JP3314839B2 - Heat-adhesive network structure and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a futon, a furniture, a bed,
The present invention relates to a heat-adhesive net-like structure having excellent cushioning properties and heat resistance and durability suitable for a vehicle cushion material, a heat insulating material, and the like, and easily heat-bondable, and a method for producing the same.

[0002]

2. Description of the Related Art At present, urethane foam, non-elastic crimped fiber-filled cotton, and resin cotton and hard cotton to which non-elastic crimped fibers are bonded are used as cushioning materials for futons, furniture, beds, trains, automobiles, and the like. Have been.

[0003] However, foamed-crosslinked urethane has good durability as a cushioning material, but is inferior in moisture permeation and water permeability and has heat storage properties, so that it is easy to humid. In addition, the damage to the incinerator is large, and the cost for removing toxic gas is high.
For this reason, landfills have been increased, but there is a problem in that it is difficult to stabilize the ground, so that landfill locations are limited and costs increase. Further, although the processability is excellent, there is a problem of pollution of chemicals used during the production. In addition, in the case of the cotton filled with thermoplastic polyester fiber, since the space between the fibers is not fixed, the shape at the time of use collapses, the fiber moves, and the crimp set causes a decrease in bulkiness and a decrease in elasticity. become.

Japanese Patent Application Laid-Open Publication No. Sho 6 (1994) discloses a resin cotton in which polyester fibers are bonded with an adhesive, for example, a rubber using an adhesive as a rubber.
Nos. 0-11352, JP-A-61-141388 and JP-A-61-141391. Further, JP-A-61-1377 discloses a method using a crosslinkable urethane.
No. 32 publication. These cushioning materials are inferior in durability, are not thermoplastic, cannot be recycled because they are not a single composition, and have problems such as complicated workability and pollution of chemicals used during production. .

[0005] Polyester hard cotton, for example, JP-A-58-3
JP-A No. 1150, JP-A-2-154050, JP-A-3-220354, etc., are disclosed in Japanese Patent Application Laid-Open No. Sho 58-58, because the adhesive component of the heat-bonding fiber used is a brittle amorphous polymer. -136828, JP-A-3-
There is a problem that the adhesive portion is brittle and the durability is poor such that the adhesive portion is easily broken during use and the form and elasticity are reduced. As an improved method, a method of performing confounding treatment has been proposed in Japanese Patent Application Laid-Open No. 4-245965, but there is a problem that the brittleness of the bonded portion is not solved and the elasticity is greatly reduced. In addition, there is also complexity in processing. Further, there is a problem that the bonded portion is hardly deformed and it is difficult to provide soft cushioning. For this reason, the adhesive is soft and the polyester elastomer recovers even if deformed to some extent.
Japanese Patent Application Laid-Open No. 4-240219 discloses a thermal bonding fiber using an inelastic polyester as a core component, and WO-91 / 19032, Japanese Patent Application Laid-Open No. 5-156561 discloses a cushioning material using the fiber. It has been proposed in, for example, JP-A-5-163654. When the adhesive component used in this fiber structure is a soft segment of polyester elastomer, the content of polyalkylene glycol is 30 to 50.
5% by weight of terephthalic acid in the acid component of the hard segment
It contains 0 to 80 mol%, and contains isophthalic acid as another acid component composition to increase the amorphousness, and has a melting point of 180%.
℃ or lower and low melt viscosity to improve the formation of the heat-bonded part to form an amoeboid bonded part, but plastic deformation is easy, and the core component is inelastic polyester, so plastic deformation especially under heating And there is a problem that heat resistance and compression resistance decrease. In addition, this fiber is the Japanese Patent Publication No. 60-1
Since the fibers are considered to be the same as those described in Japanese Patent No. 404, it cannot be said that the prior art is improved.

A thermoplastic olefin network used for civil engineering is disclosed in JP-A-47-44839. However, unlike a cushion made of fine fibers, the surface is uneven and the touch is poor, and since the material is an olefin, the heat resistance and durability are extremely poor and cannot be used as a cushion material. In Japanese Patent Publication No. 3-17666, there is a method in which discharge filaments having different fineness are fused to each other to form a molding, but this is a net-like structure not suitable for a cushion material. Japanese Patent Publication No. 3-55583 discloses a method in which only a very small surface is thinned by a thinning device such as a rotating body before cooling. In this method, the surface cannot be flattened, and a thick and thin linear layer cannot be formed. Therefore, the cushioning material does not provide a comfortable sitting comfort. JP-A-1-207
Japanese Patent Publication No. 462 discloses a floor mat made of vinyl chloride, which is not preferable as a cushioning material because of its poor compression recovery at room temperature and extremely poor heat resistance. There is no problem that the reticulated body has self-heat adhesion to the nonwoven fabric or the side fabric, and the high-order processing uses an adhesive or impregnated with a foam, so the processing cost is high. .

[0007]

SUMMARY OF THE INVENTION In order to solve the above problems,
Provided is a heat-adhesive network structure made of a thermoplastic elastic resin having a self-heat-adhesive property, which is suitable for a heat-resistant and cushioning-resistant cushion material having excellent heat resistance and excellent high-order workability, and a method for producing the same. With the goal.

