RU2358704C1 - Underwear piece containing elastic laminate - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: panties-like underwear piece (10) contains a front (12), back (14), crotch (16) areas and a waist area (18). The specified piece (10) has longitudinal (y) and cross (x) direction. At least part of the piece (10) contains an elastic laminate (20) formed from first (22) and second (24) layers of fibrous material and elastic film (26) layer between specified first and the second fibrous layers (22; 24). Said laminate (20) has puncture resistance at least 15 H.

EFFECT: invention is applicable to put on and take off the piece without puncturing, e g with fingernails.

15 cl, 5 dwg, 3 tbl

Description

Technical field

The present invention relates to a panty-shaped article of underwear, said article comprising a front, back, crotch and waist region. At least part of the product contains an elastic laminate composed of two layers of fibrous material and a layer of elastic film located between the fibrous layers.

BACKGROUND OF THE INVENTION

It is known to use reusable underwear such as underpants to hold disposable absorbent core parts in place on an incontinence user. Disposable absorbent body parts may be sanitary napkins or incontinence products. This approach has advantages over traditional absorbent articles with a whole absorbent core, such as diapers or panties used for incontinence, in that only the absorbent component of the article is removed after contamination, while the underwear component can be reused, thereby providing savings in production costs, and materials.

Materials such as laminates are known as components of absorbent articles, such as diapers. For example, WO 03/047488 discloses an elastic laminate comprising an elastic film that is connected at opposite ends to the first and second inelastic fibrous layers. Laminate is made by bonding inelastic fibrous layers with a layer of elastic film and subsequent stretching of the composite material, causing the destruction of inelastic materials. The elastic film material may be of breathable material. Laminate may be incorporated into an absorbent article, such as a diaper. No puncture resistance of such material is mentioned. The method described in WO 03/047488 will produce a material that is soft and elastic, but which on the other hand has a low puncture resistance, since the destroyed outer nonwoven layers do not contribute to the puncture resistance of the laminate.

EP 0861647 discloses a lingerie system comprising a reusable portion of underpants and an absorbent pad to be replaced. Briefs consist of a three-layer laminate, which contains a membrane film as an intermediate layer between two textile structures.

Elastic materials, such as stretch-related laminates, are also known. Such laminates may include a layer of expanded elastomeric fibers that are stretched and inserted between the outer layers of the spun nets.

US 2003/0022582 describes a laminate in which an elastomeric film is bonded between two or more layers of nonwoven meshes. It is argued that the laminate is particularly suitable in the elastomeric “ears” of diapers, which allow the diaper to stretch to fit users of various sizes. It has been found that non-woven materials provide little or no puncture resistance, therefore, any puncture resistance that the laminate has will almost exclusively depend on the puncture resistance of the elastomeric film.

However, there is still the opportunity to improve the properties of articles in the form of underwear used in two-component systems. The consumer places high demands on the convenience, fit and feel of imitating clothes for underwear such as underpants. Discreteness of the product is also a priority, since the underwear should be thin, preferably equal in thickness to a pair of ordinary cotton underpants. In addition, it is highly desirable that the absorbent body is correctly held in relation to the body of the wearer using an undergarment so as to be optimally positioned to receive physiological exudates and to avoid unwanted slipping or movement of the absorbent body. The underwear itself is intended to be reused and therefore requires washing. Therefore, it must be able to withstand without destruction the elevated temperatures, water, detergents and mechanical shaking that are present in modern washing and / or drying machines. Therefore, there is a need to improve the strength of articles in the form of underwear, especially their puncture resistance.

The task and the most important features of the invention

The objective of the present invention is to provide a product in the form of a panty-shaped underwear that combines the properties of comfort and fit to the user's body and softness, and the sensation of imitation of clothing, close to textile materials. It is further desirable that the product can be worn and removed without a puncture, for example, with fingernails. This is an important feature, since the force that can be applied while putting on or taking off such a product is estimated to be equal to 5 N. The object of the invention is also that the product must withstand machine wash and drying and remain intact. These and additional tasks in accordance with the invention are achieved by a panty-shaped article of underwear having a front, back and crotch regions and a waist region, wherein at least a portion of said article comprises an elastic laminate composed of the first and second layers of fibrous material and a layer of elastic film located between said first and second fibrous layers. In accordance with the invention, the elastic laminate has a puncture resistance of at least 15 N.

Thanks to the materials and methods used in its construction, the puncture resistance of this laminate is higher than just the layer of elastic film (i.e. layers of fibrous material contribute to the puncture resistance of the laminate). The product in the form of an underwear provides a good fit due to the elasticity of the laminate and a feeling of imitation of fabric. In addition, the product in the form of an underwear is reusable and can withstand machine wash / dry, even machine wash up to 60 ° C. The use of the laminate allows the product to withstand machine wash at least three times at temperatures up to 60 ° C during the wash cycle of the washing machine and still remain intact. A garment in the form of an undergarment can be used to securely hold individual absorbent body parts (e.g., sanitary napkins or incontinence products) in place with respect to the wearer's body, although it is not permanently attached to such absorbent body parts. The elastic properties of the laminate ensure that the absorbent core parts are held securely in relation to the wearer's body.

