Laminate and wound covering material

Abstract

To provide a laminate having excellent performance capable of being preferably used as a wound covering material.SOLUTION: One form of the present invention comprises a substrate and a foam layer directly laminated onto one surface of the substrate, where the material of the substrate is thermoplastic polyurethane, and the foam layer is polyurethane foam. The water absorption of the polyurethane foam measured by the following measurement method is 10 g / g or more. (Measurement Method) Measurement is conducted on the basis of BS EN 13726-1. A test piece of 50 mm×50 mm×t5 mm is prepared. The mass of the test piece before immersion is measured. The test piece is immersed in a test liquid at 40 times its mass at 37°C for 30 minutes. After hanging the immersed test piece for 20 seconds, the mass is measured. The water absorption is calculated according to the following formula. Water absorption=[(mass after immersion-mass before immersion) / mass before immersion]SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a laminate and a wound dressing material.

Background Art

[0002] Various materials are used as wound dressing materials.

[0003] In recent years, polyurethane foam and hydrocolloid may be used as wound dressing materials. By using such a wound dressing material, it is expected to have the effect of shortening the time to healing by appropriately retaining the exudate from the body and preventing drying.

[0004] For example, Patent Document 1 discloses using, as a wound dressing material, a foam obtained by reacting a low molecular weight diisocyanate having a molar mass of A1) 140 to 278 g / mol, a polyalkylene oxide having an OH functionality of 2 or more, and A3) optionally an additional isocyanate-reactive component not corresponding to A2).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, the polyurethane foam according to Patent Document 1 may not have sufficient performance as a wound dressing material.

[0007] Therefore, an object of the present invention is to provide a laminate having excellent performance that can be preferably used as a wound dressing material, and a wound dressing material including the laminate.

Means for Solving the Problems

[0008] The inventors of the present invention have conducted intensive studies and found that the above problems can be solved by using a polyurethane foam having specific properties. That is, the present invention is as follows.

[0009] One form of the present invention is a laminate having a substrate and a foam layer directly laminated on one surface of the substrate. The material of the substrate is thermoplastic polyurethane, The foam layer is a polyurethane foam, The water absorption of the polyurethane foam measured by the following measurement method is 10 g / g or more. (Measurement method) Measure according to BS EN 13726-1. Prepare a test piece of 50 mm × 50 mm × t 5 mm. Measure the mass of the test piece before immersion. Immerse the test piece in an evaluation liquid having a mass 40 times the measured mass at 37°C for 30 minutes. After hanging the immersed test piece for 20 seconds, measure the mass. Calculate the water absorption according to the following formula. Water absorption = [(mass after immersion - mass before immersion) / mass before immersion]

[0010] It is preferable that the contact angle of the substrate measured by the following measurement method is 40° or less for the laminate. (Measurement method) Prepare a urethane prepolymer contained in the foam composition which is the raw material of the foam layer as the liquid for measuring the contact angle. Install the microscope horizontally and focus it. Next, drop the urethane prepolymer droplet onto the substrate with a syringe. Measure the contact angle from the image taken with the microscope 15 seconds after dropping. Measure the contact angle at three locations on the substrate, calculate the average value, and use it as the contact angle.

[0011] It is preferable that the peel strength measured by the following measurement method is 0.8 N / 24 mm or more for the laminate. (Measurement method) Attach a first double-sided tape to the foam layer surface of the laminate and mold it into a width of 24 mm and a length of 11 mm. Attach a PET film to the base material surface of the laminate via a second double-sided tape. Cure at 60 °C for 90 minutes. Attach the first double-sided tape to a SUS plate. Move a 2 kg roller back and forth on the foam layer for 5 seconds each to obtain a measurement sample. Immerse the measurement sample in ion-exchanged water at 37 °C for 1 hour. Lift the measurement sample out of the ion-exchanged water. Wipe off the moisture on the surface of the measurement sample and perform 90° peeling with an autograph (1 kN) to measure the peel strength.

[0012] Another form of the present invention is a wound dressing material comprising the laminate.

Advantages of the Invention

[0013] According to the present invention, it is possible to provide a laminate having excellent performance that can be preferably used as a wound dressing material, and a wound dressing material comprising the laminate.

Brief Description of the Drawings

[0014]

Figure 1

Embodiments for Carrying Out the Invention

[0015] In this specification, when an upper limit value and a lower limit value are separately described, a numerical range combining any upper limit value and any lower limit value is considered to be substantially disclosed.

