DE2546208A1 - ADHESIVE ABSORBENT PRODUCT AND THE METHOD OF MANUFACTURING IT - Google Patents

Description

MÜLLER-BORE · GROENING · DEUFEL · SCHÖN · HERTEJL

PATENTANWÄLTE MUNICH - BKAUNSCHWEIG - COLOGNE ^ O 4 O L UW

DR. W. MÜLUER-eoafe ■ BRAUNSCHWEIG H. W-GROEN'NG. Di ^p L. * iMS - MUNICH OR P. OEUFEL. aiPL.-CHEM. - MUNICH OR. A. YES. DIPU ₁ -CHtM. · MUNICH WERNER HERTEL ₁ DIPL-PHYS, * KOtN

J / P 10-51

Personal Products Company, Milltown, New Jersey, USA

Absorbent product with adhesive fastening and process for its manufacture.

The invention relates to an absorbent product with adhesive attachment or an absorbent product and method to be adhered to the clothing of the user for its manufacture.

The invention thus relates to absorbent products of the type sanitary napkins or sanitary napkins and in particular those products that are adhesively attached to the user's clothing,

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to protect clothing.

To have such adhesively attached absorbent products have recently proven extremely successful commercially and are particularly convenient during those preceding the women's menstrual cycle and the end of the menstrual cycle Days to use. Such products can also be found in tampons women using it as additional protection on days when particularly heavy bleeding is to be expected. Farther such products are also used by women between menstrual periods and during medication treatment to protect the underwear against body discharge. These products are particularly convenient as they do not require any needles, Belts or special undergarments require and are simply held in place by being held in place with the adhesive Side on the underwear.

The absorbent products of this type usually comprise an absorbent core or pad which consists entirely of short cellulose fibers, such as cotton linters or wood pulp fibers (wood pulp fibers) or mixtures thereof, which are held together predominantly by inter-fiber bonds and which are commonly referred to as "wadding" or "fluff" will. Such cores are generally rectangular in shape, both in plan view and in cross-section, and of a soft liquid-permeable or fluid-permeable shell or cover layer, for example one with holes or surrounded Apertured nonwoven fabric such as that described in U.S. Patents 2,862,251, 3,081,514, and 3,081,515. On the side facing away from the body of the user usually a thin, liquid-impermeable or fluid-impermeable Barrier layer made of a material such as polyethylene. This layer is usually made by gluing with it connected to the rest of the absorbent product and attached to the outer surface with a strip of self-adhesive or self-adhesive adhesive with which the product is attached to a '

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Garment, such as a pair of panties, is attached. On the strip of self-adhesive there is a peelable Protective strip arranged, which is peeled off immediately before using the product. The ones described above The cover layers or covers and barriers used in absorbent products are generally longer than the absorbent Core to place the core inside the product and tabs on opposite ends of the Form product.

One of the problems encountered in the past is proper control of the amount of glue used to attach the barrier layer to the product, as using too much adhesive will cause the product to fall into place undesirably becomes stiff, especially in the area of the end strips, and the absorbent product changes during use If the amount of adhesive is too small, it can peel off with a certain amount of stress.

Another annoying problem that occurs when using the products described above is caused by the fact that the barrier used to contain body fluids in the product is extremely thin and flexible. As a result, it is possible that when the protective strip torn off the self-adhesive adhesive and the user is not extremely careful with different areas of the self-adhesive glue together so that the barrier layer becomes wrinkled or wrinkled and the product often cannot be used. The problem is compounded by the fact that the exposed pressure sensitive adhesive must adhere well to the garment of the user, so due to this necessity the pressure sensitive adhesive must be extremely sticky. Thus, as a result of it Different areas of the self-adhesive adhesive that have been stuck together are extremely difficult to separate again from one another. If this occurs during use, for example as a result of the constant loads that the product is subjected to

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Is subject to use, these self-adhesive areas are no longer in place to fix the product available so that the product can shift.

The invention now brings a solution to the above problems by applying a unique pattern in which the adhesive is applied, which secures the barrier layer to the rest of the absorbent product. This glue pattern comprises a continuous strip of adhesive extending from one end of the barrier layer extends to the other end of the barrier layer and on that with respect to the self-adhesive Adhesive layer arranged opposite side of the barrier layer and just as the layer of pressure sensitive adhesive is aligned. This adhesive strip gives the Barrier layer in the transverse direction has considerable strength. The adhesive strip comprises one generally rectangular shaped central region which extends over most of the length of the barrier layer and which is preferably slightly is wider than the strip of pressure sensitive adhesive, although this is not critical to the invention.

