CN1098059C - Absorbent articles having fluid contact angle gradients - Google Patents

Abstract

The present invention relates to a disposable absorbent article (1) comprising a liquid pervious top sheet (2), an absorbent core (4), and a back sheet (3). Said back sheet comprises a fluid permeable polymeric film having uni-directional fluid transfer towards the core, and said core comprising a fluid storage layer, wherein said absorbent article exhibits a fluid contact angle gradient across said storage layer and said back sheet.

Description

Absorbent device with fluid contact angle gradients

Invention field

The present invention relates to absorbent device, relate in particular to sanitary towel with the breathable backsheet that reduces the wearer medicated clothing probability of getting wet.

Background technology

Consumers in general wish in the absorbent device field especially can develop aspect the menstruation protective pad barrier propterty good, dress extremely comfortable product.

A very ideal measure that improves the absorbent device comfortableness is to adopt so-called " breathable backsheet ".Breathable backsheet can comprise a kind of as United States Patent (USP) 4,591, the porous formed film with directed fluid conveying function described in 523.This porous breathable egative film is porous steam and air normally, allows to carry out gas exchange with surrounding, thereby can make the segment fluid flow evaporation that is stored in the absorbent article core, and strengthened the circulation of air in the absorbent device.Because it has reduced many wearers in use, particularly between in use under the very long situation, so the stickiness feeling of being experienced is advantageous particularly.

But the major defect that adopts breathable backsheet in absorbent device is to have increased the probability of leaking, and is referred to as drenched wearer's medicated clothing usually.Only allow to transmit gaseous material though say this class breathable backsheet in principle, and only transmit fluid to a direction, but still may take place as physical action processes such as extruding, diffusion and capillarities, fluid can be sent on wearer's medicated clothing by egative film in opposite direction as a result.Specifically, having under the long situation of a large amount of Excretas or service time, if use this product, then said process can be more outstanding in the physical action process.In fact, though breathable backsheet has obtained fabulous improvement aspect comfort, they are aspect protection, and particularly the result aspect the protection under stress condition does not reach the degree of making us accepting.

Therefore in this area, it has been recognized that in the absorbent device owing to the problem that has adopted breathable backsheet to get wearer's medicated clothing wet.Some trials of head it off mainly are as United States Patent (USP) 4,341, the such multilamellar egative film that adopts described in 216.Similarly, also disclosed the breathable absorbent articles that comprises breathable backsheet in No. 94203230, undocumented european patent application, above-mentioned breathable backsheet is made of in the disjunct each other air-permeable layer in whole core zone two-layer at least.Also disclosed a kind of breathable backsheet that is used for disposable absorbent article in No. 94203228, undocumented european patent application, this egative film comprises skin and internal layer that comprises the fluidic porous formed film of orientable transmission of a gas-pervious hydrophobic polymer fiber shape fabric.

On the other hand, the method for other head it off that is proposed is the thickness that increases absorbent device, and this measure is normally by increasing the thickness of core, to guarantee to reach desired protection level.

But above-mentioned solution neither one can be entirely satisfactory.Especially for slim product, thickness is considered to influence the key factor of product comfort.Therefore, in the method for the comfortableness that improves absorbent product, exist contradiction two aspect, this makes slim ventilative product can not reach ideal degree of protection.

So a kind of absorbent device need be provided, it can improve the comfortableness of articles for use by adopting breathable backsheet, under the prerequisite that keeps desired protection level, reduces the thickness of articles for use simultaneously.

Have found that in slim sanitary towel and can adopt breathable backsheet, carry out the low-surface-energy processing by adopting as the low-surface-energy material of siloxanes and chlorofluorocarbon and so on or to material, make to produce the hydrophobicity gradient between egative film and the chipware, not only have high protective capacities but also dress comfortable slim sanitary towel thereby provide.It is believed that and in this mode, stoped as diffusion and capillary physical action process, even and think to eliminate fully also and can reduce drenched phenomenon significantly.

Another advantage of the present invention is that so this layer no longer needs all to synthesize, at least a portion can be a natural material owing to allow saturating liquid egative film to apply with hydrophobic material.Because this product has more natural sense of touch, so the advantage that makes consumers in general attract attention is provided.

The application of surface energy gradient has been discussed in undocumented Application No. 08/,442 935.It has disclosed the fluid with surface energy gradient and has transmitted fibre web such as top flat.This fibre web impels fluid to transmit to a direction, and stops fluid to transmit round about.This fibre web comprises first surface and the second surface that separates each other with mid portion.The surface energy of fibre web first surface is lower than the surface energy of mid portion, thereby forms the surface energy gradient.Suitable low-surface-energy material comprises siloxanes, fluoropolymer and paraffin.This fibre web especially is suitable as the top flat of absorbent device, so that fluid is sent to the moisture-absorbent member from the surface that contacts with wearer.

Summary of the invention

A first aspect of the present invention relates to the disposable absorbent article that comprises a saturating liquid top flat, an absorbent article core and an egative film.Absorbent article core is positioned at the centre of top flat and egative film.Above-mentioned egative film comprise a kind of with fluid towards the chipware folk prescription to the saturating liquid thin polymer film that transmits, chipware comprises a fluid storage layer, egative film comprises a skin.Chipware and egative film respectively comprise one deck at least, and wherein each layer all has one towards the surface of wearer with towards the surface of medicated clothing, and all there is a fluid contact angle on each surface of these layers.This absorbent device than lower part outer fieldly extending towards (comprising) from (comprising) fluid storage layer towards the medicated clothing face towards medicated clothing.The invention is characterized in than in the lower part at least one deck towards the fluid contact angle on the surface of wearer adjacent fluid contact angle towards the medicated clothing surface greater than adjacent layer.

A second aspect of the present invention relate to than in the lower part at least one deck towards the fluid contact angle on the surface of medicated clothing greater than situation towards the fluid contact angle on wearer's surface with one deck.

Another aspect of the present invention relates to the production method of above-mentioned absorbent device, and this method is included in than the step of using low-surface-energy material in the lower part at least on the one layer surface.

Another aspect of the present invention relates to the production method of above-mentioned absorbent device, and this method comprises to the step that adds low-surface-energy material than the one deck in the lower part.

Description of drawings

Fig. 1 has made biopsy cavity marker devices to show its structure for the plan view from above of first embodiment of absorbent device of the present invention among the figure;

Fig. 2 is the amplification cross-sectional view of the egative film of the present invention that dissects along 1-1 line among Fig. 1;

Fig. 3 is the cross section enlarged drawing of the last drop of liquid in surface, and angle A represents this drop and this surperficial contact angle among the figure;

Fig. 4 is the cross section enlarged drawing in the lip-deep drop of liquid with two kinds of different surfaces energy, because this surface has two kinds of different surface energies, so this drop has two different contact angle A (a) and A (b).

The specific embodiment

The present invention relates to use disposable absorbent articles such as product and scanties lining as sanitary towel 1, bady's diaper, incontinence patient.Usually, this series products comprises a saturating liquid top flat 2, an egative film 3 and is in absorbent article core 4 between above-mentioned top flat 2 and the egative film 3.Top flat 2, egative film 3 and chipware 4 all have a surface and the surface towards medicated clothing towards wearer.Being connected with each other at periphery 5 places of above-mentioned absorbent device of top flat towards the surface of medicated clothing and the surface towards wearer of egative film.In a preferred embodiment of the invention, this absorbent device has flap, side to surround part or side flap.

Absorbent article core

According to the present invention, absorbent article core comprises first and second portion, and above-mentioned first comprises following parts: (a) optional main fluid Distribution Layer preferably has an optional secondary fluid Distribution Layer simultaneously; (b) fluid storage layer; And above-mentioned second portion comprises: (c) optional fiber (" bottoming ") layer below storing layer; (d) other optional feature.

According to the present invention, the thickness of absorbent article core depends on the final use of its expectation.In a preferred embodiment of the invention, above-mentioned absorbent device is sanitary towel or scanties lining, and the thickness of chipware can be from 15 millimeters to 1 millimeter, preferably from 10 millimeters to 1 millimeter, preferably from 7 millimeters to 1 millimeter.

A. master/secondary fluid Distribution Layer

An optional feature of the first of absorbent article core of the present invention is main fluid Distribution Layer and secondary fluid Distribution Layer.Main Distribution Layer and is communicated with the top flat fluid generally below top flat.Top flat is sent to this main Distribution Layer with the fluid of collecting, and it is assigned to and stores in the layer the most at last.FLUID TRANSPORTATION by main Distribution Layer is not only carried out along the thickness direction of this absorbent device, but also carries out along length and width.The secondary fluid Distribution Layer also is an optional feature, but preferred components, it generally is positioned at below the main Distribution Layer, and is communicated with main Distribution Layer fluid.The purpose that secondary Distribution Layer is set is the fluid for the easier autonomous Distribution Layer of collecting, and it promptly is sent to following storage layer.This helps to make full use of the ability of the store fluid of following storage layer.This fluid distribution layer generally can be made by any material that is generally used for this Distribution Layer.