Preferably, the elastic laminate has a puncture strength of at least 20 N, more preferably at least 30 N.

In one embodiment, at least the front region of the article comprises an elastic laminate. In addition, both the front and rear areas of the product may contain an elastic laminate. In another embodiment, a substantial portion of the crotch area of the article is free of elastic laminate. In addition, the waist area of the article may be free of elastic laminate. In a separate embodiment, the entire product comprises an elastic laminate.

Preferably, the elastic film layer is breathable. The elastic laminate suitably has a Water Vapor Transmission Rate in accordance with Method D of ASTM E96-00 of at least 1,500 g / m ² 24 hours, preferably at least 3,000 g / m ² 24 hours

In one embodiment, the elastic laminate has a lateral elasticity of the product of at least 30%, preferably at least 50%, more preferably at least 70% when measured in accordance with the elasticity test described herein. Elasticity in the transverse direction of the product allows a product of the same size to be used on users with different waist sizes. At least one of the layers of fibrous material may have an elongation at maximum load greater than the elasticity of the elastic laminate. In addition, both layers of fibrous material can have an elongation at maximum load greater than the elasticity of the elastic laminate.

In accordance with one embodiment of the present invention, the layers of fibrous material have an elongation at maximum load of at least 10%, preferably at least 20% more than the elasticity of the elastic laminate. The first and / or second layers of fibrous material preferably contain a mixture of polymers of polypropylene and polyethylene.

In a most preferred embodiment, the elastic laminate comprises first and second fibrous layers of spun material, each having a bulk of between 10 and 35 g / m ² , preferably between 12 and 30 g / m ² , more preferably between 15 and 25 g / m ² and the breathable layer of the elastic film has a bulk of between 20 and 100 g / m ² , preferably between 20 and 60 g / m ² , wherein said elastic laminate has a Water Vapor Transmission Rate in accordance with ASTM E96-00 Method D of at least 1500 g / m ² 24 h, preferably at least 3000 g / m ² 24 h.

Description of figures

Figure 1 shows a perspective view of an item of underwear in the form of underpants.

Figure 2 shows a simplified top view of a product in the form of a panty-type underwear in its flat uncompressed state prior to formation.

Figure 3 is a cross section of an elastic laminate in accordance with the invention.

Figure 4 is a graph showing the dependence of tension on load for two non-woven fibrous layers.

Figure 5 is a graph showing the dependence of tension on load for an elastic laminate.

Description of preferred embodiments

The invention will now be described in more detail with reference to some embodiments shown in the accompanying drawings.

The figures show the embodiment of the article (10) in the form of a panty-shaped underwear. The article typically comprises a front 12, a back 14, and a crotch 16 region and a waist region 18. The front region 12 is one which, when used, surrounds the user's stomach. The waist area 18 is one that surrounds the user's waist when using the product. The back region 14 is one that covers the lower torso / buttock of the user when using the product. The crotch area 16 is defined as the narrow part of the product intended for use in the user's gusset between the legs. The product 10 has a longitudinal (y) and transverse direction (x).

Thus, the product is divided into four areas (front region 12, rear region 14, crotch region 16 and waist region 18) in its longitudinal direction, as shown in Figure 2. The front region is limited by the edge of the product, on which the waist region ends, longitudinal side the edges of the product, the part of the product’s leg openings and the transverse line (a), which is located at the point at which the angle of the edge of the leg opening changes most vertically (i.e., at the point at which the rate of change of the angle of the edge of the leg opening relative to to the transverse direction is the highest). The back region is limited in the same way: the edge of the article at which the waist ends, the longitudinal side edges of the article, part of the product’s leg openings and the transverse line (b), which is located at a point on the edge of the leg’s opening, in which the edge angle changes most vertically (i.e., at the point at which the rate of change of the angle of the edge of the leg opening with respect to the transverse direction is the highest). The gusset region is limited at its longitudinal edges by the edges of the product leg openings and at its transverse edges by the two transverse lines (a) and (b) described above.

Elastic laminate

At least a portion of the article 10 comprises an elastic laminate 20 made up of first 22 and second 24 layers of fibrous material and a layer 26 of elastic film located between said first and second fibrous layers 22; 24. Characteristically, the elastic laminate 20 has a puncture resistance of at least 15 N. Preferably, the elastic laminate 20 has a puncture resistance of at least 20 N, more preferably at least 30 N.

The laminate is flexible at least in the transverse X-direction of the product. The X-direction elasticity should be at least 30%, preferably at least 50%, more preferably at least 70%, as measured by the elasticity test below.

