Preparation method of elastic sanitary material

Abstract

The invention relates to the technical field of filter materials, and discloses a preparation method of an elastic sanitary material, according to the method, a spunbond layer and a melt-blown layer are compounded by adopting a compound process of needling, cold pressing and stretching, the spunbond layer is of a skin-core structure comprising a PE resin skin layer and a PP resin core layer, the melt-blown layer is a TPU melt-blown layer, and the melt-blown layer is a thermoplastic polyurethane elastomer melt-blown layer. Fibers of the spunbond layer are punctured into the melt-blown layer through needling treatment, the connectivity between the fibers of the spunbond layer and the fibers of the melt-blown layer is improved, then cold pressing is conducted on needling points to melt PP resin on the surface layers of the fibers of the spunbond layer, the melted PP resin on the surfaces of the fibers, punctured into the melt-blown layer, of the spunbond layer can achieve the bonding effect, the bonding strength is further enhanced, and the bonding strength is improved. Meanwhile, the needling holes can be shrunk under the cold pressing effect through cold pressing, then the needling holes of the spunbond layer can be closed and pressing points can be leveled through stretching, the uniformity of the surface of the spunbond layer is remarkably improved, and the elastic material is soft, high in skin fitting degree, high in air permeability, remarkably improved in use comfort and free of hard hand feeling.

Description

Technical Field

[0001] The invention relates to the technical field of filter materials, in particular to a method for preparing an elastic sanitary material. Background Art

[0002] Sanitary napkins are an important sanitary product. Their structure consists of a high water absorbent layer, an edging layer arranged at the bottom of the high water absorbent layer, and a surface layer arranged on the high water absorbent layer. One side of the edging layer is in contact with the clothes, and the other side is in contact with the high water absorbent layer to prevent the liquid after absorption from contacting the clothes and contaminating the clothes. Usually, the area of ​​the edging layer is designed to be larger than that of the high water absorbent layer, so that after the edging layer and the high water absorbent layer are compounded, an outer edge structure can be formed at the edge of the high water absorbent layer. The outer edge structure can effectively prevent side leakage.

[0003] On the one hand, the edging layer needs to block the water-absorbing layer and clothing, and on the other hand, the outer edge structure formed by the edging layer will contact the skin. Therefore, the edging layer needs to meet the performance conditions of being waterproof, breathable, skin-friendly and soft. The material of the edging layer in the current prior art is usually made of a composite of multiple non-woven fabrics with different functions, such as a sanitary care base film and a preparation method thereof disclosed in CN115648778A. The technical scheme consists of a non-woven fabric layer, a breathable layer and a waterproof layer. The non-woven fabric layer is SMS non-woven fabric, the breathable film is TPU or PE film, and the waterproof film is PTFE film. The three-layer structure is composited by an ultrasonic welding machine. In actual use, the present application found that when an ultrasonic electric welder is used to weld the composite layer, the welding point will be welded into a solid at high temperature, and a solid will be formed inside this part of the welding point, which will cause the air permeability of the base film to be significantly reduced. Therefore, in order to reduce the influence of the welding process on spot welding, it is necessary to conduct in-depth research on the composite process of the edging layer. Summary of the invention

[0004] Aiming at the problem that the uniformity and air permeability of the material are significantly reduced after the non-woven fabric and the melt-blown fabric are composited by the welding technology, the present invention provides a preparation method of an elastic sanitary material. The method adopts a composite process of acupuncture, cold pressing and stretching to composite a spunbond layer and a melt-blown layer. The spunbond layer is a skin-core structure of a PE resin skin layer and a PP resin core layer, and the melt-blown layer is a TPU melt-blown layer. The fibers of the spunbond layer are penetrated into the melt-blown layer by acupuncture treatment, so as to improve the connectivity between the fibers of the spunbond layer and the fibers of the melt-blown layer. Then, the PP resin on the surface of the spunbond layer fibers is melted by cold pressing at the acupuncture points, so that the melted PP resin on the surface of the spunbond layer fibers penetrated into the melt-blown layer can play a bonding role, further enhancing the bonding strength. At the same time, the cold pressing can also shrink the acupuncture holes under the action of the cold pressing. Then, the acupuncture holes of the spunbond layer can be closed and the pressure points can be flattened by stretching, so that the uniformity of the surface of the spunbond layer is significantly improved. The elastic material is soft, has a high degree of skin fit, high air permeability, significantly improved comfort in use and no hard knot feel.

