also
be provided with an additional fold so as to provide a leading edge panel lip or a
trailing edge panel lip. Such a lip is formed by providing the leading edge panel
or the trailing edge panel with a panel lip fold which is adjacent to and spaced from
the leading or trailing edge of the folded substrate to provide a lip extending between
the panel lip fold and the end edge. The panel lip fold may be folded onto the lower
surface of the leading edge panel such that the leading end edge is below the leading
edge end panel. This configuration is particularly beneficial in facilitating grasping
of the edge. Alternatively, the leading edge panel may be folded such that the leading
end edge rests on the upper surface of the leading edge panel. The lip may also be
positioned on the upper or lower surface of the trailing edge panel.
[0021] According to the present invention, the overall dimensions of the substrate material
is dependent on the intended application of the wipe and can be selected accordingly.
In one non limiting, illustrative example wherein the wipe may be utilised as a hard
surface cleaning wipe, each folded wipe 1 can have an unfolded length of from 10 cm
to 40 cm as measured lengthwise from the leading end edge 2 to the trailing end edge
3 and a width of from 10cm to 25cm. For each folded wipe 1, the lengths of the leading
edge panel 9 and trailing edge panel 10 can be from 2 cm to 7 cm. In a preferred embodiment
the spacing between the first panel fold 6 and the leading end edge 2 and the second
panel fold 7 and the trailing edge 3, is preferably from 3 cm to 6. The spacing between
the first panel fold 6 and the third panel fold 12 and the second panel fold 7 and
the third panel fold 12 are preferably from 3 cm to 12 cm, and more preferably between
about 8 cm and 12 cm.
[0022] According to the present invention the wet wipes are provided, with at least one
transverse perforation lines (20). The perforation lines comprise perforated slits
or cuts joined by wet substrate material in-between each perforated slit, herein after
referred to as bonded area. The transverse perforation lines are provided typically
at regular intervals. For the unlimiting example described hereinabove this will be
from 9 cm to 20 cm, preferably from 12 cm to 16 cm.
[0023] It has now been found that the provision of the perforation line (20) with at least
one repeating pattern (21) as defined herein provides the wet wipe stack with easily
visible perforations which are strong.
[0024] Accordingly, the perforation lines (20) comprise at least one repeat pattern (21).
According to the preferred embodiment of the present invention the perforation line
(20) comprises at least one repeating pattern (21). However the perforation line (20)
may comprise any number of repeating patterns. Each of said repeating pattern (21)
comprises at least one primary perforation slit (22) and at least one, preferably
from 1 to 20, more preferably from 2 to 10, secondary perforation slits (23). The
exact number utilised can be readily selected by the skilled person depending on the
material substrate type and use intended provided that certain parameters are meet.
The length ratio between the primary (22) and the secondary (23) perforations slits
from 100:1 to 1.5:1, preferably from 50:1 to 2:1, more preferably from 25:1 to 2:1,
most preferably from 10:1 to 3:1. The presence of a primary slit (22) which is substantially
longer than the secondary slit (23) provides an easily recognisable means for the
consumer to locate the perforation line along the wipe. The perforation slits whether
primary (22) or secondary (23) are separated from one another by the wet wipe substrate
material. This substrate material is referred to as bonded area (24). Typically the
ratio of the length of one of the bonded areas (24) to the length of one of the secondary
perforation slits (23) is from 10:1 to 1:10 preferably from 5:1 to 1:5, most preferably
1:2 to 1:1. The exact number utilised can be readily selected by the skilled person
depending on the material substrate type and use intended provided that certain parameters
are meet. Typically each perforation line (20) comprises at least one repeating pattern
(21), which is repeated at least once, preferably from 1 to 50, more preferably from
5 to 25, most preferably from 10 to 20 times, depending upon the length of the repeating
pattern and the width of the wipe.
[0025] It has been identified that in order to ensure the desired tensile strength of the
wet wipes, the ratio of the total length of the bonded area (24) to the total length
of the primary (22) and secondary (23) perforation slit along the perforation line
(20) is from 1:1 to 1:6, preferably from 1:1.5 to 1:4, more preferably from 1:2 to
1:3.5.
[0026] Typically the ratio of the width of the wipe to the length of the total bonded area
(24) along the perforation line (20) is from 10:1 to 1:10, preferably from 5:1 to
3:1.
[0027] For the wet wipe of the unlimited example described herein above the length of each
primary perforation slit (22) is from 3 mm to 10 mm, preferably from 3 mm to 8 mm,
more preferably from 3.5 mm to 6.5 mm. The length of each secondary perforation slit
(23) is from 0.5 mm to 2.5 mm, preferably from 1 mm to 2 mm. The length of each bonded
area (24) is from 0.5 mm to 10 mm, preferably from 0.5 mm to 3 mm, more preferably
from 0.5 mm to 1.5 mm.
