108 results about "Polyethylene terephtalate" patented technology

The application belongs to the technical field of plastics, and particularly relates to a degradable antibacterial plastic packaging bag and a preparation method thereof. The degradable antibacterial plastic packaging bag comprises the following raw materials in parts by weight: polycaprolactone 70-90 parts; polybutylene adipate terephthalate 20-40 parts; Cr and Cu co-modified ZIF-8 5-20 parts; and cerium oxide tannic acid material 2-6 parts. The Cr and Cu co-modified ZIF-8 synergistically improves the antibacterial performance of the packaging bag, and the addition of the cerium oxide tannic acid material further improves the antibacterial performance of the packaging bag. Moreover, the degradable antibacterial plastic packaging bag prepared by the application has excellent mechanical properties.

The invention belongs to the technical field of degradable packaging materials, and discloses a preparation method of a degradable preservative film. The anti-fog antibacterial plastic is prepared from the following raw materials in parts by weight: 40 to 45 parts of poly (butylene adipate-co-terephthalate) (PBAT), 8 to 12 parts of polylactic acid (PLA), 28 to 32 parts of modified structural starch, 4 to 6 parts of poly (butylene carbonate) (PBC), 4 to 6 parts of talcum powder, 0.4 to 0.6 part of aluminate, 0.8 to 1.2 parts of a composite antibacterial agent and 2.5 to 3.5 parts of anti-fog master batch. The invention aims to overcome the defects in the prior art, and provides the degradable preservative film and the preparation method thereof, the preservative film not only has good degradability and mechanical properties, but also has excellent antibacterial and antifogging effects, and the preparation process is simple and easy for industrial production.

The invention relates to the technical field of bio-based degradable high polymer materials, in particular to a bio-based degradable pearl wool microcellular foaming material. The composite material is prepared from the following components in parts by mass: 70-85 parts of a bio-based polyester resin composite system of polylactic acid and poly (terephthalic acid)-butylene adipate (in a mass ratio of 60: 40-75: 25), 10-20 parts of bagasse microfibers modified by a silane coupling agent, 1.5-4 parts of a composite nucleating agent of flaky talcum powder and spherical nano calcium carbonate (in a mass ratio of 1.5: 1-2.5: 1), the bio-based plasticizer is prepared by compounding epoxidized soybean oil and tributyl citrate, the montmorillonite degradation accelerant is loaded with iron and cobalt ions (the molar ratio is 3: 1-5: 1), and the mixed foaming agent is prepared from 5-12 parts of supercritical carbon dioxide and nitrogen (the volume ratio is 60%-85%). A bio-based polyester composite system of polylactic acid and PBAT is adopted, silane modified bagasse microfibers are matched, montmorillonite loaded with iron and cobalt ions serves as a degradation accelerant, a bio-based plasticizer and the like are combined, and the composite material is prepared through a twin-screw extrusion melt blending and supercritical fluid foaming technology.

The invention relates to the field of textile fabrics, and discloses a polylactic acid fabric and a preparation method thereof. The polylactic acid fabric is prepared by weaving polylactic acid fibers, the polylactic acid fibers are prepared by melt spinning of a polylactic acid material body, and the polylactic acid material body is prepared from the following raw materials in parts by weight: 100-120 parts of polylactic acid resin, 12-20 parts of a heat-resistant moisture absorbent, 6-10 parts of a toughening agent and 0.2-0.4 part of an antioxidant; the heat-resistant moisture absorbent is prepared from lignin fibers, poly (ethylene 2, 5-furandicarboxylate), poly (butylene adipate-co-terephthalate) and a dispersing agent. The preparation method comprises the following steps of melt spinning, rib knitting, heat setting, dyeing and aftertreatment. The polylactic acid fabric prepared by the invention has better heat resistance, moisture absorption and shrink deformation resistance, and is suitable for scenes with higher requirements on heat resistance and moisture absorption, such as underwear or infant clothes.

This application relates to the field of electrochemical technology, specifically to polyester composite films and their preparation methods, composite current collectors and their preparation methods, electrodes and their applications. The polyester composite film of this application comprises: a polyester substrate layer and a first surface layer and a second surface layer respectively disposed on opposite sides of the polyester substrate layer; the polyester substrate layer comprises, by weight, 90 to 99 parts of polyester material and 1 to 10 parts of photo-straining material; the first and second surface layers comprise polyethylene terephthalate polymers; the transmittance of the first surface layer, the second surface layer, and the polyester material is independently 92% to 99%; the photo-straining material comprises one or more of barium titanate ceramics, lead zirconate titanate ceramics, PI / CNTs photosensitive composite materials, PEEK / anthraquinone photosensitive composite materials, MIL-101 chromium metal-organic frameworks, and UiO-66-NH2 / ZnO composite materials. The polyester composite film can easily break under high-destructive external forces such as battery breakdown and battery collision, effectively suppressing thermal runaway.