[0008]

Means for solving the above-mentioned problems, that is, the present invention comprises a high melting point and a low melting point thermoplastic elastic resin, and has a melting point of 10 ° C. higher than the melting point of the high melting point thermoplastic elastic resin.
A network structure made of a low melting point thermoplastic elastic resin having a low melting point forms a thermal bonding layer, a network structure made of a high melting point thermoplastic elastic resin forms a basic layer, and both layers are three-dimensional landers.
A heat-adhesive network structure that is fused and integrated at the time of forming a loop, and the network structure winds a continuous filament to form a large number of loops, and brings the respective loops into contact with each other to form a contact portion. mostly fused, a three-dimensional random loop structure in which the shape-keeping a constant width and thickness, one side or both sides of the heat-adhesive net structure is formed by a substantially heat-bonding layer which is flattened in , The thickness of the heat bonding layer is 1 mm or more,
A heat-adhesive network characterized by being 0 mm or less, a heat-adhesive layer made of a low-melting-point thermoplastic elastic resin is formed on one or both surfaces of the net-like structure, and the thermoplastic adhesive is formed on portions other than the heat-adhesive layer. At least 10 ° C above the melting point of the elastic resin
From a nozzle distributed so that a basic layer made of a thermoplastic elastic resin having a higher melting point is formed, the resin in a molten state is discharged downward at a temperature 10 to 120 ° C. higher than the melting point of each resin, A large number of loops are formed in a molten state, and the respective loops are brought into contact with each other and fused to form a three-dimensional random loop structure having a constant width and thickness, and are sandwiched by a take-off device, and are substantially formed in a plane. Is flattened and cooled in a cooling tank, and the heat bonding layer and the base layer are separated from each other .
It is a preparation of heat-adhesive net structure, characterized in that fusing together of.

The thermoplastic elastic resin in the present invention is obtained by block copolymerizing a soft segment such as a polyether-based glycol, a polyester-based glycol, and a polycarbonate-based glycol having a molecular weight of 300 to 5,000. Polyester-based elastomer, polyamide-based elastomer,
Polyurethane-based elastomers and the like can be mentioned. By using a thermoplastic elastic resin, regeneration becomes possible by re-melting, so that recycling becomes easy. For example, as a polyester-based elastomer, a polyester ether block copolymer having a thermoplastic polyester as a hard segment and a polyalkylenediol as a soft segment, or a polyester ester having an aliphatic polyester as a soft segment A block copolymer can be exemplified. More specific examples of polyester ether block copolymers include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, naphthalene 2.6 dicarboxylic acid, naphthalene 2.7 dicarboxylic acid, and diphenyl 4.4 4 'dicarboxylic acid. Alicyclic dicarboxylic acids such as 1.4 cyclohexanedicarboxylic acid, aliphatic dicarboxylic acids such as succinic acid, adipic acid, sebacic acid dimer acid, and at least one dicarboxylic acid selected from ester-forming derivatives thereof; Seeds, 1,4-butanediol, ethylene glyco-
, Trimethylene glycol, tetramethylene glycol
Alicyclic diols such as aliphatic diols such as toluene, pentamethylene glycol and hexamethylene glycol, and 1.1 cyclohexane dimethanol, and 1.4 cyclohexane dimethanol, and the like. At least one diol component selected from ester-forming derivatives and the like; and polyethylene glycol having an average molecular weight of about 300 to 5,000.
A triblock copolymer composed of at least one of polyalkylenediols such as ethylene glycol, polypropylene glycol, polytetramethylene glycol, and ethylene oxide-propylene oxide copolymer. The polyester ester block copolymer is a ternary block copolymer composed of at least one of each of the above dicarboxylic acids, diols, and polyester diols such as polylactone having an average molecular weight of about 300 to 5,000. .
In consideration of thermal adhesion, hydrolysis resistance, stretchability, heat resistance, etc., terephthalic acid or naphthalene 2.6 dicarboxylic acid as a dicarboxylic acid, 1.4 butanediol as a diol component, poly As the alkylenediol, a triblock copolymer of polytetramethylene glycol or a terpolymer of polyester is particularly preferable. In a special case,
Those into which polysiloxane-based soft segments are introduced can also be used. The thermoplastic elastomer resin of the present invention also includes those obtained by blending a non-elastomer component with the above-mentioned elastomer and copolymerizing the same. In addition, durability can be improved by adding an antioxidant, a light stabilizer, or the like, if necessary. The melting point of the thermoplastic high-melting point elastic resin (abbreviated as high-melting point elastic resin) of the present invention is preferably 140 ° C. or higher, which can maintain the heat resistance and durability. preferable. Unless the melting point of the thermoplastic low melting point elastic resin (abbreviated as low melting point elastic resin) serving as the heat bonding component is not lowered by at least 10 ° C. or more, the network structure made of the high melting point elastic resin may be softened or deformed during heat bonding. If there is no difference, it is not preferable because it melts and loses the network structure. When the difference in melting point from the high melting point elastic resin is significantly lower than 100 ° C., when the reticulated body is manufactured at the same melting temperature, if the residence time is long, the thermal decomposition of the low melting point elastic resin becomes remarkable and the molecular weight required for the adhesive function is reduced. Since retention is no longer possible, the residence time at high temperatures must be significantly reduced. The melting point difference of the low melting point elastic resin for maintaining the network structure composed of the high melting point elastic resin needs to be 10 ° C or more, preferably 15 ° C or more and 80 ° C or less, more preferably 20 ° C or more and 50 ° C or less. . Further, the temperature at the time of heat bonding is preferably lower from the viewpoint of productivity, but is preferably higher to maintain heat resistance. Since the heat resistance required for a cushioning material for automobiles requiring heat resistance is 70 ° C. or higher, the melting point of the low melting point elastic resin is preferably 80 ° C. to 220 ° C., more preferably 120 ° C. to 200 ° C.
It is as follows.