[0005] The specific technical scheme of the present invention is: A method for preparing an elastic sanitary material comprises the following steps: The spunbond layer is compounded on the surface of the meltblown layer to make an elastic sanitary material. The fiber of the spunbond layer is a skin-core structure, wherein the skin-core structure has PE resin as the skin layer and PP resin as the core layer, and the fiber of the meltblown layer is TPU resin. The composite method includes acupuncture, cold pressing and stretching; The conditions for the acupuncture include: the number of acupunctures is 1 to 5, and the acupuncture direction is from the spunbond layer to the meltblown layer; The cold pressing conditions include: the cold pressing point area is 3-20%, the cold pressing temperature is 125-135°C; The stretching conditions include: stretching in the warp and weft directions, and a stretching strength of 30 to 50 N / 50 m.

[0006] The present invention provides a method for preparing an elastic sanitary material, in which a spunbond cloth and a meltblown cloth are composited to prepare the elastic material, the fiber of the meltblown cloth is TPU resin, and the TPU resin can make the elastic material have super high wrinkle resistance, water resistance and air permeability, the fiber of the spunbond cloth is a skin-core structure of a skin layer of PE resin and a core layer of PP resin, the spunbond cloth has an ultra-soft touch and excellent waterproof and breathable properties, is extremely comfortable to contact with the skin, and significantly improves the user experience; the traditional composite process often uses an infrared welding process to weld and composite the spunbond layer and the meltblown layer, but the present invention finds that after the welding and composite, the composite point will melt, solidify and condense into a whole, and at the same time, the pore structure inside the fiber is destroyed during welding, resulting in a significant reduction in the air permeability of the material.

[0007] Therefore, in order to solve the above problems, the present invention provides a composite method of acupuncture, cold pressing and stretching. The meltblown layer is first pierced from the spunbond layer by acupuncture treatment, and the spunbond layer fibers will be pierced into the meltblown layer and entangled with the meltblown layer. Then, the acupuncture point is pressed by a pressure head. The cold pressing head is set to a specific temperature. At the specific temperature, the PE resin of the skin layer of the spunbond layer fibers will melt, while the PP resin of the core layer will remain in a solidified state. The melted PE resin will bond at the entanglement point, so that the spunbond layer fibers form anchor points inside the meltblown layer, which significantly enhances the composite strength of the spunbond layer and the meltblown layer. The acupuncture holes can be squeezed and reduced during the cold pressing process, and then the pressure generated during the cold pressing is reduced by stretching treatment. The marks are flattened and the pinholes are pulled closed, so that the uniformity of the surface of the spunbond layer is improved. The elastic sanitary material prepared by this composite method has high surface uniformity and high flatness, and has a high degree of skin fit when used. At the same time, there are no hard nodes produced after welding, and the comfort of use is significantly improved. The internal meltblown layer fiber structure of the prepared elastic sanitary material is not destroyed, so that the air permeability of the meltblown material will not be significantly changed. In addition, the composite strength of the meltblown layer and the spunbond layer after composite method is significantly higher than that of the meltblown layer and the spunbond layer using only the needle punching process, and it can still not be delaminated under continuous high-intensity rubbing treatment, so that users have an excellent use experience during high-intensity exercise.

[0008] Preferably, the spunbond layer is made by spunbonding PP resin and PE resin.

[0009] Preferably, the conditions of the spunbond process include: melt-kneading the PP resin to form molten PP, melt-kneading the PE resin to form molten PE, injecting the molten PP and the molten PE into a screw extruder to extrude a composite PP / PE melt, injecting the composite PP / PE melt into a spinning device for spinning and stretching to form filaments, and placing the filaments in a web forming device to form a spunbond layer.

[0010] Preferably, the fibers of the spunbond layer are of a sheath-core structure, wherein the PP resin is the core layer and the PE resin is the sheath layer, and the mass ratio of the core layer to the sheath layer is 3 to 7:1.

[0011] Preferably, the spunbond layer has a grammage of 5 to 20 g / m.

[0012] Preferably, the meltblown layer is made of TPU resin raw material by sequentially subjecting it to screw extrusion reaction and meltblowing process.

[0013] Preferably, the TPU resin raw material includes: isocyanate, polyol, chain extender and catalyst, the isocyanate is one or more of aliphatic diisocyanate and aromatic diisocyanate, the polyol is one or more of polyester polyol and polyether polyol, the chain extender is one or more of ethylene glycol, butanediol, ethylene glycol and hydroquinone dihydroxyethyl ether, and the catalyst is one or more of tertiary amine catalyst and organic metal catalyst.