[0028] In order to provide the desired tensile strength, the perforation lines should preferably
exhibit a tensile strength of at least 0.7N/inch (0.28N/cm) to 5N/inch (1.97N/cm),
more preferably from 1N/inch (0.39N/cm) to 4.5N/inch (1.77N/cm), most preferably from
1.8N/inch (0.70N/cm) to 4.0N/inch (1.57N/cm) as described in the EDANA 30 test method
camed out on the material within 24 hours of manufacture.
[0029] According to the present invention, the substrate material of the wipes is typically
impregnated or coated with a liquid composition. The composition may be aqueous, alcohol
based or an emulsion, either a water-in-oil or a oil-in-water or a multiple emulsion,
preferably the emulsion is a oil-in-water emulsion.
[0030] Typically, the composition will comprise from 2% to 50% by weight of said composition
of actives and from 50% to 98% water, preferably de-ionised or distilled. Of the active
component, preferably 2% to 20% are present in the oil phase and the remainder are
present in the aqueous phase.
[0031] The liquid composition can provide a number of different benefits when released.
For example, in wet-like cleaning wipes for perianal cleaning the water component
is released and thereby provides the primary cleansing action for these wipes.
[0032] In a preferred embodiment of the present invention the liquid composition (preferably
comprising water as a major constituent) comprises a disinfecting component comprising
an antimicrobial compound, preferably an essential oil or an active thereof, and a
bleach, preferably a peroxygen bleach. Disinfecting wipes comprising such a liquid
composition provide effective disinfecting performance on a surface while being safe
to the surface treated.
[0033] By "effective disinfecting performance" it is meant herein that the disinfecting
wipes of the present invention allow significant reduction in the amount of bacteria
on an infected surface. Indeed, effective disinfecting may be obtained on various
micro-organisms including Gram positive bacteria like Staphylococcus aureus, and Gram
negative bacteria like Pseudomonas aeruginosa, as well as on more resistant micro-organisms
like fungi (e.g., Candida albicans) present on infected surfaces.
[0034] Another advantage of the disinfecting wipes according to the present invention is
that besides the disinfecting properties delivered, good cleaning is also provided
as the disinfecting polar phase may further comprise surfactants and/or solvents.
[0035] An essential element of such disinfecting liquid compositions is an antimicrobial
compound typically selected from the group consisting of an essential oil and an active
thereof, paraben (e.g., methyl paraben, ethyl paraben), glutaraldehyde and mixtures
thereof. Essential oils or actives thereof are the preferred antimicrobial compounds
to be used herein.
[0036] Suitable essential oils or actives thereof to be used herein are those essential
oils which exhibit antimicrobial activity and more particularly antibacterial activity.
By "actives of essential oils" it is meant herein any ingredient of essential oils
that exhibits antimicrobial/antibacterial activity. A further advantage of said essential
oils and actives hereof is that they impart pleasant odour to the disinfecting wipes
according to the present invention without the need of adding a perfume. Indeed, the
disinfecting wipes according to the present invention deliver not only excellent disinfecting
performance on infected surfaces but also good scent.
[0037] Such essential oils include, but are not limited to, those obtained from thyme, lemongrass,
citrus, lemons, oranges, anise, clove, aniseed, cinnamon, geranium, roses, mint, lavender,
citronella, eucalyptus, peppermint, camphor, sandalwood and cedar and mixtures thereof.
Actives of essential oils to be used herein include, but are not limited to, thymol
(present for example in thyme), eugenol (present for example in cinnamon and clove),
menthol (present for example in mint), geraniol (present for example in geranium and
rose), verbenone (present for example in vervain), eucalyptol and pinocarvone (present
in eucalyptus), cedrol (present for example in cedar), anethol (present for example
in anise), carvacrol, hinokitiol, berberine, terpineol, limonene, methyl salycilate
and mixtures thereof. Preferred actives of essential oils to be used herein are thymol,
eugenol, verbenone, eucalyptol, carvacrol, limonene and/or geraniol. Thymol may be
commercially available for example from Aldrich, eugenol may be commercially available
for example from Sigma, Systems - Bioindustries (SBI) - Manheimer Inc.
[0038] Typically, the antimicrobial compound or mixtures thereof will be present in the
liquid composition at a level of from 0.001 % to 5%, preferably from 0.001 % to 3%,
more preferably from 0.005% to 1 %, by weight of liquid composition.
[0039] An important element of the internal disinfecting polar phase is a bleach or mixtures
thereof. Any bleach known to those skilled in the art may be suitable to be used herein
including any chlorine bleach as well as any peroxygen bleach. The presence of the
bleach, preferably the peroxygen bleach, in the disinfecting wipes of the present
invention contribute to the disinfecting properties of the wipes.
[0040] Suitable chlorine bleaches to be used herein include any compound capable of releasing
chlorine when said compound is in contact with water. Suitable chlorine bleaches include
alkali metal dichloroisocyanurates as well as alkali metal hypohalites like hypochlorite
and/or hypobromite. Preferred chlorine bleaches are alkali metal hypochlorites. Various
forms of alkali metal hypochlorite are commercially available, for instance sodium
hypochlorite.
[0041] Preferred bleaches for use herein are peroxygen bleaches, more particularly hydrogen
peroxide, or a water soluble source thereof, or mixtures thereof. Hydrogen peroxide
is particularly preferred.