The subject of the invention is therefore an absorbent product to be attached to the clothing of the user by gluing, that is characterized by

an absorbent core or pad with longitudinal sides and transverse ends, a first generally rectangular, the body of the user facing surface and a second, generally rectangular, the clothing of the user facing surface;

a liquid-permeable or fluid-permeable cover layer adjacent to the first surface and which is generally rectangular and is longer and wider than the core and its opposite longitudinal edges around the adjacent longitudinal edges of the Core folded around and extending inwardly across the second surface of the core;

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a liquid-impermeable or flux-impermeable barrier layer, which covers the inwardly extending part of the cover layer and is generally as long as the Top layer;

a layer of a self-adhesive or self-adhesive adhesive that extends lengthways on the outside of the Barrier layer extends;

a peelable protective strip covering the layer of pressure sensitive adhesive; and

an adhesive layer disposed on the inside of the barrier layer and used to attach the barrier layer to the product in the form of a plurality of lines running lengthwise to the barrier layer and parallel to the side edges of the Core run, and an adhesive strip, which is placed under the layer of the pressure-sensitive adhesive, like this one aligned and at least as wide as the self-adhesive layer.

Thus, the absorbent product according to the invention has one side has a liquid-impermeable barrier layer adhered to an absorbent core by adhesive bonding, wherein the core is at least partially surrounded by a liquid-permeable cover layer or shell, which against the Body of the user is to be carried. The barrier layer is provided with a central strip of self-adhesive adhesive, with which the absorbent product can be attached to an item of clothing. The pressure sensitive adhesive is covered with a removable protective strip. The barrier layer is made with the help of a multitude of parallel arranged adhesives lines or strips of glue left on the surface of the Barrier layer are applied, which is opposite to the surface carrying the pressure-sensitive adhesive layer, attached. This surface also includes a strip of adhesive that aligned with the strip of self-adhesive or in the same way as it is arranged, and which serves to reinforce the central area of the product and which prevents that different areas of the strip from the self-adhesive

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Glue adhesive together in an undesirable manner after the protective strip has been peeled off. The adhesive strip covers a rectangular area generally as long as the absorbent core and a multitude of lines of adhesive, extending outward from the opposite ends of the generally rectangular area into the tab areas extend. These lines of glue are spaced apart from one another, which is generally the same is like the distance between the glue lines that run outside the glue strip.

Thus, the adhesive pattern of the present invention includes a plurality of spaced apart, continuous and parallel lines of glue, which are on the opposite Sides of the adhesive strip run and extend the full length of the barrier layer and serve to hold together with the adhesive strip the barrier layer on the one below To attach the area of the absorbent product. The adhesive strip also has a plurality of spaced apart spaced lines extending outward from opposite ends of the rectangular shaped area extend and which have about the same distance from one another as those running on both sides of the strip Lines.

The generally rectangular area of the adhesive strip corresponds in length to the length of the core of the absorbent product, with that of the opposite ends of the Adhesive lines emanating from the strip extend into the tab area or strip area of the product. Consequently runs a continuous in the adhesive pattern described above Adhesive strips from one end of the barrier layer to its other end, being compared to the rest Product a lesser amount of the adhesive in the tab area is available.

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During the manufacture of the absorbent product, the the end. the core and the liquid-permeable cover layer of the product with the one described above Adhesive pattern-bearing barrier layer matched, whereupon the entire structure in the areas outside the absorbent core is compressed so that the Adhesive present on the barrier layer spreads slightly into the tab area and the barrier layer firmly adheres to the Top layer of the product connects. By applying the spaced apart from the stiffening rectangular area of the continuous adhesive strip outside extending adhesive lines is not only used for Making the product necessary amount of glue on one It is kept to a minimum, but also provides an effective tab seal without the tabs becoming stiff. Due to the lower The amount of glue in the area of the tabs (compared to the generally rectangular area of the strip) will also do that Penetration of the adhesive substance during pressing prevents the processing equipment from fouling and preventing efficient high-speed production could.

The continuous central strip of the adhesive pattern can be applied simultaneously with the application of the Adhesive lines or applied in a separate treatment stage will. In either case, the strip is preferably formed by using a suitable adhesive substance through openings of a metering valve on the barrier layer and controls the valve in such a way that the adhesive substance in the area of the barrier layer, which is in the immediate vicinity of the metering valve, during the formation of the accumulates or converges in the generally rectangular area of the strip and in those areas of the strip, corresponding to the tab areas of the product, beyond the generally rectangular area, discrete adhesive forms lines. The training of the lines beyond the

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Ends of the generally rectangular area is substantially equal to that of the lines running along the opposite sides of the rectangular area, so that the strength the tab seal is generally uniform across the width of the product.