The present application relates to a kind of polyethylene terephthalate-2,5-furandicarboxylic acid glycol copolyester foamed material and its preparation method, the preparation method includes the following steps: polyethylene terephthalate-2,5-furandicarboxylic acid glycol copolyester material is heat pressed, and the preform of molten state is obtained;The preform of molten state is treated with melt isothermal crystallization and quenching, and sheet material is obtained;Sheet material is treated with foaming, and polyethylene terephthalate-2,5-furandicarboxylic acid glycol copolyester foamed material is obtained.The present application uses melt isothermal crystallization treatment, can improve the melt strength in the foaming process of polyethylene terephthalate-2,5-furandicarboxylic acid glycol copolyester, strengthens its foaming performance, simultaneously can also be realized by strengthening bubble nucleation and controlling bubble growth to adjust the bubble morphology of foamed material, so polyethylene terephthalate-2,5-furandicarboxylic acid glycol copolyester foamed material with uniform bubble size and controllable foaming ratio can be obtained.

The present application relates to polybutylene terephthalate (PBT) material toothbrush filament technical field, specifically relates to a kind of multifilament version anti-lodging PBT monofilament and preparation method thereof;The preparation method is realized with the basic concept of multifilament to realize the basic form of monofilament, in the drawing process, every three monofilaments are gathered into a multifilament, in the subsequent water cooling, oiling etc. Process path, with the mode of multifilament, drafting, winding forming are completed.In the condition that monofilament specification remains unchanged, corresponding design is carried out to production process, and the quality indexes such as breaking strength, breaking strength variation coefficient, breaking elongation, breaking elongation variation coefficient of monofilament are controlled.In the realization equipment efficiency is improved three times target, product quality is upgraded, and the anti-lodging performance of PBT monofilament is improved.

The present invention relates to novel carbodiimides, to a process for their production, and to the use of the novel carbodiimides in ester-based polyols, in polyethylene terephthalate (PET), in polybutylene terephthalate (PBT), in polytrimethylene terephthalate (PTT), in copolyesters, in thermoplastic polyester elastomers (TPE E), in ethylene vinyl acetate (EVA), in polylactic acid (PLA) and / or in PLA derivatives, in polybutylene adipate terephthalate (PBAT), in polybutylene succinate (PBS), in polyhydroxyalkanoates (PHA), in blends, in triglycerides, in thermoplastic polyurethanes, in polyurethane elastomers, in PU adhesives, in PU casting resins, for PU coatings or in PU foams as stabilizers.

The invention provides a metal salt modified thermoplastic starch filled PBAT-based composite material as well as a preparation method and application thereof. The plastic film is prepared from the following components in parts by weight: 25-35 parts of thermoplastic starch, 60-70 parts of poly (butylene terephthalate)-adipate, 1-10 parts of polylactic acid, 0.1-1 part of an antioxidant, 0.1-1 part of an anti-hydrolysis agent and 0.1-1 part of a dispersing agent. 0.1-1 part by weight of an anti-blocking agent and the like are added into a high-speed mixer step by step according to a particle-liquid-powder sequence to be mixed; and extruding through a double-screw extruder, air-cooling and pelletizing to obtain the PBAT-based composite material. The metal ions and the starch hydroxyl form a coordination effect, so that the mechanical property of the PBAT-based composite material is remarkably improved, and the cost is reduced while the mechanical property of a pure PBAT material is reserved. In addition, the waistcoat type non-food contact biodegradable shopping bag made of the PBAT-based composite material can bear the weight of 5 kg, and the degradation performance meets the requirements of GB / T 38082-2019.

Depolymerization of polyalkylene terephthalate resin using Alcosilis, providing a superior depolymerization method. [Solution] The method for depolymerizing a polyalkylene terephthalate resin according to the present disclosure is a method for depolymerizing a polyalkylene terephthalate resin by alcoholization of the polyalkylene terephthalate resin, wherein the polyalkylene terephthalate resin includes a polybutylene terephthalate resin, and the alcohol used for alcoholization contains tetrahydrofuran in a proportion of more than 0 ppm by mass and 100,000 ppm or less by mass.

