JPH084549B2 - Carpet manufacturing method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a carpet that exhibits good dimensional stability against changes in ambient temperature.

[Prior Art] A carpet is basically composed of an original carpet and a backing material formed on the back surface thereof. As such a backing material, conventionally, a material containing vinyl chloride resin or asphalt as a main component and an inorganic filler, a plasticizer or the like mixed therein has been used. However, vinyl chloride resin-based ones have the drawback of producing a large amount of smoke during a fire, while asphalt-based ones have problems with odor and weak strength, and the development of new alternative backing materials is desired. It was

Compared to vinyl chloride resin-based materials, these new alternative backing materials emit less smoke during a fire,
Further, those using an ethylene copolymer resin composition containing an inorganic filler, which is non-toxic, odorless, and has high strength, have been noted and have begun to be studied.

[Problems to be Solved by the Invention] However, when a carpet having a simple structure is manufactured by using such a backing material, the dimensional stability is not always good, so that it is not particularly satisfactory for tile carpets. There wasn't.

By the way, the tile carpet is generally a small flat plate-like carpet, and generally has a square shape with one side of 30 to 50 cm. Compared to normal carpet, tile carpet
It is easy to handle and lay, and it has the advantage that it can be easily partially replaced due to dirt or the like. Further, since it has the advantage that various patterns can be revealed by combining the colors and shapes of several kinds of tile carpets, it has been rapidly used recently. Most of this tile carpet has a construction method in which it is completely spread from wall to wall,
Therefore, unless dimensional changes due to temperature differences are reduced as much as possible, for example, things constructed in the winter may expand and rise in the summer, or those constructed in the summer may shrink and form gaps in the winter. Could occur.

In order to improve such a defect, for example, JP-A-61-61
Japanese Patent Laid-Open No. 19886 discloses a method of using a mesh-like base cloth having a small coefficient of linear expansion with respect to heat between the original carpet and the backing material. However, according to the study of the present inventors, when a mesh-like base cloth having a large openness as disclosed in this publication is used, it is confirmed that the dimensional stability is sufficiently satisfactory. I admitted that it wouldn't be. Further, Japanese Patent Laid-Open No. 61-19887 proposes a method in which the backing material layer is divided into two layers and an intermediate base cloth having a small linear expansion coefficient against heat is provided between them. However, this method requires the backing material to be laminated on the carpet base material twice, which is an economically disadvantageous method from the viewpoint of both the apparatus and the operation.

The present inventors have studied a method for improving the above-mentioned drawbacks in the prior art and economically producing a carpet having excellent dimensional stability and strength, particularly a tile carpet. As a result, they have found a method capable of producing a desired carpet in one step by using an ethylene copolymer resin-based thermal adhesive film and a glass nonwoven fabric.

[Means for Solving the Problems] According to the present invention, (a) an ethylene copolymer resin-based thermal adhesive film having a basis weight of 10 to 200 g / m ² is provided on the back surface of the original carpet (b) a basis weight of 10 ~ 300 g / m ² of glass non-woven fabric are superposed in this order, and (c) the ethylene filler-containing ethylene copolymer resin composition is continuously melt extruded from the extruder as a sheet having a basis weight of 1 to 5 kg / m ^2. Then, a method for producing a carpet is provided, which comprises stacking the laminate on a glass nonwoven fabric surface, pressing the sheet while the sheet is hot, and pressing the sheet when the sheet is hot to integrate them.

In the present invention, as the original carpet, those manufactured from various materials such as natural fiber, synthetic fiber and recycled fiber can be used. More specifically, natural fibers such as hemp, cotton and wool, polypropylene, polyamide, polyester,
Examples include tufted carpets and needle punched carpets made of synthetic fibers such as polyacrylonitrile and polyvinylidene chloride. A precoat treatment such as SBR latex treatment may be performed on the back side of the original carpet.