B. fluid storage layer

Be communicated with main fluid Distribution Layer or secondary fluid Distribution Layer fluid, and to be usually located at below main fluid Distribution Layer or the secondary fluid Distribution Layer be fluid storage layer 6.The fluid storage layer can comprise any hygroscopic material commonly used or the combination of several hygroscopic materials.This storage layer preferably comprises bonded with suitable carriers, as to be referred to as " hydrogel ", " superabsorbent material ", " hydrocolloid " usually sucting wet gel material.

Above-mentioned sucting wet gel material can absorb a large amount of aqueous body fluid, and also can keep this absorbed fluid at suitable pressures.Above-mentioned sucting wet gel material can be dispersed in the suitable carriers equably or anisotropically.If this suitable carriers is hygroscopic, also can use this suitable carriers separately.

Suitable sucting wet gel material used in the present invention the most generally comprises a kind of water-fast basically, weak crosslinked, neutral polymer gel material of part.This material runs into water and forms hydrogel.This polymeric material can prepare with polymerisable, undersaturated acidiferous monomer well known in the art.

Suitable carriers comprises in the moisture-absorbent member material commonly used, as natural, modification or synthetic fibers, especially modification or unmodified cellulose fiber, is fluffing shape and/or tissue paper shape.Suitable carriers and above-mentioned sucting wet gel material can be used together, also can be used alone carrier certainly or several carriers are mixed use.Most preferably tissue paper or tissue paper lamination in sanitary towel and scanties lining structure.

An embodiment according to the prepared moisture-absorbent member of the present invention comprises the folding double-deck tissue paper lamination that forms of tissue paper itself.For example can these layers be combined togather by bonding or mechanical link or hydrogen bridge bonding (hydrogen bridge bonds).Between these layers, can comprise sucting wet gel material or other optional material.

Also can adopt as cellulose fibre through modifications such as hardened cellulose fibres, also can adopt synthetic fibers, these synthetic fibers comprise the fiber of being made by following material, these materials are: cellulose acetate, polyvinyl fluoride, Vingon, acrylic compounds (as Orlon, the polyacrylonitrile silk), polyvinylacetate, insoluble polyvinyl alcohol, polyethylene, polypropylene, polyamide (as nylon), polyester, bicomponent fibre, tricomponent fibre and their mixture etc.Preferred above-mentioned fiber surface is hydrophilic, or is processed into hydrophilic.Storing layer also can comprise as fillers such as perlite, kieselguhr, Vermiculitums, to improve (retention) ability that retains of liquid.

If it is inhomogeneous that sucting wet gel material disperses in carrier, however storing layer can be local uniform, promptly has distribution gradient on a direction or several direction in the scope that stores layer.Non-uniform Distribution can also be related to the carrier lamination that surrounds part or all of sucting wet gel material.

C. Ren Xuan fiber (" bottoming ") layer

An optional component that is included in the absorbent article core of the present invention is an adjacency, and the fibrous layer below storing layer normally.Owing in the process of making absorbent article core, should provide substrate for deposition sucting wet gel material in storing layer at the fibrous layer of lower floor, so this fibrous layer often is called as " bottoming " layer.In fact, when sucting wet gel material is the form of macrostructure such as fibrous, lamellar or bar form, do not need to comprise this fiber " bottoming " layer.Certainly, this " bottoming " layer also has some auxiliary fluid treatment abilities, for example can be along the length direction of liner rapid siphon fluid.

D. other optional component of moisture-absorbent member

Absorbent article core of the present invention also can comprise other optional component that is present in usually in the moisture absorption fibre web.For example, can be configured between interior or each layer of each layer of absorbent article core strengthening scrim nonwoven fabric (reinforcing scrim).This class strengthens scrim nonwoven fabric should have the structure that does not form the interface barrier that hinders FLUID TRANSPORTATION.If adopt the structural entity that forms owing to heat bonding usually, then the moisture-absorbent member of heat bonding does not generally need to strengthen scrim nonwoven fabric.

Can be included in the absorbent article core of the present invention and be preferably near or be odor control agent as another component of the part of main fluid Distribution Layer or secondary fluid Distribution Layer configuration.The optional active carbon (what especially be fit to is zeolite or clay material) that will be coated with or be added with other odor control agent joins in the moisture-absorbent member.These components can be any desirable forms, but normally add in the moisture-absorbent member with the form of discrete particle.

Top flat

Top flat 21 can be single or multiple lift.In a preferred embodiment, pre-sheet comprise provide top flat towards the ground floor 22 on the surface of wearer and be in ground floor and moisture-absorbent member/core between the second layer 23.

Top flat 21 is made as a whole and its each layer all should submissive, soft feel, and wearer's skin is had no stimulation.Top flat also can have elasticity, can stretch on one or two direction.According to the present invention, top flat can be made by any well known materials that can satisfy above-mentioned requirements, for example non woven fibre, thin film or both coalitions.In a preferred embodiment of the invention, in the top flat at least one deck (preferably upper strata) comprise the porous polymer film 22 of liquid.

The most handy liquid that can promote prepares the upper strata from the perforated membrane membrane material that transmits to moisture-absorbent member towards the wearer surface, for example resembles at United States Patent (USP) 3,929 No. 135,4,151, No. 240,4,319, No. 868,4,324, No. 426,4,343, No. 314 and 4,591, describe in detail in No. 523 like that.

Usually, top flat stretches and covers whole moisture-absorbent member, and can extend on preferential side flap, gusset spare or the flap, and forms they part or all.

Egative film

Absorbent device of the present invention comprises that a folk prescription is to transmitting fluidic breathable backsheet 24.The main effect of egative film is to prevent to be absorbed and to be retained in article such as underpants, medicated underpants, pyjamas and the underwear that the Excreta in the moisture-absorbent member is got wet and contacted with absorbent device.In addition, the egative film of absorbent device of the present invention also allows steam and air to transmit by it, therefore can make air in the inside and outside circulation of this egative film.

Term as used in this specification " folk prescription to " is meant to possess basically (if not whole words) at least to the fluidic material of the one-way transmission of chipware direction.Fluidic directivity can be with below the test method 3 in the test method of describing in detail being distinguished.

Egative film of the present invention preferably includes two-layer at least: comprise the ground floor of ventilating porous thin polymer film 25, comprise the second layer of gas-pervious fiber fabric layer 26.Above-mentioned ground floor preferably has similarly relative void volume (relative void volume) with the second layer.General ground floor is near chipware 27, and ensuing those layers of egative film dispose away from chipware usually.This egative film also can comprise extra play.In all situations, be outer from chipware layer farthest, each layer of all of egative film is adjacent to each other basically and be in direct contact with one another.

The porous ground floor of egative film 25 comprises a layer with discrete hole 28, and above-mentioned hole exceeds the horizontal plane towards the medicated clothing face of that layer of chipware, thereby forms some outthrust 29.The terminal of each outthrust has an aperture.Above-mentioned outthrust preferably has the United States Patent (USP) of being similar to 3,929, infundibulate described in 135 or taper shape.The hole that is positioned at this layer plane can be circular or non-circular with the aperture itself that is positioned at the outthrust terminal.Which kind of situation no matter, the cross sectional dimensions of outthrust terminal aperture or area are all less than the cross sectional dimensions or the area in the hole in this layer plane.The aperture area of egative film ground floor is preferably 10% to 35% usually greater than 5% of this thin layer gross area.With the aperture area that in the following test method test method of describing 4 can be determined this layer.

According to the present invention, the ground floor of above-mentioned egative film 25 can be made by any material commonly known in the art, but is preferably made by the polymeric material that can get usually.

The second layer of above-mentioned egative film comprises the gas-pervious fiber fabric layer 26 that is made of as the polymer fiber of non woven cloth in polymer commonly known in the art.This fiber fabric layer quantitatively be preferably 10 to 100 the gram/square metre, be preferably 15 to 30 the gram/square metre.Available any polymeric material, especially polyethylene, polypropylene, polyester, poly-acetate fiber or their combination (in the fiber and interfibrous combination) makes above-mentioned fiber fabric layer, also can adopt the mixture of staple fibre and nonhygroscopic natural fiber or treated natural fiber (as cotton).Preferably through spunbond, combing or the fiber that melts and sprays.Preferred this second layer comprises the spun-bonded fibre matrix of a side by the meltblown fibers covering, perhaps also can select both sides by the meltblown fibers matrix that spins spray (spun blown) fiber-covered.In addition, the second layer of egative film can also comprise the above-mentioned fibrous layer of at least 5% weight, and this fiber is to absorb liquid, thereby can make these fibre swellings and reduce interfibrous gap.

Egative film strides across whole moisture-absorbent member usually, and can extend to preferred side flap, side is replied the part or the wing, constitutes they part or all.

The fluid contact angle

According to a first aspect of the present invention, arbitrary layer than lower part all has towards the wearer surface with towards the medicated clothing surface, and all there is a fluid contact angle on above-mentioned each surface, wherein above-mentioned than in the lower part at least the fluid contact angle that has towards the wearer surface of one deck greater than adjacent the fluid contact angle of adjacent layer towards the medicated clothing surface towards the medicated clothing surface.