[0042] Peroxygen bleaches like hydrogen peroxide are preferred herein as they are generally
well accepted from an environmental point of view. For example the decomposition products
of hydrogen peroxide are oxygen and water.
[0043] As used herein, a hydrogen peroxide source refers to any compound which produces
perhydroxyl ions when said compound is in contact with water. Suitable water-soluble
sources of hydrogen peroxide for use herein include percarbonates, persilicates, persulphates
such as monopersulfate, perborates, peroxyacids such as diperoxydodecandioic acid
(DPDA), magnesium perphthalic acid, dialkylperoxides, diacylperoxides, performed percarboxylic
acids, organic and inorganic peroxides and/or hydroperoxides and mixtures thereof.
[0044] Typically, the bleach or mixtures thereof is present at a level of from 0.001% to
15% by weight of the liquid composition, preferably from 0.001% to 5%, and more preferably
from 0.005% to 2%.
[0045] The liquid composition may further comprise a detersive surfactant or a mixture thereof.
Typically, the surfactant or mixtures thereof is present at a level of from 0.001
% to 40% by weight of the total internal polar phase, preferably from 0.01 % to 10%
and more preferably from 0.05% to 2%.
[0046] Suitable detersive surfactants to be used in the present invention include any surfactant
known to those skilled in the art like nonionic, anionic, cationic, amphoteric and/or
zwitterionic surfactants. Preferred detersive surfactants to be used herein are the
amphoteric and/or zwitterionic surfactants.
[0047] Suitable amphoteric detersive surfactants to be used herein include amine oxides
of the formula R
1R
2R
3NO, wherein each of R
1, R
2 and R
3 is independently a saturated, substituted or unsubstituted, linear or branched hydrocarbon
chain having from 1 to 30 carbon atoms. Preferred amine oxide surfactants to be used
according to the present invention are amine oxides of the formula R
1R
2R
3NO, wherein R
1 is an hydrocarbon chain having from 1 to 30 carbon atoms, preferably from 6 to 20,
more preferably from 8 to 16, most preferably from 8 to 12, and wherein R
2 and R
3 are independently substituted or unsubstituted, linear or branched hydrocarbon chains
having from 1 to 4 carbon atoms, preferably from 1 to 3 carbon atoms, and more preferably
are methyl groups. R
1 may be a saturated, substituted or unsubstituted, linear or branched hydrocarbon
chain. Suitable amine oxides for use herein are for instance natural blend C
8-C
10 amine oxides as well as C
12-C
16 amine oxides commercially available from Hoechst. Amine oxides are preferred herein
as they deliver effective cleaning performance and further participate to the disinfecting
properties of the disinfecting wipes herein.
[0048] Suitable zwitterionic surfactants to be used herein contain both cationic and anionic
hydrophilic groups on the same molecule at a relatively wide range of pH's. The typical
cationic group is a quaternary ammonium group, although other positively charged groups
like phosphonium, imidazolinium and sulfonium groups can be used. The typical anionic
hydrophilic groups are carboxylates and sulfonates, although other groups such as
sulfates, phosphonates, and the like can be used. A generic formula for some zwitterionic
surfactants to be used herein is
R
1-N+(R
2)(R
3)R
4X-
wherein R
1 is a hydrophobic group; R
2 and R
3 are each C
1-C
4 alkyl, hydroxy alkyl or other substituted alkyl group which can also be joined to
form ring structures with the N; R
4 is a moiety joining the cationic nitrogen atom to the hydrophilic group and is typically
an alkylene, hydroxy alkylene, or polyalkoxy group containing from 1 to 10 carbon
atoms; and X is the hydrophilic group which is preferably a carboxylate or sulfonate
group. Preferred hydrophobic groups R
1 are alkyl groups containing from 1 to 24, preferably less than 18, more preferably
less than 16 carbon atoms. The hydrophobic group can contain unsaturation and/or substituents
and/or linking groups such as aryl groups, amido groups, ester groups and the like.
In general, the simple alkyl groups are preferred for cost and stability reasons.
[0049] Highly preferred zwitterionic surfactants include betaine and sulphobetaine surfactants,
derivatives thereof or mixtures thereof. Said betaine or sulphobetaine surfactants
are preferred herein as they help disinfecting by increasing the permeability of the
bacterial cell wall, thus allowing other active ingredients to enter the cell.
[0050] Furthermore, due to the mild action profile of said betaine or sulphobetaine surfactants,
they are particularly suitable for the cleaning of delicate surfaces, e.g., hard surfaces
in contact with food and/or babies. Betaine and sulphobetaine surfactants are also
extremely mild to the skin and/or surfaces to be treated.