[0014] Preferably, the conditions of the screw extrusion reaction include: a reaction temperature of 150 to 220°C.

[0015] Preferably, the conditions of the meltblowing process include: meltblowing die head temperature 210-270°C, hot air temperature 210-270°C, and air pressure 0.1-0.5 MPa.

[0016] Preferably, the meltblown layer has a gram weight of 3 to 15 g / cm2.

[0017] Compared with the prior art, this application has the following technical effects: The invention provides a preparation method of an elastic sanitary material. The method adopts a composite process of needling, cold pressing and stretching to composite a spunbond layer and a meltblown layer. The spunbond layer is a skin-core structure of a PE resin skin layer and a PP resin core layer, and the meltblown layer is a TPU meltblown layer. Needling treatment is performed to allow fibers of the spunbond layer to penetrate into the meltblown layer, thereby improving connectivity between the fibers of the spunbond layer and the fibers of the meltblown layer. Cold pressing is then performed on the needling points to melt the PP resin on the surface of the fibers of the spunbond layer, so that the melted PP resin on the surface of the fibers of the spunbond layer penetrated into the meltblown layer can play a bonding role, thereby further enhancing the bonding strength. Meanwhile, cold pressing can also shrink the puncture holes under the action of cold pressing. Stretching can close the puncture holes of the spunbond layer and flatten the pressure points, thereby significantly improving the uniformity of the surface of the spunbond layer. The elastic material is soft, has a high degree of skin fit, is highly breathable, has significantly improved comfort in use, and has no hard knot feel. DETAILED DESCRIPTION

[0018] The present invention will be further described below in conjunction with the embodiments.

[0019] Embodiment 1: A method for preparing an elastic sanitary material, characterized in that it comprises the following steps: Preparation of meltblown layer: isocyanate (diphenylmethane diisocyanate), polyol (polybutylene adipate, molecular weight 2000g / mol), chain extender (butylene glycol) and catalyst (dibutyltin dilaurate) are uniformly dispersed in polybutylene adipate, and then the dispersed isocyanate, polyol and chain extender are added to a twin-screw extruder at flow rates of 5.27g / s, 10.08g / s and 1.45g / s, respectively, and a catalyst (50ppm) is added for reaction. The melt after the reaction is transported to the meltblown net in the meltblown die by a melt pump to obtain a meltblown layer. The temperature of the screw reaction zone of the twin-screw extruder is 200-250°C, the temperature of the meltblown die is 250°C, the temperature of the hot air is 250°C, and the gram weight of the meltblown layer is 10g / cm2; Preparation of spunbond layer: PP resin (melt flow rate of 14-75g / 10min) is injected into a screw extruder at a temperature of 165°C to make molten PP, and PE resin (melt flow rate of 50-100g / 10min) is injected into a screw extruder at a temperature of 135°C to make molten PE. The molten PP and molten PE are respectively injected into the spinning box, and then the skin layer is PE resin and the core layer is PP resin melt-spun through the spinneret. The mass ratio of the core layer to the skin layer is 5:1. The melt spinning enters the air and is blown, stretched and cooled to form filaments. The filaments are cross-distributed with the adjacent filaments on the web-forming machine through the swinging device to form a fiber web to form a spunbond layer. The gram weight of the spunbond layer is 12g / m; The meltblown layer and the spunbond layer are composited: a layer of the spunbond layer prepared above is stacked on the surface of the meltblown layer and subjected to a needle punching treatment to form a composite layer, and then a layer of spunbond cloth is stacked on the surface of the meltblown layer of the composite layer and subjected to a needle punching treatment; the needle punching treatment conditions are: the number of needle punches is 2, and the needle punching direction is from the spunbond layer to the meltblown layer; then a cold pressing roller is used to cold press to form a preform, the pressure point area of ​​the cold pressing is 5%, and the temperature of the cold pressing roller is 130°C; then the preform is heat-dried at a temperature of 85°C and then stretched in the warp and weft directions to form an elastic sanitary material, and the stretching strength is 40N / 50m.