A second aspect relates to a polyalkylene terephthalate polymer obtained or obtainable from the method of the first aspect. A third aspect relates to the use of the polyalkylene terephthalate polymer of the second aspect for textile, fiber, packaging, plastic, automotive, and electronic applications. A fourth aspect relates to a method for producing products, comprising (I) providing a polyalkylene terephthalate polymer of the second aspect, and (II) producing textiles, fibers, packaging, plastics, automotive parts, and electronic parts from the polyalkylene terephthalate polymer provided in (I). A fifth aspect relates to a method comprising a further step of converting a again obtained polyalkylene terephthalate polymer obtained by the method of the first aspect to obtain a polymer product. A sixth aspect relates to a method comprising a further step of converting a residue obtained or obtainable from the method of the first aspect, and / or converting an elastic fiber residue obtained or obtainable from the method of the first aspect to obtain one or more monomers, polymers, or polymer products.

The invention relates to the technical field of biodegradable materials, in particular to a high-transparency ultralow-haze PBAT-based flexible film and a preparation method and application thereof, and the high-transparency ultralow-haze PBAT-based flexible film is composed of poly (butylene adipate-co-butylene terephthalate), poly (butylene succinate-co-butylene terephthalate), an antioxidant, an anti-hydrolysis agent, an anti-blocking agent and a dispersing agent in parts by weight. The polyethylene terephthalate-butylene adipate is used as a main component, the polyethylene terephthalate-butylene adipate can be added as required, and a small amount of other assistants are added to guarantee the performance of the film. According to the invention, PBAT and PBST are blended to improve the optical performance of the film, casting cooling inhibits the formation of a large crystal region, and the transparency is synergistically increased; the problems of low transparency and high haze of the PBAT-based film are solved, the use requirement of the packaging field on the film material is met, and the application of the PBAT material is further widened.

A paper comprising polymeric fibers and a binder, wherein the polymeric fibers comprise first fibers and second fibers, the first fibers comprising an aramid copolymer having a structure derived from the reaction of para-oriented aromatic diamine monomer and benzimidazole monomer with a para-oriented aromatic diacid monomer, the second fibers comprising poly(para-phenylene terephthalate) homopolymer, and the binder comprising a third polymer that is either an aramid homopolymer or aramid copolymer; the paper having an ultimate tensile strength of 21 N-m / g or greater and average specific modulus of 4950 Pa-m3 / g or greater.

The application discloses a preparation method of a bifunctional modified calcium carbonate with capacity and enhancement effects, and belongs to the technical field of biodegradable materials. Firstly, 4-aminomethyl benzoic acid solution is prepared and sprayed on the surface of pretreated calcium carbonate, and high-speed heating and mixing are conducted to obtain pretreated calcium carbonate. Secondly, folic acid is reacted in a solvent to obtain an active ester solution; the active ester solution is slowly added and dropped in a high-speed mixer while stirring to conduct a reaction, and modified calcium carbonate is obtained after drying. Finally, polybutylene adipate terephthalate and the modified calcium carbonate are subjected to high-speed mixing to obtain polybutylene adipate terephthalate / folic acid-4-aminomethyl benzoic acid-calcium carbonate mixture; the mixture is melt-extruded by using a double-screw extruder to obtain bifunctional modified calcium carbonate, the tensile strength of which is increased to 30.36 Mpa, and the elongation at break is increased to 698%; the contact angle of the prepared folic acid-4-aminomethyl benzoic acid-calcium carbonate is increased to 137.5 degrees, and the activation rate is increased to 99.10%.

The invention relates to the technical field of packaging materials, and discloses a high-barrier long-acting antibacterial composite environment-friendly packaging material and a preparation method thereof, and the high-barrier long-acting antibacterial composite environment-friendly packaging material is formed by compounding an inner-layer film, a middle-layer film and a surface-layer film. The inner-layer film is prepared from low-density polyethylene, metallocene linear low-density polyethylene and the like; the middle-layer film is a reactive compatibilization layer and comprises an ethylene-vinyl alcohol copolymer, polybutylene terephthalate adipate and a styrene glycidyl methacrylate copolymer, and compatibility and toughness are improved through an in-situ reaction; a surface film is a functional layer, phytic acid and bifunctional modified montmorillonite are utilized to construct a hybrid network, and the sedum sarmentosum extract and the chitosan quaternary ammonium salt are anchored. By adopting a step-by-step film preparation and hot-pressing compounding process, the obtained material has the characteristics of high barrier, high strength and long-acting bacteriostasis, and the glue-free compounding process is environment-friendly and safe.