[0051] Suitable betaine and sulphobetaine surfactants to be used herein are the betaine/sulphobetaine
and betaine-like detergents wherein the molecule contains both basic and acidic groups
which form an inner salt giving the molecule both cationic and anionic hydrophilic
groups over a broad range of pH values. Some common examples of these detergents are
described in U.S. Pat. Nos. 2,082,275, 2,702,279 and 2,255,082, incorporated herein
by reference. Preferred betaine and sulphobetaine surfactants herein are according
to the formula

wherein R
1 is a hydrocarbon chain containing from 1 to 24 carbon atoms, preferably from 8 to
18, more preferably from 12 to 14, wherein R
2 and R
3 are hydrocarbon chains containing from 1 to 3 carbon atoms, preferably 1 carbon atom,
wherein n is an integer from 1 to 10, preferably from 1 to 6, more preferably is 1,
Y is selected from the group consisting of carboxyl and sulfonyl radicals and wherein
the sum of R
1, R
2 and R
3 hydrocarbon chains is from 14 to 24 carbon atoms, or mixtures thereof.
[0052] Examples of particularly suitable betaine surfactants include C
12-C
18 alkyl dimethyl betaine such as coconut-betaine and C
10-C
16 alkyl dimethyl betaine such as laurylbetaine. Coconutbetaine is commercially available
from Seppic under the trade name of Amonyl 265". Laurylbetaine is commercially available
from Albright & Wilson under the trade name Empigen BB/L".
[0053] Other specific zwitterionic surfactants have the generic formulas:
R
1-C(O)-N(R
2)-(C(R
3)
2)
n-N(R
2)
2(+)-(C(R
3)
2)
n-SO
3(-);
or
R
1-C(O)-N(R
2)-(C(R
3)
2)
n-N(R
2)
2(+)-(C(R
3)
2)
n-COO
(-)
wherein each R
1 is a hydrocarbon, e.g. an alkyl group containing from 8 up to 20, preferably up to
18, more preferably up to 16 carbon atoms, each R
2 is either a hydrogen (when attached to the amido nitrogen), short chain alkyl or
substituted alkyl containing from 1 to 4 carbon atoms, preferably groups selected
from the group consisting of methyl, ethyl, propyl, hydroxy substituted ethyl or propyl
and mixtures thereof, preferably methyl, each R
3 is selected from the group consisting of hydrogen and hydroxy groups and each n is
a number from 1 to 4, preferably from 2 to 3, more preferably 3, with no more than
one hydroxy group in any (C(R
3)
2) moiety. The R
1 groups can be branched and/or unsaturated. The R
2 groups can also be connected to form ring structures. A surfactant of this type is
a C
10-C
14 fatty acylamidopropylene-(hydroxypropylene)sulfobetaine that is available from the
Sherex Company under the trade name "Varion CAS sulfobetaine"".
[0054] Suitable nonionic surfactants to be used herein are fatty alcohol ethoxylates and/or
propoxylates which are commercially available with a variety of fatty alcohol chain
lengths and a variety of ethoxylation degrees. Indeed, the HLB values of such alkoxylated
nonionic surfactants depend essentially on the chain length of the fatty alcohol,
the nature of the alkoxylation and the degree of alkoxylation. Surfactant catalogues
are available which list a number of surfactants, including nonionics, together with
their respective HLB values.
[0055] Particularly suitable for use herein as nonionic surfactants are the hydrophobic
nonionic surfactants having an HLB (hydrophilic-lipophilic balance) below 16 and more
preferably below 15. Those hydrophobic nonionic surfactants have been found to provide
good grease cutting properties.
[0056] Preferred nonionic surfactants for use herein are nonionic surfactants according
to the formula RO-(C
2H
4O)n(C
3H
6O)
mH, wherein R is a C
6 to C
22 alkyl chain or a C
6 to C
28 alkyl benzene chain, and wherein n+m is from 0 to 20 and n is from 0 to 15 and m
is from 0 to 20, preferably n+m is from 1 to 15 and, n and m are from 0.5 to 15, more
preferably n+m is from 1 to 10 and, n and m are from 0 to 10. The preferred R chains
for use herein are the C
8 to C
22 alkyl chains. Accordingly, suitable hydrophobic nonionic surfactants for use herein
are Dobanol R 91-2.5 (HLB= 8.1; R is a mixture of C
9 and C
11 alkyl chains, n is 2.5 and m is 0), or Lutensol R T03 (HLB=8; R is a C13 alkyl chains,
n is 3 and m is 0), or Lutensol R A03 (HLB=8; R is a mixture of C
13 and C
15 alkyl chains, n is 3 and m is 0), or Tergitol R 25L3 (HLB= 7.7; R is in the range
of C
12 to C
15 alkyl chain length, n is 3 and m is 0), or Dobanol R 23-3 (HLB=8.1; R is a mixture
of C
12 and C
13 alkyl chains, n is 3 and m is 0), or Dobanol R 23-2 (HLB=6.2; R is a mixture of C
12 and C
13 alkyl chains, n is 2 and m is 0), or Dobanol R 45-7 (HLB=11.6; R is a mixture of
C
14 and C
15 alkyl chains, n is 7 and m is 0) Dobanol R 23-6.5 (HLB=11.9; R is a mixture of C
12 and C
13 alkyl chains, n is 6.5 and m is 0), or Dobanol R 25-7 (HLB=12; R is a mixture of
C
12 and C
15 alkyl chains, n is 7 and m is 0), or Dobanol R 91-5 (HLB=11.6; R is a mixture of
C
9 and C
11 alkyl chains, n is 5 and m is 0), or Dobanol R 91-6 (HLB=12.5; R is a mixture of
C
9 and C
11 alkyl chains, n is 6 and m is 0), or Dobanol R 91-8 (HLB=13.7; R is a mixture of
C
9 and C
11 alkyl chains, n is 8 and m is 0), Dobanol R 91-10 (HLB=14.2; R is a mixture of C
9 to C
11 alkyl chains, n is 10 and m is 0), or mixtures thereof. Preferred herein are Dobanol
R 91-2.5, or Lutensol R TO3, or Lutensol R AO3, or Tergitol R 25L3, or Dobanol R 23-3,
or Dobanol R 23-2, or Dobanol R 23-10, or mixtures thereof. DobanolR surfactants are
commercially available from SHELL. LutensolR surfactants are commercially available
from BASF and the Tergitol R surfactants are commercially available from UNION CARBIDE.