In the present invention, in order to firmly bond the back surface of the original carpet and the glass nonwoven fabric (b), the basis weight is 10 to 20.
A 0 g / m ² ethylene copolymer resin-based thermal adhesive film (a) is used. This ethylene copolymer resin has ethylene as a main component and α-olefin, a polar vinyl compound, etc. as a copolymerization component, and is melted by the heat held by the melt extruded sheet of the component (c) described later. , Acts as an adhesive. More specifically, the α-
As the olefin, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene,
1-decene, 4-methyl-1-pentene and the like, and polar vinyl compounds include vinyl esters such as vinyl acetate and vinyl propionate, unsaturated carboxylic acids such as acrylic acid, methacrylic acid, fumaric acid and maleic anhydride. , Or their anhydrides, such as their sodium salts, potassium salts, lithium salts, magnesium salts, zinc salts, ammonium salts, unsaturated carboxylic acid salts, methyl acrylate, ethyl acrylate, isobutyl acrylate, acrylic acid n. −
Examples thereof include unsaturated carboxylic acid esters such as butyl, methyl methacrylate, and glycidyl methacrylate.

Of course, two or more kinds of these copolymerization components may be copolymerized. These copolymerization components may be randomly copolymerized or graft copolymerized.

In the ethylene-α-olefin copolymer resin, it is preferable that ethylene contains about 80 to 95 mol%, and in the ethylene-polar vinyl compound copolymer, ethylene is 55 to 95% by weight. % Is preferable. Two or more kinds of these copolymer resins may be used in combination.

From the viewpoint of the adhesiveness to carpets and glass fibers or the productivity of the film, a preferred ethylene copolymer resin is an ethylene-polar vinyl compound copolymer, especially an ethylene-vinyl acetate copolymer, and its ethylene content is 70- 95% by weight. Also, 190 ℃, 2
Melt flow rate measured with 160g load is 0.1-200g / 10
Minutes, especially 1 to 100 g / 10 minutes are suitable.

These ethylene copolymer resins include aliphatic hydrocarbon resins, alicyclic hydrocarbon resins, aromatic hydrocarbon resins, polyterpene resins, rosins, and styrene resins for the purpose of improving thermal adhesion and the like. Such tackifiers may be blended and used in an amount of up to 25% by weight, for example. Further, a slip agent for improving the slip property of the film and other various additives can be blended.

The thermal adhesive film is used in such an amount that the basis weight is 10 to 200 g / m ² , preferably 15 to 100 g / m ² . If the basis weight is less than the above range, the adhesive force between the carpet original fabric and the glass nonwoven fabric is insufficient, and if the basis weight is too large, the heat retained by the melt-extruded sheet of component (c) is sufficient. It does not melt and becomes difficult to function as an adhesive.

In the present invention, the glass nonwoven fabric (b) is used in order to impart dimensional stability to the carpet. A glass nonwoven fabric is made by stacking glass fibers in a certain direction in a certain thickness and hardening them with a coagulant, and the basis weight is 10 to 300 g.
/ m ² , preferably about 30 to 150 g / m ² is used. If the basis weight is too small, good dimensional stability cannot be obtained,
On the other hand, if the weight per unit area is too large, the carpet tends to be too rigid, so that a suitable range should be selected and used.

In the method disclosed in JP-A-61-19886,
A mesh-like base fabric having a porosity necessary for passing a backing material is used, but a non-woven fabric subjected to perforation treatment having such a high porosity is used, or a woven fabric is used. Therefore, a carpet having excellent dimensional stability cannot be obtained.