[0010] The filaments constituting the network structure of the present invention preferably have an endothermic peak below the melting point in the melting curve measured by a differential scanning calorimeter. Those having an endothermic peak below the melting point have remarkably good elongation recoverability at room temperature and high temperature, so that the heat resistance and sag resistance of the network structure are remarkably improved as compared with those having no endothermic peak. For example,
As a preferred polyester-based elastomer of the present invention,
An acid component containing at least 90 mol% of terephthalic acid or naphthalene 2.6 dicarboxylic acid, more preferably at least 95 mol%, particularly preferably 100 mol%, of terephthalic acid or naphthalene 2.6 dicarboxylic acid. After transesterification of the glycol component, polymerization is carried out to a required degree of polymerization, and then, as polyalkylenediol, polytetramethylene glycol having an average molecular weight of preferably 500 or more and 5000 or less, particularly preferably 1000 or more and 3000 or less. 15 to 70% by weight, more preferably 30 to 60% by weight,
If the content of terephthalic acid or naphthalene 2,6-dicarboxylic acid is large, the crystallinity of the hard segment is improved, the plastic segment is hardly deformed, and the heat resistance and set resistance are improved. When the unring treatment is performed at a temperature lower by at least 10 ° C., the heat resistance and set resistance are further improved.
Annealing after imparting compressive strain further improves heat resistance and sag resistance. When a melting curve of a line of the network structure thus treated is measured by a differential scanning calorimeter (DSC), an endothermic peak is more clearly exhibited at a temperature equal to or higher than the glass transition temperature of the hard segment and equal to or lower than the melting point. . When annealing is not performed, the endothermic peak is kept below the melting point.
Does not develop By analogy with this, it is considered that the hard segments are rearranged by the unring, pseudo-crystallization-like cross-linking points are formed, and the heat resistance is improved. (This process is defined as a pseudo-crystallization process.)

[0011] The reticulated structure of the present invention is characterized in that a wire made of a thermoplastic elastic resin is meandered, and the wires are brought into contact with each other;
The contact portions are fused to form a three-dimensional network structure. As a result, even if a large deformation is given by a very large stress, the entire fusion-integrated three-dimensional network structure is deformed to absorb the stress, and when the stress is released, the rubber elasticity of the elastic resin is developed. The structure can be restored to its original form. In a net-like structure constituted by a filament made of a known inelastic resin, plastic deformation occurs and such recovery does not occur, so that heat resistance and durability are inferior. If not fused, the shape cannot be maintained,
Since the structure is not integrally deformed, a fatigue phenomenon due to stress concentration occurs and durability is deteriorated, and at the same time, the form is undesirably deformed. A more preferable degree of fusion in the present invention is a state in which most of the portions in contact with the filaments are fused, and most preferably a state in which all the contact portions are fused.

The reticulated structure made of the thermoplastic elastic resin of the present invention is such that the filaments constituting one or both surfaces of the reticulated structure have a melting point at least 10 ° C. higher than the melting point of the refractory elastic resin filaments in contact with the surface. By forming a layer made of a low-melting-point elastic resin having a thickness of 1 mm or more and 10 mm or less, the low-melting-point elastic resin becomes a heat-adhesive component, and enables heat-adhesion processing.
If you want to bond nets, non-woven fabrics, knitted fabrics, hard cotton, films, foams, metals, powders, fibrous materials, etc. on one side, form a layer of the heat-adhesive component on one side, and both sides on both sides. With the configuration in which the heat bonding component is formed, a new molded body can be obtained by heat bonding without applying an adhesive or adding an adhesive layer. If the thickness is less than 1 mm, the adhesion is insufficient, and if it exceeds 10 mm, the thickness is significantly reduced during thermal bonding, which is not preferable. The preferred thickness of the present invention is between 2 mm and 8 mm, more preferably between 2.5 mm and 7.5 mm. As described above, the difference in melting point between the low melting point elastic resin and the high melting point elastic resin is 10 ° C.
Above, preferably 15 ° C. or more and 80 ° C. or less, more preferably 20 ° C. or more and 50 ° C. or less. In this range, in addition to retaining the network structure made of the high-melting point elastic resin, the heat-adhesive network structure of the present invention, which has not been subjected to the pseudo-crystallization treatment, is heated and heat-bonded using hot air or the like. When a new structure is molded, the heat bonding temperature is higher than the melting point of the low melting point elastic resin and at least 10 ° C. lower than the melting point of the high melting point elastic resin. The effect of pseudo crystallization can also be obtained. By performing the heat bonding process under these conditions, a new structure is formed by heat bonding with a high degree of heat resistance higher than that of the high melting point elastic resin in the original heat bonding network structure. It has features that can be added when performing After the thermal bonding, the new structure is further annealed at a temperature lower than the melting point of the low melting point elastic resin by 10 ° C. or more, so that the stretch recovery of the adhesive layer is significantly improved. Even if the structure is deformed greatly by external force, the adhesive layer and the net-like structure are elastic resin, so the whole structure can easily follow the deformation and absorb the deformation distortion, and if the external force is released, the elastic resin Because the rubber elasticity is developed and the structure can be restored to the original form, a new molded article obtained by using the heat-adhesive network structure of the present invention can be subjected to a high degree of sag resistance at room temperature and high temperature. Properties can be imparted. On the other hand, only the adhesive surface is, for example, far infrared rays or a heating roller.
In the case of heating and heat-bonding using a method such as the above, it is preferable to use a pseudo-crystallized network structure made of a high melting point elastic resin. Also in this case, it is preferable to further anneal the new structure at a temperature lower than the melting point of the low melting point elastic resin by 10 ° C. or more after the thermal bonding, for the above-described reason. Only when the surface of the heat-adhesive component is heated and heat-adhesion is performed using a method that can maintain the network structure of the adhesive component layer, if the heat-adhesive component layer is slightly thickened up to a thickness of 10 mm or less, a cushion material can be used. As a slightly soft layer, it can also have the function of a layer (surface layer) that gives a comfortable buttocks touch by moderate sinking and makes the buttocks pressure distribution evenly distributed. In the present invention, a configuration in which a thermal adhesive layer is provided on the surface layer can also be employed. When used as a cushion material, the function of the cushion layer is a layer (basic layer) that is responsible for vibration absorption and body shape retention,
It is necessary to improve the sitting comfort by integrally deforming and absorbing stress and vibration by integrating the surface layer. Further, since the surface layer and the basic layer are fused and integrated, the external force can be deformed and absorbed by the entire structure, thereby preventing the sag resistance and the heat resistance durability from lowering. If the surface layer and the base layer are not melt-bonded, it is not preferable because the surface layer is easily removed selectively. According to the present invention, the basic layer and the surface layer can be formed into a network structure in which each layer is arbitrarily formed of a line made of a thermoplastic elastic resin different from each other according to the required functions, and is fused and integrated. A preferred configuration exhibiting the above-mentioned function is that the surface layer or the layer also serving as a heat bonding layer with a thickness of 10 mm or less has a soft (slightly low modulus) and good recoverability, for example, 50% to 70% softness. From a thermoplastic elastic resin containing segments (in the present invention, the layer that also serves as the heat bonding layer is a low melting point elastic resin, and when the heat bonding layer is provided on the surface layer, the surface layer becomes a high melting point elastic resin) For example, it can be formed with a linear line. The base layer contains a hard (slightly high modulus) recoverable, for example, 20% to 50% soft segment, and the hard segment is a thermoplastic elastic resin containing rigid naphthalate (in the present invention). (High melting point elastic resin), and the surface layer and the basic layer are not a single layer but a multilayer, so that fine control of cushioning property and uniform dispersion of compressive stress can be easily performed. Forming a surface layer or a basic layer in which two or more linear layers of a thermoplastic elastic resin of a soft component and a thermoplastic resin of a hard component are preferably integrated, and more preferably three or more. Is a more preferred example of the present invention. In a network structure consisting of a single component that also serves as a heat bonding component, if the surface layer function is given, it is too soft and loses the function of the base layer, and if the function of the base layer is given, it becomes hard and the function of the surface layer becomes hard. As a result, the functions of the surface layer and the basic layer cannot be simultaneously satisfied. On the other hand, the surface opposite to the surface layer can also have a heat bonding layer in the present invention. For this purpose, a reinforcing material having a high modulus and good shape retention is thermally bonded to the surface of the cushion material in contact with the frame, so that the vibration and repulsive stress received from the frame surface are uniformly transmitted to the cushion layer. The whole unit is deformed so that it can be converted into energy, so that the sitting comfort can be improved and the durability of the cushion can be improved. It is preferable to bond the reinforcing material having the vibration absorbing layer by heat, because the riding comfort is further improved. In order to impart a function, an optimum combination with the fineness and density of each layer can be arbitrarily selected in consideration of the linear component.