The present disclosure relates to a package, such as a food package, comprising a first part and a second part, the second part being sealed to the first part at a first part circumferential edge and in a circumferential attachment zone to form a sealed inner compartment, the attachment zone having a first peelable zone and a second non-peelable zone, the first part and the second part include polymeric materials, the package is a mono polyester material package, 95 wt % or more of the package is polyester material. The second part includes a laminate having an oriented Polyethylene Terephtalate (OPET) material layer and an amorphous Polyethylene Terephtalate (APET) layer, the amorphous Polyethylene Terephtalate layer facing the first part.

In a first aspect, the present invention relates to a process for recovering a polyalkylene terephthalate-based polymer from a colored polymer material comprising a polyalkylene terephthalate-based polymer. A second aspect relates to a colorant-depleted polyalkylene terephthalate-based polymer obtained or obtainable by the process of the first aspect. A third aspect relates to: the second aspect of the use of a colorant-poor polyalkylene terephthalate-based polymer for textile applications, fiber applications, packaging applications or plastic applications, preferably for the production of food packages, beverage packages, garments and footwear; and a method for preparing a textile from a polyalkylene terephthalate-based polymer of a second aspect. A fourth aspect of the invention relates to a process comprising converting a reobtained polyalkylene terephthalate-based polymer, and a fifth aspect relates to a process comprising converting a residue.

This invention relates to the field of PBAT technology and discloses a method for preparing biodegradable PBAT foam material. The invention involves adding polybutylene terephthalate (PET), functionalized polyacrylonitrile fibers, and other additives to a twin-screw extruder for co-extrusion, followed by injection molding to obtain PBAT injection molded parts. Finally, the parts are foamed, hot-pressed, and shaped to obtain the biodegradable PBAT foam material. The use of functionalized polyacrylonitrile fibers to modify PBAT demonstrates good interfacial compatibility between the two. Adding these fibers to PBAT effectively improves the tensile strength, elongation at break, and tear strength of the PBAT foam material, exhibiting better mechanical properties.

The present application relates to a kind of bracketless invisible orthodontic treatment materials, more particularly to a kind of bracketless invisible orthodontic treatment multilayer composite film and preparation method thereof.The multilayer composite film of the present application is formed by including first layer, second layer and third layer arranged from top to bottom hot pressing;First layer and third layer are thermoplastic polyurethane, and second layer is formed by polyurethane and polyethylene terephthalate glycol-1,4-cyclohexane dimethanol extrusion injection molding after blending.The present application improves the material of each layer of composite film to prepare a kind of bracketless invisible orthodontic treatment interlayer composite excellent multilayer composite film.The multilayer composite film prepared by the present application also has the advantages of high transparency, suitable correction force and low stress relaxation rate.

The application discloses a degradable plastic master batch as well as preparation and application thereof. The degradable plastic master batch comprises the following raw materials in parts by mass: 40-60 parts of polylactic acid, 30-50 parts of polybutylene adipate terephthalate, 10-20 parts of 9,9-di-n-octylfluorene copolymer, 3-9 parts of a degradation agent and 1-5 parts of a lubricant. The 9,9-di-n-octylfluorene copolymer is added into the plastic master batch with polylactic acid and polybutylene adipate terephthalate as a base body, so that the impact strength and tensile strength of the plastic master batch are effectively improved. In addition, the degradation agent can effectively degrade the 9,9-di-n-octylfluorene copolymer, and thus the plastic master batch with high impact strength and tensile strength and degradability is obtained.

The invention discloses a material for woven bags as well as a preparation method and application thereof, and relates to the technical field of processing of materials for woven bags. The woven bag material comprises a film covering material and a weaving wire material; wherein the film covering material comprises degradable resin B and a compatilizer; the degradable resin B comprises poly (butylene adipate-co-terephthalate) and polypropylene carbonate; the woven bag material prepared from the material for weaving the silk and the material for coating is low in cost, low in rigidity and good in toughness; the mechanical strength of the coated material for the woven bag is enhanced, the water resistance is improved, the service life of the material for the woven bag is prolonged, the degradation rate of the material in the using process is delayed, and closed loop of carbon circulation is effectively achieved. The preparation method of the material for the woven bag is simple to operate; the prepared material for the woven bag or the woven bag can be widely applied to the fields of agriculture, industry and logistics transportation.