According to a second aspect of the present invention, above-mentioned arbitrary layer than lower part all has towards the wearer surface with towards the medicated clothing surface, all there is a fluid contact angle on each surface of above-mentioned each layer, wherein above-mentioned than in the lower part at least the fluid contact angle that has towards the medicated clothing mask of one deck greater than fluid contact angle towards the wearer surface with one deck.

In principle, can there be contact angle gradient between any surface (towards the surface of wearer or towards the surface of medicated clothing) of any layer above-mentioned in than lower part.Therefore, than pass in the lower part with one deck towards wearer and between the adjacently situated surfaces of medicated clothing surface and adjacent layer, can have fluid contact angle gradients towards the surface of medicated clothing or at one deck at least, that is to say, the egative film ground floor towards wearer surface and towards between the medicated clothing surface, the egative film ground floor towards the medicated clothing face and the egative film second layer towards between the wearer surface, the egative film second layer towards the wearer surface with towards having fluid contact angle gradients between the medicated clothing face or between any backsheet layer that is close to.In addition, also can predict also and can will have the above-mentioned several layers of use that combines of specific contact angle relation, thereby can form successive contact angle gradient than lower part.

But, in order to describe the present invention briefly, concentrate to describe below chipware towards medicated clothing face and egative film ground floor between the surface of wearer, exist significantly or the contact angle gradient that increases.

As shown in Figure 3, the drop 110 that is in usually on the surface of solids 112 forms a contact angle A with this surface of solids.The wettability of the surface of solids that is caused by liquid increases, and then contact angle A reduces.The wettability of the surface of solids that is caused by liquid reduces, and then contact angle A increases.Contact angle between liquid-solid can be determined with known technology.As by Arthur W., Adamson (1967) editor's " Surface Physical Chemistry, second edition " ( Physical Chemistry of Surfaces, Second Edition), " U.S. chemical institute magazine " that F.E.Bartell and H.H.Zuidema edit ( J.Am. Chem.Soc), 58,1449 (1936) and J.J.Bikerman " industrial engineering chemistry, analyze version " (Ind.Eng.Chem.Anal.Ed.), describe above-mentioned technology in detail in 13,443 (1941), therefore above-mentioned every piece of document is reference of the present invention.In the field recent publication comprise people such as Cheng " colloid and surface " ( Colloids and Surface) people such as 43:151-167 (1990) and Rotenberg " colloid and interface science magazine " ( Journal of Colloid and Interface Science) 93 (1): 169-183 (1983), these documents also are list of references of the present invention.

Term used herein " hydrophilic " is meant the surface that can be deposited over lip-deep aqueous fluid (as aqueous body fluid) moistening.Hydrophilic and wettability are determined by the contact angle and the surface tension of the involved fluid and the surface of solids usually.Edit by Robert F.Gould, be entitled as Contact Angle by what american chemical association published, among the Wettability and Adhesion (contact angle, wettability and adhesiveness) (publishing in 1964) this is gone through, this literary composition is a list of references of the present invention.When fluid tends to spontaneously pass diffusion into the surface, it is generally acknowledged that this surface is by liquid moistening (hydrophilic).Otherwise in the time of can not passing diffusion into the surface as if aqueous fluid, then this surface is considered to " hydrophobic " with sending out automatically.

Liquid/solid contact angle and surface heterogeneity (as chemistry and physical propertys such as roughness), pollutant, the chemical/physical of the surface of solids is handled or the component of the surface of solids, and the character of liquid and its impurity is relevant.Solid surface energy is also influential to contact angle.If solid surface energy reduces, contact angle increases.When solid surface energy increased, contact angle reduced.

Making liquid separate required energy with the surface of solids (as thin film or fiber) is represented by equation (1):

(1) W＝G(1+cosA)

Wherein: W is with erg/square centimeter, (* 10 ^-3Joule/square metre) metric adhesion work,

G uses dynes per centimeter, (* 10 ^-3Cattle/rice) surface tension of metric liquid,

A is the liquid-solid contact angle, and unit is degree.

For a kind of given liquid, its adhesion work increases (when contact angle was zero, adhesion work reached maximum) with the cosine value of liquid-solid contact angle.

For understanding and quantizing for the energy characteristic on given surface of given liquid, adhesion work is a useful amount.

Table 1 is used for explanation for the solid-liquid contact angle of a kind of particular fluid (as water) and the relation between the bonding merit, and this fluidic surface tension is 75 dynes per centimeter (75 * 10 ^-3Joule/square metre).

Table 1

A (degree) CosA 1+cosA W (erg/square centimeter)

(* 10 ^-3Joule/square metre)

0 1 2 150

30 0.87 1.87 140

60 0.5 1.50 113

90 0 1.00 75

120 -0.5 0.5 38

150 -0.87 0.13 10

180 -1 0 0

As shown in table 1, when the adhesion work of particular surface reduced (this particular surface has less surface energy), fluidic contact angle increased on this surface, so fluid is the pearl (bead up) of projection, and the contact area of occupying is less.Otherwise, also similar variation when the surface energy on given fluidic given surface reduces.So adhesion work is influential to the interfacial fiuid phenomenon on the surface of solids.

The more important thing is, have found that surface energy gradient or discontinuity (discontinuities) with the explanation of fluid contact angle in scope of the present invention are of great use for preventing that fluid from transmitting.Fig. 4 show be positioned at have different surfaces can two zones 113 and the drop 110 on the surface of solids of 115 (representing with different hacures among the figure for purposes of illustration).In situation shown in Figure 4, regional 113 surface energies that have are littler than the surface energy in zone 115, so drop is to wettability 115 reductions than the zone in zone 113.In view of the above, the contact angle A (a) that forms greater than edge of the contact angle A (b) that forms at the edge of drop contact area 113 of this drop 110 in drop contact area 115.Though it should be noted that point " a " and " b " are in the same plane for for the purpose of diagram is clear, the distance " dx " between point " a " and " b " is straight line not necessarily, drop/surperficial contact range available and that this surface configuration has nothing to do is represented.This moment, drop 110 was subjected to unbalanced surface energy effect, and therefore, owing to existing the apparent surface difference (being surface energy gradient or discontinuity) to form external force between district 113 and 115, this external force can be used equation (2) expression:

(2) dF＝G[cosA(a)-cosA(b)]dx

Wherein: dF is the clean power on the fluid droplet,

Dx is the distance between label " a " and " b ",

G such as front define,

A (a) and A (b) are respectively the contact angle that position " a " and " b " locate.

CosA (a) and cosA (b) substitution equation (2) with solving in the equation (1) draw equation (3)

(3) dF＝G[(W(a)/G-1)-(W(b)/G-1)]dx

Equation (3) is reduced to equation (4)

(4) dF＝(W(a)-W(b))dx

Equation (4) clearly reflects the importance of the difference of the surface energy between two surfaces, and the variation of adhesion work difference size is directly proportional with the size of power.

" textile science and technology " ( Textile Science and Technology) (Absorbency) (1985) and " industrial engineering chemistry " " capillarity, theory and practice " of (Ind.Eng.Chem.) writing by A.M.Schwartz in 61,10 (1969) of the 7th volume " absorbability " edited by Portnoy K.Chatterijee ( Capillarity, Tbeory and Practice) in gone through surface energy phenomenon and capillary physical property, above-mentioned document is reference of the present invention.

So will move towards the chipware direction in this case towards surface direction motion after droplet is stressed with higher surface energy.For simple and make figure clear for the purpose of, will clearly limit among Fig. 4 but surface energy gradient or discontinuity between the different constant region of surface energy is depicted as single hop or border.The surface energy gradient also can successive gradient or the form of segmentation (stepwise) gradient exist, the power that is added on any specific droplet (or part drop) is determined by the surface energy on each particular area of droplet contact.

Herein, when with " gradient " but a speech is the variation of describing whole measuring distance inner surface energy or adhesion work when being used to reflect the difference of surface energy or adhesion work." discontinuity " speech refers to a kind of " gradient " or turnover, and wherein to occur in be in zero the distance range substantially in the variation of surface energy.In view of the above, in this description all about the description of " discontinuity " all in the definition of gradient.

" capillaceous " used herein and " capillarity " are meant and can transmit passage, hole, micropore or gap in the fluidic structure according to the capillarity principle, common available Laplace's equation (5) expression:

(5) P＝2G(cosA)/R

Wherein: P is a capillary pressure;

R is internal diameter capillaceous (capillary radius);

The definition of G and A is the same.

As " chemical after-treatment reason fabric " ( Chem.Aftertreat.Text) the III chapter of (1971), the 83-113 page or leaf by " permeability of fabric " of Emery I.Valko work ( Penetration of Fabrics) mentioned in (this literary composition for list of references of the present invention), in the time of A=90 °, cosA is zero, capillary tube does not have pressure.When A＞90 °, cosA is a negative value, and capillary pressure stops fluid to flow into capillary tube.Therefore, for hydrophilic liquid, in order to produce capillarity, capillary wall is answered possess hydrophilic property character.In addition, when increasing (bigger hole/capillary pipe structure) owing to R, capillary pressure reduces, and reasonable for making the P value, R must be enough little.

Almost the same with the existence of surface energy gradient at least importantly surface energy gradient itself is with respect to the orientation of capillary tube or fluid passage itself and the specific direction and the position of position.