In the present invention, the respective layers constituting the carpet are integrated by utilizing the adhesiveness of the component (c) melt-extruded into a sheet and the adhesiveness of the component (a) melted by the heat held by the component (c). Since the component (c) does not need to pass through the glass nonwoven fabric, the glass nonwoven fabric used in the present invention, on the contrary, has a small porosity, and the component (c) is substantially the component (a) during molding of the carpet. It should not be able to pass through to the side and is virtually unperforated. Since such a glass nonwoven fabric having a low porosity is used, the dimensional stability of the manufactured carpet is significantly improved. In the present invention, an inorganic filler-blended ethylene copolymer resin composition is used as the backing material. The ethylene copolymer resin used for this purpose may be the same as the ethylene copolymer resin described in the component (a). Especially when extruding into a sheet using a T-die,
In order to maintain particularly excellent moldability, the melt flow rate is preferably about 1 to 150 g / 100 minutes, particularly about 1 to 50 g / 10 minutes. From the viewpoints of economy, miscibility with inorganic fillers, flexibility, cold resistance, etc., as an ethylene copolymer resin,
Preference is given to using ethylene-vinyl acetate copolymers. As the suitable copolymer, one having a vinyl acetate content of about 10 to 40% by weight is preferably used in consideration of the above properties and heat resistance. Of course, a part of such ethylene vinyl acetate copolymer, for example, half or less is replaced with another ethylene copolymer resin, for example, ethylene-α-olefin copolymer or ethylene-unsaturated carboxylic acid copolymer. be able to.

As the inorganic filler to be kneaded with the ethylene copolymer resin, calcium carbonate, barium sulfate, silica, talc,
Clay, mica, magnesium hydroxide, aluminum hydroxide and the like are used. These are used for the purpose of cost reduction, weight impartment, dimensional stability, etc. From the viewpoint of cost or miscibility with ethylene copolymer resin, calcium carbonate is particularly preferable. To achieve the above object, the amount of the inorganic filler used in the ethylene copolymer resin composition is at least 20% by weight, preferably 30% by weight or more.
It is desirable to set the content to 80% by weight or less, but if the blending amount is increased too much, the sheet formability will deteriorate.

The content of the ethylene copolymer resin in the composition is preferably 20 to 80% by weight, particularly 30 to 80% by weight, but it is easy to mix with the inorganic filler or the sheet moldability of the composition is improved. In order to do so, the tackifier, wax, low molecular weight olefin polymer, liquid plasticizer, oil and the like as exemplified above can be used in place of a part of the ethylene copolymer resin. These processability-improving additives are used, for example, in an amount of 20% by weight or less based on the entire composition. Additives such as various stabilizers, flame retardants and pigments may be appropriately added to the ethylene copolymer resin composition.

The method of blending the ethylene copolymer resin with the inorganic filler is not particularly limited. By blending the powdery inorganic filler and the ethylene copolymer resin directly with a calendar roll, Banbury mixer, Henschel mixer, twin-screw kneader, etc., the composition of the pelletized ethylene copolymer resin and the inorganic filler is compounded. Create an object and use it to create a T-
Die extrusion method. Further, the powdered inorganic filler and the processability improving additive are mixed by using a Banbury mixer, a twin-screw kneader or the like to form a pellet-shaped master batch of the high-concentration inorganic filler, and the pellets and ethylene are mixed. There is a method of using the copolymer resin by dry blending it directly at an arbitrary ratio during T-die extrusion.

Sheet forming is performed by a T-die extruder. At this time, the basis weight of the sheet is 1 kg / m ^{2 in} order to add weight to the tile carpet and prevent it from moving during walking.
Although it is preferable that the amount is 5 kg / m ² or less, if the basis weight is too large, the amount becomes too rigid and the workability deteriorates.

In the present invention, the above-mentioned ethylene copolymer resin-based heat-adhesive film and glass non-woven fabric are superposed in this order on the back surface of the original carpet, and the inorganic filler-containing ethylene copolymer resin composition is continuously formed into a sheet from an extruder. Melt-extruded and laminated on the glass nonwoven fabric surface of the laminate, pressed while the melt-extruded sheet is hot, and melt-bonding action of the sheet and the ethylene-copolymer resin-based heat-adhesive film by the heat held by the sheet By this, each layer constituting the carpet is integrated. The press integration is preferably performed by passing it through a pressure roll. At this time, it is necessary to select such conditions that the heat-adhesive film is melted and that the layers are adhered to each other and integrated by pressing. For that purpose, the temperature at which the extruded sheet in the pressing portion is in a softened state, for example, 100 to 200 ° C., may be maintained, and the pressure roll may be maintained at a linear pressure of 2 to 10 kg / cm ³ .