[0057] Suitable anionic surfactants to be used herein include water soluble salts or acids
of the formula ROSO
3M wherein R is preferably a C
6-C
24 hydrocarbyl, preferably an alkyl or hydroxyalkyl having a C
8-C
20 alkyl component, more preferably a C
8-C
18 alkyl or hydroxyalkyl, and M is H or a cation, e.g., an alkali metal cation (e.g.,
sodium, potassium, lithium), or ammonium or substituted ammonium (e.g., methyl-, dimethyl-,
and trimethyl ammonium cations and quaternary ammonium cations, such as tetramethyl-ammonium
and dimethyl piperdinium cations and quaternary ammonium cations derived from alkylamines
such as ethylamine, diethylamine, triethylamine, and mixtures thereof, and the like).
[0058] Other suitable anionic surfactants to be used herein include alkyl-diphenylether-sulphonates
and alkyl-carboxylates. Other anionic surfactants can include salts (including, for
example, sodium, potassium, ammonium, and substituted ammonium salts such as mono-,
di- and triethanolamine salts) of soap, C
9-C
20 linear alkylbenzenesulfonates, C
8-C
22 primary or secondary alkanesulfonates, C
8-C
24 olefinsulfonates, sulfonated polycarboxylic acids prepared by sulfonation of the
pyrolyzed product of alkaline earth metal citrates, e.g., as described in British
patent specification No. 1,082,179, C
8-C
24 alkylpolyglycolethersulfates (containing up to 10 moles of ethylene oxide); alkyl
ester sulfonates such as C
14-16 methyl ester sulfonates; acyl glycerol sulfonates, fatty oleyl glycerol sulfates,
alkyl phenol ethylene oxide ether sulfates, paraffin sulfonates, alkyl phosphates,
isethionates such as the acyl isethionates, N-acyl taurates, alkyl succinamates and
sulfosuccinates, monoesters of sulfosuccinate (especially saturated and unsaturated
C
12-C
18 monoesters) diesters of sulfosuccinate (especially saturated and unsaturated C
6-C
14 diesters), acyl sarcosinates, sulfates of alkylpolysaccharides such as the sulfates
of alkylpolyglucoside (the nonionic nonsulfated compounds being described below),
branched primary alkyl sulfates, alkyl polyethoxy carboxylates such as those of the
formula RO(CH
2CH
2O)
kCH
2COO-M+ wherein R is a C
8-C
22 alkyl, k is an integer from 0 to 10, and M is a soluble salt-forming cation. Resin
acids and hydrogenated resin acids are also suitable, such as rosin, hydrogenated
rosin, and resin acids and hydrogenated resin acids present in or derived from tall
oil. Further examples are given in "Surface Active Agents and Detergents" (Vol. I
and II by Schwartz, Perry and Berch). A variety of such surfactants are also generally
disclosed in U.S. Patent 3,929,678, issued December 30, 1975 to Laughlin, et al. at
Column 23, line 58 through Column 29, line 23 (herein incorporated by reference).
[0059] Preferred anionic surfactants for use herein are the alkyl benzene sulfonates, alkyl
sulfates, alkyl alkoxylated sulfates, paraffin sulfonates and mixtures thereof.
[0060] The internal disinfecting polar phase according to the present invention has a pH
of from 1 to 12, preferably from 1.5 to 10, and more preferably from 2 to 9. The pH
can be adjusted by using alkalinizing agents or acidifying agents. Examples of alkalinizing
agents are alkali metal hydroxides, such as potassium and/or sodium hydroxide, or
alkali metal oxides such as sodium and/or potassium oxide. Examples of acidifying
agents are organic or inorganic acids such as citric or sulfuric acid.
[0061] Solvents may be present in the liquid composition according to the present invention.