[0020] Embodiment 2: A method for preparing an elastic sanitary material, characterized in that it comprises the following steps: Preparation of meltblown layer: isocyanate (diphenylmethane diisocyanate), polyol (polybutylene adipate, molecular weight 2000g / mol), chain extender (butylene glycol) and catalyst (dibutyltin dilaurate) are uniformly dispersed in polybutylene adipate, and then the dispersed isocyanate, polyol and chain extender are added to a twin-screw extruder at flow rates of 5.27g / s, 10.08g / s and 1.45g / s, respectively, and a catalyst (50ppm) is added for reaction. The melt after the reaction is transported to the meltblown net in the meltblown die by a melt pump to obtain a meltblown layer. The temperature of the screw reaction zone of the twin-screw extruder is 200-250°C, the temperature of the meltblown die is 250°C, the temperature of the hot air is 250°C, and the gram weight of the meltblown layer is 3g / cm2; Preparation of spunbond layer: PP resin (melt flow rate of 14-75g / 10min) is injected into a screw extruder at a temperature of 165°C to make molten PP, and PE resin (melt flow rate of 50-100g / 10min) is injected into a screw extruder at a temperature of 135°C to make molten PE. The molten PP and molten PE are respectively injected into the spinning box, and then the skin layer is PE resin and the core layer is PP resin melt-spun through the spinneret. The mass ratio of the core layer to the skin layer is 3:1. The melt spinning enters the air and is blown, stretched and cooled to form filaments. The filaments are cross-distributed with the adjacent filaments on the web-forming machine through the swinging device to form a fiber web to form a spunbond layer. The gram weight of the spunbond layer is 5g / m; The meltblown layer and the spunbond layer are composited: a layer of the spunbond layer prepared above is stacked on the surface of the meltblown layer and subjected to a needle-punching treatment to form a composite layer, and then a layer of spunbond cloth is stacked on the surface of the meltblown layer of the composite layer and subjected to a needle-punching treatment; the needle-punching treatment conditions are: the number of needle punches is 1, and the needle-punching direction is from the spunbond layer to the meltblown layer; then a cold pressing roller is used to cold press to form a preform, the pressure point area of ​​the cold pressing is 3%, the temperature of the cold pressing roller is 125°C, and then the preform is heat-dried at a temperature of 80°C and then stretched in the warp and weft directions to form an elastic sanitary material, and the stretching strength is 30N / 50m.

[0021] Embodiment 3: A method for preparing an elastic sanitary material, characterized in that it comprises the following steps: Preparation of meltblown layer: isocyanate (diphenylmethane diisocyanate), polyol (polybutylene adipate, molecular weight 2000g / mol), chain extender (butylene glycol) and catalyst (dibutyltin dilaurate) are uniformly dispersed in polybutylene adipate, and then the dispersed isocyanate, polyol and chain extender are added to a twin-screw extruder at flow rates of 5.27g / s, 10.08g / s and 1.45g / s, respectively, and a catalyst (50ppm) is added for reaction. The melt after the reaction is transported to the meltblown net in the meltblown die by a melt pump to obtain a meltblown layer. The temperature of the screw reaction zone of the twin-screw extruder is 200-250°C, the temperature of the meltblown die is 250°C, the temperature of the hot air is 250°C, and the gram weight of the meltblown layer is 15g / cm2; Preparation of spunbond layer: PP resin (melt flow rate of 14-75g / 10min) is injected into a screw extruder at a temperature of 165°C to make molten PP, and PE resin (melt flow rate of 50-100g / 10min) is injected into a screw extruder at a temperature of 135°C to make molten PE. The molten PP and molten PE are respectively injected into the spinning box, and then the skin layer is PE resin and the core layer is PP resin melt-spun through the spinneret. The mass ratio of the core layer to the skin layer is 7:1. The melt spinning enters the air and is blown, stretched and cooled to form filaments. The filaments are cross-distributed with the adjacent filaments on the web-forming machine through the swinging device to form a fiber web to form a spunbond layer. The gram weight of the spunbond layer is 20g / m; The meltblown layer and the spunbond layer are composited: a layer of the spunbond layer prepared above is stacked on the surface of the meltblown layer and subjected to a needle punching treatment to form a composite layer, and then a layer of spunbond cloth is stacked on the surface of the meltblown layer of the composite layer and subjected to a needle punching treatment; the needle punching treatment conditions are: the number of needle punches is 5, and the needle punching direction is from the spunbond layer to the meltblown layer; then a cold pressing roller is used to cold press to form a preform, the pressure point area of ​​the cold pressing is 20%, and the temperature of the cold pressing roller is 135°C, and then the preform is heat-dried at a temperature of 90°C and then stretched in the warp and weft directions to form an elastic sanitary material, and the stretching strength is 50N / 50m.