The thickness and cross-sectional shape of the filaments constituting the net-like structure of the present invention are not particularly limited. However, if it is too thin, it becomes too soft and the body shape is maintained and a suitable anti-compression resilience is reduced. The thickness of the line forming the network structure made of the melting point elastic resin is preferably 0.001 to 10 mm, more preferably 0.01 to 5 mm. If the low melting point elastic resin forming the adhesive layer is too thick, it is difficult to heat and melt, and the number of bonding points on the bonding surface is reduced, so that it is preferably 5 mm or less,
More preferably, it is 0.001 mm to 2 mm. The cross-sectional shape of the filament constituting the network structure made of the high-melting point elastic resin of the present invention is particularly preferable because it is possible to impart a compressive property and a bulky property to a hollow cross section or an irregular cross section. The anti-compression property is adjusted by the modulus of the thermoplastic elastic resin to be used.The hollow modulus and the degree of irregularity can be increased in a soft thermoplastic elastic resin, and the gradient of the initial compressive stress can be adjusted. By lowering the ratio and the degree of irregularity, or by reducing the secondary moment of the cross section as a round cross section, it is possible to impart good compression resistance to the sitting comfort. As another effect of hollow cross section and irregular cross section, by increasing the hollow ratio and degree of irregularity, when the same anti-compression property is imparted, the apparent density can be reduced, so that it is possible to reduce the weight, making it possible to reduce When used, energy saving can be achieved.
Handleability when lifting and lowering is improved. It is preferable that the cross-sectional shape of the low-melting point elastic resin forming the adhesive layer is also an irregular cross-section, because the bonding strength can be improved by increasing the bonding area.

Although the apparent density of the net-like structure of the present invention is not particularly limited, the net-like structure made of a high-melting point elastic resin easily exhibits a function as a cushion.
005g / cm ³ or more 0.20 g / cm ³ or less,
More preferably, 0.01 g / cm ³ or more and 0.10 g / cm ³
It is as follows. The apparent density of the adhesive layer composed of the low melting point elastic resin is a net, a nonwoven fabric, a knitted fabric,
Some migration at the interface between the adhesive layer and the layer to be thermally bonded, such as hard cotton, film, foam, metal, powder, or fibrous material, to obtain a new molded product that is firmly thermally bonded. It is preferably 0.01 g / cm ³ or more and 0.20 g / cm ³ or less. When the network structure made of the high melting point elastic resin is integrated with two or more types of layers, the apparent density of each layer can be changed to give preferable characteristics.
For example, the apparent density of the surface layer is slightly increased to 0.04 to 0.06 g / cm ³ by using a thermoplastic elastic resin having a relatively low modulus and a good recoverability for the surface layer and increasing the number of filaments. The stress applied to one of the filaments is reduced to improve the dispersion of the stress, and the cushion layer is made of a thermoplastic elastic resin filament having a somewhat high modulus of 0.04 to 0.06 g / cm ^3.
With a medium density, the cushioning to support the buttocks is improved, and the vibration and repulsive stress received from the frame surface are evenly transmitted to the cushion layer. -It can be converted to improve sitting comfort and improve the durability of the cushion. In addition, in order to increase the thickness and the tension of the side of the seat, the fineness can be made slightly thinner partially to increase the density. For each layer composed of the filaments having different finenesses as described above, a preferable density and fineness can be arbitrarily selected in consideration of the purpose thereof, including the combination with the characteristics of the thermoplastic elastic resin. The thickness of each layer of the network structure is not particularly limited,
The mesh structure made of the high melting point elastic resin is preferably 3 mm or more in which the function as a cushion body is easily developed. The thickness of the adhesive layer composed of the low melting point elastic resin is preferably 2 mm or more and 10 mm or less in order to have an adhesive function and reduce the thickness change during molding. The size of the random loop can be arbitrarily selected according to the intended use, but the diameter is preferably 1 to 5 mm, particularly preferably 2 to 15 mm.

