JPH0151255B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a method for manufacturing a dust control mat equipped with a polyurethane backing, and more specifically, it relates to flexibility, lightness, dimensional stability, durability, adhesion to the floor, and This invention relates to a method for manufacturing dust control mat with excellent texture on the pile surface. (Prior art and its problems) In order to prevent dust attached to the soles of shoes etc. from entering indoors or indoors, it is formed by making a base fabric and tufting pile yarn on the base fabric and trimming the ends. Dust control mats (dusting mats) consisting of a pile surface and an elastomeric polymer backing applied to the opposite side of the base fabric from the pile surface are widely used. Such dust control mats (hereinafter simply referred to as mats) are placed in entrances or indoors and used for a certain period of time, and they can be used under harsh conditions because they become extremely dirty after use. They are used repeatedly and are subject to washing, and require a high degree of dimensional stability, durability, etc. In conventional mats, it is customary to back them with polyvinyl chloride, synthetic rubber, natural rubber, etc., or a mixture thereof, and in the case of polyvinyl chloride, the contraction and expansion rates of the pile base fabric and backing material are Due to the difference, when laying the pine, there are defects such as curling up and the strength is unsatisfactory, and when synthetic rubber, natural rubber, etc. are used as backing materials, the use of hot press is unavoidable as a vulcanization condition for rubber. Therefore, in addition to the drawback that the pile part becomes flattened by hot pressing, which impairs the appearance and dust trapping, the weight of the backing part generally increases, which hinders the handling benefits of weight reduction. It's summery. Even if polyvinyl chloride and synthetic rubber or natural rubber are blended in any ratio, it is impossible to solve the above-mentioned disadvantages, and the disadvantages of each are merely added to each other. (Object of the Invention) Therefore, the object of the present invention is to provide a dust control with polyurethane backing that has excellent flexibility, lightness, dimensional stability, durability, adhesion to floors, etc., and texture or napping of the pile surface. The present invention provides a method for manufacturing a pine tree. Another object of the present invention is that the pile yarn tufted base fabric and the polyurethane backing are firmly bonded, and even when the thickness or weight of the backing layer is extremely small, the mat remains stable on surfaces such as floors. The present invention provides a method for manufacturing a dust control mat that is retained in a dust control mat. Still another object of the present invention is to provide a method for manufacturing a dust control mat which is lightweight and flexible when being transported or moved, and which does not have drawbacks such as fitting to the floor surface and curling up when laid. (Structure of the Invention) The present invention provides a pile yarn tufted base fabric having a pile surface formed by tufting pile yarn on a base fabric and trimming the ends thereof, and a polyisocyanate on the opposite side to the pile surface. It is formed by a reaction with a polyether polyol or a polyester polyol, and is laminated with a polyurethane resin layer that is in a semi-cured state with a still sticky surface and contains a blowing agent, and then heated to a temperature of 110 to 130°C to form the foam. The polyurethane resin layer is foamed and simultaneously cured to create a pile yarn tufted base fabric with a foaming ratio of 1.2.
This is a method for producing a dust control mat equipped with a urethane backing, characterized by integrating a low-foam polyurethane resin layer of 2.5 to 2.5 times. (Preferred embodiments of the invention) The present invention will be described in detail below with reference to the accompanying drawings. In FIG. 1 showing a cross section of a dust control mat manufactured by the method of the present invention, this mat has a base fabric 1, a pile surface formed by tufting pile yarn 2 on this base fabric and trimming the tips thereof. 3, and a polyurethane backing 4 applied to the surface of the base fabric 1 opposite to the pile surface. This mat is made of polyurethane backing 4.
is a polyisocyanate, that is, a polyurethane obtained by reacting a polyfunctional isocyanate compound with a polyether polyol or a polyester polyol, with an expansion ratio of 1.2 to 2.5 times, especially 1.5 to 2.5 times.
The backing 4 and the pile yarn tufted base fabric 1 are made of a 2.0 times low foam, especially a closed cell foam, and the backing 4 and the pile yarn tufted base fabric 1 are composed of a semi-cured polyurethane layer whose surface is still sticky and a pile yarn tufted base fabric. A distinctive feature is that it is formed by laminating a polyurethane layer and then curing this polyurethane layer. That is, in FIG. 2 showing an example of the manufacturing process of this urethane bucking mat, an endless belt 12 is movably supported by a pair of pulleys 10 and 11. Polyisocyanate 13 is stored in a storage tank 14, and polyols 15 are stored in a storage tank 16, which are connected to pipes 17 and 18.