The invention belongs to the technical field of polyester fibers, and particularly relates to an antibacterial polyester fiber and a preparation method thereof. The antibacterial polyester fiber comprises the following components in parts by weight: 90-100 parts of polyethylene glycol terephthalate; 8-10 parts of modified hemp fiber; 3-5 parts of a functional agent; 6-8 parts of a composite filler; 2-4 parts of a lubricant; wherein the modified hemp fiber is prepared by reacting hemp fiber with antibacterial benzotriazole silane, and the functional agent is antibacterial benzotriazole silane; according to the antibacterial polyester fiber, the modified hemp fiber and the functional agent antibacterial benzotriazole silane are added into the polyester fiber component, so that the polyester fiber is modified, the polyester fiber with excellent antibacterial performance, antibacterial durability and ultraviolet resistance is obtained, and meanwhile, the polyester fiber provided by the invention also has good breaking strength.

The present invention relates to a thermoplastic resin composition, a method for preparing the same, and a molded article comprising the same. More specifically, the present invention relates to: a thermoplastic resin composition prepared by adding a compatibilizer to a base resin comprising an ASA-based graft copolymer, an SAN-based and / or SAMMA-based resin, and a regenerated or non-regenerated polyalkylene terephthalate, and adjusting the composition ratio thereof; a method for preparing the thermoplastic resin composition; and a molded article including the thermoplastic resin composition. According to the present invention, the intrinsic mechanical properties of the ASA-based resin and the polyester resin can be maintained at a certain level or higher, and the film processability, glossiness, whiteness, weather resistance, and thermal stability can be excellent. In addition, impact resistance, film processability, low gloss characteristics, weather resistance, and thermal stability may be excellent even when the regenerated resin is included.

This invention discloses a polycarbonate polyester composition, its preparation method, and its applications, relating to the technical field of plastics. The polycarbonate polyester composition of this invention comprises the following components in parts by weight: 44-93 parts polycarbonate; 14-46 parts poly(butylene terephthalate); 0.9-12 parts toughening agent; 4-12 parts flame retardant; 0.4-3.2 parts synergistic flame retardant; and 0.09-6 parts anti-dripping agent. The flame retardant is hexaphenoxycyclotriphosphazene, and the synergistic flame retardant includes a silane coupling agent and aluminum diethylphosphonate. The mass ratio of the silane coupling agent to aluminum diethylphosphonate in the synergistic flame retardant is (0.4-2):100. The polycarbonate polyester composition of this invention features halogen-free flame retardancy, high heat resistance, and high toughness.

This invention discloses a breathable and wear-resistant casual shoe, comprising an upper and a sole. The sole comprises the following components in parts by weight: 20-30 parts polyurethane-acrylate copolymer, 6-10 parts polyoxyethylene ether, 12-20 parts styrene-butadiene rubber, 5-10 parts modified polyvinylidene fluoride, 12-18 parts modified polybutylene terephthalate-adipate, 1-3 parts zinc oxide, 1-2 parts vinyltrimethoxysilane, 8-10 parts diatomaceous earth, 4-8 parts calcium stearate, 5-8 parts vinyl silicone oil, and 10-15 parts ethylenediaminetetraacetic acid. This invention provides a breathable and wear-resistant casual shoe and its preparation method, improving the breathability of the material while also providing good wear resistance.

The application provides a kind of bio-based degradable pressure-sensitive adhesive, adhesive tape and preparation method thereof;The bio-based degradable adhesive tape includes degradable adhesive layer and degradable substrate layer;The degradable substrate layer is PLA / PBAT composite film;The degradable adhesive layer is bio-based degradable pressure-sensitive adhesive;The bio-based degradable pressure-sensitive adhesive includes 40-65 parts by weight of aliphatic polyester elastomer modified particles, 10-25 parts by weight of degradable tackifying resin, 3-8 parts by weight of vegetable oil plasticizer, 0.5-2 parts by weight of crosslinking agent, 0.1-0.5 parts by weight of antioxidant.The aliphatic polyester elastomer modified particles are prepared by blending, extruding and granulating polybutylene terephthalate adipate, polycaprolactone and chain extender.The application improves the degradation rate while maintaining high peel strength and tack force, meeting the needs of sealing packaging.