Below all water as the example of reference fluids discuss (but and non-limiting).That the physical property of water is determined very much, be easy to obtain, and the common character of the water that obtains wherein is all consistent.Consider the concrete surface tension characteristics of perfect fluid, so can be advantageously used in other fluid (as blood, menstruation and urine) about the notion of the adhesion work of water.

Owing to have the surface energy gradient between chipware and the egative film, make contiguous with egative film that absorbent article core contacts near part surface can be lower, and can be lower towards the part surface that contacts with wearers skin, so egative film can stop drop to move to the egative film that has than low-surface-energy from the chipware with higher surface energy.Owing to make the surface tension imbalance that acts on the solid-liquid contact surface than the contact angle difference between low-surface-energy part and the higher surface energy part, cause droplet flow.Obviously, the formed this surface energy gradient that can produce negative capillary pressure is particularly useful for the porous egative film of absorbent device, for example is applicable to the egative film 2,24 in the absorbent device 1.

According to the description of front, adopt porous egative film can reduce the probability of drenched (wetthrough) with surface energy gradient.If extrude pad outer (as by low surface extrusion) from absorbent article core towards egative film with the fluid that certain power will have been collected, because the backsheet surface that has than low-surface-energy can stop fluid to spill outside the pad by some openings of egative film, so flowing of can preventing that this class from not wishing to occur.

So, because the driving force of surface energy gradient makes that fluid is easier to remain in the absorbent article core between egative film and the chipware.

With regard to surface energy gradient of the present invention, importantly should keep the bound of each gradient firmly in mind and be correlated with each other, that is to say that the boundary zone that limits the egative film of surface energy gradient and chipware needn't be at the not homonymy of hydrophobic/hydrophilic scope.In other words, can have in various degree hydrophobicity or hydrophilic two surfaces in various degree between form gradient, form gradient and needn't be limited between a hydrophobic surface and a water-wetted surface.Except above-mentioned points, at present the upper surface of preferred egative film has than low-surface-energy, promptly is generally hydrophobicly, so that the driving force that is applied on the fluid that flows into from chipware reaches maximum, and makes the probability minimum of moisture penetration to the contact with clothing face of whole egative film.

So in the present invention, above-mentioned surface energy gradient provides a kind of and has seen through the synergy of egative film with the bonded fluid that prevents of egative film one-way transmission fluid behaviour.Fluid on the first surface of egative film be subjected to two different but be complementary driving force, these two power can stop fluid to leave chipware to flow to egative film with towards medicated clothing.Equally, these two power can combine the prevention fluid equally and flow towards egative film, therefore can reduce drenched generation significantly.

According to absorbent device of the present invention, when design porous egative film and chipware, should consider some physical parameters, specifically, should consider suitable dimensions and be the position of the fluidic surface energy gradient of suitable treatments.These factors comprise the mobility of surface energy extent (depending on the material that is adopted), material, biocompatibility, porosity or the capillary size of material, whole thickness and physical dimension, fluid viscosity and surface tension and be with or without other structure on the either sides at these interfaces.

Difference with the fluid contact angle between the two adjacent surfaces of surface energy gradient preferably should be at least 10 °, preferably be at least 20 °, the fluid contact angle that has than the surface of low-surface-energy should be at least 90 °, preferably is at least 100 °, more preferably be at least 110 °, preferably be at least 120 °.

According to the present invention, more hydrophilic by making the surface, can increase the contact angle of this layer.According to the present invention, in order to make egative film as shown in Figure 2, upward the polyethylene tablet is pushed at a rotary drum (drum), on cylinder, make the tablet vacuum form porous formed film, then, if desired, also can be issued to people's such as Thomas United States Patent (USP) 4 according to the nineteen eighty-two JIUYUE on the 28th, 351, No. 784, be issued to people's such as Thomas United States Patent (USP) 4,456 on June 26th, 1984, No. 570, be issued to people's such as Thomas United States Patent (USP) 4 on August 13rd, 1985,535, No. 020 explanation is carried out Corona discharge Treatment to it, and the disclosed content of above-mentioned every piece of patent is reference of the present invention.Then to porous formed film carry out surface treatment towards the wearer surface, make it have relatively low surface energy, preferably make above-mentioned surface cure.A kind of suitable surface treatment is to use the Midland from Dow Corning of, and the Syl-Off 7677 that Michigan buys adds the mixture siloxanes anti-stick coating processing that can buy the Syl-Off7048 cross-linking agent that comes in being respectively 100 parts of ratios to 10 parts by weight.Another kind of suitable surface treatment is the siloxane paint of a kind of UV-curable of coating, this coating comprises can be from General ElectricCompany, Silicone Products Division, Waterford, the mixture of two kinds of siloxanes of the commodity that NY buys UV9300 by name and UV 9380C-D1, the ratio of above-mentioned two kinds of siloxanes is respectively 100 parts and 2.5 parts by weight.Though in some application-specific relevant, proved that some other coating amount also is suitable with the character of egative film and fluidic characteristic etc., but when being used for this class mixture of siloxanes on as shown in Figure 2 the formed film, it is satisfied adopting coating at least 0.25 gram on every per square meter of surface area, preferred 0.5 to 0.8 gram siloxanes.

Other suitable processing material includes, but is not limited to fluorinated material, as fluoropolymer [as the commercially available trade mark of polytetrafluoroethylene (PTFE) TEFLON by name] and chlorine fluoropolymer polymer.Although the biocompatibility of now preferred silicone compositions is suitable in the absorbent device them very much, confirmed that other material that is suitable for providing the surface energy that reduces comprises as Hydrocarbon such as vaseline, latex, paraffin." biocompatibility (biocompatibility) " speech used herein refers to the low material of specific absorption amount that has for various biological substances or biological product material (as glycoprotein, platelet etc.), or in other words is the material of low-affinity.Therefore, under service condition, these materials stop the sedimentary trend of biological substance to be better than other material to a great extent.This character can make above-mentioned material preserve their required surface energy properties in ensuing fluid treatment preferably.Under the situation that does not possess biocompatibility, the deposition of this biomaterial will increase the roughening or the heterogeneity on surface, cause the resistance of fluid motion or drag to increase.Therefore, biocompatibility is corresponding with the fluid flow resistance or the drag of reduction, so can make fluid flow into surface energy gradient and capillary structure quickly.Keeping substantially the same surface energy has also just kept and has been used for subsequently or the initial surface energy difference of long-time fluid deposition.

But biocompatibility is different with the meaning of low-surface-energy.Some material (as polyurethane) has biocompatibility to a certain extent, but it also has higher surface energy.The advantage of presently preferred material such as siloxanes and fluorinated material is not only to have low-surface-energy but also biocompatibility is arranged.

Other method for optimizing that the strip polyethylene film is processed into porous formed film is a jet surface that faces toward film with the high-pressure fluid jet of moisture or analog, and the preferred while keeps vacuum near the opposed surface of this film.Be issued in 2nd JIUYUE in 1986 Curro etc. the people's and made the United States Patent (USP) 4 of common transfer, 609, No. 518, Decembers in 1986 were issued to people's such as Curro United States Patent (USP) 4 on the 16th, 629, No. 643, be issued to people's such as Ouellette United States Patent (USP) 4 on January 20th, 1987,637, No. 819, be issued to people's such as Linman United States Patent (USP) 4 on July 21st, 1987,681, No. 793, JIUYUE in 1987 were issued to people's such as Curro United States Patent (USP) 4,695 on the 22nd, No. 422, be issued to people's such as Curro United States Patent (USP) 4 on October 18th, 1988,778, No. 644, be issued to people's such as Curro United States Patent (USP) 4,839 on June 13rd, 1989, No. 216 and be issued to people's such as Lyons United States Patent (USP) 4 on July 11st, 1989, all described very much these class methods in 846, No. 821 in detail, above-mentioned every piece of patent is list of references of the present invention.If desired, also can carry out Corona discharge Treatment to above-mentioned porous formed film.Can on the first surface of porous formed film, apply then or print the siloxanes adherent layer, above-mentioned adherent layer is solidified.The surface energy on the surface of crossing with siloxane treated is less than the surface energy on the undressed surface of egative film.

In addition, can be in process of production, adding low-surface-energy material in having the layer (as the porous polymer backsheet layer) of low-surface-energy more makes this layer that hydrophobicity is provided in process of production.Low-surface-energy material is coated on the surface of this layer then.The low-surface-energy material that common this layer comprises accounts for 5% of this layer gross weight at least.

Absorbent device of the present invention is combined with method known to a person of ordinary skill in the art by some parts such as top flat, egative film and absorbent article core and constitutes.For example can arrange egative film and/or top flat with the absorbent article core binding or they are connected to each other by even successive adhesive phase, adhesive phase or isolating straight line, helix or spot bonding agent with certain figure stricture of vagina.In addition, also available heat bonding, pressure bonding, ultrasonic bonding, dynamic power machine combine these parts in conjunction with any combination of (dynamic mechanical bonds) or any other suitable manner known to a person of ordinary skill in the art and aforesaid way.