[0022] Embodiment 4: A method for preparing an elastic sanitary material, characterized in that it comprises the following steps: Preparation of meltblown layer: isocyanate (diphenylmethane diisocyanate), polyol (polybutylene adipate, molecular weight 2000g / mol), chain extender (butylene glycol) and catalyst (dibutyltin dilaurate) are uniformly dispersed in polybutylene adipate, and then the dispersed isocyanate, polyol and chain extender are added to a twin-screw extruder at flow rates of 5.27g / s, 10.08g / s and 1.45g / s, respectively, and a catalyst (50ppm) is added for reaction. The melt after the reaction is transported to the meltblown net in the meltblown die by a melt pump to obtain a meltblown layer. The temperature of the screw reaction zone of the twin-screw extruder is 200-250°C, the temperature of the meltblown die is 250°C, the temperature of the hot air is 250°C, and the gram weight of the meltblown layer is 10g / cm2; Preparation of spunbond layer: PP resin (melt flow rate of 14-75g / 10min) is injected into a screw extruder at a temperature of 165°C to form molten PP, and PE resin (melt flow rate of 50-100g / 10min) is injected into a screw extruder at a temperature of 135°C to form molten PE. The molten PP and molten PE are respectively injected into the spinning box, and then the skin layer is PE resin and the core layer is PP resin melt-spun through the spinneret. The mass ratio of the core layer to the skin layer is 4:1. The melt spinning enters the air and is blown, stretched and cooled to form filaments. The filaments are cross-distributed with the adjacent filaments on the web-forming machine through the swinging device to form a fiber web to form a spunbond layer. The gram weight of the spunbond layer is 15g / m; The meltblown layer and the spunbond layer are composited: a layer of the spunbond layer prepared above is stacked on the surface of the meltblown layer and subjected to a needle-punching treatment to form a composite layer, and then a layer of spunbond cloth is stacked on the surface of the meltblown layer of the composite layer and subjected to a needle-punching treatment; the needle-punching treatment conditions are: the number of needle punches is 3, and the needle-punching direction is from the spunbond layer to the meltblown layer; then a cold pressing roller is used to cold press to form a preform, the pressure point area of ​​the cold pressing is 8%, and the temperature of the cold pressing roller is 130°C, and then the preform is heat-dried at a temperature of 85°C and then stretched in the warp and weft directions to form an elastic sanitary material, and the stretching strength is 40N / 50m.

[0023] Embodiment 5: A method for preparing an elastic sanitary material, characterized in that it comprises the following steps: Preparation of meltblown layer: isocyanate (diphenylmethane diisocyanate), polyol (polybutylene adipate, molecular weight 2000g / mol), chain extender (butylene glycol) and catalyst (dibutyltin dilaurate) are uniformly dispersed in polybutylene adipate, and then the dispersed isocyanate, polyol and chain extender are added to a twin-screw extruder at flow rates of 5.27g / s, 10.08g / s and 1.45g / s, respectively, and a catalyst (50ppm) is added for reaction. The melt after the reaction is transported to the meltblown net in the meltblown die by a melt pump to obtain a meltblown layer. The temperature of the screw reaction zone of the twin-screw extruder is 200-250°C, the temperature of the meltblown die is 250°C, the temperature of the hot air is 250°C, and the gram weight of the meltblown layer is 12g / cm2; Preparation of spunbond layer: PP resin (melt flow rate of 14-75g / 10min) is injected into a screw extruder at a temperature of 165°C to make molten PP, and PE resin (melt flow rate of 50-100g / 10min) is injected into a screw extruder at a temperature of 135°C to make molten PE. The molten PP and molten PE are respectively injected into the spinning box, and then the skin layer is PE resin and the core layer is PP resin melt-spun through the spinneret. The mass ratio of the core layer to the skin layer is 6:1. The melt spinning enters the air and is blown, stretched and cooled to form filaments. The filaments are cross-distributed with the adjacent filaments on the web-forming machine through the swinging device to form a fiber web to form a spunbond layer. The gram weight of the spunbond layer is 13g / m; The meltblown layer and the spunbond layer are composited: a layer of the spunbond layer prepared above is stacked on the surface of the meltblown layer and subjected to a needle-punching treatment to form a composite layer, and then a layer of spunbond cloth is stacked on the surface of the meltblown layer of the composite layer and subjected to a needle-punching treatment; the needle-punching treatment conditions are: the number of needle punches is 3, and the needle-punching direction is from the spunbond layer to the meltblown layer; then a cold pressing roller is used to cold press to form a preform, the pressure point area of ​​the cold pressing is 10%, and the temperature of the cold pressing roller is 130°C, and then the preform is heat-dried at a temperature of 80 to 90°C and then stretched in the warp and weft directions to form an elastic sanitary material, and the stretching strength is 45N / 50m.