When a line made of a thermoplastic elastic resin having a meandering surface on the surface of the reticulated structure is made a horizontal line in the thickness direction, the angle from the line is bent by 45 ° or more, and the surface is substantially flattened. Thus, it is a preferred embodiment of the present invention that most of the contact portions are fused. In the present invention, one or both of the surfaces of the network structure is formed of a heat bonding layer made of a low melting point elastic resin, and the heat bonding surface is substantially flattened, so that the network, nonwoven fabric, knitted fabric, hard Since the area of contact with the surface of the object to be heated such as cotton, film, foam, metal, etc. can be increased, the area of thermal adhesion can be increased, and a new molded article that is strongly thermally bonded can be obtained. This is because the point of contact between the reticular structure layer made of a high melting point elastic resin and the line of the heat bonding layer is greatly increased to form a bonding point. Is deformed as a whole, the entire internal structure is also deformed to absorb the stress, and when the stress is released, the rubber elasticity of the elastic resin is developed, and the structure can recover to its original form, It is possible to obtain a molded article having excellent sitting comfort and excellent cushion durability. The same effect is exhibited when one surface is made of a high melting point elastic resin. When not substantially flattened, the contact area between the heat-bonded surface and the reticulated structure layer made of the high-melting-point elastic resin is reduced on the uneven bonding surface, so that the area of the thermal bonding point is also reduced, and the external force is reduced. This is not preferable because the transmission is concentrated at the heat bonding point and fatigue due to stress concentration occurs to reduce sag resistance. Furthermore, since the adhesion is insufficient, problems such as peeling may occur.
In the case of an inelastic resin, even if the surface is substantially flat, the stress is directly concentrated on the bonding point, causing structural destruction and making recovery difficult.

Next, the production method of the present invention will be described. The network structure of the present invention is formed such that a layer of a low-melting thermoplastic elastic resin is formed on one or both sides of the network structure, and a layer of a high-melting thermoplastic elastic resin is formed on other portions. From the dispensed nozzles, make each resin 10 ° C or more from the melting point, 12
Discharged below the nozzle at a melting temperature of 0 ° C or less, and the discharge lines in the molten state are meandered and brought into contact with each other to fuse most of the contact portions to form a three-dimensional structure while taking off. This is a method for producing a heat-adhesive network structure, in which the network is sandwiched between devices and then cooled in a cooling bath to form a network in one step. In order to obtain the network structure of the present invention, at least a two-component extruder, preferably a three-component extruder, is used to form a low-melting thermoplastic elastic resin serving as a heat bonding component and a high-melting thermoplastic elastic resin serving as a cushion body. Each single component is melted and the low melting point elastic resin is distributed on the back of the nozzle so as to constitute one or both sides of the net-like structure, and the high melting point thermoplastic elastic resin is distributed to the other parts and is distributed from the nozzle orifice. Discharge. In a preferred embodiment of the present invention, for example, in the case of a circular cross-section orifice in which the effective width in the longitudinal direction is 50 mm, the pitch between the holes in the row in the width direction of the nozzle is constant at 10 mm, and the pitch between the rows is constant at 5 mm, In the case where the low melting point elastic resin forming
In the case of disposing on the second to second rows, or on both sides, the first and eleventh rows or the first to second and eleventh rows or the tenth and eleventh rows are distributed to the thickness of the heat-adhesive component layer. And the high-melting point elastic resin is distributed to other rows, preferably at the same melting temperature of 10 ° C. or more and 120 ° C. or less from the melting point of each component. Is preferably 2.5 g / min for the heat bonding layer and 2 g / min for the cushion, and preferably each component is The melted elastic resin is sent to the nozzle by a gear pump and discharged downward from each orifice. In a more preferred embodiment of the present invention, when the number of components is increased by the heat bonding layer, for example, the pitch between the holes in the first to second rows is 5 mm, and the pitch between the holes in the tenth and eleventh rows is 6. If the total discharge amount of each component is changed to 67 mm and the same amount is discharged, the apparent density of the heat bonding layer becomes 0.06.
08 g / cm ³ , cushion-forming layer 0.0404
g / cm ³ and double the number of components without changing, and about 1.5
A dense thermal adhesive layer that is doubled can be obtained. Of course, the cushion characteristics can be optimized by changing the hole density of a specific portion of the high-melting point elastic resin layer that becomes the cushion body. In addition, if the pressure loss difference at the time of discharge is given by changing the cross-sectional area of the orifice, a principle is used in which the discharge amount at which the molten thermoplastic elastic resin is extruded at a constant pressure from the same nozzle becomes smaller as the orifice with a larger pressure loss is used. It is also possible to manufacture a net-like structure composed of filaments of different fineness within and between rows. The orifice shape of the nozzle used in the present invention may have a round cross-section, but in the present invention, the three-dimensional structure formed by the molten discharge filament is less likely to flow by forming the filament into a hollow or irregular cross-section. This is particularly preferable because the flow time at the contact point can be kept long and the adhesion point can be strengthened. In the case of heating for bonding described in Japanese Patent Application Laid-Open No. 1-2075, it is not preferable because the three-dimensional structure is easily relaxed, and it becomes difficult to form a three-dimensional structure. Next, the both sides of the molten three-dimensional structure are sandwiched by the take-off net, and the melted and twisted discharge lines on both sides are bent and deformed by 45 ° or more to flatten the surface and at the same time the discharge lines that are not bent. After the structure is formed by bonding the contact points with water, it is quenched continuously with a cooling medium (usually, it is preferable to use water at room temperature because the cooling rate can be increased and the cost is reduced). Obtain a three-dimensional three-dimensional network structure. Then, drying with water is performed. However, if a surfactant or the like is added to the cooling medium, draining or drying becomes difficult, and the thermoplastic elastic resin may swell, which is not preferable. As a preferred method of the present invention, a pseudo crystallization treatment is performed after cooling once. The pseudo-crystallization treatment temperature is at least 10 ° C. lower than the melting point (Tm) and is equal to or higher than the α dispersion rise temperature (Tαcr) of Tan δ. In this process, an endothermic peak below the melting point and not subjected to pseudo-crystallization treatment (no endothermic peak)
The heat and sag resistance is significantly improved. The preferred pseudo-crystallization temperature of the present invention is (Tαcr +
10 ° C.) to (Tm−20 ° C.) of the low melting point elastic resin. Pseudo crystallization by simple heat treatment improves heat set resistance. However, it is more preferable to perform annealing after imparting a compressive deformation of 10% or more after cooling once, since heat resistance and sag resistance are remarkably improved. In the case where a drying step is performed after cooling once, the pseudo crystallization treatment can be performed at the same time by setting the drying temperature to the annealing temperature.
Further, a pseudo crystallization treatment can be separately performed at the time of heat bonding molding or after the heat bonding molding. Next, it is cut into a desired length or shape and used as a cushion material. The desired loop diameter and wire diameter can be determined by the distance between the nozzle surface and a take-off conveyor provided on a cooling medium for solidifying the resin, the melt viscosity of the resin, the hole diameter of the orifice, and the discharge amount. A pair of take-up conveyors with adjustable intervals installed on the cooling medium sandwich and hold the discharge line in the molten state to fuse the parts that are in contact with each other, and are continuously drawn into the cooling medium to be solidified. When the body is formed, by adjusting the distance between the conveyors, the thickness can be adjusted while the fused net is in a molten state, and a desired thickness can be obtained. The distance between the take-up conveyor and the nozzle surface is preferably within 30 cm. If the distance is too long, the molten wire is cooled and the contact portion is not fused, which is not preferable. If the conveyor speed is too high, the contact point may be insufficiently formed, or the contact point may be cooled until the fusion point is sufficiently formed, and the fusion of the contact portion may be insufficient. On the other hand, if the speed is too slow, the melt will stay too much and the density will increase, so it is necessary to set a conveyor speed suitable for the desired apparent density.