A fixed amount of the liquid is supplied to the mixing head 19 through the process.
In this mixing head 19, polyisocyanate 13 and polyols 15 are mixed in a stoichiometric ratio together with predetermined amounts of catalyst and blowing agent (not shown). Mixing head 19
The composition formed is supplied to the introduction side of the endless belt 12, and is applied onto the endless belt 12 to form a resin layer 21 of a predetermined thickness by a coating mechanism 20 which is known per se, such as a roll doctor or an air knife coater. Ru. On the other hand, the pile yarn tufted base fabric 22 is also supplied to the introduction side of the endless belt 12, and is stacked on the resin layer 21 such that the surface of the base fabric opposite to the tufted surface faces the resin layer 21. The pile yarn tufted base fabric 22 superimposed on the resin layer 21 is lightly pressed against the resin layer 21 by a presser roller 23. In the present invention, the pile yarn tufted base fabric 22
The state of the polyurethane resin layer 21, which is overlapped with the polyurethane resin layer 21, has progressed to a certain extent to become a resin due to the reaction between the polyisocyanate and the polyols, and can withstand the weight and light pressure of the pile yarn tufted base fabric 22, but it is still at least The surface is in a semi-cured state with adhesive properties. This semi-cured state is a state where the viscosity of the polyurethane resin on the surface is between 5,000 and 20,000 centipoise, and by laminating the polyurethane resin layer in a semi-cured state with the pile yarn tufted base fabric, the polyurethane resin of the base fabric The embedding into the layer is moderately and reliably performed. The laminate 24 on the endless belt 12 is introduced into the tunnel furnace 25 as the endless belt 12 is driven, and heated to a predetermined temperature to complete curing and foaming of the polyurethane resin layer. The laminate 25 discharged from the tunnel furnace 25 is a strongly integrated mat with a polyurethane backing, and is peeled off from the endless belt 12 to become a product. The polyurethane-backed mat manufactured according to the present invention has notable features due to the above-mentioned configuration. That is, in the present invention, the pile planting base fabric is attached to the polyurethane resin layer that has been spread in advance on the endless belt while remaining adhesive, and the pile is compressed by simply pressing lightly if necessary. By being commercialized in a brushed state without being subjected to distortion, it has excellent dust collection properties, appearance, and feel, and the specific gravity can be arbitrarily reduced by slightly foaming the polyurethane resin. At the same time, the amount of relatively expensive urethane resin used can be reduced and made economical.
Furthermore, due to the excellent mechanical strength of polyurethane resin, it is possible to make the thickness of the backing layer in the range of 0.7 mm to 2.0 mm, resulting in extremely significant advantages such as being able to provide a thin and lightweight backing mat. Ru. In particular, in order to bond the pile implanted base fabric to the polyurethane resin layer at room temperature, there is no need to apply any special pressure from the outside; simply place the pile implanted base fabric on the polyurethane resin layer and press lightly as necessary. At this time, if the uncured polyurethane resin is charged into a tunnel heating furnace for heat curing while being adhered to the base fabric, controlled low foaming will occur here and the foaming pressure will further increase the foaming pressure. The polyurethane resin penetrates into the base fabric, creating a more complete bond. In short, in the case of the present invention, lamination adhesion occurs in the first stage between the polyurethane resin layer and the pile-planted base fabric, and intrusion adhesion occurs in the second stage due to foaming pressure, resulting in a complete buckling structure. . In the urethane backing mat manufactured according to the present invention, as described above, the adhesion between the base fabric and the backing material is perfect, and the shrinkage of the pile fibers, base fabric fibers, and polyurethane resin is prevented.
