JPH11178701A - Production of carpet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process for producing a carpet which provides a carpet having sufficient strength together with flexibility and is capable of shortening the time for drying and curing. SOLUTION: A Backing material slurry 21 prepd. by using a cement compsn. composed of hydraulic inorg. powder contg. 4 to 25 wt.% alumina cement and an aq. resin dispersion is molded to a sheet form and a carpet base material 12 is superposed on the sheet-like material to form a laminate. While the laminate is moved on an electric heater 5 as a heating section, the sheet is heated from its lower side and is dried and cured, by which the carpet 1 is continuously produced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a carpet to be laid on a bare ground of a building or the like, and more particularly to a method of manufacturing a carpet having excellent backing strength by laminating a backing material on a back surface of a carpet substrate on which piles are planted.

[0002]

2. Description of the Related Art Carpet backing materials include asphalt and vinyl chloride materials. However, asphalt-based ones not only have an odor,
It becomes hard and cracks especially in winter. On the other hand, at high temperatures, there were problems such as softening and soiling of the surroundings, and heat degradation. In the case of vinyl chloride, carpet disposal
During incineration, harmful chlorine gas was generated and there was a problem of environmental pollution.

In order to solve the above problem, a cement composition comprising an aqueous resin dispersion and hydraulic inorganic powder is used as a backing material, and the backing material is continuously formed, and then a carpet base material is bonded. A method of manufacturing a carpet by drying and hardening a backing material has been proposed (JP-A-5-254081, JP-A-5-25408).
No. 2, JP-A-6-154070).

[0004] However, the above-mentioned method has a drawback that it takes time to dry and harden and the productivity is poor. on the other hand,
If the drying temperature is increased to speed up drying and hardening in order to increase productivity, water vapor in the backing material causes bubbles and swelling due to water vapor during evaporation. Further, there is a problem that the strength of the obtained backing material is reduced.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and provides a carpet having sufficient strength and flexibility. It is an object of the present invention to provide a method of manufacturing a carpet, which can reduce the cost.

[0006]

According to the first aspect of the present invention, 4 to 25% by weight is used.
A backing material slurry made of a cement composition comprising a hydraulic inorganic powder containing alumina cement and an aqueous resin dispersion is formed into a sheet, and then a carpet base is formed on the obtained sheet. The carpet is continuously produced by stacking the materials to form a laminate, and then heating and drying and curing the laminate from below the sheet while moving the laminate on the heating unit. In the method of manufacturing carpets.

Next, the function and effect of the present invention will be described.
In the present invention, a mixture of a hydraulic inorganic powder containing alumina cement in a specific range as described above and an aqueous resin dispersion is used as the backing material slurry. Therefore, the water does not suddenly expand and evaporate in the backing material slurry during the drying and curing.

Therefore, no bubbles or blisters are generated in the backing material of the obtained carpet, and the strength is not reduced. Since the backing material slurry is used, the backing material also has sufficient flexibility.

The drying and curing of the laminate are performed while moving the laminate over a heating unit. Therefore, there is no rapid expansion and evaporation of water as described above, and the time for drying and hardening can be shortened.

Hereinafter, the present invention will be described in detail. The carpet of the present invention uses a mixture of an aqueous resin dispersion and a cement composition composed of hydraulic inorganic powder as a backing material slurry. As the hydraulic inorganic powder, one containing 4 to 25% by weight of alumina cement is used.

In the present invention, the aqueous resin dispersion used for the backing material slurry is obtained by emulsion-polymerizing one or more kinds of various unsaturated monomers having various glass transition points to give a homopolymer. be able to. As the unsaturated monomer, various monomers having a polymerizable double bond can be used. For example, various (meth) acrylic esters, styrene, (meth) acrylonitrile, (meth) acrylamides , (Meth) acrylic acid, other unsaturated carboxylic acids, vinyl chloride, vinyl acetate, other vinyl esters, ethylene, butadiene, vinyl ethers and the like.

The aqueous resin dispersion can be obtained by emulsion polymerization of the above monomers in water using a surfactant or a protective colloid by a known method.