When the net-like structure of the present invention is used for a cushion material, a resin to be used depending on the purpose of use and the site of use,
It is necessary to select fineness, loop diameter and bulk density. For example, the wadding portion of the surface layer is preferably made to have a low density, fine fineness, and a small loop diameter in order to provide a soft touch and a moderate sinking and a firm bulge. In order to lower the resonance frequency, linearly change the appropriate hardness and the hysteresis at the time of compression to improve body shape retention and maintain durability, medium density, large fineness, and slightly larger loop diameter Is preferred. In addition, it is preferable to select a heat bonding component having good compatibility in order to obtain a bonding strength between the layer to be the cushion body and the object to be heated.
It can be formed into a shape suitable for the purpose of use by using a forming die or the like to the extent that the three-dimensional structure is not damaged. Also, at any stage during the processing from the manufacturing process to the molded body in a range that does not reduce the performance other than the resin manufacturing process, functions such as flame retardancy, insect repellent antibacterial, heat resistance, water and oil repellency, coloring, fragrance etc. Processing such as drug addition can be performed.

[0018]

The present invention will be described in detail with reference to the following examples.

The evaluation in the examples was performed by the following method. Endothermic peak at melting point (Tm) and below melting point Using an endothermic peak (melting peak) based on an endothermic curve measured at a heating rate of 20 ° C./min using a TA50, DSC50 type differential thermal analyzer manufactured by Shimadzu Corporation. ) Temperature was determined. The Tαcr polymer is heated to the melting point + 10 ° C., and the thickness is about 300 μm.
And a Tan δ (ratio M ″ / tan δ (imaginary elastic modulus M ″ and real part M ′ of elastic modulus) measured at 110 Hz and at a heating rate of 1 ° C./min using a Vibron DDVII model manufactured by Orientec. M ′) is the rise temperature of α-dispersion corresponding to the transition point temperature from the rubber elastic region to the melting region. Apparent density A sample is cut into a size of 15 cm × 15 cm, the height is measured at four locations, the volume is determined, and the weight of the sample is indicated by a value obtained by reducing the volume by the volume. (Average value of n = 4) Fused Samples are visually judged to determine whether or not they are fused. to decide. Heat resistance (70 ° C residual strain) Cut the sample into 15cm x 15cm size, compress it by 50%, leave it at 70 ° C for 22 hours in dry heat, cool it to remove the compressive strain, and leave it for one day, and before treatment Is expressed in% (n =
(Average value of 3) Repetitive compressive strain A sample was cut into a size of 15 cm × 15 cm, and 50% in a RH chamber at 25 ° C. and 65% with a SERVO pulsar manufactured by Shimadzu Corporation.
The compression recovery is repeated at a cycle of 1 Hz until the thickness of the sample reaches 20,000 times.
Indicated by (Average value of n = 3) Thermal adhesive strength A polyester fabric cut into a size of 15 cm x 15 cm and folded over a release sheet on the thermal adhesive surface, with the folded side at the center of the sample The heat-bonded molded product obtained by sandwiching two sheets in a heat press, preheating the woven fabric and the heat-bonded surface at a temperature 10 ° C. higher than the melting point of the low-melting elastic resin, and then compressing and heat-bonding , And folded back with the release sheet sandwiched, the portion of the woven fabric on the side that was not thermally bonded was sandwiched between chucks, and the woven fabric was pulled from both sides to measure the peeling force between the woven fabric and the thermally bonded net-like structure, Converted to the peeling force per 1 cm width, the thermal adhesive strength was determined, and the average value of n = 5 was 1 kg
/ Cm; less than 1 kg / cm and less than 3 kg / cm;
cm or more and less than 5 kg / cm; ○, 5 kg / cm or more; Seat comfort 30 ° C RH 75% Bucket seat on seat frame in room
A paneler sits on a seat in which a side of polyester moquette is hung on a cushion shaped like a letter (n = 5). (1) Feeling of flooring: The degree of "Donsu" when sitting and hitting the floor. Was qualitatively evaluated sensoryly. Not felt; ◎, almost felt; ○, slightly felt; △, felt; × (2) Feeling of stuffiness: After sitting for two hours, sensationally felt that the part in contact with the buttocks and the inner part of the crotch was stuffy. It was qualitatively evaluated. Almost no: ◎, slight stuffiness; ○, slight stuffiness; △, noticeable stuffiness; × (3) How long to be patient in 8 hours or less: 1 hour; × within 2 hours; △ within 4 hours;
○: 4 hours or more; ◎ (4) The degree of waist fatigue when seated in a seat for 4 hours was qualitatively evaluated sensoryly. None; ◎, hardly tired; ○, slightly tired; △, very tired; × (5) Overall evaluation: 4 points of ◎ in evaluation from (1) to (4), ○
Is 3 points, Δ is 2 points, and × is 1 point, 12 points or more do not contain Δ; very good (◎), 12 points or more include Δ; good (○), 10 points or more are × Was evaluated as poor (x), poor x (x), and poor (x).