[0016] In this specification, the content of a certain component in the polyurethane foam can be read as the content of the certain component in the raw material composition (foam composition) based on the solid content of the raw material composition (foam composition).

[0017] In this specification, when a certain compound is described, its isomers are also considered to be described simultaneously.

[0018] In this specification, unless otherwise specified, all kinds of measurements are carried out at an environmental temperature of room temperature (25°C).

[0019] In this specification, the evaluation liquid refers to a solution obtained by diluting 8.4 g of sodium chloride and 0.4 g of potassium chloride with distilled water to make 1 L of the solution.

[0020] Hereinafter, the structure, manufacturing method, physical properties / characteristics, uses, etc. of the laminate will be described, but the present invention is not limited thereto.

[0021] <<<Structure>>> FIG. 1 is a conceptual side view of a laminate 10 according to the present disclosure. As shown in FIG. 1, the laminate 100 has a base material 10 and a foam layer 20 directly laminated on one surface (one main surface) of the base material 10.

[0022] The laminate may have layers other than the base material and the foam layer (other layers). Examples of the other layers include a protective layer (release film, etc.), a printing layer, an adhesive layer, etc.

[0023] In FIG. 1, although a laminate in which the width and length of the base material 10 and the width and length of the foam layer 20 are the same is disclosed, the width and length of the base material 10 may be made larger than the width and length of the foam layer 20, and a region where the foam layer 20 is not provided may be provided on the base material 10. Further, an adhesive layer may be provided in the region where the foam layer 20 is not provided.

[0024] Hereinafter, the base material and the foam layer constituting the laminate will be described.

[0025] <<Base material>> The material of the base material is preferably thermoplastic polyurethane. By using thermoplastic polyurethane as the base material, it becomes easy to obtain a laminate excellent in texture and water vapor permeability.

[0026] As the thermoplastic polyurethane, conventionally known ones can be used, and the specific types (monomers) can be appropriately changed according to the uses, etc.

[0027] Thermoplastic polyurethane is a reaction product of a polyol and a polyisocyanate. Examples of the polyol include polyester polyol, polycarbonate polyol, polyether polyol, etc. Examples of the polyisocyanate include aromatic polyisocyanate, aliphatic polyisocyanate, etc. As the polyol and polyisocyanate, components exemplified as raw materials for polyurethane foam described later may be used.

[0028] As the base material, commercially available products or the like may be used according to the application.

[0029] The base material is preferably in the form of a film. By forming the base material into a film, it is possible to prevent leakage when the foam comes into contact with a liquid (such as a bio-derived liquid or a chemical solution), and it is also easy to apply the foam composition in the coating process and subsequent processes, and a homogeneous foam layer is easily formed. In terms of simply supporting the foam layer, the base material may be in the form of a non-woven fabric, a woven fabric, or the like.

[0030] The thickness of the base material can be appropriately changed according to the application and the like. From the viewpoint of texture and the like, it is preferably 0.005 mm or more, or preferably 0.010 mm or more, and it is preferably 0.100 mm or less, or preferably 0.050 mm or less.

[0031] The contact angle of the base material (urethane prepolymer contact angle) measured by the following measurement method is preferably 40° or less, more preferably 38° or less, still more preferably 37° or less, and particularly preferably 35° or less.

[0032] (Measurement method of contact angle) The contact angle is measured using a microscope. As the object for measuring the contact angle, a urethane prepolymer contained in the foam composition, which is the raw material of the foam layer, is prepared. The microscope is installed horizontally and focused. Next, a droplet of the urethane prepolymer is dropped onto the substrate with a syringe. The contact angle is measured from an image taken with the microscope 15 seconds after the droplet is dropped. The contact angle is measured at three locations on the substrate, and the average value is calculated and taken as the contact angle.

[0033] The contact angle of the substrate can be adjusted by changing the material of the substrate (for example, the combination of polyol and polyisocyanate).

[0034] <<Foam layer>> The foam layer is preferably a polyurethane foam. By making the foam layer a polyurethane foam, it is easy to obtain a laminate excellent in the retention of liquids (exudates and chemical solutions) and texture.

[0035] Also, from the viewpoint of increasing the peel strength and the like, it is preferable that the foam layer is directly laminated on the substrate.

[0036] By using a thermoplastic polyurethane as the substrate, a polyurethane foam as the foam layer, and forming a structure in which the foam layer is directly laminated on the substrate, it becomes easy to obtain a laminate particularly excellent in peel strength and the like.

[0037] The polyurethane foam is usually obtained by foaming and curing a foam composition containing a urethane prepolymer. Also, the polyurethane foam may contain other components. Hereinafter, an example of the urethane prepolymer, which is a constituent raw material of the polyurethane foam, and other components will be described.