Further embodiments, objects and advantages of the invention emerge from the following description and the drawing.

The drawing shows:

In Fig. 1 is a perspective view of an absorbent product according to the invention, with certain areas of the Product is folded back or removed to reveal underlying areas;

Figure 2 is a plan view of the lower surface of the barrier layer of the absorbent product of the invention;

FIG. 3 is a sectional view taken along line 3-3 of FIG. 1;

FIG. 4 is a sectional view taken along line 4-4 of FIG. 1;

5 is a bottom plan view of a metering valve used to form the central adhesive strip on the lower Surface of the barrier layer can be used; and

in Fig. 6 is a sectional view taken along the line 6-6 of Fig. 5. ·

Although the invention includes many different embodiments, the drawing shows a particularly preferred embodiment shown, on the basis of which the invention will be explained in more detail below, for example.

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The absorbent product 10 shown in FIG. 1 comprises an absorbent core or pad 12, a liquid pervious pelvic layer 14, and a liquid-impermeable barrier layer 1S- The absorbent Core 12 consists entirely of slightly compressed short ones Cellulose fiber] *, that is, fibers with a length of less than about 6 mm C1 / 4 inch), and is preferably in the form of a Low density wadding, commonly referred to as "wadding" or "fluff", wherein the fibers are without the use an added adhesive through interfiber bonds be held together. The core 12 can be made from wood pulp fibers (Wood pulp fibers} or cotton linters or mixtures consist of it «The core 12 is generally in the shape of a rectangular parallelepiped, as can be seen from the comparison 1 and 3 can be seen.

A wide variety of fabrics can be used for the cover layer 14, provided that they are soft, dimensionally stable and permeable to body fluids. The apertured or perforated nonwovens of the type described in the above-mentioned patents have proven particularly beneficial for the invention. The cover layer 14 is rectangular in shape and is wider and longer than the core 12. The lateral longitudinal edges 14a and 14b (see FIGS. 3 and 4) of the cover layer or the shell are trimmed around the opposite longitudinal edges of the core and appear on the outer side of the Product _e, that is, the side of the product facing away from the user's body which will be connected to an undergarment, as will be explained below, although the cover sheet portions 14a and 14b are shown as being spaced from one another According to the invention, a wider cover layer can also be used, so that the side edges of the cover layer come closer to one another or even overlap when they are folded over.

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The barrier layer: 16 consists of a thin, liquid-impermeable layer Film or pollen material, such as polyethylene, and is also rectangular in shape and corresponds in length to cover layer 14 and in width approximately to core 12. According to the invention has a polyethylene film with a Thickness of Q, Q51 mm (2 mils) proved to be a suitable barrier. On the outside of the barrier layer 16, a strip 18 is made A tacky, pressure-sensitive adhesive is applied that extends continuously from one end of the barrier to the other End extends. The strip 18 of the pressure-sensitive adhesive covers a rectangular area that runs "in the middle." the exposed side of the barrier layer 16 is arranged. on The adhesive strip 18 is a peelable protective strip 20 arranged, which protects the adhesive strips 18 before using the product. The protective strelfen 2O can be slightly wider be than the adhesive strip 18. The strip 18 from the self-adhesive adhesive can be applied directly to the barrier layer, applied to the protective strip 2O and transferred with this to the barrier layer (as for example in the OS-PS 3 595 237 is described) or can in the form of a bilateral adhesive adhesive strip are provided, the A person skilled in the art can easily find the most favorable embodiment in each case can choose. In all cases, after removing the Protective strip 2O of the adhesive strip 18 an exposed, sticky mass that is used to attach the product to the user's clothing, but without the barrier adhesive system according to the invention, take particular care would require the user to be affected by the self-adhesive properties to report problems posed by this layer.

According to the invention are on the lower surface, the interior Surface or the inside 22 of the barrier layer 16 an in uninterrupted adhesive strip 24 arranged in the middle, the strip 18, like the adhesive, is aligned or is in alignment therewith, and a plurality of spaced apart arranged, parallel lines of adhesive 26, which are outside the opposite rare of the strip 24 run, arranged.

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As can be seen from Figure 2, the adhesive extends lines 26 without interruption from one end of the barrier to its other end (being the length of the barrier in Fig. 2 by the dashed lines) and are parallel to the barrier layer and the Adhesive strips 24 arranged. The strip 24 includes a generally rectangular shaped central region 28 which extends extending over most of the length of the barrier, and a plurality of equidistantly spaced from one another parallel lines 28a extending outwardly from each end of the rectangular area 28. The rectangular area 28 corresponds in length generally the core 12, while the lines 28a extend beyond the core 12 so that they are also present in the tabs 30 at opposite ends of the product. The distance between lines 28a is generally the same as the distance between lines 26, the amount of glue per unit length for all Lines is essentially the same, so that the strength of the tab seal is across its entire width is even.