Absorbent device of the present invention can be used as sanitary towel, scanties lining, the incontinence patient that grows up uses pad and bady's diaper.Therefore, except that the parts described in this description, above-mentioned absorbent device also can comprise flexible fastening piece and the like relevant with the behaviour in service of articles for use.The present invention is particularly useful for sanitary towel and scanties lining.

Embodiment

Absorbent device of the present invention can make as follows.

Constitute egative film with following raw material:

A) from Corovin GmbH, the name that Peine, Germany buy be called supatex fabric 28 gram of MD 2005/square metre, it have 14 grams/square metre spunbond layer and 14 grams/square metre meltblown layer.

B) according to United States Patent (USP) 3,929, No. 135 from Tredgar Film Products, the polyethylene shaped film that U.S.A obtains.It is 19% circular port that this film has aperture area, and 0.48 millimeter of embossing thickness (funnel shaped height) is 0.465 millimeter towards the lip-deep aperture of medicated clothing.

By with above-mentioned thin layer (b) with make and spin spray-up and become the non woven fibre towards the medicated clothing surface of absorbent device (a) and combine and can make egative film, wherein the outstanding hole of thin layer towards absorbent device towards wearer's surface orientation.

Except carrying out the special handling at the material of the shaped portion of egative film or the material that contacts with the tight fluid of egative film, each specimen all is with identical condition preparation in every respect.With from Procter ﹠amp; The sanitary belt of the trade mark that Gamble GmbH Schwalbach/Germany buys by name " Always Ultra Normal ", except that seldom with being connected the egative film adnexa of total member, other all routinely manufacture process make above-mentioned specimen.Can remove the existing egative film that constitutes by (both impenetrable liquid, airtight again body) plastic sheetings that can be not saturating like this, and with a kind of alternative breathable backsheet replacement.Remove additional surfaces and handle outside (a liquid/solid surface is handled with silicon coating, make its surface energy lower), the structure of sanitary towel is all identical with all embodiment.

Embodiment 1 (reference)

Aforesaid breathable backsheet is made of the porous membrane with bellmouth (CPT) of unidirectional (direction), the production code number that above-mentioned perforated membrane is produced by U.S. Tredegar is that the low density PE of X-1522 is made, and is located at absorbent article core by tissue paper (tissue) and sucting wet gel material formation and contacts part.Contact surface towards the wearer is made of the nonwoven laminates that the trade mark of producing at the Corovin of Germany GmbH is called MD 2005.This nonwoven laminates by 14 the gram/square metre a spunbond layer and 14 gram/square metre meltblown layers form.It is not carried out additional surfaces handles.

Embodiment 2

Except that by 6 the restraining with quantitatively being about of the absorbent article core tissue paper of Denmark Walkisoft supply towards medicated clothing surface 30 (be in the surface 31 towards the wearer of above-mentioned unidirectional porous membrane and contact part) (MAT'L mark is Metmar Kotka)/square metre the heat cure siloxane treated, structure is identical with structure among the embodiment 1.Above-mentioned siloxanes is produced by U.S. Dow Corning, and the commercial goods is called SYL-OFF 7048Crosslinker/SYL-OFF 7677, anti-stick coating device (release coater) (mixing ratio is 10%: 90%).

Embodiment 3

Except that the production code number of producing by U.S. Tredegar be the above-mentioned unidirectional perforated membrane (CPT) made of the low density PE of X-1522 the surface 31 towards the wearer (be in absorbent article core tissue paper 200 and contact part) with quantitatively be about 3 grams/square metre heat cure siloxanes in addition the processing, structure is identical with structure among the embodiment 1.Above-mentioned siloxanes is produced by U.S. DOW Corning, and the commercial goods is called SYL-OFF 7048 Crosslinker/SYL-OFF 7677, anti-stick coating device (mixing ratio is 10%: 90%).

Embodiment 4

Remove and be used in P﹠amp; Made outside the above-mentioned unidirectional perforated membrane by the low density PE (84%) of Dutch TredegarFilm Products B.V. supply and the mixture of siloxanes (16%) under the requirement of G Pescara Technical Center S.p.A, structure is identical with embodiment 1.The working condition of above-mentioned material and code name are that the working condition of X-1522 material is similar.

Embodiment 5

Except that making outside the above-mentioned unidirectional perforated membrane (CPT) with high density polyethylene (HDPE) (provided by U.S. Tredegar Film Products, the development code name is 15112), structure is identical with embodiment 3.As embodiment 3, (being in the absorbent article core tissue paper and contacting part) of above-mentioned unidirectional perforated membrane (CPT-HDPE) towards wearer surface 31 used quantitatively (basis weight) be about 3 grams/square metre the heat cure siloxanes handled in addition.Above-mentioned siloxanes is produced (commodity are called SYL-OFF 7048Crosslinkers/SYL-OFF 7677, and mixing ratio is 10%: 90%) by U.S. Dow Corning.

Method of testing

Side religious name 1a﹠amp; The drenched test of 1b-(Wet-Through Test)

This drenched test is used to estimate the resistance that breathable backsheet or egative film member transmit Excreta in the body.By changing the composition of test solution simply, this method can directly be measured the liquid-tight situation of porous egative film to Excreta liquid in all bodies, and these will be described in detail in the method below.

The ultimate principle of method

The ultimate principle of this test is the loading condition that has absorbed excremental disposable absorbent article in the body during simulation is used.For this reason, should prepare a kind of product (as sanitary towel), and it is lain on the transparent testing stand of being made by lucite.The placement direction of product is that (upside) exposed on the surface towards the wearer, and makes egative film/contact (bottom side) with testing stand towards the surface of medicated clothing.At liquid conveying system of overhung of sample to be analyzed, this system can provide the desirable test solution (on demand, perhaps be once ejection, perhaps add liquid for series of steps) of any requirement.

One deck moisture absorption filter paper is placed between the outermost surface and transparent testing stand of sample.This moisture absorption filter paper closely contacts with the egative film of sample, so that simulation closely contacts for example sanitary towel or the diaper/incontinence patient articles for use that are attached on the medicated underpants with medicated clothing.Mirror is placed in below near transparent testing stand, and the purpose of this arrangement is to observe any variation of moisture absorption filter paper (simulateding the excremental situation that has color reagent to get wet in the body) continuously.For example, if the porous egative film can not stop liquid to transmit fully, filter paper can be got wet by coloured test solution so, and these variations will be observed from mirror.Except that writing down easily the delivery time, transmit the amount used weight of test solution or the dirty area on the most handy moisture absorption filter paper (simulation medicated clothing) and measure.

As will be discussed later in detail, can test solution be imported in the sample through an induction system of demarcating (as through simple burette) according to desired test mode.In case test solution is carried on the pad, allows 1 minute time chien shih test solution to be absorbed in the sample, so there is not test solution groove (pool) in top flat (towards wearer's surface).

Wait for after 1 minute, this sample placed under the pressure of 70 gram/square centimeters that though can often run into such power in using, people think that still the pressure of above-mentioned pressure reflection is bigger.Kept sample 30 minutes under 70 gram/cm2 pressures, and measured once every 5 minutes, for example measuring has a color contamination area on the active paper.Importantly should measure in a long time, because the flowability or the diffusion process of Excreta (as blood) are more time-consuming in some body.

In order to guarantee correctly to estimate this rigorous test design, the mechanism of understanding drenched accident also is very important.For example, have easier in this accident when sitting down (as suffered pressure will make liquid pass these bigger holes) appears in extrusion process than the breathable backsheet of macropore (＞200 microns), when when this specimen is exerted pressure, this extrusion process will appear rapidly.In addition, Kong Yuexiao (＜200 microns), the diffusion process that simple diffusion process of easy more generation or capillarity cause.These processes are slower than extrusion process.

Method 1a: the simulation (High Gust Simulation) of shoving at a high speed

In this first kind test design, under high capacity (pressurization is gushed out test solution suddenly) simulated conditions, measure the impermeability of porous egative film.In the use this situation be extremely rambunctious (often occur in lie down or sat for a long time after when starting up) because absorbent article core (or member) generally needs the regular hour to work and abundant Excreta and combine with Excreta in the body in the absorber.For example the absorbent article core of being made by cellulose fibre [gas felt (airfelt), tissue paper] and sucting wet gel material needed can fully absorb and the fluid of combining closely in several minutes.The unconjugated Excreta that has occupied space or fibre gap is very easy to flow, under pressure, can flow to rapidly on the porous egative film and be extruded or the effect at capillary force under see through egative film.

For the sanitary towel of routine, as top general description, can finish the simulation test of shoving at a high speed under the following conditions.

The surfactant of the artificial urine of test solution+1%, or

The surfactant of fluid+1% of imitative menstruation

The volume (milliliter) that shoves is 10 milliliters for sanitary towel

The speed of shoving (ml/min) 10 (in promptly 60 seconds 10 milliliters)

70 gram/the square centimeters of exerting pressure

(waiting for after 1 minute)

Dirty on the per unit square centimeter/drenched area when the result is expressed as through 5 minutes, 10 minutes, 20 minutes and 30 minutes.