Since the expansion is similar, it is possible to completely eliminate defects such as curling up, and it also has the advantage of good adhesion to the installation site and no slippage of the mat. Furthermore, as a catalyst for crosslinking and curing polyurethane resin,
By choosing a heat-sensitive catalyst, no significant curing occurs near room temperature regardless of the time elapsed until the polyurethane resin spreads, and by heating to 110°C to 130°C for a few minutes to several tens of minutes, it forms a completely crosslinked network structure, which is required. The present invention provides a urethane backing mat that has remarkable features such as mechanical strength and washing resistance. Furthermore, since the reaction between the polyisocyanate and polyols described above is an exothermic reaction, the polyurethane resin can be cured or It also has the advantage that it can be reticulated and therefore has very little tendency to deteriorate the mechanical properties or the degree of napping of the pile yarn. In the present invention, as the polyisocyanate, difunctional, trifunctional, and tetrafunctional isocyanate compounds are used, such as tolylene diisocyanate, cyclohexane diisocyanate,
Hexamethylene diisocyanate, diphenyl
4,4'-diisocyanate, diphenylmethane-
4,4'-diisocyanate and the like are used. Examples of polyols include polyether polyols made of polyethylene glycol, polypropylene glycol, or ethylene oxide adducts to polyhydric alcohols such as mannite, sorbitol, and pentaerythritol, and dibasic acids such as adipic acid and succinic acid. A hydroxyl-terminated polyester derived from a glycol component such as ethylene glycol or propylene glycol, that is, a polyester polyol, is used. The above-mentioned polyisocyanate and polyols are mixed in stoichiometric amounts and used as a polyurethane resin composition. As catalysts, various amines,
In particular, catalysts known per se such as tertiary amines such as dimethylaniline and tetramethyl-P-phenylenediamine are used. As a blowing agent, gases such as air, nitrogen gas, carbon dioxide gas, etc. can be mixed and used by a method called mechanical foaming, but azodicarbonamides, azobisisobutyronitriles, ammonium carbonate, etc. Chemical blowing agents can also be used. It is a common practice to add carbon black as a black pigment to these polyurethane resins to color them black and at the same time to significantly increase their light resistance. At the same time, apart from carbon black, colored pigments or dyes can be added to create transparent colors such as red, orange, green, yellow, etc.
A fashionable backing mat that is colored blue or the like and has a color tone that is in harmony with the pile color is also a feature of the urethane backing mat produced by the method of the present invention. Naturally, white urethane backing mats made of titanium white or zinc white also have special features depending on the application. Separately, with the aim of further compressive strength, excellent recovery properties, and reduction of hysteresis loss, glass fiber,
When fine powder mica or the like is added, a urethane backing material with relatively low density and greatly increased modulus is obtained. In the present invention, it is important to set the foaming ratio of the polyurethane backing in the range of 1.2 to 2.5 times in terms of flexibility, lightness, adhesion to the floor, etc. mentioned above, and if the foaming ratio is lower than the above range, On the other hand, increasing the expansion ratio higher than the above range is disadvantageous in terms of durability, washing resistance, and mechanical strength. In this specification, the expansion ratio is defined as a value divided by the true specific gravity of the polyurethane resin by the apparent specific gravity. In the present invention, in order to further improve the adhesion of the mat to the floor surface, as shown in the sectional view of FIG.
, a circumferential protrusion 5 and a recess 6 surrounded by the protrusion.