These solvents will, advantageously, give an enhanced cleaning to the disinfecting
wipes of the present invention. Suitable solvents for incorporation herein include
propylene glycol derivatives such as n-butoxypropanol or n-butoxypropoxypropanol,
water-soluble CARBITOL, solvents or water-soluble CELLOSOLVE, solvents. Water-soluble
CARBITOL, solvents are compounds of the 2-(2-alkoxyethoxy)ethanol class wherein the
alkoxy group is derived from ethyl, propyl or butyl. A preferred water-soluble carbitol
is 2-(2-butoxyethoxy)ethanol also known as butyl carbitol. Water-soluble CELLOSOLVE,
solvents are compounds of the 2-alkoxyethoxyethanol class, with 2-butoxyethoxyethanol
being preferred. Other suitable solvents are benzyl alcohol, methanol, ethanol, isopropyl
alcohol and diols such as 2-ethyl-1,3-hexanediol and 2,2,4-trimethyl-1,3-pentanediol
and mixture thereof. Preferred solvents for use herein are n-butoxypropoxypropanol,
butyl carbitol, and mixtures thereof. A most preferred solvent for use herein is butyl
carbitol.
[0062] The liquid composition may further comprise other optional ingredients including
radical scavengers, chelating agents, thickeners, builders, buffers, stabilizers,
bleach activators, soil suspenders, dye transfer agents, brighteners, anti dusting
agents, enzymes, dispersant, dye transfer inhibitors, pigments, perfumes, and dyes
and the like.
[0063] Suitable radical scavengers for use herein include the well-known substituted mono
and di hydroxy benzenes and derivatives thereof, alkyl- and aryl carboxylates and
mixtures thereof. Preferred radical scavengers for use herein include di-tert-butyl
hydroxy toluene (BHT), p-hydroxy-toluene, hydroquinone (HQ), di-tert-butyl hydroquinone
(DTBHQ), mono-tert-butyl hydroquinone (MTBHQ), tert-butyl-hydroxy anysole, p-hydroxy-anysol,
benzoic acid, 2,5-dihydroxy benzoic acid, 2,5-dihydroxyterephtalic acid, toluic acid,
catechol, t-butyl catechol, 4-allyl-catechol, 4-acetyl catechol, 2-methoxy-phenol,
2-ethoxy-phenol, 2-methoxy-4-(2-propenyl)phenol, 3,4-dihydroxy benzaldehyde, 2,3-dihydroxy
benzaldehyde, benzylamine, 1,1,3-tris(2-methyl-4-hydroxy-5-t-butylphenyl) butane,
tert-butyl-hydroxy-anyline, p-hydroxy anyline as well as n-propyl-gallate. Highly
preferred for use herein is di-tert-butyl hydroxy toluene, which is for example commercially
available from SHELL under the trade name IONOL CP".
[0064] Typically, the radical scavenger, or a mixture thereof, is present in the liquid
composition up to a level of 5% by weight, preferably from 0.001 % to 3% by weight,
and more preferably from 0.001% to 1.5%.
[0065] Suitable chelating agents to be used herein may be any chelating agent known to those
skilled in the art such as the ones selected from the group consisting of phosphonate
chelating agents, amino carboxylate chelating agents or other carboxylate chelating
agents, or polyfunctionally-substituted aromatic chelating agents and mixtures thereof.
[0066] Such phosphonate chelating agents may include etidronic acid (1-hydroxyethylidene-bisphosphonic
acid or HEDP) as well as amino phosphonate compounds, including amino alkylene poly
(alkylene phosphonate), alkali metal ethane 1-hydroxy diphosphonates, nitrilo trimethylene
phosphonates, ethylene diamine tetra methylene phosphonates, and diethylene triamine
penta methylene phosphonates. The phosphonate compounds may be present either in their
acid form or as salts of different cations on some or all of their acid functionalities.
Preferred phosphonate chelating agents to be used herein are diethylene triamine penta
methylene phosphonates. Such phosphonate chelating agents are commercially available
from Monsanto under the trade name DEQUEST.
[0067] Polyfunctionally-substituted aromatic chelating agents may also be useful herein.
See U.S. Patent 3,812,044, issued May 21, 1974, to Connor et al. Preferred compounds
of this type in acid form are dihydroxydisulfobenzenes such as 1,2-dihydroxy -3,5-disulfobenzene.
[0068] A preferred biodegradable chelating agent for use herein is ethylene diamine N,N'-
disuccinic acid, or alkali metal, or alkaline earth, ammonium or substitutes ammonium
salts thereof or mixtures thereof. Ethylenediamine N,N'- disuccinic acids, especially
the (S,S) isomer have been extensively described in US patent 4, 704, 233, November
3, 1987 to Hartman and Perkins. Ethylenediamine N,N'-disuccinic acid is, for instance,
commercially available under the tradename ssEDDS, from Palmer Research Laboratories.
[0069] Suitable amino carboxylate chelating agents useful herein include ethylene diamine
tetra acetate, diethylene triamine pentaacetate, diethylene triamine pentaacetate
(DTPA), N-hydroxyethylethylenediamine triacetate, nitrilotri-acetate, ethylenediamine
tetraproprionate, triethylenetetraaminehexa-acetate, ethanoldiglycine, propylene diamine
tetracetic acid (PDTA) and methyl glycine di-acetic acid (MGDA), both in their acid
form, or in their alkali metal, ammonium, and substituted ammonium salt forms. Particularly
suitable to be used herein are diethylene triamine penta acetic acid (DTPA), propylene
diamine tetracetic acid (PDTA) which is, for instance, commercially available from
BASF under the trade name Trilon FS, and methyl glycine di-acetic acid (MGDA).