[0038] A urethane prepolymer is obtained by reacting a polyol with a polyisocyanate. In other words, a urethane prepolymer is a reaction product of a polyol and a polyisocyanate. More specifically, a urethane prepolymer is usually an isocyanate group-terminated urethane prepolymer (isocyanate prepolymer) obtained by subjecting a polyol and a polyisocyanate to a urethane reaction such that the polyisocyanate is in excess.

[0039] The polyol is not particularly limited and can be freely selected in consideration of the properties of the desired polyurethane foam.

[0040] Examples of the polyol include polyester polyol, polycarbonate polyol, polyether polyol, polyester ether polyol, etc., and can be freely selected in consideration of the properties of the desired polyurethane foam.

[0041] Examples of the polyester polyol include those obtained by dehydration condensation reaction of aliphatic dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, and azelaic acid, aromatic dicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, and naphthalene dicarboxylic acid, alicyclic dicarboxylic acids such as hexahydrophthalic acid, hexahydroterephthalic acid, and hexahydroisophthalic acid, or acid esters or acid anhydrides thereof, and ethylene glycol, 1,3-propylene glycol, 1,2-propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, 1,8-octanediol, 1,9-nonanediol, etc., or mixtures thereof; and polyester polyols such as polypropylene glycol obtained by ring-opening polymerization of lactone monomers such as ε-caprolactone and methylvalerolactone, and polylactone diol.

[0042] Examples of the polycarbonate polyol include those obtained by reacting at least one polyhydric alcohol such as ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, 1,8-octanediol, 1,9-nonanediol, diethylene glycol, etc. with diethylene carbonate, dimethyl carbonate, diethyl carbonate, etc.

[0043] Examples of the polyether polyol include polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc. obtained by polymerizing cyclic ethers such as ethylene oxide (EO), propylene oxide, tetrahydrofuran, etc. respectively, and copolymers thereof. Further, they can also be obtained by polymerizing the above cyclic ethers using polyhydric alcohols such as glycerin and trimethylolethane.

[0044] The polyol can be used alone or in combination of a plurality.

[0045] The polyol is preferably a diol and / or a triol.

[0046] The polyol preferably contains a random type polyether polyol. More specifically, it is preferable that the random type polyether polyol is contained in an amount of 50% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more, or 90% by mass or more based on the total polyol constituting the urethane prepolymer.

[0047] Random polyether polyols contain ethylene oxide. Here, the "random type" of random polyether polyols indicates that they are random copolymers. That is, random polyether polyols refer to polyether polyols in which ethylene oxide and propylene oxide are randomly copolymerized. Note that polyether polyols in which ethylene oxide and propylene oxide are block copolymerized are referred to as block polyether polyols.

[0048] Random polyether polyols preferably have a proportion of ethylene oxide in one molecule of random polyether polyols (hereinafter sometimes referred to as the EO content of random polyether polyols) of 20.0% by mass or more, 25.0% by mass or more, or 30.0% by mass or more. By including random polyether polyols with an EO content in such a range as the polyol, it becomes easier to adjust the EO content of the urethane prepolymer, and a polyurethane foam with excellent hydrophilicity can be obtained.

[0049] Random polyether polyols preferably contain diol compounds and triol compounds.

[0050] The number average molecular weight of the polyol is preferably 200 to 5000, 300 to 4500, or 400 to 4000. In particular, when the number average molecular weight of the random polyether polyol is in such a range, the number average molecular weight of the urethane prepolymer is included in an appropriate range, so a polyurethane foam having excellent water absorption and the like can be obtained.

[0051] Note that the raw materials of the urethane prepolymer may contain a monoalcohol other than the polyol as an alcohol component as long as the effects of the invention are not inhibited.

[0052] The polyisocyanate is not particularly limited and can be freely selected in consideration of the properties of the desired polyurethane foam.

[0053] The polyisocyanate may be bifunctional or trifunctional or higher functional.