It is sufficient to form a pattern consisting of the above-mentioned endless belt 12, and the formation of such a pattern can be easily carried out by using the aforementioned endless belt 12 on which a pattern corresponding to this has been formed in advance. . Peeling between the endless belt 12 and the cured urethane backing 4 is easily accomplished by forming the belt surface with a non-adhesive material such as polytetrafluoroethylene. Furthermore, if such a pattern is formed on the surface of the endless belt that spreads and supports the urethane resin layer, even if the pile-embedded base fabric is laminated with the urethane resin layer having a considerably low viscosity, This effectively eliminates the problem of the base fabric protruding from the back side of the backing. The base fabric and pile yarn in the mat of the present invention are
Mats for dust control are known per se. For example, as the base fabric, woven fabrics, gauze, non-woven fabrics, etc. made of synthetic fibers such as polyester fibers or natural fibers such as cotton are used, while as the pile threads, nylon fibers are used. Spun yarns, multifilament yarns, etc. of various fibers such as acrylic fibers, polyvinyl alcohol fibers, vinyl chloride fibers, and cellulose fibers are used. In the mat of the present invention, since the pile yarn has little tendency to lie during manufacture, there is an advantage that an excellent nap state is maintained even when the pile length is increased to, for example, 12 mm. The invention is illustrated by the following example. Example 1 100.0 parts of adipic acid and diethylene glycol
A polyester prepared by adding 1.0 part of ammonium carbonate, 1.0 part of semicarbazide, 0.05 part of tetramethyl-P-phenylenediamine, and 0.5 part of carbon black to 100.0 parts of a polyol polyester produced using 72.7 parts of trimethylolpropane and 4.5 parts of trimethylolpropane, and mixing with stirring. Prepare a liquid, and add MTL of liquid MT manufactured by Nippon Polyurethane Co., Ltd. corresponding to 55.5 parts of 4,4'-diisocyano diphenylmethane to this using a casting machine equipped with a metering pump and a mixing head while maintaining the volume ratio. Coat it on the endless belt to a thickness of 0.8 mm using a discharge roll coater and a knife coater, and after 2 minutes, add pile-planted base fabric (pile: 6, nylon, base fabric, polyester) continuously. 120 in tunnel heating furnace
℃ for 10 minutes, and after the polyurethane resin of the backing had hardened, it was cut into specified dimensions to obtain a urethane backing mat. In this case, the thickness of the polyurethane resin backing layer was 0.9 mm as expected due to foaming, and the apparent specific gravity of the resin layer was 0.85. The strength and elongation of the polyurethane resin sheet for the backing part of the urethane backing mat obtained here was measured, and the strength and elongation were as follows, indicating that it was sufficiently usable. Strength test (20℃, atmosphere) Longitudinal direction Lateral direction Tensile strength 75.0Kg/cm ² 72.8Kg/cm ² Tear strength 31.5Kg/cm 35.2Kg/cm Elongation 385.0% 390.0% Example 2 In Example 1, A urethane backing mat was produced in the same manner as in Example 1 except that the heating temperature and expansion ratio shown in Table 1 were adopted. Five pieces of each of the resulting mats were washed in 50°C water for 12 minutes using a vertical washing machine (capacity 30K, rotation speed 30 rpm), and then washed in a centrifugal dehydrator (capacity 32K, rotation speed 1120 rpm) for 25 minutes, and then dried at 80°C using a tumble dryer (capacity 18K, electric heating 15KW). The strength of the pine after the test is judged as ○, △, ×.
The results are shown in Table 1.

[Table] From this result, if the heating temperature is lower than 110℃, the curing reaction will not take place sufficiently, and the mat will not have sufficient washing resistance.If the heating temperature is higher than 130℃, it will not harden. It is understood that because the reaction proceeds too quickly, the polyurethane does not sufficiently penetrate into the base fabric, and therefore sufficient wash resistance cannot be obtained. Furthermore, sufficient strength cannot be obtained even when the expansion ratio is 2.5 times or more. In Table 1, ○ indicates a longitudinal tensile strength of 80 Kg/cm ² or more, Δ indicates a range of 50 to 80 Kg/cm ² , and × indicates a longitudinal tensile strength of 50 Kg/cm ² or less.

[Brief explanation of drawings]

FIG. 1 is an enlarged sectional view of a dust control mat manufactured by the method of the present invention;
The figure is an explanatory diagram showing the manufacturing process. Reference number 1 indicates the base fabric, 2 indicates the pile yarn, 3 indicates the pile surface, and 4 indicates the polyurethane backing.

Claims (1)

[Claims] 1. A pile yarn tufted base fabric having a pile surface formed by tufting pile yarn on a base fabric and trimming the tips thereof is treated by reacting a polyisocyanate with a polyol or a polyester polyol on the surface opposite to the pile surface. The polyurethane resin layer is formed and is in a semi-cured state with a sticky surface, and is overlapped with a polyurethane resin layer containing a foaming agent, and then heated to a temperature of 110 to 130°C to foam the polyurethane resin layer and simultaneously harden it. A method for producing a dust control mat having a urethane backing, characterized in that a pile yarn tufted base fabric and a low foam polyurethane resin layer with an expansion ratio of 1.2 to 2.5 times are integrated.