The present application relates to a drawing process of polybutylene terephthalate (PBT) material, and particularly relates to a flexible and lodging-resistant PBT toothbrush filament and a preparation method thereof, which comprises the following steps: heating and melting polybutylene terephthalate material particles after drying treatment and vacuum packaging in a screw extruder to obtain molten polybutylene terephthalate; filtering through a melt filtration system; extruding through a spinneret of the screw extruder to form viscous flow state primary fibers; introducing the primary fibers into a cooling water bath to obtain viscoelastic state primary fiber filaments; and performing a series of high-drawing processing on the primary fiber filaments so that macromolecular chains are fully ordered to become glassy PBT toothbrush filaments. During the process, the production process is designed to control the breaking strength, breaking strength variation coefficient, breaking elongation, breaking elongation variation coefficient, filament bending recovery rate and the like of the filaments, so as to obtain a flexible and lodging-resistant PBT toothbrush filament and a preparation method thereof.

The present application relates to the technical field of polyester composite material, in particular to a reinforced flame-retardant polyester composite material for baking integrated machine shell and a preparation method thereof, the composite material takes polybutylene terephthalate and poly(1,4-cyclohexylenedimethylene terephthalate) as main raw materials, and higher heat distortion temperature, heat resistance and high strength are obtained by the cooperation of the two, the polybutylene terephthalate has better fatigue resistance and size stability, and smaller creep; the grafting modification thermoplastic polyester elastomer is added, the special heat-sensitive hydrophobicity and the toughening property of the thermoplastic polyester elastomer are utilized, and the toughening agent and the antioxidant are synergistically used to improve the hydrolysis resistance, high-temperature and high-humidity weather resistance, high-low temperature impact toughness and low shrinkage of the polyester composite material; the synergistic flame-retardant effect of the added bromine-based flame retardant and halogen-free flame retardant can meet the flame-retardant requirements of the material; the glass fiber has the effects of hydrolysis resistance and low warping, and the low shrinkage can promote the structure of the product to be flat, and the polyester composite material is particularly suitable for producing baking integrated machine shell.

This utility model relates to the field of electronic device input device technology, and discloses a shaft structure for reducing bottoming noise of the shaft core. The structure includes a lower shell, an upper shell, and a shaft core. The lower shell engages with the upper shell, and the shaft core is installed between the two shells. All three shells are made of environmentally friendly materials, such as polyethylene terephthalate (PET) or any other environmentally friendly material suitable for shaft construction that does not affect durability. The closed installation of the lower and upper shells allows the shaft core to be positioned inside the shells and move stably up and down. A sleeve is fixed inside the lower shell, and a slot is formed at the bottom of the lower shell, communicating with the sleeve. The upper shell is mounted on the lower shell. By creating a slot at the bottom of the lower shell, which is vertically opposite to a magnet, when the shaft core is subjected to downward force and displacement, the magnet at the bottom of the shaft passes through the slot and does not rigidly collide with the lower shell, effectively reducing the noise generated by the magnet colliding with the lower shell.

Provided is a biodegradable three-dimensional network structure having excellent compression recoverability and repeated compression characteristics after thermal compression at a use ambient temperature. A three-dimensional network structure having a three-dimensional random ring-bonded structure, the three-dimensional network structure being characterized in that the continuous lines are formed from a thermoplastic resin composition, and the thermoplastic resin composition contains 70 mass% or more of a poly (butylene adipate-co-terephthalic acid) resin, and the thermoplastic resin composition contains a polybutylene adipate-co-terephthalic acid) resin, the polybutylene adipate-co-terephthalic acid resin, and the polybutylene adipate-co-terephthalic acid resin. In a differential scanning calorimetry curve of the continuous lines measured using a differential scanning calorimeter, the enthalpy of an endothermic peak having a minimum value in the range of 30 DEG C to 70 DEG C is 2.5 J / g or less, and the average fiber diameter of the continuous lines is 0.1 mm to 3.0 mm (inclusive). The average fiber diameter of the surface layer part of the three-dimensional network structure is 1.05 times or more of the average fiber diameter of the inner layer part, the apparent density of the three-dimensional network structure is 0.01-0.20 g / cm3, the residual strain after repeated compression at a constant load of 750 N is 15% or less, and the hardness retention rate at 40% compression after repeated compression at a constant load of 750 N is 45% or more.