[0054] Examples of the bifunctional polyisocyanate include aromatic ones such as 2,4-toluene diisocyanate (2,4-TDI), 2,6-toluene diisocyanate (2,6-TDI), m-phenylene diisocyanate, p-phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate (4,4'-MDI), 2,4'-diphenylmethane diisocyanate (2,4'-MDI), 2,2'-diphenylmethane diisocyanate (2,2'-MDI), hydrogenated MDI, xylylene diisocyanate, 3,3'-dimethyl-4,4'-biphenylene diisocyanate, 3,3'-dimethoxy-4,4'-biphenylene diisocyanate, polymethylene polyphenyl polyisocyanate, 1,5-naphthalene diisocyanate, xylylene diisocyanate (XDI), hydrogenated XDI, tetramethylxylylene diisocyanate (TMXDI), etc. alicyclic ones such as cyclohexane-1,4-diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, methylcyclohexane diisocyanate, etc. alkylene ones such as butane-1,4-diisocyanate, hexamethylene diisocyanate, isopropylene diisocyanate, methylene diisocyanate, lysine diisocyanate, etc.

[0055] Examples of polyisocyanates having three or more functional groups include 1-methylbenzene-2,4,6-triisocyanate, 1,3,5-trimethylbenzene-2,4,6-triisocyanate, biphenyl-2,4,4'-triisocyanate, diphenylmethane-2,4,4'-triisocyanate, methyldiphenylmethane-4,6,4'-triisocyanate, 4,4'-dimethyldiphenylmethane-2,2',5,5'-tetraisocyanate, triphenylmethane-4,4',4''-triisocyanate, polymeric MDI, lysine ester triisocyanate, 1,3,6-hexamethylene triisocyanate, 1,6,11-undecane triisocyanate, bicycloheptane triisocyanate, 1,8-diisocyanatomethyloctane, and the like.

[0056] In addition, the polyisocyanate can include these modified products, derivatives, and the like.

[0057] The polyisocyanate can be used alone or in combination of two or more.

[0058] The polyisocyanate preferably contains an aliphatic isocyanate. More specifically, it is preferable that the aliphatic isocyanate accounts for 50% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more, or 90% by mass or more of the total polyisocyanates constituting the urethane prepolymer.

[0059] The blending amount of the polyisocyanate can be adjusted so that the average functional group number of the hydroxyl groups of the polyol and the NCO% of the urethane prepolymer are within a desired range. For example, when the total blending amount of the polyol and the polyisocyanate is 100% by mass, the blending amount of the polyisocyanate can be 10 - 40% by mass or 20 - 35% by mass.

[0060] Other components include resin components other than urethane prepolymers and known additives. Examples of known additives include catalysts, surfactants, antioxidants, ultraviolet absorbers, antibacterial agents, and the like. Further, the polyurethane foam may contain additives (for example, foam stabilizers described later) used in the production of the polyurethane foam.

[0061] Other components can be 10% by mass or less, 5% by mass or less, or 2% by mass or less, etc., based on the total amount of the polyurethane foam.

[0062] The average functionality number (isocyanate group number) of the urethane prepolymer is usually 2 or more, preferably more than 2 and less than 3, or 2.2 or more and 2.7 or less.

[0063] The NCO% (isocyanate content) of the urethane prepolymer is preferably 3.0 - 10.0% or 4.0 - 10.0%. By setting the NCO% of the urethane prepolymer within such a range, when the polyurethane foam is made hydrophilic, it is possible to obtain a polyurethane foam with excellent balance in water absorption rate, water absorption amount, etc.

[0064] The NCO% of the urethane prepolymer is measured in accordance with Method A (toluene / dibutylamine, hydrochloric acid method) of JIS K1603-1:2007 "Plastics - Polyurethane Raw Materials - Aromatic Isocyanates - Test Methods - Part 1: Method for Determination of Isocyanate Group Content".

[0065] The viscosity of the urethane prepolymer at 25°C is preferably 1000 - 10000 mPa·s, 2000 - 8000 mPa·s, or 3000 - 6000 mPa·s. By setting it within such a range, a polyurethane foam having excellent performance can be easily obtained.

[0066] The viscosity of the urethane prepolymer can be changed, for example, by adjusting the molecular weight, average functionality number, etc. of the urethane prepolymer.

[0067] The number average molecular weight of the urethane prepolymer is not particularly limited as long as the effects of the invention are not inhibited. For example, it is preferably 500 to 10,000, 750 to 7,500, or 1,000 to 5,000. By setting it within such a range, the viscosity of the foam composition containing the urethane prepolymer does not become too high, making molding easy, and a polyurethane foam having excellent water absorption and the like can be obtained.

[0068] The viscosity of the urethane prepolymer at 25 °C is the E-type viscosity measured in accordance with JIS Z8803:2011 "Method for Measuring Viscosity of Liquids". The measurement is performed using a cone-plate rotational viscometer.