The strip 24 can be formed simultaneously with the formation of the lines 26 or in a separate operation. One can use similar or different adhesives for this. 5 and 6, a metering valve 32 is shown which is used for the production of the strip 24 can be used and the desired adhesive pattern by a wiping action on a The endless tape of the barrier material is deposited by bringing this material into contact with the lower surface of the Valve 32 passes under this.

The valve 32 comprises a valve body 34 with a chamber 36 which narrows downward, as can be seen from FIG. A suitable adhesive substance is applied under pressure over the Inlet 38 is introduced into chamber 36 and passed downward from chamber 36 via outlet ports 40, for each line 28a such an outlet opening is provided.

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The lower end of the valve body 34 has an undercut 42 which forms a space in which the from the openings 40 leaking adhesive collects. In the valve body 34 a vertically movable control slide 44 is arranged with which the The amount of adhesive flowing through the openings 40 is controlled. The lower end 4 6 of the control slide corresponds in its conical shape to the narrowing lower region of the chamber When the lines 28a are formed on the sheet of barrier material passing directly beneath the valve 32 is, the control slide 44 is moved downwards so that the lower end 4 6 closes the openings 40, so that the Adhesive flows directly from the openings 40 onto the barrier layer film. When the rectangular areas 28 on the barrier film are to be formed, the control slide 44 is moved upwards and releases the openings 40, so that the adhesive is pressed outward under pressure and fills the space formed by the undercut 4 2, so that the area 28 both is completely covered with adhesive in the longitudinal direction as well as in the transverse direction.

The exact position of the spool in relation to the valve chamber during the formation of the strip 24 depends on many factors, namely whether a cold adhesive or a hot melt adhesive is used, the viscosity of the adhesive used, the speed of movement of the barrier film, etc. Furthermore, the structure of the metering valve is not according to the invention critical and other means other than those shown in Figures 5 and 6 may be used.

During the manufacture of the absorbent product, partial components consisting of spaced apart cores 12 which are partially enveloped by the cover layer 14, correct in time with respect to the reciprocating movement of the control slide 44 dem with the adhesive covered spray coat material supplied so that the lines 28a with those areas of the cover layer between the Cores match.

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The sandwich structure is then formed between pressure rollers compressed under low pressure to prevent the penetration of the Adhesive lines 26 and the adhesive strip 24 in the underlying Fiber area of the product and thus to effect a connection.

As can be seen from FIGS. 3 and 4, the barrier layer is 16 over two groups of two adhesive lines 26 each with each of the inwardly folded edges 14a and 14b of the cover sheet 14 connected, while two groups of four adhesive lines 26 each connect the barrier layer 16 on both sides of the adhesive strip 24 to the core 12 while there are four lines of glue 28a at the ends of the strip 24 in the tab areas 30. According to a preferred embodiment of the invention wherein the barrier layer is 44.5 mm (1 3/3 inch) wide, glue lines 26 and 28a approximately in width 1.19 mm (3/64 inch) and a rectangular area 28 about 9.53 mm (3/8 inch) wide was used. The entire adhesive pattern on the barrier layer is about 0.10 mm (0.004 inches) thick and provides a strong bond between the barrier layer and the rest of the absorbent product. Due to the presence in the tab areas of the product, Adhesive lines 28a arranged at a distance from one another becomes a Undesirable stiffness of the tabs, which occurs when there is a continuous layer of adhesive such as the strip, is prevented 24, is provided. Furthermore, the smaller amount of adhesive in the tab areas means that the adhesive strikes through during the pressing necessary in the manufacture of the product and thus soiling of the manufacturing device avoided.

The rectangular area 28 of the strip 24 is preferably at least as wide as the strip 18 of the self-adhesive Adhesive, wherein in the embodiment described in the preceding paragraph, the strip from the self-adhesive Glue a width of 6.35 mm (1/4 inch) and the rectangular one

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Area is 3/8 inch (9.53 mm) wide. It has It has been shown that this area is the center of the barrier layer protects and provides increased protection against creasing or wrinkling of the barrier layer, so that the likelihood is diminished that part of the self-adhesive The adhesive inadvertently touches another area of the After the protective strip is peeled off.