The elastic laminate 20 consists of the first and second outer layers of fibrous material 22 and 24 and the middle layer 13 of the elastic film located between these fibrous layers. The outer fibrous layers 22 and 24 are selected so that they, in combination with the inner layer of the elastic film, give the laminate good puncture resistance. They also provide the laminate with softness and a sense of imitation of clothing. Examples of suitable materials are carded webs and spun materials. The bulk of the layers of fibrous materials should be between 10 and 35 g / m ² , preferably between 12 and 30 g / m ² , more preferably between 15 and 25 g / m ² . Examples of suitable polymers used in fibrous materials are polyethylene, polyesters, polypropylene and other polyolefin homopolymers and copolymers. Natural fibers, such as cotton fiber, can also be used as long as they provide the desired properties. A mixture of polymers can contribute to higher flexibility of the nonwoven layer and thereby gives the nonwoven material a higher elongation at maximum load. It has been proven that a mixture of polymers of polyethylene and polypropylene provides good results in this regard. A mixture of fibers of various polymers is also possible.

The middle layer 26 of the elastic film in accordance with one embodiment of the invention is an aperture elastic film having a bulk of between 20 and 100 g / m ² , preferably between 20 and 60 g / m ² . The film may be from any suitable flexible polymer, natural or synthetic. Some examples of suitable materials for an elastic film are low crystallinity polyethylene, low crystallinity polyethylene on a metallocene catalyst, ethylene vinyl acetate (EVA) copolymers, polyurethane, polyisoprene, butadiene and styrene copolymers, styrene block copolymers such as styrene, isoprene and block copolymers styrene (SIS), styrene, butadiene and styrene (SBS) or styrene, ethylene-butadiene and styrene. You can also use mixtures of these polymers, as well as other modified elastomeric or non-elastomeric materials. One example of a suitable film is the aperture three-layer elastomeric film PE-SEBS-PE.

As mentioned previously, the elastic film layer 26 may be breathable. This gives a high degree of convenience to the user, since the accumulation of moisture / sputum is reduced or can be completely avoided. The breathability of the elastic film layer 26 can be quantified using the Water Vapor Transmission Rate (WVTR) in accordance with ASTM E96-00 Method D. In accordance with one embodiment, the elastic laminate 20 has a Water vapor transmission rate of at least 1,500 g / m ² 24 h, preferably at least 3,000 g / m ² 24 h, as measured using the ASTM method above.

The elastic laminate 20 can be made in accordance with a modified version of the method disclosed in WO 03/047488, in which one spun layer 22 is applied to the film 26 in an adhesive state and thereby adheres to the film layer, while the other spun layer 24 is adhesive laminated with a film layer 26 using, for example, a pressure sensitive hot melt adhesive. The modification includes the stepwise stretching of the laminate (via hooking devices, IMG) to a point below the elongation at peak load of at least one of the inelastic nonwoven layers to maintain some strength for at least one of the nonwoven layers. Another layer can also be stretched to a point below its elongation at peak load or to a point at which it will tear during stretching.

The method described in WO 03/047488 involves stretching the laminate over the fracture point of the fibrous material so that the inelastic layers completely collapse. Therefore, as described in WO 03/047488, the extension of the laminate is not limited to the tensile modulus of the inelastic material.

In contrast to the method described in WO 03/047488, in the manufacture of a laminate in accordance with the present invention, at least one, preferably both of the fibrous layers that bind to the elastic film does not completely break. The choice of fibrous materials that have an elongation at maximum load greater than the elasticity of the elastic laminate allows the elastic film to stretch without obstruction from the fibrous layers. This selection also ensures that the fibrous layers contribute to the resistance to puncture of the laminate, as they do not completely delaminate or break during manufacture. Therefore, at least one, alternatively, both layers of fibrous material 22, 24 can have an elongation at maximum load greater than the elasticity of the elastic laminate 20. Preferably, the layers of fibrous material 22; 24 or at least one of the fibrous layers have an elongation at maximum load, which is at least 10%, preferably at least 20% more than the elasticity of the laminate 20.

According to a most preferred embodiment of the invention, the elastic laminate 20 comprises first and second fibrous layers 22, 24 of spun material, each having a bulk of between 10 and 35 g / m ² , preferably between 12 and 30 g / m ² , more preferably between 15 and 25 g / m ² and the breathable layer 26 of the elastic film has a bulk of between 20 and 100 g / m ² , preferably between 20 and 60 g / m ² . The elastic laminate 20 in accordance with this embodiment has a Water Vapor Transmission Rate in accordance with ASTM E96-00 Method D of at least 1,500 g / m ² 24 hours, preferably at least 3,000 g / m ² 24 hours.