[0069] The proportion of alkylene oxide in one molecule of the urethane prepolymer is preferably 20.0 to 55.0% by mass, 25.0 to 55.0% by mass, or 30.00 to 52.5% by mass. More specifically, the proportion of ethylene oxide in one molecule of the urethane prepolymer (hereinafter, may be expressed as the urethane prepolymer EO content) is preferably 20.0 to 55.0% by mass, 25.0 to 55.0% by mass, or 30.00 to 52.5% by mass. By setting the proportion of alkylene oxide or the urethane prepolymer EO content within such a range, a polyurethane foam having excellent water absorption and the like can be obtained.

[0070] The proportion of alkylene oxide in one molecule of the urethane prepolymer or the urethane prepolymer EO content indicates the mass% of alkylene oxide or ethylene oxide contained in one molecule of the urethane prepolymer when the mass (number average molecular weight) of one molecule of the urethane prepolymer is 100% by mass.

[0071] Here, the urethane prepolymer EO content indicates the mass% of ethylene oxide contained in the urethane prepolymer when the total amount of the urethane prepolymer is 100% by mass.

[0072] <Water absorption> The water absorption amount of the foam layer measured by the following measurement method is preferably 10 g / g or more, and more preferably 15 g / g or more.

[0073] (Measurement method of water absorption amount) Measure based on BS EN 13726-1. Prepare a test piece of 50 mm × 50 mm × t 5 mm. Measure the mass of the test piece before immersion. Immerse the test piece in an evaluation liquid having a mass 40 times the measured mass at 37°C for 30 minutes. After hanging the immersed test piece for 20 seconds, measure the mass. Calculate the water absorption amount according to the following formula. Water absorption amount = [(mass after immersion - mass before immersion) / mass before immersion]

[0074] By using such a foam layer, it becomes easier to sufficiently hold exudate, chemical solution, etc., and by preventing drying, it is considered to be excellent in function as a wound dressing material. By using such a foam layer, furthermore, it tends to be easy to obtain a laminate excellent in the peel strength between the base material layer and the foam layer.

[0075] <Water absorption rate> The water absorption rate of the foam layer measured by the following measurement method is preferably 3.0 seconds or less, and more preferably 1.5 seconds or less.

[0076] (Measurement method of water absorption rate) Measure based on JIS L 1907. Drop 1 drop of the evaluation liquid at 37°C from a height of 1 cm onto the test piece. The time from when the evaluation liquid is dropped until it is completely absorbed by the test piece is defined as the water absorption rate.

[0077] By using such a foam layer, it becomes easier to sufficiently hold exudate, chemical solution, etc., and by preventing drying, it is considered to be excellent in function as a wound dressing material.

[0078] <Density> The density of the foam layer is, for example, 30~150 kg / m 3 or 50~120 kg / m 3It is preferably such. The density of the foam layer can be measured in accordance with JIS K7222:2005 "Foamed Plastics and Rubbers - Method for Measuring Apparent Density". Specifically, the density of the foam layer can be obtained as a value obtained by processing the foam layer into a length of 100 mm × width of 100 mm × thickness of 2 mm and dividing the measured mass by the volume.

[0079] By using such a foam layer, it becomes easier to sufficiently hold exudate, chemical solution, etc., and by preventing drying, it is considered to be excellent in the function as a wound dressing material.

[0080] <<<Physical Properties / Properties>>> <<Peeling Strength before Water Immersion>> The peeling strength (peeling strength before water immersion) of the laminate measured by the following method is preferably 2.0 N / 24 mm or more, 3.0 N / 24 mm or more, or 4.0 N / 24 mm or more.

[0081] (Method for Measuring Peeling Strength before Water Immersion) Attach the first double-sided tape to the foam layer side of the laminate and mold it into a width of 24 mm × length of 11 mm. Attach a PET film to the base material side of the laminate via the second double-sided tape. Cure at 60 °C for 90 minutes. Attach the first double-sided tape to the SUS plate. Move a 2 kg roller back and forth on the foam layer for 5 seconds each to obtain a measurement sample. Perform 90° peeling with an autograph (1 kN) to measure the peeling strength. In the present disclosure, as the double-sided tapes (the first double-sided tape and the second double-sided tape) used in each test, No. 5000NS manufactured by Nitto Denko Corporation is used.

[0082] <<Peeling Strength after Water Immersion>> The peeling strength (peeling strength after water immersion) of the laminate measured by the following method is preferably 0.5 N / 24 mm or more, 0.8 N / 24 mm or more, or 1.1 N / 24 mm or more.