[0024] Embodiment 6: A method for preparing an elastic sanitary material, characterized in that it comprises the following steps: Preparation of meltblown layer: isocyanate (diphenylmethane diisocyanate), polyol (polybutylene adipate, molecular weight 2000g / mol), chain extender (butylene glycol) and catalyst (dibutyltin dilaurate) are uniformly dispersed in polybutylene adipate, and then the dispersed isocyanate, polyol and chain extender are added to a twin-screw extruder at flow rates of 5.27g / s, 10.08g / s and 1.45g / s, respectively, and a catalyst (50ppm) is added for reaction. The melt after the reaction is transported to the meltblown net in the meltblown die by a melt pump to obtain a meltblown layer. The temperature of the screw reaction zone of the twin-screw extruder is 200-250°C, the temperature of the meltblown die is 250°C, the temperature of the hot air is 250°C, and the gram weight of the meltblown layer is 10g / cm2; Preparation of spunbond layer: PP resin (melt flow rate of 14-75g / 10min) is injected into a screw extruder at a temperature of 165°C to make molten PP, and PE resin (melt flow rate of 50-100g / 10min) is injected into a screw extruder at a temperature of 135°C to make molten PE. The molten PP and molten PE are respectively injected into the spinning box, and then the skin layer is PE resin and the core layer is PP resin melt-spun through the spinneret. The mass ratio of the core layer to the skin layer is 7:1. The melt spinning enters the air and is blown, stretched and cooled to form filaments. The filaments are cross-distributed with the adjacent filaments on the web-forming machine through the swinging device to form a fiber web to form a spunbond layer. The gram weight of the spunbond layer is 15g / m; The meltblown layer and the spunbond layer are composited: a layer of the spunbond layer prepared above is stacked on the surface of the meltblown layer and subjected to a needle punching treatment to form a composite layer, and then a layer of spunbond cloth is stacked on the surface of the meltblown layer of the composite layer and subjected to a needle punching treatment; the needle punching treatment conditions are: the number of needle punches is 4, and the needle punching direction is from the spunbond layer to the meltblown layer; then a cold pressing roller is used to cold press to form a preform, the pressure point area of ​​the cold pressing is 15%, and the temperature of the cold pressing roller is 135°C; then the preform is heat-dried at a temperature of 85°C and then stretched in the warp and weft directions to form an elastic sanitary material, and the stretching strength is 48N / 50m.

[0025] Embodiment 7: A method for preparing an elastic sanitary material, characterized in that it comprises the following steps: Preparation of meltblown layer: isocyanate (diphenylmethane diisocyanate), polyol (polybutylene adipate, molecular weight 2000g / mol), chain extender (butylene glycol) and catalyst (dibutyltin dilaurate) are uniformly dispersed in polybutylene adipate, and then the dispersed isocyanate, polyol and chain extender are added to a twin-screw extruder at flow rates of 5.27g / s, 10.08g / s and 1.45g / s, respectively, and a catalyst (50ppm) is added for reaction. The melt after the reaction is transported to the meltblown net in the meltblown die by a melt pump to obtain a meltblown layer. The temperature of the screw reaction zone of the twin-screw extruder is 200-250°C, the temperature of the meltblown die is 250°C, the temperature of the hot air is 250°C, and the gram weight of the meltblown layer is 13g / cm2; Preparation of spunbond layer: PP resin (melt flow rate of 14-75g / 10min) is injected into a screw extruder at a temperature of 165°C to form molten PP, and PE resin (melt flow rate of 50-100g / 10min) is injected into a screw extruder at a temperature of 135°C to form molten PE. The molten PP and molten PE are respectively injected into a spinning box, and then the skin layer is PE resin and the core layer is PP resin melt-spun through a spinneret. The melt-spun fibers enter the air and are blown, stretched, and cooled to form filaments. The filaments are cross-distributed with the adjacent filaments on a web-forming machine through a swinging device to form a fiber web to form a spunbond layer. The spunbond layer has a gram weight of 18g / m; The meltblown layer and the spunbond layer are composited: a layer of the spunbond layer prepared above is stacked on the surface of the meltblown layer and subjected to a needle punching treatment to form a composite layer, and then a layer of spunbond cloth is stacked on the surface of the meltblown layer of the composite layer and subjected to a needle punching treatment; the needle punching treatment conditions are: the number of needle punches is 5, and the needle punching direction is from the spunbond layer to the meltblown layer; then a cold pressing roller is used to cold press to form a preform, the pressure point area of ​​the cold pressing is 16%, and the temperature of the cold pressing roller is 130°C, and then the preform is heat-dried at a temperature of 90°C and then stretched in the warp and weft directions to form an elastic sanitary material, and the stretching strength is 48N / 50m.