Figure 4 shows the behavior of two nonwoven layers of 20 g / m ² and 25 g / m ² (BBA Sofspan 200) in tension. It can be seen that as the load increases (in Newtons), the voltage in the layer increases slowly at first and then more rapidly. The applied load eventually reaches a maximum (“maximum load”), at which point the load drops rapidly, as the material is destroyed. You can see that for a layer of 20 g / m ^{2 the} maximum load is achieved at approximately 90% voltage, while for a layer of 25 g / m ^{2 the} maximum load is achieved at approximately 150% voltage.

Figure 5 exerts the behavior of a laminate in accordance with the present invention under tension under constant tension. The laminate contains 25 g / m ² Sofspan NW from BBA on both sides of a 40 g / m ² aperture elastic film, where one side is a laminated glue with approximately 5 g / m ² glue.

From zero stress, the laminate exhibits elastic behavior in region (A) to approximately “bend point” (B), after which the load rapidly increases in region (C). The bend point (B) is defined as the first point on the load-voltage curve, at which the gradient becomes more than 0.3 N /%. The laminate shown is elastic to a stress of about 80%, since it is less than the elongation (stress) at the maximum load of the nonwoven layer (approximately 150% in FIG. 5), the laminate is within the scope of the present invention.

The applied load ultimately reaches a maximum (“maximum load”, D), at which point the gradient of the load-voltage curve is zero. The load then drops in region (E), as the material is destroyed. Complete destruction of the laminate occurs at point (F).

Preferably, the elastic laminate 20 has air permeability (Water vapor Transmission Rate) in accordance with ASTM E96-00 Method D of at least 1,500 g / m ² 24 hours, preferably at least 3,000 g / m ² 24 hours

The opacity of the material layer is a typical ability of the material layer to hide visually from the side of the underlying object or pattern. Opacity is measured as a percentage, where 100% opacity means that nothing can be seen through the material layer, and 0% means that the material layer is completely transparent. The opacity is measured using the opacity test described below, which is based on the data of the index of reflection of light. The elastic web material has an opacity of at least 40%, preferably at least 50%, and more preferably at least 60%. The opacity of the elastic web material gives the product a clothing-like appearance, which is especially important when the product is a panty type underwear. Especially in this case, when the elastic roll material forms a single component over large areas of the front and back regions, the appearance of the elastic roll material is especially important for the entire appearance of the product. Thus, in the manufacture of elastic roll material opaque with at least 40% opacity, the item in the form of a panty-shaped underwear will be more like clothing and more like “ordinary” underwear than if the elastic roll material had more high degree of transparency.

Opacity can be increased with the introduction of opaque fillers in the laminate, especially in an elastic film. Such pigments may be organic or inorganic dyes, coloring agents or bleaching agents. Inorganic materials such as titanium dioxide, inorganic carbonates, synthetic carbonates, talc, nypheline syenite, magnesium hydroxide, Siatomite earth aluminum trihydrate, mica, natural or synthetic silicic acids, calcined clays and mixtures thereof are preferred examples of opaque fillers.

Filler is preferably added as a masterbatch during film extrusion. One example of a suitable concentration is about 5% by weight of filler to the weight of the film.

The live section of the elastic film layer is at least 5%, more preferably at least 8%. The live section is measured by image analysis methods and is defined as the sum of the area of the holes divided by the total area of the film sample.

Underwear-type item

The article 10 in the form of a panty-type undergarment disclosed in FIG. 1 is intended to surround the lower abdomen and gusset region of the user. It comprises a front 12, rear 14 and crotch 16 regions and a waist region 18. The front 12 and rear 14 regions are connected to each other along their longitudinal edges at side seams 28, which may include ultrasonic welding, gluing, or the like.

The entire article 10 may comprise an elastic laminate 20. Preferably, at least the front region 12 of the article 10 comprises an elastic laminate 20. In addition, both the front and rear regions 12; 14 articles may comprise an elastic laminate 20.

According to a preferred embodiment, a substantial portion of the crotch region 16 of the article is free of elastic laminate 20. The “substantial portion” used herein refers to at least 50%, preferably at least 75%. If the crotch region 16 does not contain an elastic laminate 20, it may contain non-woven material or breathable film material. This embodiment allows improved comfort and breathability of the product on the gusset region. Alternatively, the crotch region 16 may comprise an elastic film laminate other than the elastic laminate 20 used on the rest of the article. As a further alternative, the crotch region 16 may comprise a plastic film material that may be airtight.

Preferably also, the waist region 18 of the article is free of elastic laminate. The waist region 18 may comprise a nonwoven material that is elasticized by elastic elements 30, such as elastic threads, compressively attached between layers of materials such as nonwoven materials. Similar elastic elements 30 can also be arranged around the leg openings of the article. Ultrasonic welding, bonding or the like attaches the elastic laminate 20 to the elasticized nonwoven material at the waist area 18.