[0083] (Method for Measuring Peeling Strength after Water Immersion) Attach the first double-sided tape to the foam layer surface of the laminate and form it into a shape with a width of 24 mm and a length of 11 mm. Attach a PET film to the base material surface of the laminate via the second double-sided tape. Cure at 60 °C for 90 minutes. Attach the first double-sided tape to the SUS plate. Move a 2 kg roller back and forth on the foam layer for 5 seconds each to obtain a measurement sample. Immerse the measurement sample in ion-exchanged water at 37 °C for 1 hour. Lift the measurement sample out of the ion-exchanged water. Wipe off the moisture on the surface of the measurement sample and perform 90° peeling with an autograph (1 kN) to measure the peel strength.

[0084] <<Water vapor transmission rate>> The water vapor transmission rate of the laminate measured by the following method is 100 g / m 2 or more, 500 g / m 2 or more, 800 g / m 2 or more, 1000 g / m 2 or more, 1500 g / m 2 or more, or 2000 g / m 2 or more is preferable. The upper limit value of the water vapor transmission rate is, for example, 3000 g / m 2 . By setting the water vapor transmission rate within such a range, it is easy to obtain a laminate having excellent performance. In particular, when the water vapor transmission rate is 500 - 3000 g / m 2 , it tends to be excellent in peel strength before and after water immersion.

[0085] The water vapor transmission rate is measured based on Method A-1 (cup method) of the water vapor permeability test (JIS L 1099). Put the test sample set in the cup according to the standard into a thermo-hygrostat at 40 °C and 90% RH. After 1 hour, take out the test sample and measure its mass (a1). Put the test sample back at the same position in the thermo-hygrostat and after 24 hours, take out the test sample and measure its mass (a2). Calculate the water vapor transmission rate from the following formula. Water vapor transmission rate = [(a2 - a1) / water vapor permeable area]

[0086] <<<Manufacturing method>>> Hereinafter, an example of the manufacturing method of the laminate will be shown.

[0087] The manufacturing method of the laminate is obtained by foaming and curing a foam composition on a substrate. More specifically, the manufacturing method of the laminate includes a step of applying a composition for forming a foam (foam composition) (coating step), and a step of foaming and curing the foam composition (reaction step). Further, the manufacturing method of the laminate may include a step of preparing a foam composition containing a urethane prepolymer (adjustment step).

[0088] <<Adjustment Step>> Prepare a foam composition containing a urethane prepolymer and a foaming agent. The foam composition may contain, if necessary, a foam stabilizer, a pH adjuster, etc. Further, the foam composition may contain the other components described above.

[0089] The urethane prepolymer can be manufactured, for example, as follows.

[0090] Into a reaction vessel containing a predetermined amount of polyisocyanate, a predetermined amount of polyol and, if necessary, a catalyst are dropped, and then the inside of the reaction vessel is heated and stirred to react the polyisocyanate and the polyol to manufacture a urethane prepolymer. The reaction temperature is not particularly limited, but is usually 50 to 120°C, preferably 60 to 100°C. The reaction time is not particularly limited, but is usually 1 to 15 hours.

[0091] The polyol, polyisocyanate, etc. are as described above.

[0092] As the catalyst, known ones used in the manufacture of polyurethane foams can be used. For example, amine-based catalysts, organometallic-based catalysts, etc. can be mentioned.

[0093] Examples of the amine-based catalyst include triethylenediamine, diethanolamine, dimethylaminomorpholine, N-ethylmorpholine, etc.

[0094] Examples of the organometallic catalysts include stannous octoate, dibutyltin dilaurate, lead octenoate, potassium octylate, and the like.

[0095] The catalyst can be used alone or in combination of two or more.

[0096] When the total amount of the urethane prepolymer is 100 parts by mass, the compounding amount of the catalyst is preferably 0.001 to 5.0 parts by mass.

[0097] The blowing agent is not particularly limited. Examples of the blowing agent include water and alcohols. These can be used alone or in combination of two or more.

[0098] The blowing agent preferably contains water. When water is used as the blowing agent, carbon dioxide gas is generated during the reaction between the isocyanate groups contained in the prepolymer and water, and the polyurethane foam is foamed by the carbon dioxide gas.

[0099] When the urethane prepolymer is 100 parts by mass, the compounding amount of the blowing agent is preferably 10 to 40 parts by mass, and more preferably 15 to 30 parts by mass.

[0100] The foam stabilizer is not particularly limited. Any foam stabilizer can be used as long as it is commonly used as a raw material for polyurethane foam. Examples thereof include silicone compounds and nonionic surfactants. The foam stabilizer preferably has an alkylene oxide structure (for example, an ethylene oxide structure). Two or more foam stabilizers may be used in combination. The foam stabilizer preferably includes those having an HLB of 8 to 20, 9 to 15, or 9 to 12. The HLB of the foam stabilizer is determined by, for example, the Griffin method.