Method 1b: loading simulation (Repetitive Loading Simulation) repeatedly

In this first EXPERIMENTAL DESIGN, under extremely usual loading environment (Excreta periodically and is repeatedly discharged discontinuously in the body, rather than once ejection), measure the impermeability of breathable backsheet.For the sanitary towel of routine, can under following specified conditions, finish this loading analog test repeatedly: specifically, add 5 milliliters test solution (referring to following above-mentioned) load in the central authorities of sample according to top general description.Make sample absorption test liquid 1 minute, and to this sample pressurization 5 minutes.After the above-mentioned time, measure and write down drenched size (area).Remove pressure rapidly, this sample is loaded second 5 milliliters of test solution once more.And then wait for 1 minute, and to this sample (this moment, this sample contained 10 milliliters of test solutions) pressurization 5 minutes so that sample absorbs above-mentioned test solution.After the above-mentioned time, measure and write down drenched size (area).Remove pressure immediately, this sample is loaded the 3rd 5 milliliters of test solutions again.Wait for 1 minute again so that absorb aforesaid liquid, and, measure dirty size (drenching) again this sample (this moment, this sample contained 15 milliliters of test solutions) pressurization 5 minutes.As above continue circulation, till this pad is loaded 20 milliliters.

The surfactant of the artificial urine of test solution+1% or

The surfactant of fluid+1% of imitative menstruation

The volume (milliliter) that shoves loads 5 milliliters to sanitary towel in the compartment of terrain repeatedly

20 milliliters of maximum loads

Loading speed (ml/min) 2.5 (adding 5 milliliters in promptly 2 minutes)

70 gram per centimeters of exerting pressure ²

(waiting for after 1 minute)

The result is expressed as and is loading 5 milliliters, and is 10 milliliters, dirty on the per unit square centimeter under the situation of 15 milliliters and 20 milliliters/area that drenches.

The test solution type and the volume that in test method, are adopted

In order correctly to estimate above-mentioned potential breathable backsheet design, the condition of test solution should be complementary with the final use of product.Sanitary towel designs for retaining the menstruation Excreta.For different women, this class Excreta is obviously different, contains various not commensurability fatty acids in the Excreta and from the washing dosage form dirt in the daily hygiene operation (cleaning, washing etc.).These components are very easily mobile and surface traction is very low.Now determined to adopt the imitative menstrual fluid that from Sanguis caprae seu ovis and mucin (mucine), obtains, add following surfactant can simulate the actual excremental characteristic of menstruation.The test solution volume that once shoves nearly 15 milliliters abundant, 99% of all situations of shoving in using are all dropped in this scope.Equally, can be loaded into 20 milliliters (95% sanitary towel all drops on this scope) repeatedly to the sanitary towel in using, but seldom higher.Usually, sanitary belt is loaded 10 milliliters (all pads 90%) or still less.

Though compare the incontinence patient differently with the requirement of sanitary towel, also can be used in the sanitary towel near the test solution of homaluria thing with the requirement of pad, bady's diaper or scanties lining (women is at the pad of the beginning in mid-term in menstrual period or menstrual period/dress at last).But still have dirt (fatty acid, surfactant and detergent thing) in some bodies, and determined in artificial urine, to add surfactant and service condition closely related.Owing to normal custom uses feminine hygiene articles (sanitary towel, medicated clothing lining) as light-duty incontinence patient articles for use, therefore be suitable for using the artificial urine that contains surfactant to go to estimate the performance of breathable backsheet material or structure.Should be again volume be selected the general application conditions that may exert an influence to goods with reflection.For the situation that diaper or stressed bigger incontinence patient use,, can carry out simple modification to said method in order to simulate bigger test solution loaded volume and transfer rate.

The preparation of artificial urine+1% surfactant test solution (UreaB1%)

At first prepare 10 kilograms of main batch of materials, can outwell a small amount of major ingredient if desired and add surfactant again and then make above-mentioned artificial urine test solution.Per 10 kilograms of UreaB batch of materials comprise following component:

Component molecule formula weight/10 kilograms of major ingredients

Urea (Urea) 200 grams

Sodium chloride nacl 90 grams

Magnesium sulfate MgSO ₄7H ₂O 11 grams

Calcium chloride CaCl ₂6 grams

Distilled water H ₂O 9693 grams

All reagent are " reagent grade ", can buy from standard compliant commercial chemicals suppliers.In addition, surfactant is by Pegesis, the Peosperse 200ML that U.S.A provides.For each measurement, use 90 milliliters of UreaB solution and 10 milliliters of surfactants to mix usually and 100 milliliters of UreaB/1% surfactant testing liquiies making.Should constantly stir, to guarantee using preceding said components not separate UreaB/1% solution.

Imitative menstrual fluid+1% surfactant (Artifical Menstrual Fluid

+ 1%Surfactant) the preparation of testing liquid

Imitative menstrual fluid (AMF) is based on the Sanguis caprae seu ovis of modification, in order to ensure this fluid aspect viscosity, electric conductivity, surface tension and the outward appearance and people's menstrual fluid closely similar, Sanguis caprae seu ovis has been carried out modification.In addition, in above-mentioned test solution (providing), also added surfactant (1%) so that reflect stressing conditions better by Pegesis/USA, in above-mentioned situation, general hygienic habit is (in some restricted situation, diet influence) may introduce some extra surfactants or not wish (for example) fatty acid of appearance amount, these all may reduce the surface tension of blood.The menstruation of low surface tension is to having the greatest impact as the drenched accident that sees through egative film of the breathable absorbent articles of hygienic article and so on.

Reagent:

1) through the Sanguis caprae seu ovis of defiberization (difibrinated) can buy from the U.S. Unipath S.p.A Garbagnate Milanese/Italy},

2) lactic acid of the reagent grade (85-95% w/w) of producing by Dutch J.T.Baker,

3) potassium hydroxide (KOH) of the reagent grade of producing by U.S. Sigma Chemical Co.,

4) the phosphate buffer tablet (Phosphate Buffer Saline Tablets) of the reagent grade of producing by U.S. Sigma Chemical CO.,

5) sodium chloride of the reagent grade of producing by U.S. Sigma Chemical Co.,

6) the sticking egg of producing by U.S. Sigma Chemical Co. of III type (CAS 84082-64-4) stomach

In vain,

7) distilled water.

Step 1:

By the dissolution of lactic acid powder and distilled water, make 9 ± 1% lactic acid solution.

Step 2:

The KOH powder is dissolved in makes 10% potassium hydroxide (KOH) solution in the distilled water.

Step 3:

Tablet is directly dissolved in 1 liter of distilled water of adding, make the phosphate buffered solution of pH=7.2.

Step 4:

Produce the solution that contains following component, and it slowly be heated to 45 ± 5 ℃:

460 ± 5 milliliters of phosphate buffered solution

7.5 ± 0.5 milliliter of KOH solution

Step 5:

In the solution of 4 preheatings that make (45 ± 5 ℃) set by step, add about 30 gram gastric mucins,

Make its slowly dissolving (often stirring), make mucus solution (Mucous Solution).In case dissolving,

Then this solution temperature is brought up between 50-80 ℃, and this mixture is hidden about 15 minutes.

Treat that temperature lowers, keep than stationary temperature between 40 ℃ and 50 ℃, and continue to stir 2.5 hours.

Step 6:

Above-mentioned solution is removed from heating, made solution (obtaining) be cooled to be lower than 40 ℃ by step 5.

Add 2 milliliters of solution that contain 10% lactic acid, they were fully mixed 2 minutes.

Step 7:

Above-mentioned solution is put into autoclave, and be heated to 121 ℃, kept 15 minutes.

Step 8:

Make above-mentioned solution cool to room temperature, press 1: 1 dilution proportion with the Sanguis caprae seu ovis of defiber.

After having prepared AMF, viscosity, pH and electric conductivity to it are measured, with the characteristic of guaranteeing this blood in unusual scope (referring to H.J.Bussing " Zur Biochemie deMenstrualblutes " Zbl Gynaec, 179,456 (1957)) near the ordinary month menses.The scope of its viscosity should be 7-8, and (unit: centistoke), the scope of pH value is 6.9 to 7.5, and the scope of electric conductivity is 10.5 to 13 (mmho, millmhos).If in the scope that viscosity is not stipulated, then can not adopt, need a collection of new AMF of preparation in the above.Like this, can regulate the gastric mucin amount of use on demand.Because this is natural prodcuts, a collection of component with another batch may be different.

Usually can make 100 milliliters of AMF test solutions that contain surfactant with 10 milliliters of surfactants of 90 milliliters of AMF solution (remaining on 25 ℃) adding, to be used for each time measurement.Must often stir above-mentioned AMF/1% surfactant solution, not separate with wherein component before guaranteeing to use.Should only use the solution of preparation within four hours.

Side's religious name 2: measure the fluid contact angle

The contact angle test is a kind of standard testing of estimating interactional characteristic between the surface of solids and the drop.The contact angle that drop forms on the surface reflects different interactions.Except that the interactional character of liquid-solid, contact angle is also relevant with areal deformation with the character of liquid, the surface tension of liquid, solid character.Usually, contact angle that the drop on the rough surface has greater than the smooth surface of identical chemical composition on the contact angle of drop.If the contact angle of water droplet, thinks then that this surface is hydrophobic for this liquid greater than 90 ℃.If contact angle is less than 90 ℃, this surface is hydrophilic so.