There is no need for additional elasticized side parts connecting the front and back regions 12 and 14 when using the elastic laminate 20 in accordance with the invention. If desired, additional elasticized side parts can of course be provided, especially in cases where the elastic laminate 20 is located only on parts of the front and / or back regions.

The elastic laminate must have a puncture strength of at least 15 N, as measured in accordance with ASTM designation D3763-02. Preferably, the elastic laminate of the present invention has a puncture strength of at least 20 N and more preferably at least 30 N.

The elastic laminate should preferably have softness in accordance with Kawabata of at least 20, preferably at least 30, and most preferably at least 40.

It is further desirable that it has a formability according to Kawabata of not more than 50, preferably not more than 30, more preferably not more than 20 and most preferably not more than 10.

It is also desirable that the elastic laminate have a drape in accordance with Kawabata of not more than 40.

Description of test methods

Opacity

The opacity of the elastic net material is measured in accordance with a slightly modified version of the Swedish Standards Institute SS-ISO 2471: 1998 (Diffuse Reflection Method). The method was originally designed to measure the opacity of sheets of paper, but it also works well for measuring the opacity of other types of sheet-shaped materials, such as elastic laminates in accordance with this invention. Opacity is measured on the unstretched state of the elastic mesh material. The principle of the test method is to measure the Light Reflectance Coefficient of a Single Sheet, R ₀ , from a single sheet with respect to a standardized black base and the True Light Reflectance Coefficient, R _∞ , with respect to a completely opaque white base. Opacity (%) is calculated using the formula 100 · R ₀ / R _∞ .

The following modifications to the test method were made:

i) When measuring the Light Reflectance Factor of an Individual Sheet, R ₀ , black velvety fabric was used as the basis.

ii) When measuring the True Light Reflectance Coefficient, R _∞ , the measurement was carried out on one separate sheet of elastic laminate with respect to a white tile as a base.

iii) Instead of a CIE C light source (2 °), a CIE D65 light source (10 °) was used.

The measured opacity values are the average of five measurements.

Puncture resistance

Puncture resistance is measured in accordance with ASTM Designation D3763-02. From the penetration type tests, this method derives the data of the strain versus load. For each laminate, the maximum load is calculated.

Tensile Strength (Ref: ASTM D 882)

The method measures the tensile strength and elongation of various elastic materials. The tensile strength and elongation of a unique test specimen are tested using a dynamometer.

Device: Instron 4301.

Dynamometer connected to a computer.

Slider speed: 500 mm / min.

Clamp distance: 50 mm.

Sample preparation. Test specimens are cut from a whole width of material. The width of the specimen should be 25.4 mm and a length of at least 50 mm longer than the distance between the clamps, if possible. It is important that the edges of the sample are flat and without nicks. Samples are kept before testing for at least 4 hours at a relative humidity of 50% ± 5% and a temperature of 23 ° C ± 2 ° C.

Methodology The dynamometer is calibrated in accordance with the instrument instructions and set to zero. The sample is fixed and checked that it does not stand obliquely or unevenly fixed. The material is not allowed to slip when using clips covered with braid or similar material. The dynamometer starts to work and stops after a break in the material (if there is no automatic control). Measurements obtained by premature failure (i.e., the sample burst at the clamp or damaged during preparation) are not taken into account whenever possible.

The following results are expressed using a dynamometer with a computer:

- maximum force, N / 25.4 mm;

- elongation at maximum effort,%;

- breaking strength, N / 25.4 mm;

- elongation at breaking strength,%;

- bend point, N /%.

Elasticity test

The method measures how an elastic material behaves during repeated loading and unloading cycles. The sample is stretched to a predetermined extension, and a cyclic movement is made between 0 and the specified predetermined extension. The desired loading and unloading forces are recorded. The residual, i.e. remaining, lengthening of relaxed material.

A Lloyd LRX dynamometer is used, capable of cyclic movements and equipped with a printer / recorder or software. The sample is obtained by cutting it to a width of 25 mm and a length that is preferably 20 mm longer than the distance between the clamps of the dynamometer.

The dynamometer is calibrated in accordance with the instrument instructions. The parameters required for the test (load and unload forces) are adjusted to:

slide speed: 500 mm / min;

distance between clips: 50 mm;

preload: 0.05 N.

The sample is placed in the clamps in accordance with the marks, and you should make sure that the sample is centered and attached perpendicular to the clamps. The dynamometer is turned on and performs three cycles between 0 and a predetermined extension equal to the highest defined 1st load. Before the last cycle, the sample “rests” for 1 minute, then the residual elongation is measured by stretching the sample until a force of 0.1 N is reached and the elongation is read.

The residual elongation after relaxation (attenuation) should be less than 10% and is measured by the above method. Thus, an elasticity of 30% is defined as the fact that the laminate should have a residual relaxation after elongation of less than 10% after exposure to an elongation of 30% in the above dynamometer. Elongation of 30% means elongation to a length that is 30% longer than the original length of the sample.