Examples 1 and 2 Dimethyl terephthalate (DMT) or dimethyl naphthalate (DM) was used as the polyester elastomer.
N) and 1.4 butanediol (1.4 BD) were charged with a small amount of a catalyst, transesterified by a conventional method, and polytetramethylene glycol (PTMG) was added. Table 1 shows the formulation of the thermoplastic elastomer resin raw material obtained by forming a terester block copolymer elastomer, adding 1% of an antioxidant, mixing and kneading, pelletizing and drying at 50 ° C. for 48 hours.

[0021]

[Table 1]

The obtained two types of polyester-based thermoplastic elastic resins are melted by two extruders, and a pitch between rows is 5 mm in a length direction on an effective surface of a nozzle having a width of 50 cm and a length of 5 cm, and an orifice diameter. A was set to 0.7 mm, the pitch between the holes in the first, second, and eleventh rows was 5 mm, and the pitch between the holes in the third to tenth rows was 10 mm. And the second and eleventh rows, and A-2 was distributed from the third to the tenth rows.
1 was discharged at 1.26 g / minute, A-2 was discharged at 2.00 g / minute, cooling water was placed under the nozzle surface 12 cm, and the width was 60 cm.
A pair of take-up conveyors are arranged in parallel at 5 cm intervals so as to partially emerge above the water surface, and the stainless steel endless nets are taken at a speed of 1 m / min while sandwiching the contact portions while sandwiching both surfaces. Table 3 shows the characteristics of the net-like structure obtained by drawing into cooling water at 25 ° C., solidifying it, then subjecting it to pseudo-crystallization treatment in a hot-air dryer at 100 ° C. for 20 minutes, and then cutting it into a predetermined size. The average apparent density is 0.047
5 g / cm ³ , the apparent density and thickness of each layer were 1
The layer (table) in the row and the second row is about 8 m at 0.0675 g / cm ³
m, layer in 11th row (back) is 0.102 g / cm ³ and about 3 m
m, A-2 layer: 0.0404 g / cm ³ , about 41 mm, A-1 layer made of a low melting point elastic resin to be a heat bonding layer is a dense layer having a large number of components whose surface is substantially flattened. there were.

Example 2 As polyester-based elastomers, 80 mol% of dimethyl terephthalate (DMT), 20 mol% of dimethyl isophthalate (DMI), and 1.4 butanediol (1)
4BD) was charged with a small amount of a catalyst, transesterified by a conventional method, polytetramethylene glycol (PTMG) was added, and polycondensation was performed while raising the temperature and reducing the pressure to form a polyetherester block copolymer elastomer. Then, 1% of an antioxidant was added, mixed, kneaded, and pelletized.
Thermoplastic elastic resin raw material (A-
Table 1 shows the prescription of 3). Next, Table 3 shows the characteristics of the reticulated structure obtained in the same manner as in Example 1 except that A-3 was used as the low-melting point elastic resin to be the heat bonding layer. The apparent density and the thickness were almost the same as those in Example 1, and the A-3 layer was also a dense layer having a large number of components whose surface was substantially flattened.

Example 3 As a polyurethane elastomer, 4,4'-diphenylmethane diisocyanate (MDI), PTMG and 1.4BD as a chain extender were added to polymerize, and then 1% of an antioxidant was added. After mixing and kneading, pelletized and dried, polyether urethane was used as a thermoplastic elastic resin raw material. The formulations are shown in Table 2.

[0025]

[Table 2]

The obtained two types of polyurethane-based thermoplastic elastic resins were distributed in the first row, the second row, and the eleventh row of B-1, and the B-2 was distributed in the third to tenth rows. Then, at a melting temperature of 215 ° C., the single hole discharge amount was 1.26 g / B-1.
Table 3 shows the properties of the reticulated structure obtained in the same manner as in Example 1 except that the pores and B-2 were discharged at 2.00 g / pore and the pseudo-crystallization treatment was not performed. The obtained net-like structure was made of B made of a low-melting point elastic resin to serve as a heat bonding layer in the same manner as in Example 1.
The -1 layer was a dense layer having a large number of constituents whose surface was substantially flattened. The apparent density and thickness were almost the same as in Example 1.

Comparative Examples 1 and 2 First and second rows of polyester (PEIT) having a melting point of 115 ° C. obtained by copolymerizing 45 mol% of isophthalic acid having an intrinsic viscosity of 0.61, 55 mol% of terephthalic acid and ethylene glycol. The polyethylene terephthalate (PET) having an intrinsic viscosity of 0.63 was distributed from the third row to the tenth row, and the single hole discharge amount in each row at a melting temperature of 280 ° C. The network structure obtained in the same manner as in Example 1 and polyethylene (PE) having a melt index of 10 were distributed in the first, second and eleventh rows, and polypropylene (PP) having a melt index of 35 was distributed in the third row. To the 10th column,
Table 3 shows the characteristics of the network structure obtained in the same manner as in Example 1 for the single hole discharge amount in each row at a melting temperature of 220 ° C.