The ultimate principle of method

Liquid contact angle from the teeth outwards can be by measuring to the various technology of robust techniques more from lip-deep drop being carried out two kinds of optical analysiss.Measuring the used method of contact angle is " Wilhelmy Plate Technique ".The main points of this method are that a solid sample is suspended on the container top that fills water, reduce this sample then at leisure, make it in the water liquid depthkeeping degree really, take out this sample again.Measure the resistance (retarding force) that is subjected to when water contacts (submergence is zero) with material sample by microbalance, determine the contact cosine of an angle from following equation then:

Wherein: the sample power (milligram) when submergence is zero that F=is measured by balance;

The girth at P=sample interface place (centimetre);

ST=surface tension (dyne centimetre);

Cos φ=contact cosine of an angle;

G=is because the acceleration that gravity (in the measuring point) causes.

The instrument that is used to measure contact angle is by U.S. Cahn Instruments, automatic " dynamic contact angle analyser (Dynamic Contact AngleAnalyser) (the model DCA-322) " that Inc.Cerritos CA90701-2275 produces.For every kind of material to be evaluated (seeing Table), prepare a sample (24 millimeters * 30 millimeters), and according to description of equipment, with sample attached on the slides (glass slide).Must be very careful when putting into, do not run into material sample with assurance, otherwise the material surface of may making dirty.To every kind of Materials Measurement five times,, make the minimum that influences of the individual opposite sex of production or surface irregularity with the accuracy of guaranteeing to measure.

Table 1

Surface contact angle to the surface (will reduce capillary processing subsequently) of commercially available material is measured.

Embodiment	The surface	Untreated contact angle	Contact angle after the processing
				A B C	The chipware tissue paper, supplier: Walkisoft Denmark, Metmar Kotkar ldpe film, code name X-1522 supplier: U.S. Tredegar ldpe film, the treated supplier in code name X-1522-both sides: by U.S. Tredegar	～zero 102 102	131 121 144
D	Ldpe film, code name X1522 but puncherless: the Tredegar film product, provide by B.V.Holland, two surfaces are treated	80	103
				E	LDPE+ siloxanes (8%) thin film (puncherless): Tredegar film product, provided by B.V.Holland, two surfaces are treated	92	na
F G	LDPE+ siloxanes (16%) thin film: two treated Tredegar film products in surface, provide by B.V.Holland, polytetrafluoroethylene film (bar, puncherless), provide by U.S. 3M Corp.	102 130	na na

The situation of the contact angle of lip-deep liquid and porous material or character, liquid and surface interaction by capillarity or the ability that transmits liquid by extrusion process and areal deformation or surface texture, liquid and the mechanism of transmission are relevant.Employed test solution is to have high-hydrophilic and big capillary distilled water in this test.The contact angle that it produced is greater than common that occur or wish the contact angle that occurs with menstrual fluid or urine type Excreta.Therefore, the observation of listing in detail in the table that the result of contact must be very careful fully relatively.The contact angle of water is greater than 90 ℃ and do not mean that the material hole crack applies negative capillary force (a negative capillary force) to menstruation class Excreta.Certainly, contact angle increases and will reduce liquid transmits (or based on capillarity or based on squeezing action) by above-mentioned material degree/efficient.

Na=is not suitable for, and the contact angle of material is very big.

The result of the test that table 2 is drenched

Embodiment	Test solution	The test design	Drenched (square centimeter) is unprocessed	Drenched (square centimeter) is treated *
					1 2 3 4 5	UreaB/1％ AMF/1％ AMF/1％ UreaB/1％ AMF/1％ AMF/1％ UreaB/1％ AMF/1％ AMF/1％ UreaB/1％ AMF/1％ AMF/1％ UreaB/1％ AMF/1％ AMF/1％	1a 1a 1b 1a 1a 1b 1a 1a 1b 1a 1a 1b 1a 1a 1b	41 70 90 41 70 90 41 70 90 na na na 18 30 40	---00 20 1.3 16 31 3 11 35 007

Side's religious name 3: folk prescription is to flow test:

Folk prescription to each surface that flow test is used for quantitatively determining porous membrane to body in excremental directed flow ability.As below will describing in detail, this method can be used for the component by simple change test solution, directly measures porous each surface to excremental mobility status in the various bodies.

The ultimate principle of this method:

This test mainly is in order to estimate the conveying function of perforated membrane to unidirectional/one direction of Excreta liquid in the imitative body." good perforated membrane " is a kind of like this thin film, and it can carry out tangible fluid transmission from a surface to other surface, but along not transmitting in the other direction, again that thin film is reverse, and repeat this test.Obviously, except that transmitting fluidic directivity difference, " good perforated membrane " on the direction that is used for the breathable backsheet member time, the fluid of transmission should be minimum.

For the orientation of estimating perforated membrane transmits the speed of liquid, can carry out following simple experiment: the moisture-absorbent member that liquid has been reached saturation is placed on the top of the perforated membrane on the blotting paper top that is in a folded moisture absorption.On whole assembly (saturated hygroscopic material, thin film and blotting paper), exert pressure, measure the test solution amount that is sent on the blotting paper and absorbs by blotting paper by this perforated membrane.In test for the second time, oppositely and repeat above-mentioned test with this film.Record and evaluation are by surface 1 and surface 2 amount of liquid that transmitted.

Specifically, be of a size of one of 12 centimetres of 12 cm x to 10 and fold commercially available filter paper/blotting papers { by Type Abssorbente Bianca " N30 " (the local Ditta Bragiola SpA.Perugia of distributors of Italian Cartiera Favini S.p.A production, Italy) } weigh, and testing stand is directly lain in the below of the weight that is suspending in midair.On stacking blotting paper, this places a porous membrane sample (on two surfaces, putting on 1 and 2 respectively artificially) that is of a size of 8.5 centimetres of 8.5 cm x to be determined.The abundant saturated hygroscopic material of placement one deck on perforated membrane.This hygroscopic material by two-layer commercially available quantitatively be that the air lay moisture absorption tissue paper of 63 gram/square metre (gsm) (every layers) is formed, above-mentioned tissue paper can be from Walkisoft, Denmark, supplier's code name is buied for Metmar Kotka place, and this material absorbs the absorbent article core that liquid has reached saturation in order to simulation.Every layer of this tissue paper is of a size of 5 centimetres of 5 cm x.The placement that is mutually symmetrical of the top of every layer of paper.Then above-mentioned tissue paper member was immersed fully in the artificial urine (referring to the solution that describes in detail in the method 1) 1 minute, saturated fully to guarantee.

From liquid, take out tissue paper, keep plumbness to reach 60 seconds it, so that drop removes unnecessary fluid before being placed directly in it above perforated membrane.Saturated tissue paper is placed on the central authorities of perforated membrane, and above-mentioned perforated membrane then is placed on the central authorities of blotting paper lamination.

Final stage in test, a lucite (being of a size of 8.5 centimetres of 8.5 cm x) is placed on the center on above-mentioned saturated tissue paper member top, automatically weight is reduced on the sample, the pressure that applies 130 gram/square centimeters reaches 60 seconds, by a simple electronic machine reduction and the time of weight are controlled, with the repeatability of guaranteeing that previous test and next time test.

The pressure that is applied on the whole assembly (saturated hygroscopic material, thin film and blotting paper) is extruded into the liquid in the saturated tissue paper on the thin film, and the directivity that transmits liquid by perforated membrane helps flow of liquid and crosses thin film and absorbed by blotting paper.When removing weight, with each layer separately, check whether blotting paper weighs by liquid wets and to it.Poor (test front/rear) of record weight also compares with test second time that the direction of perforated membrane is reverse, measures the amount that goes up by this perforated membrane transmission liquid in the other direction.

Table 3:

Perforated membrane and the alternative material buied from each company are tested, and its result lists in the table 3 in detail.

Material	Test solution	Surface	1 is drenched	Surface 2 is drenched	Surface treated 2 is drenched
						Embodiment 1: CPT (LDPE) supplier code name: X-1522 Tredegar Corporation USA	UreaB/0％ AMF/0％	2.5 1.4	1.8 0.8	3 gram/square metre siloxanes 1.1 0.6
Embodiment 2: CPT (HDPE) supplier code name: 15112 Tredegar Corporation USA	UreaB/0％ AMF/0％	2.3 1.3	0.8 0.5	3 gram/square metre siloxanes 0.5 0.3
					Embodiment 3: the air lay tissue paper is (two-layer, every layer quantitatively be 63 the gram/square metre) supplier's code name: Metmar Kotka, Walkisoft Denmark	UreaB/0％ AMF/0％	2.7 1.7	2.7 1.7	5g/m 2Siloxanes is only in lower floor 1.1 0.8

Testing liquid: The preparation of test solution Urea B/0%

The preparation of the artificial urine Urea of test solution B/0% does not add in test solution the surfactant, and is identical with the artificial urine Urea of test solution B/0%.