Challenges by Kawabata

The KES-FB Kawabata Test is a Japanese quality assessment system for use for textile materials and is disclosed in “The Standardization and Analysis of Hand Evaluation (2 ^nd Edition), Sueo Kawabata, July 1980, The Hand Evaluation and Standardization Committee, The Textile Machinery Society of Japan. " The test used in this invention uses two of the Kawabata test instruments, KES-FB2 for measuring bending elasticity, V (gf · cm ² / cm), and KES-FB1 for measuring shear stiffness, G (gf / cm · degree) and Elongation, EMT (%).

Bending Resistance (B) KES-FB2

The angle of inclination was measured between 0.5 cm ^-1 and 1.5 cm ^-1 and -0.5 cm ^-1 and -1.5 cm ^-1 . Measurements were performed in both directions (MD and CD) with the following settings:

total sample area: 20 × 20 cm;

maximum curvature: Kmax = ± 2.5 cm ^-1 ;

bending speed: 0.5 cm ^-1 / s;

effective sample sizes: length 20 cm and width 1 cm;

bending deformation is applied in the width direction.

Shear Stiffness (G) KES-FB1

The angle of inclination was measured between 0.5 cm ^-1 and 2.5 cm ^-1 and -0.5 cm ^-1 and -2.5 cm ^-1 . Measurements were performed in both directions (MD and CD) with the following settings:

total sample area: 20 × 20 cm;

sample voltage: W = W = 10 gf / cm;

maximum shear angle: φ = ± 8 °.

effective sample dimensions: 20 cm wide and 5 cm long;

shear strain is applied in the width direction.

Elongation Elongation (EMT )

Measurements were performed in both directions (MD and CD) with the following settings:

total sample area: 20 × 20 cm;

maximum load: Fm = 500 gf / cm;

stretching speed: 0.2 mm / s;

effective sample dimensions: 20 cm wide and 2.5 cm long;

tensile strain is applied in the length direction;

elongation exactly 50 mm / 10 V.

Softness (s)

Softness (S) according to Kawabata is obtained from the formula:

Formability (F)

Formability (F) according to Kawabata is obtained from the formula:

F = B · EMT

Drapability (D )

Drapeability (D) according to Kawabata is obtained from the formula:

D = 116 + 25 · log (B · G / W), in which W is the bulk of the sample.

Examples

Opacity

The opacity of the elastic laminate sample was measured. The sample was an elastic laminate in accordance with the invention, containing an inner aperture three-layer elastic film PE-SEBS-PE with a bulk of 36 g / m ² and two outer layers of spun material, PP (polypropylene), each having a bulk of 22 g / m ² . Laminate is obtained by a modified version of the method disclosed in WO 03/04788 and which is described above, in which one spun layer is applied to the film in an adhesive state and will thus bind to the film layer, while the other spun layer is adhesive laminated to the film layer using, for example, hot-melt adhesive, pressure-sensitive (amount of adhesive 3 g / m ² ). The laminate is incrementally stretched, and the inelastic spun layers stretch to a point below elongation at maximum load to maintain some strength in the spun layers. The elasticity of the laminate after stretching is close to the elasticity of the layer of elastic film.

The aforementioned base weights of the layers refer to the final laminate after stretching. Before stretching, the bulk of the individual layers was: the inner layer of the film 40 g / m ² , the outer spun layers 25 g / m ² each and the adhesive layer 3 g / m ² . Since it is difficult to measure the bulk of the individual words after lamination and stretching, an approximation was made from the bulk of the layers to lamination and stretching. The laminate before stretching had a bulk of 93 g / m ² , and after stretching it had a bulk of 85 g / m ² , which means a strain of about 10%. Then it was suggested that the deformation of the individual fibrous layers and the film layer is the same, i.e. about 10%.

The inner layer of the film contained 4.9 wt.% Filler in the form of TiO ₂ . The live section of the film layer was 13%.

The opacity of the laminate was about 68%.

An opacity value of at least 40% is acceptable to provide a sensation of imitation diaper clothing in the form of panties, as disclosed above, which, in significant areas of the frame, contains an elastic laminate as a single component. Preferably, the opacity should be at least 50%, more preferably at least 60%.

It is further desirable, for example, due to cost, to have a low bulk of the elastic laminate. The bulk must be 100 g / m ² or lower. The ratio of opacity and bulk is therefore also an aspect of the present invention. Preferably, this ratio should be at least 0.4, more preferably at least 0.5, and most preferably at least 0.6, where the opacity is measured in% and the bulk is measured in g / m ² .

Puncture resistance

The puncture resistance of three different samples (A, B and C) was measured in accordance with ASTM designation D3763-02 and the measurements are shown in Table 1.