In the present invention, by laminating and pressing the layers constituting the carpet when the melt extruded sheet is hot, the melt adhesiveness of the sheet is utilized, and an ethylene-based heat-adhesive film is formed by the heat held by the sheet. Since they are melted and used as an adhesive to integrate them at the same time, a carpet can be manufactured in one step. Instead of such a one-step process, using a method of coating the backside of the original carpet with an ethylene-based heat-adhesive film not only complicates the process but also tensions the carpet, which is rather dimensionally stable. It is not a preferable method because it deteriorates the sex.

As described above, after the press-integration, the tile carpet can be manufactured by cooling if necessary and then cutting into a desired shape.

[Examples] The present invention will be specifically described below with reference to Examples and Comparative Examples.

Example 1 Polyethylene wax (hereinafter abbreviated as PEWAX) (density
0.93 g / cm ³ , molecular weight 4000) 10 parts, atactic polypropylene (abbreviated as APP below) (density 0.87 g / cm ³ , molecular weight 30000) 10 parts, calcium stearate 0.2 parts and calcium carbonate 80 parts Banbury Temperature with mixer
After melt-mixing under the condition of 125 ° C., the melt-mixture was discharged through an extruder to be pelletized to obtain a pellet-shaped mixture of high-concentration calcium carbonate. (Hereinafter Ca
Abbreviated as CO ₃ MB. ) Next, EVAflex P3307 (Mitsui
EVA manufactured by DuPont Poly Chemical Co., vinyl acetate content 33
% By weight, MFR 30 g / 10 min) 40 parts by weight and CaCO ₃ MB 60 parts by weight, and a mixture obtained by dry blending the T-
Using a 65 mm extruder (L / D = 24) equipped with a die, under the processing conditions of a T-die temperature of 150 ° C., a sheet of calcium carbonate-containing EVA having a width of 600 mm and a basis weight of 2.6 kg / m ² is formed, Further, before the sheet is cooled and solidified, from the upper part of the T-die, a carpet original fabric (nylon pile, first base cloth) and Everflex P.
30 basis weight of 1905 (EVA manufactured by Mitsui DuPont Polychemical Co., Ltd., vinyl acetate content 19% by weight, MFR 2.5 g / 10 minutes)
A three-layered structure in which a g / m ² film and a glass non-woven fabric (weight per unit area of 45 g / m ² ) were superposed on each other so that the glass non-woven fabric surface was in contact with the calcium carbonate-containing EVA sheet surface. , Created a tile carpet stock.

Furthermore, after the raw fabric of the tile carpet was cut into a size of 500 mm × 500 mm, the following physical properties were evaluated.

(1) Dimensional stability In the vertical direction of the tile carpet (flow direction of the T-die sheet) and in the horizontal direction (direction perpendicular to the flow direction of the T-die sheet), three standard lines are set at 23 ° C. Pull and measure the dimension up to 0.05 mm. After this, 60
It is left for 2 hours in a hot air circulation dryer at 0 ° C, and then immersed in water at 20 ° C containing 0.1% of a nonionic activator. After 2 hours, take out from the water column, drain the water, and leave the test piece dried in a dryer at 60 ° C for 24 hours in the standard state for 24 hours to measure the dimensions. The change in the dimension when not treated and the dimension after treatment is displayed in%.

(2) Pull-out strength Using a normal tensile tester, 23 ℃, pulling speed 200mm / min
The yarn pull-out strength of the pile was measured under the conditions of.

 The evaluation results are shown in Table-1.

The thermal adhesive film layer was the first layer and the T-die sheet layer was the second layer.

Example 2 In Example 1, the basis weight of the heat-adhesive film was 100 g / m.
^A carpet was manufactured and evaluated in exactly the same manner as in Example 1 except that the value was changed to ² . The results are shown in Table-1.