[0013] Next, as in the third aspect of the present invention, both are blended so that the resin component in the aqueous resin dispersion is 25 to 200 parts by weight with respect to 100 parts by weight of the hydraulic inorganic powder. preferable. In this case, the effect of improving the strength can be obtained by the elasticity of the resin and the hydraulic inorganic powder. If the amount is less than 25 parts by weight, there is a problem that the carpet becomes hard and brittle and easily broken. On the other hand, if it exceeds 200 parts by weight, there is a problem that the carpet becomes too soft, the strength is reduced, and the dimensional stability is deteriorated.

Next, as described in claim 4, the glass transition point of the aqueous resin dispersion is preferably -40 ° C to 5 ° C. Thereby, the flexibility, strength, etc. of the obtained carpet can be improved. Below -40 ° C, the strength is low and the dimensional stability is poor. On the other hand, when the temperature exceeds 5 ° C., there is a problem that the carpet becomes hard and brittle. The glass point transfer can be determined by differential scanning calorimetry (DSC).

Next, in the present invention, two or more kinds of aqueous resin dispersions having different compositions and different glass transition points can be used in combination. It is also possible to use re-emulsifiable resin powders obtained from these resin aqueous dispersions.

The alumina cement used for the backing material slurry in the present invention is obtained by firing alumina and calcium oxide in an electric furnace or a rotary kiln. The above alumina cement contains 4
-25% by weight. If the amount is less than 4% by weight, there is a problem that the strength of the backing material is low, and drying and curing are slow. On the other hand, if it exceeds 25% by weight, there is a problem that the backing material becomes brittle and shrinkage during drying becomes large.

The hydraulic inorganic powder other than alumina cement used in the backing material slurry in the present invention includes:
Portland cements such as ordinary Portland cement, white Portland cement, early-strength Portland cement, ultra-high-strength Portland cement, sulfate-resistant Portland cement, medium heat Portland cement, etc., mixed cements such as blast furnace cement, silica cement, fly ash cement, etc. There are hydraulic lime and hydraulic gypsum.

Next, as in the invention of claim 5, as the setting retarder added to the backing material slurry, at least one of gluconic acid, gluconate, citric acid and citrate is used. A method of manufacturing a carpet, characterized in that: In this case, the change in the viscosity of the backing material slurry can be stabilized. For this reason, there is no change in the fluidity of the backing material slurry, so that not only a uniform sheet can be formed, but also troubles such as thickening and clogging in the piping do not occur.

Other than the above, examples of the setting retarder include malic acid or a salt thereof, salicylic acid or a salt thereof, tartaric acid or a salt thereof, sugars such as sucrose, glucose, and lactose, and soluble starch. The amount of the setting retarder used is
In order to obtain the above effects, it is preferable to use 0.1 to 3.0 parts with respect to 100 parts of the total cement.

In the present invention, it is preferable that an aggregate is mixed into the backing material slurry. This gives
The strength of the backing material is improved. Such aggregates include:
Inorganic such as silica sand, silica powder, charcoal, talc, mica, diatomaceous earth, kaolin, quartz, iron powder, fly ash, pozzolan, blast furnace slag, titanium oxide, asbestos powder, white carbon, zinc oxide, zirconia, carbon black Examples include inorganic lightweight aggregates such as powder, shirasu balloon, perlite, and glass sphere particles, expanded resin particles such as expanded polystyrene and expanded polyethylene, and organic powders such as tire chips and rubber powder.

In addition, as long as the performance of the backing material in the obtained carpet is not impaired, a dispersant, a water reducing agent, a hardening accelerator, a quick-setting agent, a wetting agent, a defoaming agent,
Various additives such as a solvent, a plasticizer, a film-forming aid, an antifreezing agent, and a thickener may be blended in the backing material slurry.

In order to manufacture the carpet of the present invention, first, the above cement composition is uniformly mixed and dispersed by a mortar mixer, a mixing pot equipped with a stirrer, a high-speed disper, or the like.
Obtain backing material slurry. Next, the backing material slurry is placed on a moving means such as an endless belt whose surface is made of an easily peelable material (for example, Teflon).
It is formed into a sheet by a knife coater, roll coater or the like so that the thickness becomes uniform.

Next, if necessary, a carpet base material made of a spun bond made of polyester or the like and synthetic resin fibers made of nylon, polyester, polypropylene or the like or a needle-punched fiber was formed into a sheet. Paste on backing material.