Tensile strength

The puncture resistance of three different samples (A, B and C) was measured in accordance with the method given above, and the measurements are shown in Table 1.

Elasticity

The elasticity of three different samples (A, B and C) was measured in accordance with the method described above, and the measurements are shown in Table 1.

Sample A is an elastic laminate according to WO 03/047488 with 15 g / m ² PP of spun nonwoven material on both sides of a 40 g / m ² elastic film. The spun nonwoven used is elongated at a maximum load of 60%, which is less than the elasticity of the laminate. The low puncture resistance of this material means that it falls outside the scope of the present invention.

Sample B is an elastic laminate with 25 g / m ² PP / PE spun non-woven material on both sides of a 36 g / m ² elastic film.

Sample C is an elastic laminate with one layer of 25 g / m ² PP / PE non-woven material and one layer 20 g / m ² PP / PE non-woven material on opposite sides of 36 g / m ² elastic film.

Table 1 Sample A Sample B Sample C Puncture Force (N) 12.8 49.5 40.6 The main mass (g / m ² ) 78.66 87.96 82.71 Tensile strength and elongation MD (machine direction) Tensile Strength at Maximum (MD), N / 25 mm 8.29 25.3 28.03 Elongation at break,% 269.82 311.94 691.47 Elongation at maximum / strain,% 136 111.44 109.28 CD (transverse direction) Tensile Strength at Maximum (CD), N / 25 mm 11.72 11.15 9.16 Elongation at break,% 792.87 768.19 160.15 Elongation at maximum / strain,% 74.88 124.82 134.42

Measurement of loading and unloading forces and residual elongation Tensile strength at elongation of 80% (1st cycle) 2.78 7.11 10.66 Residual Elongation (3rd cycle) 7.86 7.52 8.09 3rd Reverse Efforts At 80%, N / 25 mm 1.14 1.44 1.42 At 60%, N / 25 mm 0.82 0.85 0.8 At 40%, N / 25 mm 0.54 0.53 0.48

Challenges by Kawabata

Four different samples were measured in the Kawabata test with respect to flexural elasticity (B), shear stiffness (G), and elongation (EMT). From these measured values, softness (S), formability (F), and drape (D) were calculated.

Four samples were:

Laminate sample (SL): an elastomeric laminate according to the invention, comprising an inner aperture three-layer elastomeric film PE-SEBS-PE, a bulk of 36 g / m ² and two outer layers of spun material, PP (polypropylene), each having a bulk 22 g / m ² . Laminate is obtained by a modified version of the method disclosed in WO 03/04788 and described above, in which one spun layer is applied to the film in an adhesive state and will thus bind to the film layer, while the other spun layer is adhesive laminated to the film layer when using, for example, hot-melt adhesive, pressure-sensitive (amount of glue 3 g / m ² ). The laminate is stretched in steps, while the inelastic spun layers are stretched to a point below elongation at maximum load to maintain some strength in the spun layers. The elasticity of the laminate after stretching is close to the elasticity of the layer of elastomeric film.

The above-mentioned main masses of the layers refer to the finished laminate after stretching. Before stretching, the bulk of the individual layers was: the inner layer of the film 40 g / m ² , the outer spun layers 25 g / m ² each and the adhesive layer 3 g / m ² . Since it is difficult to measure the bulk of the individual words after lamination and stretching, an approximation was made from the bulk of the layers to lamination and stretching. The laminate before stretching had a bulk of 93 g / m ² , and after stretching it had a bulk of 85 g / m ² , which means a strain of about 10%. Then it was suggested that the deformation of the individual fibrous layers and the film layer is the same, i.e. about 10%.

Link 1: Cotton jerseys, so-called jerseys, with elastomeric yarns.

Ref. 2: Tena Discreet incontinence outer protective cowl (odor control, medium size) manufactured by SCA Hygiene Products AB. The outer protective coating contains two layers of non-woven material with parallel elastic threads between them, which crush the material.

Ref. 3: Kimberly-Clark Poise normal super outer incontinence cover material. The outer protective coating contains two layers of non-woven material with parallel elastic threads between them, which crush the material.

Climatic conditioning of the materials was carried out at 20 ° C and a relative humidity of 65% for 48 hours. For articles in the form of pants, the absorbent core was removed and the outer protective layer was pulled over the device measuring the knitted article for 24 hours and then allowed to relax under the same climatic conditions for 24 hours.

The dimensions of the samples were 10 × 10 cm.

All tests were carried out on three samples and in two directions of the material (machine direction, MD, and transverse direction, CD).