Side's religious name 4: the mensuration of aperture area

To be designed to be communicated with for holding from waste from bodies of animals and being the disposable product that feature designs with the breathable backsheet with outside air and water vapour.The degree of this process or efficient (with regard to the interests of consumer) are relevant with the aperture area of disposable product breathable backsheet, especially with near health or to the sealing sensitive part aperture area relevant.In this test,, estimate the aperture area of liquid egative film according to two local levels and an average level of reflection entire product.

The ultimate principle of this method

Can or be combined into two kinds of materials of breathable backsheet member or include breathable backsheet or the absorbent device of member carries out the mensuration of aperture area assembling.

Material: the calculating of material aperture area is fairly simple clear.Material sample is preferably in microscopically and observes, and expansion (expended) image or the still picture of record microscopically.Above-mentioned image is placed on a millimeter (mm) graph paper then, so that calculate every square centimeter the hole count and the area in each hole easily.In addition, also can carry out digital scanning, to determine every square centimeter the hole count and the area in hole to image.In the analysis below with the gross area divided by each hole area with just can determine aperture area simply.

Absorbent device: the aperture area that contains the absorbent device of breathable backsheet mainly is used in regional interior " main opening area (Principal open area) " rating method that expectation and surrounding effectively be communicated with and definite.Only the breathability of estimating the zone that is considered to not too important is estimated, only a part that is worth as entire product " average aperture area ".For example, in absorbent device, directly can not have breathability to those zones that sealing skin (skin occlusion) exerts an influence in contact or the absorbent device, but these zones should be as the part of " main opening area " calculating.

Step 1:

At microscopically product is checked,, then quantitative analysis and graduation are carried out in these zones if there are some different zones of voidage.If there are some different zones of permeability, hope only is defined as certain permeability zones or impermeability zone usually.But if not this situation then tackles each district and makes labelling, so that the evaluation of back.

Step 2:

Expansion (expended) image or still picture to each zone obtains at microscopically are placed on above-mentioned image on a millimeter (mm) graph paper, also determine every square centimeter hole count with the area that calculates each hole easily.Can determine aperture area with the gross area simply divided by each hole area sum in the analytic process below:

Each regional different porosities or breathability are carried out above-mentioned analysis continuously.

Calculate " the average aperture area " of entire product then.

Step 3:

The regional aperture area that " main opening area " just calculates in step 2, this class aperture area appear in the pad to be estimated in those zones that the advantage to the absorbent device that uses breathability has a significant impact.This evaluation to main or sub area is subjective, but in available two kinds of methods any carries out:

Method 1: try above-mentioned articles for use (for example wearing sanitary towel or light-duty incontinence patient articles for use) on by one group of wearer representative, the articles for use that cling to the body and may seal (occlusion) are estimated with the women.These zones are estimated as main region, if the arbitrary regional mediella in these zones is porous, then it should be categorized as " main opening area " district.

Method 2: in order to understand the characteristics of wearing, from one group with pad is compressed concrete articles for use feature (as measuring flexibility, articles for use size, thickness etc.) the corresponding database analytical method (a databank analysis) that makes it adaptive with health is pure estimates above-mentioned articles for use technically.From above-mentioned pure technical Analysis, can determine main or secondary regions.

Can test from perforated membrane sample and alternative material that each company buys current, detailed results is listed in the table 4.

Table 4

Embodiment	Material	Atresia cattle/square centimeter (N/sqcm)	Average hole area	Aperture area %
					1	CPT (LDPE) supplier code name: X-1522 Tredegar, Corporation USA	110 surperficial 1 surfaces 2	0.43 0.13	～47 ～14
2	EVA-HEX supplier code name: 4017050 Tredegar, Corporation USA	99 surperficial 1 surfaces 2	0.42 0.16	～42 ～16
					3	CPT (LDPE) supplier code name: X-15112 Tredegar, Corporation USA	110 surperficial 1 surfaces 2	0.45 0.16	～49 ～18

Above-mentioned thin film is the three-dimension film with bellmouth, and therefore the size in each lip-deep hole is obviously different.Surface 1 when being defined as the breathable backsheet material towards wearer's surface.

Claims (23)

1. disposable absorbent article, it comprises: saturating liquid top flat, absorbent article core and egative film, described absorbent article core between described top flat and described egative film, described egative film comprise one outer and one towards the absorbent article core folk prescription to the fluidic liquid thin polymer film of transmission, described absorbent article core comprises that a fluid stores layer

Described absorbent article core and egative film comprise one deck at least respectively, described absorbent article core and egative film all have one towards wearer surface and towards the medicated clothing surface, described all have a fluid contact angle towards the wearer is surperficial and described towards the medicated clothing surface; And

Described absorbent device have from and comprise described fluid storage layer towards the medicated clothing face to and comprise egative film described outer field towards the medicated clothing face extend than lower part,

Wherein in than lower part at least one towards the fluid contact angle on wearer surface greater than adjacent described fluid contact angle towards the medicated clothing surface.

2. disposable absorbent article as claimed in claim 1, wherein disposable absorbent article comprises low-surface-energy material than lower part.

3. disposable absorbent article as claimed in claim 2, wherein said low-surface-energy material is selected from the mixture of curable siloxanes, fluoropolymer, Hydrocarbon and different silicones.

4. disposable absorbent article as claimed in claim 2 wherein comprises at least 5% low-surface-energy material of the gross weight of described layer than lower part.

5. disposable absorbent article as claimed in claim 2, wherein disposable absorbent article than every square metre of egative film in the lower part comprise towards the medicated clothing surface at least 0.25 the gram siloxanes.

6. disposable absorbent article as claimed in claim 1, wherein said egative film comprises two-layer, ground floor comprises thin polymer film and the second layer comprises the skin with gas-pervious fiber fabric layer, the contiguous described absorbent article core of described ground floor.

7. disposable absorbent article as claimed in claim 1, wherein said absorbent article core comprises at least two parts, and first comprises described storage layer, and second portion comprises fibrous layer, the contiguous described egative film of this fibrous layer.

8. disposable absorbent article as claimed in claim 1, wherein absorbent article core provides at least 10 ° surface energy gradient towards the fluid contact angle between the wearer surface of medicated clothing surface and egative film.

9. disposable absorbent article as claimed in claim 8, wherein said fluid contact angle is bigger at least 20 ° than the fluid contact angle of adjacently situated surfaces.

10. disposable absorbent article as claimed in claim 1, the described described fluid contact angle towards the medicated clothing surface of wherein said absorbent article core is at least 90 °.

11. disposable absorbent article as claimed in claim 1, wherein said absorbent device has continuous fluid contact angle gradient described in than lower part.

12. disposable absorbent article as claimed in claim 1, wherein said articles for use are sanitary towel or scanties lining.

13. disposable absorbent article, it comprises: saturating liquid top flat, absorbent article core and egative film, described absorbent article core is between described top flat and described egative film, described egative film comprise one outer and one towards the absorbent article core folk prescription to the fluidic liquid thin polymer film of transmission, described absorbent article core comprises that a fluid stores layer

Described absorbent article core and egative film comprise one deck at least respectively, described absorbent article core and egative film all have one towards wearer surface and towards the medicated clothing surface, described all have a fluid contact angle towards the wearer is surperficial and described towards the medicated clothing surface; And

Described absorbent device have from and comprise described fluid storage layer towards the medicated clothing face to and comprise egative film described outer field towards the medicated clothing face extend than lower part,

Wherein described than the one deck at least in the layer described in the lower part towards the fluid contact angle of medicated clothing face greater than described fluid contact angle towards the wearer surface with one deck.

14. disposable absorbent article as claimed in claim 13, wherein disposable absorbent article comprises low-surface-energy material than lower part.

15. disposable absorbent article as claimed in claim 13, wherein said low-surface-energy material is selected from the mixture of curable siloxanes, fluoropolymer, Hydrocarbon and different silicones.

16. disposable absorbent article as claimed in claim 14, wherein disposable absorbent article than every square metre of egative film in the lower part comprise towards the medicated clothing surface at least 0.25 the gram siloxanes.

17. disposable absorbent article as claimed in claim 13, wherein said egative film comprises two-layer, and ground floor comprises thin polymer film and the second layer comprises the skin with gas-pervious fiber fabric layer, the contiguous described absorbent article core of described ground floor.

18. disposable absorbent article as claimed in claim 13, wherein said absorbent article core comprises at least two parts, and first comprises described storage layer, and second portion comprises fibrous layer, the contiguous described egative film of this fibrous layer.

19. disposable absorbent article as claimed in claim 13, wherein absorbent article core provides at least 10 ° surface energy gradient towards the fluid contact angle between the wearer surface of medicated clothing surface and egative film.

20. disposable absorbent article as claimed in claim 19, wherein said fluid contact angle is bigger at least 20 ° than the fluid contact angle of adjacently situated surfaces.

21. disposable absorbent article as claimed in claim 13, the described described fluid contact angle towards the medicated clothing surface of wherein said fluid storage layer is at least 90 °.

22. disposable absorbent article as claimed in claim 13, wherein said absorbent device has continuous fluid contact angle gradient described in than lower part.

23. disposable absorbent article as claimed in claim 13, wherein said articles for use are sanitary towel or scanties lining.

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