[0070] Further carboxylate chelating agents to be used herein includes malonic acid, salicylic
acid, glycine, aspartic acid, glutamic acid, dipicolinic acid and derivatives thereof,
or mixtures thereof.
[0071] Typically, the chelating agent, or a mixture thereof, is present in the liquid composition
at a level of from 0.001 % to 5% by weight, preferably from 0.001% to 3% by weight
and more preferably from 0.001 % to 1.5%.
[0072] The disinfecting wipes according to the present invention are suitable for disinfecting
various surfaces including animate surfaces (e.g. human skin) as well as inanimate
surfaces including any hard-surfaces.
[0073] Other water-soluble or dispersible materials that can be present in the liquid composition
include thickeners and viscosity modifiers. Suitable thickeners and viscosity modifiers
include polyacrylic and hydrophobically modified polyacrylic resins such as Carbopol
and Pemulen, starches such as corn starch, potato starch, tapioca, gums such as guar
gum, gum arabic, cellulose ethers such as hydroxypropyl cellulose, hydroxyethyl cellulose,
carboxymethyl cellulose, and the like. These thickeners and viscosity modifiers will
typically be included in a concentration in the range of from about 0.05 to about
0.5% of the liquid composition.
[0074] Again, where water is a major constituent of the liquid composition, water-soluble
or dispersible materials that can be present in the internal phase include polycationic
polymers to provide steric stabilization at the polar phase-lipid phase interface
and nonionic polymers that also stabilize the emulsion. Suitable polycationic polymers
include Reten 201, Kymene® 557H and Acco 711. Suitable nonionic polymers include polyethylene
glycols (PEG) such as Carbowax and poly(propylene glycol) butyl ether. These polycationic
and nonionic polymers will typically be included in a concentration in the range of
from about 0.05 to about 1.0% of the liquid composition.
[0075] According to the present invention, for wet wipe application designed specifically
for use on the human skin such as baby wipes, the composition may be aqueous, alcohol
based or an emulsion, either a water-in-oil or an oil-in-water or a multiple emulsion,
preferably the emulsion is a oil-in-water emulsion. Typically, the composition will
comprise from 2% to 50% by weight of said composition of actives and from 50% to 98%
water, preferably de-ionised or distilled. Of the active component, preferably 2%
to 20% are present in the oil phase and the remainder are present in the aqueous phase.
[0076] According to the present invention the wet wipes are provided with an emulsion composition
comprising a oil phase in the range of 1% to 20%, preferably 2% to 10%, by weight
of the composition. Advantageously, the oil based phase is derived from natural resources
such as from vegetable or animal oils or may be synthetic or any mixtures thereof.
Suitable vegetable and animal oils for use herein include waxes such as beeswax, lanolin,
candelilla, and oils such as glycerine esters and glycerine ethers, fatty acid alcohols,
fatty acid esters and fatty acid ethers such as caprylic and capric triglycerides
and octylpalmitate. Suitable mineral oils include petroleum based oils such as paraffin
and petroleum jelly. Synthetic oils for use herein include ethylenic polymers for
example polyethylene wax or silicone based oils. Suitable silicon oils include polydimethylsiloxanes,
volatile cyclomethicones, dimethiconols, siloxysilicates and amino- and phenyl derivatives
of siloxanes and mixtures thereof. Examples include dimethicone (Dow Corning 200 Fluids),
cyclomethicone and dimethiconol (Dow Corning 1401 Fluid), cetyl dimethicone (Dow Corning
2502 Fluid), dimethicone and trimethylsiloxysilicate (Dow Corning 593 Fluid), cyclomethicone
(Dow Corning 244, 245, 344 or 345 Fluid), phenyl trimethicone (Dow Corning 556 Fluid),
or combinations thereof.
[0077] The oil-in-water emulsions typically require emulsifying agents. The emulsifying
agents which may be used in the present invention are preferably capable of primary
emulsification of oil-in-water emulsions. The emulsifying agent is present in the
range of 0.02% to 5.0%, preferably 0.02% to 3.0%, by weight of the composition.
[0078] In a preferred embodiment the emulsifying agent is a polymeric type of emulsifying
agent such as a copolymer of C10-C30 alkyl acrylates and one or more monomers of acrylic
acid, methylacrylic acid or one of their simple esters cross linked with an allyl
ether of sucrose or an allyl ether of pentaerythritol. The emulsifying agents which
are thus useful in the present invention include Ceteareth-12, Ceteareth-20 or Pemulen
TR1 and TR2 which are available from B.F. Goodrich company of the USA. However, other
known emulsifying agents such as ethoxylated fatty alcohols, glycerine esters of fatty
acids, soaps, sugar derived agents are also suitable for use herein. Other useful
emulsifying agents include those disclosed in detail in EP-A-328 355.