[0101] When the compounding amount of the urethane prepolymer is 100 parts by mass, the compounding amount of the foam stabilizer can be 0.1 to 10.0 parts by mass.

[0102] <<Coating Process>> In the coating process, the foam composition is coated onto a substrate.

[0103] In the coating process, the surface of the foam composition opposite to the surface in contact with the substrate may be covered with a release film. As the release film, known ones (such as silicone release films) can be used.

[0104] As the coating means, for example, known coating means such as an air knife coater, a blade coater, a knife coater, a roll coater, a cast coater, etc. can be used. The coating conditions (coating speed, etc.) can be appropriately adjusted according to the shape of the desired polyurethane foam, etc.

[0105] If necessary, a stirring process for stirring the foam composition may be carried out prior to the coating process.

[0106] The stirring process is carried out to uniformly mix the components of the foam composition. When the components in the foam composition are sufficiently homogenized, there is no need to carry out the stirring process.

[0107] The stirring process can be carried out using known stirring means such as a mixer.

[0108] The stirring conditions of the stirring process may be appropriately selected according to the viscosity of the foam composition, the components to be blended, etc.

[0109] <<Reaction Process>> The reaction process is usually carried out at a temperature of 15 to 120°C, preferably 15 to 60°C. The reaction time is usually 1 to 10 minutes.

[0110] Through the above processes, the foam according to the present disclosure is manufactured. For the foam thus obtained, a drying process may be carried out if necessary. Examples of the drying process include exposing the foam to an environment of 80 to 120°C using a heating furnace, a microwave oven, high-frequency induction heating, hot air drying, etc. The substrate can be removed as appropriate.

[0111] <<<Use / Usage>>> The laminate can be preferably used as a medical member (particularly, a wound dressing material, etc.). Further, the laminate may be used for other applications such as wiping materials, seedling growing media, sanitary products, etc.

[0112] When the laminate is used as a wound dressing material, the foam layer surface of the laminate is brought into contact with the wound portion for use. Further, if necessary, the laminate may be fixed to the wound portion using a bandage, an adhesive tape, or the like.

Examples

[0113] Hereinafter, the laminate will be specifically described with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

[0114] <<<Example 1>>> <<Preparation of Base Material>> As the base material, DS438-CD manufactured by Sheedom Co., Ltd., which is a thermoplastic polyurethane film (ester / aromatic TPU film) obtained from an ester-based polyol and an aromatic polyisocyanate, was used.

[0115] <<Manufacture of Urethane Prepolymer>> As raw materials, 24.3 parts by mass of Polyol I shown below, 24.3 parts by mass of Polyol II, 25.8 parts by mass of polyethylene glycol, 25.6 parts by mass of polyisocyanate, and a catalyst to be 20 ppm of the total amount of the composition were weighed into a reaction vessel, heated so as to be in a temperature range of 55 °C ± 5 °C, and reacted for 4 hours to produce a urethane prepolymer (a composition containing the urethane prepolymer), which was used as the first liquid. <Polyol I> Random type polyol Copolymer of ethylene oxide / propylene oxide Average functionality number 2 Number average molecular weight 1000 EO content 50% by mass Hydroxyl value 112.1 mgKOH / g <Polyol II> Random polyol Ethylene oxide / propylene oxide copolymer Average functionality: 3 Number average molecular weight: 1500 EO content: 70% by mass Hydroxyl value: 112.1 mg KOH / g <Polyethylene glycol (PEG1000)> Average functionality: 2 Number average molecular weight: 1000 EO content: 100% by mass Hydroxyl value: 113 mg KOH / g <Polyisocyanate> Hexamethylene diisocyanate (HDI) <Catalyst> KAT 716LA manufactured by TIB Chemical

[0116] The resulting urethane prepolymer had an average functionality of 2.3, an NCO% of 6.2%, a viscosity at 25°C of 4400 mPa·s, and a number average molecular weight of 4400.

[0117] Table 1 shows the contact angle of the substrate measured according to the above method [contact angle with respect to the urethane prepolymer (first liquid)].

[0118] <<Preparation of Foam Composition>> 100 parts by mass of urethane prepolymer and 28.5 parts by mass of blowing agent (water) were mixed. Further, a foam stabilizer [Pluronic (registered trademark) L-64 (HLB: 10)] was mixed in an amount of 1.5 parts by mass per 100 parts by mass of the urethane prepolymer to prepare a foam composition.