Note that, on the surface to be bonded to the backing material,
Aqueous resin dispersions such as SBR latex, EVA emulsion and acrylic emulsion can be used as filler. Apply these fillers with knife coater, spray,
It can be applied by dipping, roll coating or the like. In this case, when the carpet base material is used after being laid on the floor, it is possible to prevent pile removal (thread removal strength), fuzziness of the fiber (fuzz class), and the like.

The carpet base material coated with the filler is bonded to the backing material by drying the filler and then bonding to the backing material, or by laminating the filler without drying. There is. In the present production method, it is preferable to bond the undried material from the backing material in view of the familiarity with the backing material, the thread removal strength, and the adhesiveness such as fuzz.

In order to improve the strength of the backing material formed into a sheet and to secure dimensional stability, it is preferable to insert a nonwoven glass fabric between the sheets. The method is as follows: first, a sheet of the backing material slurry is made into a first layer, and then a cloth material such as a glass non-woven fabric is placed thereon, and then the backing material slurry is placed thereon again to form a second layer sheet. create. Examples of the cloth material include a glass nonwoven fabric, a glass mesh, an organic nonwoven fabric and a mesh. Further, if the strength of the backing material is sufficient, the interposition may be omitted.
Further, the composition of the backing material slurry of the first layer (lower side) and the second layer (carpet substrate side) may be the same or different.

Next, the backing material and the carpet base material are bonded together and pressed with a nip roll or the like. Then, adhesion between the carpet base material and the backing material is ensured, and the thickness is set to an arbitrary thickness.

The laminate whose thickness has been set in this way is
Move to drying / curing process. The water in the composition slurry is
It is heated in the drying and hardening process, evaporates and escapes from the slurry, and the backing material becomes a sheet of non-volatile components. Next, the laminate is heated from below while being moved by a moving means such as an endless belt. This heating is performed by disposing a heating means at a part below the moving means. Examples of the heating means include an electric heater and hot air.

In this heating and drying step, the higher the temperature, the better from the viewpoint of productivity, but if the initial temperature is too high,
The backing material slurry easily foams. As a countermeasure, the water content of the backing material slurry was reduced,
There is a method of efficiently removing water by gradually increasing the temperature.

Next, as in the second aspect of the present invention, during the drying and curing, the carpet can be continuously fed into a dryer to be dried and cured. In this case, productivity is improved because the latter half of drying is performed in a dryer. Examples of the heating and drying means in the dryer include hot air drying, radiant heat drying using an electric heater, a far-infrared heater, and the like, and internal heat drying using high frequency and microwave.

In the drying and curing, the water content in the backing material is preferably set to 2% or less.
If the water content exceeds 2%, shrinkage or warpage may occur in the tile carpet due to aging.

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail. Embodiment Example As shown in FIG. 2, the carpet 1 obtained in this example
Consists of a backing material 11 and a carpet substrate 12 adhered to the backing material 11. The backing material 11
The backing material slurry described below is dried and hardened. The expansion ratio of the backing material 11 is 1.0 to 1.0.
1.5. As shown in FIG. 2, the backing material 11 has small bubbles 111 generated by foaming, while the carpet base material 12 has flocking 13.

Next, an apparatus and a method for manufacturing the carpet will be described with reference to FIG. First, the manufacturing apparatus includes a conveyor belt 55 made of ethylene tetrafluoride and a first belt.
A first tank 2 containing a backing material slurry 21, a second tank 3 containing a second backing material slurry 31,
And an electric heater 5 as a heating unit provided below the conveyor belt 55. Further, it has a group of rollers 45 for supplying the carpet base material 12 onto the backing material, and a dipping roll 41 for applying a coating agent 49 for filling the carpet on the back surface of the carpet base material 12.

Further, the apparatus has rollers 551 and 552 for rotating the conveyor belt 55. A hot air circulation type dryer 6 is provided behind the rear roller 552. The dryer 6 has a group of rollers 61 and 62 for moving the laminate 10 up and down.