[0026] Comparative Example 1: Compared with Example 1, the composite method in Comparative Example 1 uses an ultrasonic fusion spot welding machine for fusion spot welding, the welding spot area of ​​fusion spot welding is 5%, and the other conditions are the same as those in Example 1.

[0027] Comparative Example 2: Compared with Example 1, the composite infrared band hot pressing roller in Comparative Example 2 has a pressure point area of ​​5%, and the other conditions are the same as those in Example 1.

[0028] Comparative Example 3: Compared with Example 1, no cold pressing treatment was used in Comparative Example 3, and the other conditions were the same as those in Example 1.

[0029] Comparative Example 4: Compared with Example 1, no acupuncture treatment was used in Comparative Example 4, and the other conditions were the same as those in Example 1.

[0030] Comparative Example 5: Compared with Example 1, no stretching treatment was performed in Comparative Example 5, and the other conditions were the same as those in Example 1.

[0031] Comparative Example 6: Compared with Example 1, the spunbond layer in Comparative Example 6 is made by melt spinning a blend of PP resin and PE resin, and the other conditions are the same as those in Example 1.

[0032] Comparative Example 7: Compared with Example 1, the cold pressing temperature of Comparative Example 7 is 80° C., and the other conditions are the same as those of the example.

[0033] Comparative Example 8: Compared with Example 1, the cold pressing temperature of Comparative Example 8 is 180° C., and the other conditions are the same as those of the example.

[0034] Test example: The peel strength, rubbing resistance, air permeability, waterproofness and surface smoothness of the elastic sanitary materials prepared in Examples 1 to 7 and Comparative Examples 1 to 8 were tested. The peel strength test method was based on GB / T8808-1988 T-type peel strength test method for soft composite plastics. The instrument used for the peel test was an XLW (PC) intelligent electronic tensile testing machine. The air permeability test method refers to GB / T5453-1997 "Determination of air permeability of textile fabrics" for air permeability test; the anti-rubbing test method: the above elastic sanitary material is rubbed with a Derek DRK268 rubbing tester, the rubbing conditions are 155mm, angle 440°, cycle 800, and after the rubbing is completed, the peel strength and air permeability after rubbing are tested with the above peel strength and air permeability test methods. The test results are shown in Table 1; Table 1 Test results As shown in Table 1, the air permeability of the elastic sanitary materials prepared in Examples 1 to 7 is between 8527 mm / s and 8614 mm / s, and the peel strength is between 7.5 N / M 2 Up to 9.2N / M 2 It has excellent air permeability and composite strength. In the wrinkle resistance test results of elastic sanitary materials, after rubbing 800 times, the air permeability is between 8527mm / s and 8614mm / s, and the peel strength is still 6.6N / M 2 Up to 7.4N / M 2It can be seen that the elastic sanitary material prepared by the present invention has excellent anti-rubbing properties, and the composite strength and air permeability will not be significantly reduced after high-intensity rubbing. In addition, the elastic material has no obvious creases and frizz after rubbing, and the softness and comfort have no significant changes, and the use experience is excellent.

[0035] Comparative Examples 1 and 2 respectively used ultrasonic spot welding and infrared band hot pressing rollers for welding and lamination. The results of Comparative Examples 1 and 2 showed that the peel strength of the elastic sanitary material after lamination was 8.2 N / M. 2 Up to 8.4N / M 2 The air permeability is only between 5421mm / s and 5829mm / s. Compared with Example 1, there is no significant difference in composite strength between Comparative Examples 1 and 2, but the air permeability is significantly reduced. In addition, the elastic sanitary materials of Comparative Examples 1 and 2 are damaged after rubbing. Due to welding or large welding hard spots, the welding hard spots damage the surrounding fibers during the rubbing process, resulting in damage to the elastic sanitary materials and poor anti-rubbing performance.