[0119] <<Manufacture of Laminate>> Using a roll coater, the foam composition was cast onto the substrate while adjusting the clearance so that the thickness after foaming would be 5 mm. Further, a release sheet was inserted onto the foam composition, and in a state where the foam composition was sandwiched by the substrate, it was foamed and cured at 50 to 60 °C. After curing (5 minutes later), the release sheet was removed, and it was heated in a drying oven at 80 °C until it was completely dried, obtaining a laminate including the substrate and the polyurethane foam.

[0120] The polyurethane foam contained in the obtained laminate had a water absorption of 20 g / g, a water absorption rate of 0.4 seconds, and a density of 80 kg / m 3 and was.

[0121] <<<Example 2-8>>> A laminate according to Example 2-8 was produced, except that the substrate was changed to those shown in Table 1. In the case where the substrate was a commercially available product, the product number and manufacturer name were set to those shown in Table 1.

[0122] <<<Comparative Example 1>>> A laminate according to Comparative Example 1 was produced in the same manner as in Example 1, except that the substrate was a polyethylene film (PE film) with a thickness of 0.020 mm.

[0123] <<<<Evaluation>>>> Based on the method described above, the peel strength before water immersion, the peel strength after water immersion, and the moisture permeability of each laminate were measured. Also, regarding the peel strength before water immersion and the peel strength after water immersion, evaluation was performed according to the following criteria. The measurement results and evaluation results are shown in Table 1.

[0124] <Evaluation Criteria for Peel Strength before Water Immersion> A: 4.0 N / 24 mm or more B: 3.0 N / 24 mm or more and less than 4.0 N / 24 mm C: 2.0 N / 24 mm or more and less than 3.0 N / 24 mm D: Less than 2.0 N / 24 mm

[0125] <Evaluation Criteria for Peel Strength after Water Immersion> A: 1.1 N / 24 mm or more B: Above 0.8 N / 24 mm and less than 1.1 N / 24 mm C: Above 0.5 N / 24 mm and less than 0.8 N / 24 mm D: Less than 0.5 N / 24 mm

[0126]

Table 1

Industrial Applicability

[0127] The laminate according to the present invention is considered to be easily capable of sufficiently retaining exudate, chemical solution, etc. Further, it is excellent in peel strength when in contact with a liquid. Therefore, it can be preferably used as a wound dressing material.

Claims

1. It has a base material and a foam layer directly laminated on one surface of the base material, The material of the base material is thermoplastic polyurethane, The foam layer is polyurethane foam, A laminate in which the water absorption of the polyurethane foam measured by the following measurement method is 10 g / g or more. (Measurement method) Measurement is performed based on BS EN 13726-1. Prepare a test piece of 50 mm × 50 mm × t 5 mm. Measure the mass of the test piece before immersion. Immerse the test piece in an evaluation liquid having a mass 40 times the measured mass at 37°C for 30 minutes. After hanging the immersed test piece for 20 seconds, measure the mass. Calculate the water absorption according to the following formula. Water absorption = [(mass after immersion - mass before immersion) / mass before immersion]

2. The laminate according to claim 1, wherein the contact angle of the base material measured by the following measurement method is 40° or less. (Measurement method) Prepare a urethane prepolymer contained in the foam composition which is the raw material of the foam layer as the liquid for measuring the contact angle. Install the microscope horizontally and focus it. Next, drop the urethane prepolymer droplet onto the base material with a syringe. Measure the contact angle with an image taken with a microscope 15 seconds after the droplet is dropped. Measure the contact angle at three locations on the base material, calculate the average value, and use it as the contact angle.

3. The laminate according to claim 1, wherein the peel strength measured by the following measurement method is 0.8 N / 24 mm or more. (Measurement method) Attach a first double-sided tape to the foam layer surface of the laminate and form it into a width of 24 mm × length of 11 mm. Attach a PET film to the base material surface of the laminate via a second double-sided tape. Cure at 60°C for 90 minutes. Attach the first double-sided tape to a SUS plate. Move a 2 kg roller back and forth on the foam layer for 5 seconds each to obtain a measurement sample. Immerse the measurement sample in ion-exchanged water at 37°C for 1 hour. Pull the measurement sample out of the ion-exchanged water. Wipe off the moisture on the surface of the measurement sample and perform 90° peeling with an autograph (1 kN) to measure the peel strength.

4. A wound dressing comprising the laminate according to any one of claims 1 to 3.

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