Example 3 In Example 1, the type of the heat-adhesive film was Evaflex V-340 (E manufactured by Mitsui DuPont Polychemical Co., Ltd.).
A carpet was produced and evaluated in exactly the same manner as in Example 1, except that the VA and vinyl acetate content were 10 wt% MFR 1.9 g / 10 minutes). The results are shown in Table-1.

Example 4 In Example 1, the type of the heat-adhesive film was changed to ethylene-methacrylic acid copolymer resin, Nucrel 925 (Mitsui DuPont Polychemical Co., Ltd., MFR 25g / 10 minutes, methacrylic acid content 15wt%). A carpet was manufactured and evaluated in exactly the same manner as in Example 1 except that it was changed. The results are shown in Table-1.

Example 5 In Example 1, the type of the heat-adhesive film was changed to ethylene-ethyl acrylate copolymer resin, Evaflex.
EEA A702 (Mitsui DuPont Polychemical Co., Ltd., M.
A carpet was manufactured and evaluated in exactly the same manner as in Example 1 except that the FR was changed to 5 g / 10 min ethyl acrylate content 19 wt%). The results are shown in Table-1.

Example 6 In Example-1, the types of heat-adhesive films were Evaflex V-340 85 wt% and hydrocarbon-based adhesive FTR-
6100 (Mitsui Petrochemical Industry Co., Ltd., softening point 97 ° C) 15 wt%
A carpet was manufactured and evaluated in exactly the same manner as in Example 1 except that the composition was changed to. The results are shown in Table-1.

Example 7 In Example 1, the type of glass non-woven fabric was changed to a weight per unit area of 20.
A carpet was manufactured and evaluated in exactly the same manner as in Example except that the value was changed to 0 g / m ² . This result is shown in the table −
It is shown in FIG.

Example 8 The ratio of EVA and CaCO ₃ MB of the second layer in Example 1 was set to EV.
A, 60 wt% CaCO ₃ MB 40 wt% The carpet was manufactured and evaluated in exactly the same manner as in Example 1 except that it was changed to 40 wt%. The results are shown in Table-1.

Example 9 In Example 1, the second layer is a mixture of EVA, process oil and calcium carbonate Keldax 6826 (Dupont, USA).
A carpet was produced and evaluated in exactly the same manner as in Example 1 except that calcium carbonate content (72 wt%, MFR, 3 g / 10 minutes) manufactured by the same company was used. The results are shown in Table-1.

Comparative Example 1 A carpet was manufactured and evaluated in the same manner as in Example 1 except that the first layer was not used.
The results are shown in Table-2.

Comparative Example 2 In Example 1, the high pressure low density polyethylene (Mirason M-68 (MFR23g, manufactured by Mitsui Oil Industry Co., Ltd.) was used as the first layer.
/ 10 minutes, density 0.916g / cm ³ ··· Hereinafter abbreviated as LDPE. A carpet was manufactured and evaluated in exactly the same manner as in Example 1 except that the value was changed to). The results are shown in Table-2.

Comparative Example 3 In Example 1, except that the glass nonwoven fabric was not used,
Carpets were manufactured and evaluated in exactly the same manner as in Example 1. The results are shown in Table-2.

[Advantage of the Invention] According to the present invention, a carpet original sheet is placed on a sheet of the melt-extruded inorganic filler-blended ethylene copolymer resin composition,
A tile carpet having good dimensional stability, strength, interlayer adhesion and the like can be produced by a simple operation of superposing an ethylene-based heat-adhesive film and a glass nonwoven fabric and pressing the sheet while it is hot.

Claims (1)

[Claims] 1. A carpet on the rear surface of the raw (a) mass per unit area that order a is 10 to 200 g / m ² of ethylene copolymer resin based heat adhesive film (b) weight per unit area of 10 to 300 g / m ² nonwoven glass fabric And (c) the inorganic filler-blended ethylene copolymer resin composition is melt-extruded continuously from an extruder as a sheet having a basis weight of 1 to 5 kg / m ² and laminated on the glass nonwoven fabric surface of the laminate. A method for manufacturing a carpet, characterized in that the sheets are pressed and integrated when they are hot.