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Claims (12)

Claims Anything to be attached to the clothing of the user, absorbent product characterized by an absorbent core (12) having longitudinal sides and transverse ends, a first, generally rectangular, the body of the User-facing surface and a second, generally rectangular, the clothing of the user facing Area; a liquid pervious cover sheet (14) adjacent the first surface which is generally rectangular and is longer and wider than the core (12) and theirs opposing longitudinal edges (14a, 14b) are folded around the adjacent longitudinal edges of the core (12) and after extending inwardly over the second surface of the core (12); a liquid impermeable barrier layer (16), which the inwardly extending part (14a, 14b) of the cover layer (14) covered and generally as long as the cover layer (14); a layer (18) of pressure sensitive adhesive extending longitudinally on the outside of the barrier layer (16) extends; a peelable protective strip (20) covering the layer (18) of the pressure-sensitive adhesive; and one used to attach the barrier layer (16) to the product, on the inside (22) of the barrier layer arranged adhesive layer in the form of a plurality of lines (26), which in Longitudinal direction to the barrier layer (16) and parallel to the Side edges of the core (12) run, and an adhesive strip (24), which is arranged under the layer (18) of the self-adhesive adhesive, like, this, aligned and is at least as wide as the layer of the pressure-sensitive adhesive. 609817/0425 2. Product according to claim 1, characterized z eichnet that the layer (18) from the self-adhesive Glue and the glue strip (24) in the middle of the Barrier layer (16) are arranged. 3. Product according to claim 1, characterized in that that the adhesive strip (24) is an uninterrupted, generally rectangular shaped area the barrier layer, which is generally as long as the core (12). 4. Product according to claim 3, characterized in that from both ends of the adhesive strip (24) spaced apart adhesive lines (28a) extend outward. 5. Absorbent product with an inner side to be worn against the body of the user and an opposite side Exterior characterized by an absorbent core (12); a liquid-permeable one adjoining the inside of the core (12) Cover layer (14), the opposite side edges (14a, 14b) of which over the adjacent side edges of the Cores (12) are folded over and extend inwardly over the outside of the product; one over the inwardly extending areas (14a, 14b) lying, liquid-impermeable barrier layer which is generally as long as the cover layer (14); a layer (18) of pressure sensitive adhesive on the outside of the barrier layer (16) for securing the product on underwear or the like; and one for attaching the barrier layer (16) to the outside adhesive layer in the form of a plurality of adhesive layers serving the product and arranged on the inside (22) of the barrier layer of adhesive lines (26) arranged at a distance from one another in the transverse direction, which extend in the longitudinal direction to the barrier 60981 7/0425 layer (16) and extend parallel to the side edges of the core (12), and an adhesive strip (24), which also how the layer (18) of the self-adhesive adhesive is arranged and applied in alignment with this, the Adhesive strip (24) is at least twice as wide as the glue lines (26). 6. Product according to claim 5, characterized in that that the adhesive strip (24) a uninterrupted, generally rectangular shaped area of the barrier layer (16), the area in is generally as long as the core (12). 7. Product according to claim 6, characterized z eic hnet that from the ends of the continuous, generally rectangular shaped adhesive strip (24) spaced adhesive lines (28a) extend outward. 8. A process for the manufacture of an absorbent product, characterized in that one forms a liquid-impermeable barrier layer which is covered on one side with a layer of a pressure-sensitive adhesive is provided; on the opposite side of the barrier layer from the side provided with the layer of pressure-sensitive adhesive applying an adhesive substance by (a) one likewise like the layer of pressure sensitive adhesive, and (b) a plurality of spaced apart adhesive strips applying lines of adhesive located adjacent opposite edges of the strip; and an absorbent material attached to the adhesive substance. 609817/0425 9. The method according to claim 8, characterized in that when applying the adhesive strip applying the adhesive substance on a continuous, generally rectangular shaped area, of its opposite ends spaced lines from the adhesive substance move in the longitudinal direction extend outside; and the attachment of the absorbent material is effected by attaching the absorbent material the continuous, generally rectangular shaped strip of adhesive; and the outwardly extending adhesive lines attached. 10. A process for the manufacture of an absorbent product, characterized in that one forms a liquid impervious barrier layer; an adhesive substance in on one side of the barrier layer Form of a strip of adhesive and a plurality of spaced apart along the side edges of the Stripes running lines applies; and an absorbent material on the adhesive substance attached. 11. Process for the manufacture of an absorbent product from first and second components, characterized in that one has an adhesive substance applying one side of a first component by using a strip of adhesive and a plurality of spaced apart, applying lines of glue extending outside the longitudinal edges of the strip; and the second component is attached to the adhesive substance. 12. The method according to claim 11, characterized in that that a liquid-impermeable barrier layer is used as the first component. 609817/0425 Blank page