The following results were obtained.

table 2 Sample B, bending elasticity (gf · cm ² / cm) G, shear stiffness (gf / cm · degree) EMT, elongation (%) MD CD Average MD CD Average MD CD Average SL 0,095 0,022 0.059 1.46 1.38 1.42 208.4 92.0 150.2 Link 1 0,03 0,03 0,03 0.58 0.64 0.61 160.6 173.2 166.9 Link 2 1.05 0.09 0.57 0.87 0.68 0.77 23.9 211.7 117.8 Link 3 1,53 0.04 0.78 1.74 1.21 1.47 26.28 195.3 110.8

From these results, softness (S), drape (D) and formability (F) were calculated in accordance with Kawabata in accordance with the formulas above. These results are summarized in Table 3 below.

Table 3 Sample

Softness (s)

Drapability (D) 116 + 25 log (BG / W) Formability (F) V · EMT The main mass (W), g / m ² SL fifty 40 9 88 Link 1 75 13 5 231 Link 2 fourteen 45 67 160 Link 3 12 51 87 133

The results should be understood as follows.

Softness (S): A higher value indicates softer material.

Drapeability (D): A higher value indicates stiffer material.

Formability (F): A higher value indicates that the material is less formable.

An experienced laminate according to the invention has Softness (S) and Formability (F) according to Kawabata, which are closer to cotton knitwear (Ref. 1). Also Drapeability (D) according to Kawabata is closer to cotton knitted comparative material than to the other two experimental materials. Thus, when using an elastomeric laminate, a panty-shaped article is provided having a sensation of imitating clothes that is close to a cotton material. Cowards will also have great comfort and fit to the user's body. When using an elastomeric laminate only in those parts of underpants in which the material properties are used in the best way, a very economical use of the material is achieved.

Preferably, the laminate has a Softness (S) in accordance with Kawabata of at least 20, more preferably at least 30 and most preferably at least 40. It is also preferred that the laminate has formability (F) in accordance with Kawabata not more than 50, preferably not more than 30, more preferably not more than 20 and most preferably not more than 10. It is also preferable that the laminate has drape (D) in accordance with Kawabata not more than 40.

Claims (15)

1. The product (10) in the form of a panty-type lingerie item comprising a front (12), a back (14), a crotch (16) area and a waist area (18), said product (10) having a longitudinal (y) and a transverse (x) a direction, wherein at least a portion of the article (10) contains an elastic laminate (20) formed from the first (22) and second (24) layers of fibrous material and a layer of elastic film (26) located between the first and second fibrous layers (22; 24), characterized in that said laminate (20) has a puncture resistance of at least 15 N . 2. The product according to claim 1, characterized in that the elastic laminate (20) has a puncture resistance of at least 20 N, more preferably at least 30 N. 3. The product according to claim 1, characterized in that at least the front region (12) of the product contains an elastic laminate (20). 4. The product according to claim 1, characterized in that both the front and rear regions (12; 14) of the product contain an elastic laminate (20). 5. The product according to claim 1, characterized in that a substantial part of the crotch area (16) of the product is free of the specified elastic laminate. 6. The product according to claim 1, characterized in that the waist area (18) of the product is free from the specified elastic laminate. 7. The product according to any one of claims 1 to 4, characterized in that the entire product (10) contains an elastic laminate (20). 8. The product according to claim 1, characterized in that said layer of elastic film (26) is breathable. 9. The product according to claim 8, characterized in that said elastic laminate (20) has a Water vapor transmission rate in accordance with Method D of ASTM E96-00 of at least 1,500 g / m ^{2 for} 24 hours, preferably at least , 3000 g / m ² 24 h. 10. The product according to claim 1, characterized in that said elastic laminate (20) has an elasticity in the transverse direction of the product of at least 30%, preferably at least 50%, more preferably 70% when measured in accordance with elasticity test described in the description. 11. The product according to claim 1, characterized in that at least one of the layers of fibrous material (22, 24) has an elongation at maximum load greater than the elasticity of the elastic laminate (20). 12. The product according to claim 1, characterized in that both layers of fibrous material (22, 24) have an elongation at maximum load greater than the elasticity of the elastic laminate (20). 13. The product according to claim 1, characterized in that the layers of fibrous material (22, 24) have an elongation at maximum load of at least 10%, preferably at least 20% greater than the elasticity of the elastic laminate (20 ) 14. The product according to claim 1, characterized in that the first and / or second layers of fibrous material (22, 24) contain a mixture of polymers of polypropylene and polyethylene. 15. The product according to claim 1, characterized in that said elastic laminate (20) contains first and second fibrous layers (22, 24) of spun material, each having a bulk of between 10 and 35 g / m ² , preferably between 12 and 30 g / m ² , more preferably between 15 and 25 g / m ² , and the breathable layer of the elastic film (26) has a bulk of between 20 and 100 g / m ² , preferably between 20 and 60 g / m ² , said elastic the laminate (20) has a Water Vapor Transmission Rate in accordance with Method D of ASTM E96-00 of at least 1500 g / m ² 24 h, preferably about at least 3000 g / m 24 hours

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