Then, the carpet 1 is
When manufacturing the first tank 2, the conveyor belt 55 is moved by the driving roller 551, and the first tank 2 is placed thereon.
Then, the first backing material slurry 21 is continuously supplied, and is made to have a constant thickness by the doctor knife 53. Then,
A glass nonwoven fabric 25 is overlaid on the first backing material slurry 21 sent at a constant thickness via a roller 251, and then a second backing material slurry 31 is continuously supplied from the second tank 3 onto the glass nonwoven fabric 25. Supply. Then, the thickness of the second backing material slurry 31 is made constant by the doctor knife 54.

Next, the second backing material slurry 3
1, a carpet substrate 12 coated with the coating agent 49
Are laminated to form a laminate 10. At this time, press roll 47
Presses the carpet substrate 12. Next, the lower surface of the laminate 10 continuously fed as described above is heated by the electric heater 5 from below the conveyor belt 55.

By this heating, the first and second backing material slurries 21 and 31 are heated and dried, and
The water therein evaporates and escapes to the outside, and the backing material foams. At the rear of the electric heater 5, the laminate 10 is peeled off from the conveyor belt 55, and is sent to the dryer via the rollers 58. Then, in the dryer 6, the stacked body 10 is meandered in the vertical direction by the roller groups 61 and 62, thereby forming the stacked body 1.
Dry 0. As a result, the first and second backing material slurries 21 and 31 are finally hardened, and the carpet 1 shown in FIG. 2 can be manufactured.

Example 1 First, Portland cement (Mitsubishi Materials Corporation)
A hydraulic inorganic powder consisting of 180 parts by weight and 20 parts by weight of alumina cement (Denka Alumina Cement No. 1, Denki Kagaku Kogyo Co., Ltd.) was prepared.
200 parts by weight of Acronal S400 (aqueous resin dispersion of acrylate-styrene copolymer of Mitsubishi Chemical BASF Co., Ltd., solid content: 57%, Tg: about -6 ° C) were added.

Further, 250 parts by weight of KD-100 calcium carbonate [Dowa Calfine Co., Ltd.], 5 parts by weight of a cement water reducing agent Mighty 150 (Kao Corporation), and a defoamer Nopco 8034 (San Nopco Co., Ltd.) 3 parts by weight, 2 parts by weight of sodium gluconate, and 30 parts by weight of water were added. Next, these were mixed for 10 minutes by a mixer with a stirring blade to obtain a backing material slurry 21 having a slurry concentration of about 80%.

Next, the backing material slurry 21 was poured from the tank 2 onto the Teflon-made conveyor belt 55, and the backing material slurry 21 was adjusted to a thickness of 1.5 mm by the knife coater 53. The conveyor belt 55 is driven endlessly, and the slurry whose thickness is controlled moves as a uniform sheet.

Next, a glass nonwoven fabric (basis weight: 150 g) 25 is placed on the surface of the sheet along with the sheet, and a backing slurry 31 for the second layer from the tank 3 is poured onto the sheet. The sheet thickness was adjusted to 2.5 mm with the knife coater 54 in the same manner as the layer.

On the other hand, a nylon tufted carpet base material (basis weight: 800 g / m ² ) having a polyester non-woven fabric as a primary base fabric is used as the carpet base material 12, and the coating material for the base material, Acronal 2716D (Mitsubishi Chemical) BA
SF Company, trade name; resin aqueous dispersion of acrylate-styrene copolymer, solid content concentration 48%, MFT24
° C) by the dipping roll 41 to apply 300
g / m ² . Next, the carpet base material 12 having the back surface coated with the coating agent 49 as described above is placed on the sheet 27, and the holding roll 47 applies 6.5 mm.
To obtain a laminate 10.

Next, the laminate 10 was moved to the upper part of the electric heater 5 at 95 ° C., where it was heated for 15 minutes. Thereafter, the laminate 10 is peeled off from the conveyor belt 55, and
The carpet 1 was obtained by drying with a hot air circulating dryer 6 at 10 ° C. for 10 minutes. The moisture content (residual moisture content) of this product was measured by the following method.