[0036] In Comparative Example 3, no cold pressing treatment was used, only needle punching and stretching treatment were used. The results showed that the peel strength of the elastic sanitary material only treated with needle punching was low, significantly lower than the peel strength of the embodiment.

[0037] Comparative Example 4 did not undergo acupuncture treatment and only used cold pressing and stretching treatments. The results showed that the peel strength of the elastic sanitary material only treated with cold pressing and stretching treatments was only 4.8, the peel strength was significantly reduced, and the application effect was good.

[0038] Comparative Example 5 was not stretched. Although the absence of stretching treatment had no significant effect on air permeability and peel strength, pressure point depressions and needle-puncture gaps appeared on the surface of the elastic material, resulting in a lower fit between the subsequent elastic material and the skin.

[0039] The fibers of the spunbond layer in Comparative Example 6 are made by blending PP resin and PE resin. The results show that the peel strength of Comparative Example 6 is only 4.6 N / M 2 Further analysis revealed that the spunbond fibers were deformed after melt blending, and their structural strength was significantly reduced. Effective entanglement points could not be formed inside the meltblown layer during needle punching, and the fibers that served as anchor points were easily broken during peeling.

[0040] In Comparative Examples 7 and 8, the cold pressing temperatures are respectively set to be too low and too high. If the cold pressing temperature is too low, the skin layer of the spunbond layer fiber filaments cannot be melted, resulting in the inability to form adhesion at the entanglement points, and the peel strength is significantly reduced. If the cold pressing temperature is too high, all the spunbond layer fiber filaments will melt, and the fibers will break before entering the meltblown layer during needle punching. After hot drying and stretching, the composite points will be pulled apart, and the composite strength will be significantly reduced.

[0041] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent transformation made to the above embodiment based on the technical essence of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A method for preparing an elastic sanitary material, characterized in that: The following steps are involved: The spunbond layer is compounded on the surface of the meltblown layer to make an elastic sanitary material. The fiber of the spunbond layer is a skin-core structure, wherein the skin-core structure has PE resin as the skin layer and PP resin as the core layer, and the fiber of the meltblown layer is TPU resin. The composite method includes acupuncture, cold pressing and stretching; The conditions for the acupuncture include: the number of acupuncture is 1 to 5, and the acupuncture direction is from the spunbond layer to the meltblown layer; The cold pressing conditions include: the cold pressing point area is 3-20%, and the cold pressing temperature is 125-135°C; The stretching conditions include: stretching in the warp and weft directions, and a stretching strength of 30-50 N / 50m.

2. The method for preparing the elastic sanitary material according to claim 1, characterized in that: The spunbond layer is made by using PP resin and PE resin through a spunbond process.

3. The method for preparing the elastic sanitary material according to claim 2, characterized in that: The conditions of the spunbond process include: melt-kneading PP resin to form molten PP, melt-kneading PE resin to form molten PE, injecting molten PP and molten PE into a screw extruder to extrude a composite PP / PE melt, injecting the composite PP / PE melt into a spinning device for spinning and stretching to form filaments, and placing the filaments in a web forming device to form a spunbond layer.

4. The method for preparing the elastic sanitary material according to any one of claims 1 or 2, characterized in that: The spunbond layer has a grammage of 5 to 20 g / m.

5. The method for preparing the elastic sanitary material according to claim 1, characterized in that: The mass ratio of the core layer to the skin layer is 3~7:

1.

6. The method for preparing the elastic sanitary material according to claim 1, characterized in that: The melt-blown layer is made of TPU resin raw material by sequentially subjecting it to screw extrusion reaction and melt-blowing process.

7. The method for preparing the elastic sanitary material according to claim 6, characterized in that: The TPU resin raw materials include isocyanate, polyol, chain extender and catalyst.

8. The method for preparing the elastic sanitary material according to claim 6, characterized in that: The conditions of the screw extrusion reaction include: a reaction temperature of 150-220°C.

9. The method for preparing the elastic sanitary material according to claim 6, characterized in that: The conditions of the melt-blowing process include: melt-blowing die temperature 210-270°C, hot air temperature 210-270°C, and air pressure 0.1-0.5 MPa.

10. The method for preparing the elastic sanitary material according to any one of claims 1 or 6, characterized in that: The meltblown layer has a gram weight of 3 to 15 g / cm2.

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