[0028]

[Table 3]

Comparative Example 3 The arrangement of the nozzle holes was 5 mm between rows and the pitch between holes was 10 mm.
From the nozzle with an orifice diameter of 0.7 mm, A
Table 3 shows the characteristics of the reticulated structure obtained under the same conditions as in Example 2 except that only the thermoplastic elastic resin of No. -3 was discharged at 235 ° C. at a single hole discharge rate of 2.0 g / min. Show. The average apparent density was 0.048 g / cm ³ and the thickness was about 50 mm. When the bonding treatment was performed to measure the thermal bonding strength, the thickness was reduced to about 32 mm and did not recover.

Comparative Example 4 Example 1 was repeated except that the take-up conveyor net was arranged 60 cm below the nozzle surface and the pseudo-crystallization treatment was not performed after the take-up conveyor net.
Table 3 shows some of the characteristics of the reticulated structure obtained in the same manner as in Example 1. In addition, since the adhesion state is poor and the shape retention is poor, the evaluation of the apparent density, the residual strain at 70 ° C., the repeated compression strain, and the thermal adhesion strength is not performed.

Example 1 is a preferred net-like structure suitable for a cushion material having a soft and moderate sinking, a good heat resistance and durability using a polyester polymer, and a good heat bonding strength. Example 2 is an example in which the temperature of the heat bonding component is lowered and the heat bonding strength is improved. Example 3 was an example in which a pseudo-crystallization treatment using a polyurethane polymer was not performed, and the seating comfort was very good and the adhesive strength was good. Comparative Examples 1 and 2 are examples using a thermoplastic inelastic resin, and have no endothermic peak below the melting point even after pseudo-crystallization treatment, and have extremely poor heat resistance and durability, and are hard and comfortable to sit on. This is an example that is extremely bad and is not suitable for a cushion material. However, the adhesive strength was good. Comparative Example 3 is an example comprising a single-component elastic resin layer and deviating from the scope of the present invention, in which the durability and sitting comfort are inferior to those in Example 1, and the thickness of the cushion layer is reduced due to partial melting at the time of bonding. Problems during molding also become significant. Comparative Example 4 is an example in which fibers are not fused to each other, and has an extremely poor shape retention and is not suitable for a cushion material.

[0032]

As described above, the network structure of the present invention has a heat-adhesive layer made of a thermoplastic low-melting elastic resin in which filaments made of a thermoplastic elastic resin are fused and integrated on one or both sides. A new molded body can be easily formed by bonding, and the thermal bonding layer and the cushion function layer made of high melting point elastic resin are integrally deformed by the external force deformation of the bonded layer to be bonded, and stress When the external force is removed, it can be restored to its original form by the elasticity of the elastic resin, so it has better sitting comfort, heat resistance, bulkiness, and moderate compression repulsion. This is a heat-adhesive net-like structure suitable for a vulnerable cushion material and easy to recycle, which is useful for vehicle seats, marine seats, furniture cushions, and bedding products. It can be used alone or in combination with other materials. Furthermore, it is a heat-adhesive net-like structure that is also useful for heat insulating materials, interior materials, heat insulating materials, stretchable nonwoven fabrics, and the like.

────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-1-207462 (JP, A) JP-A-1-213454 (JP, A) JP-A-5-138789 (JP, A) JP-A-5-138789 272043 (JP, A) JP-A-5-329281 (JP, A) JP-A-5-261184 (JP, A) JP-A-5-337258 (JP, A) (58) Fields investigated (Int. ⁷ , DB name) D04H 1/00-18/00 B68G 1/00-15/00 B32B 1/00-35/00

Claims (4)

(57) [Claims] 1. A network structure made of a high melting point and low melting point thermoplastic elastic resin, and a low melting point thermoplastic elastic resin having a melting point of 10 ° C. or more lower than the melting point of the high melting point thermoplastic elastic resin forms a heat bonding layer. The network structure made of a high melting point thermoplastic elastic resin forms the basic layer, and both layers are three-dimensional random loops.
Is a heat-adhesive network structure that is fused and integrated at the time of forming the loop, and the network structure winds a continuous filament to form a large number of loops, and brings the respective loops into contact with each other. Most of is fused, is a three-dimensional random loop structure having a constant width and thickness, one or both sides of the heat-adhesive network is formed of a substantially flat heat-adhesion layer, A heat-adhesive network structure, wherein the thickness of the heat-adhesive layer is 1 mm or more and 10 mm or less. 2. A loop forming a network structure is pushed and bent at least 45 ° from the base line in the middle of the loop with the thickness direction of the network structure as a base line, and most of the contact portions are fused. 2. The thermoadhesive network of claim 1, wherein the structure is substantially flat. 3. A heat-bonding layer made of a low-melting thermoplastic elastic resin is formed on one or both surfaces of the network structure, and a melting point higher than the melting point of the thermoplastic elastic resin by at least 10 ° C. in a portion other than the heat-bonding layer. From a nozzle distributed so that a basic layer made of a thermoplastic elastic resin having is formed, a resin in a molten state is discharged downward at a temperature higher by 10 to 120 ° C. than a melting point of each resin, and is discharged in a molten state. A large number of loops are formed, each loop is in contact with each other and fused to form a three-dimensional random loop structure with a constant width and thickness, and sandwiched by a take-off device to substantially flatten the surface It is allowed to allowed to cool in the cooling bath, the base and the heat adhesive layer
Preparation of thermoadhesive net structure, characterized in that fusing together of the main layer. 4. Once cooled, at least 10 ° C. below the melting point
4. The method according to claim 3, wherein annealing is performed at a lower temperature.