The moisture content of the carpet immediately after drying was 10 ×
After cutting to 10 cm and measuring the weight (A), 140 ° C
Weight after drying in a hot air circulating drier for 45 minutes and taking out and cooling to room temperature in a desiccator (B)
Was measured and determined by the following equation. Water content (%) = (AB) ÷ A × 100

(Caster test) 5 tile carpets
Cut to size of 00 × 500mm, JIS; L190
According to 4-5, R100,
The test was performed under the condition of 5000 rotations under a load of 90 kg, and the dimensional change rate of elongation with respect to the original size was confirmed. The dimensional change rate of elongation was obtained by measuring the dimensional change rate (H) in the vertical direction and the dimensional change rate (W) in the horizontal direction, and calculating the average ((H + W) ÷ 2). The dimensional change is preferably 0.1% or less for practical use.

(Low Temperature Bending Test) A tile carpet cut to a size of 500 × 500 mm was placed in a 5 ° C.
Left for 4 hours. Immediately after the removal, a steel rod having a diameter of 50 mm was applied to substantially the center of the carpet base material surface, and the backing material surface was bent 180 ° with the backing material surface outside, and the presence or absence of cracks in the backing material was checked by visual inspection.

Then, the result is evaluated as follows,
The results are shown in Tables 1 and 2. ◎: No cracks in the backing material ○: One to several small cracks in the backing material △: 10 or more small cracks in the backing material ×: Cracking of the backing material

Further, only the backing material slurry was hardened by the present manufacturing method without using the carpet base material, thereby producing a backing material sheet. This backing material sheet was punched into a dumbbell-shaped test piece No. 2 shape specified in JIS; K6301. And with a tensile tester, 20 minutes per minute
The film was pulled at a speed of 0 mm, and the tensile strength of the backing material was measured. Table 1 shows the results of Example 1.

Examples 2-7, Comparative Examples 1-4 Tile carpets were manufactured by changing the composition of the backing material slurry and the drying method. Drying time and moisture content of the backing material, caster test, low temperature bending test, backing material Was evaluated for tensile strength. Tables 1 and 2 show the results.

In both tables, “Sumikaflex S-401” of the resin aqueous dispersion is the glass transition point Tg.
Is an ethylene / vinyl acetate copolymer emulsion at −18 ° C. The materials of the backing material slurry such as the aqueous resin dispersion and the hydraulic inorganic powder are shown in parts by weight. Also,
Notes 1 and 2 in Table 2 are as follows. Note 1: Backing material adheres to the belt due to insufficient drying.
Tile carpet cannot be made. Note 2: Cracking and drying shrinkage are large.

As can be seen from the above tables, according to Examples 1 to 7 of the present invention, it is possible to obtain a carpet having sufficient strength and flexibility (based on a low-frequency bending test), It can be seen that the curing time can be reduced.

[0052]

[Table 1]

[0053]

[Table 2]

[0054]

According to the present invention, it is possible to provide a carpet having a sufficient strength and a flexible carpet, and a carpet manufacturing method capable of shortening the drying and curing time. .

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a method for manufacturing a carpet in an embodiment.

FIG. 2 is an explanatory diagram of a carpet in the embodiment.

[Explanation of symbols]

 1. . . Carpet, 10 . . Laminate, 12. . . Carpet substrate, 21. . . First backing material slurry, 22. . . 4. second backing material slurry; . . Electric heater, 55. . . Conveyor belt, 6. . . Hot air circulation type dryer,

Claims (5)

[Claims] 1. A backing material slurry formed of a cement composition comprising a hydraulic inorganic powder containing 4 to 25% by weight of alumina cement and an aqueous resin dispersion is formed into a sheet, and then obtained. The carpet base material is superimposed on the sheet-like material thus formed to form a laminate, and then the laminate is heated from the lower side of the sheet while being moved on the heating unit, and dried and cured to form a carpet. A method for producing a carpet, characterized in that carpet is continuously produced. 2. The method for manufacturing a carpet according to claim 1, wherein the carpet is continuously fed into a drier during the drying and curing to be dried and cured. 3. The resin composition according to claim 1, wherein the resin component in the aqueous resin dispersion is 25 to 200 parts by weight based on 100 parts by weight of the hydraulic inorganic powder. Carpet manufacturing method. 4. The method according to claim 1, wherein:
A method for producing a carpet, wherein the glass transition point of the aqueous resin dispersion is -40C to 5C. 5. The method according to claim 1, wherein:
A method for producing a carpet, characterized in that the set retarder added to the backing material slurry is at least one of gluconic acid, gluconate, citric acid, and citrate.