[0079] According to the present invention the composition may comprise a stability agent
or preservative. Stability agents suitable for use herein include phenoxyethanol preferably
present in the range of from 0.1 to 1.0%, sodium benzoate, potassium sorbate, methylparaben,
propylparaben, ethylparaben, butylparaben, sodium benzoate, potassium sorbate, benzalkonium
chloride, and disodium salt ethylenediamine tetraacetic acid (hereinafter referred
to as EDTA) or other EDTA salts (sequestrenes). Sequestrene is a series of complexing
agents and metal complexes general of ethylenediaminetetraacetic acid and salts. The
total quantity of stability agents should be in the range of 0.1% to 4.0% by weight
of the composition.
[0080] The composition of the present invention may further comprise from 0.02% to 5.0%
by weight of said composition of an emollient or moisturiser. Preferably the emollient
is water soluble and includes polyhydric alcohols, such as propylene glycol, glycerin,
and also water soluble lanolin derivatives.
[0081] In preparing wet wipe products according to the present invention, the composition
is applied to at least one surface of the substrate material. The composition can
be applied at any time during the manufacture of the wet wipe. Preferably the composition
can be applied to the substrate after the substrate has been dried. Any variety of
application methods that evenly distribute lubricious materials having a molten or
liquid consistency can be used. Suitable methods include spraying, printing, (e.g.
flexographic printing), coating (e.g. gravure coating or flood coating) extrusion
whereby the composition is forced through tubes in contact with the substrate whilst
the substrate passes across the tube or combinations of these application techniques.
For example spraying the composition on a rotating surface such as calender roll that
then transfers the composition to the surface of the substrate. The composition can
be applied either to one surface of the substrate or both surfaces, preferably both
surfaces. The preferred application method is extrusion coating.
[0082] The composition can also be applied uniformly or non uniformly to the surfaces of
the substrate. By non uniform it is meant that for example the amount, pattern of
distribution of the composition can vary over the surface of the substrate. For example
some of the surface of the substrate can have greater or lesser amounts of composition,
including portions of the surface that do not have any composition on it. Preferably
however the composition is uniformly applied to the surfaces of the wipes. The composition
is typically applied in an amount of from about 0.5 g to 10 g per gram of substrate,
preferably from 1.0 g to 5 g per gram of substrate, most preferably from 2 g to 4
g per gram of dry substrate.
[0083] Preferably, the composition can be applied to the substrate at any point after it
has been dried. For example the composition can be applied to the substrate prior
to calendering or after calendering and prior to being wound up onto a parent roll.
Typically, the application will be carried out on a substrate unwound from a roll
having a width equal to a substantial number of wipes it is intended to produce. The
substrate with the composition applied thereto is then subsequently perforated utilizing
standard techniques such as in order to produce the desired perforation line.
EXAMPLE I
A) Carrier Preparation
[0084] The carrier is a air laid nonwoven substrate comprising 70% pulp, 15% PET and 15%
latex. The substrate has a basis weight of 73g/m
2.
B) Liquid composition Preparation
[0085] A liquid composition is prepared from the ingredients shown in Table I.
Table I
Ingredients: |
Percentage |
Distilled Water |
87 |
Salicylic acid |
0.03 |
Hydrogen Peroxide |
1.0 |
Ethanol |
9.4 |
C-12 Amine Oxide |
0.4 |
Geraniol |
0.04 |
Thymol |
0.025 |
Citric acid |
0.07 |
Glycol butyl ether |
1.4 |
|
|
[0086] To formulate the composition all the components are mixed together and then heated
to 140°F (45.8°C).
C) Applying the liquid composition to the Carrier
[0087] The liquid composition prepared in step B is applied to the carrier by spraying.
3.25g of lotion per gram of substrate material is applied to the carrier.
[0088] The coated carrier is then perforated, folded and stacked. The stack is then sealed
to yield finished product wipe.
Examples |
Sample |
REF |
REF |
9 |
4 |
1 |
3 |
Bonded area length (mm) |
0.8 |
1.0 |
0.8 |
0.8 |
0.8 |
0.8 |
Primary slit length (mm) |
4 |
3 |
4 |
6.4 |
3.9 |
6.5 |
Secondary slit length (mm) |
- |
- |
1.3 |
1.5 |
1.4 |
1.3 |
No. bonded areas |
1 |
1 |
5 |
5 |
2 |
4 |
No. primary slits |
1 |
1 |
1 |
1 |
1 |
1 |
No. secondary slits |
- |
- |
4 |
4 |
1 |
3 |
Ratio of total slit length |
5 |
3 |
9.2:4 |
3.1 |
3.3 |
3.25 |
Tensile strength (N/inch) |
1.8 |
2.5 |
2.9 |
2.3 |
1.6 |
1.65 |
No. of patterns |
1 |
1 |
1 |
1 |
1 |
1 |
No. of repeat patterns per perforation line |
35 |
42 |
13 |
10 |
25 |
12 |