JPH0319980A - Highly foaming aqueous adhesive composition for carpet and carpet prepared by coating therewith - Google Patents

Abstract

PURPOSE:To obtain the subject adhesive composition, containing an aqueous latex, foaming agent, inorganic filler and thickener as essential components, having high bonding strength and capable of exhibiting an excellent foaming ratio. CONSTITUTION:A highly foaming aqueous adhesive composition, obtained by blending (A) an aqueous latex (e.g. styrene-butadiene copolymer latex) with (B) a foaming agent, e.g. a laurate or nonionic surfactant, (C) an inorganic filler, e.g. calcium carbonate, and (D) a thickener, such as an acrylate, as essential components and foaming the resultant blend so as to provide 2-4 times foaming ratio and useful for carpets. The above-mentioned composition exhibits a high bonding strength of >=25kg/cm<2> maximum tension of a dried film prepared by defoaming treatment thereof. The aforementioned adhesive composition can be applied to a carpet base material to mass-produce a lightweight carpet of high merchandise value with high adhesion at a low cost.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention provides a novel high foaming water-based adhesive composition for carpets,
and a carpet formed by coating the same. More specifically, the present invention maintains high adhesive strength, significantly increases the foaming ratio, and reduces the coating weight of the carpet, thereby improving the handleability and productivity of the carpet. The present invention relates to a highly foaming water-based adhesive composition for carpets that enables cost reduction, and to carpets coated with this composition.

BACKGROUND OF THE INVENTION Conventionally, carpets are usually coated with a water-based adhesive composition to fill in the irregularities of the raw material. This aqueous adhesive composition generally includes a dispersant, an anti-aging agent, a preservative, an antifoaming agent, a crosslinking agent,
After adding an anti-blister agent, an inorganic filler, and a thickener to adjust the viscosity to a level suitable for flow processability, it is applied directly (without foaming) to uneven carpet raw material using a coater. It is being worked on.

However, in such a method, a large amount of water-based adhesive Il is required to fill in the unevenness of the raw carpet material, and this tendency is particularly large in the case of raw carpet material with a large pile. If the coating weight is large, the overall weight of the carpet becomes heavy, resulting in problems such as poor handling, an inevitable increase in cost, and a decrease in productivity.

Therefore, as a method of reducing the coating weight of the water-based adhesive ml material, air is forcibly mixed into the composition by mechanical stirring to increase the capacity and reduce the coating weight of the uneven carpet material. A foaming (cross) coating method (Japanese Patent Publication No. 48-9829) that reduces foaming has attracted attention, and a water-based carpet adhesive composition effective for such foaming coating method (Japanese Patent Application Laid-open No. 63-227875) Public bulletins) have also been proposed.

However, in conventional water-based adhesive compositions, when the foaming ratio is increased, the cohesive force of the adhesive layer decreases when applied to carpet, and the adhesive strength such as pile pull-out strength and peel strength decreases. The disadvantage is that it cannot be avoided. For example, in the above-mentioned Japanese Patent Publication No. 48-9829, in the examples, the foaming ratio is 1.7 to 3 times (specific gravity 0.85 to 0.
．． 50) A carpet coated with a foamed aqueous adhesive composition is shown, but a secondary base fabric is laminated to obtain the desired adhesive strength! In addition, the foaming ratio of the composition was kept low at 1.7 times, and the coating amount was 9699/II.
1" is used in large quantities.

As described above, in the conventional foaming coating method, in order to obtain the desired adhesive strength, it is not possible to increase the foaming ratio of the water-based adhesive composition, and the foaming ratio is 1.1 to 2.0 at most. As a result, the coating amount of the water-based adhesive composition can only be reduced by about 2/3, making it difficult to expect cost reductions and productivity increases. The reality is that the effects have not improved.

Problems to be Solved by the Invention The present invention overcomes the drawbacks in the prior art, and
A product for carpets that maintains high adhesive strength, significantly increases the foaming ratio, and reduces the coating weight of carpets, improving carpet handling and productivity, and making it possible to significantly reduce costs. This work has been made for the purpose of providing a highly foaming water-based adhesive composition and a carpet coated with this composition.

Means for Solving the Problems In order to achieve the above-mentioned object, the present inventors have conducted extensive research and found that the maximum tensile strength of the dry film obtained by defoaming is within a specific range, and We have discovered that this objective can be achieved by using a highly foaming aqueous adhesive composition that is foamed to a foaming ratio of 100. Based on this knowledge, we have completed the present invention.

That is, the present invention contains (A) an aqueous latex, (B) a foaming agent, (C) an inorganic filler, and (D) a thickener as essential components, and a dry film obtained by defoaming treatment. A highly foaming water-based adhesive composition for carpets, which has a maximum tensile strength of 25k97 cm" or more and is foamed to have a foaming ratio of 2.0 to 4.0 times, and this composition. The purpose is to provide a carpet that is coated on raw carpet material.

The present invention will be explained in detail below.

In the composition of the present invention, in the aqueous latex used as the Iffi component (A), the glass transition temperature of the polymer is preferably in the range of -30 to +40°C. If the glass transition temperature is less than -30°C, the maximum tensile strength of the dry film of the composite will not be high, and the adhesive strength of the carpet will be insufficient; if it exceeds 40°C, the resulting carpet will have a hard texture. This is not desirable.

In addition, the content of toluene insoluble matter in the polymer is
The content is desirably 50% by weight or more, both when no crosslinking agent is added and after crosslinking with the addition of a crosslinking agent and heat treatment. The content of this toluene insoluble matter is 5
If it is less than 0% by weight, the maximum tensile strength of the dry film of the composite will be low and sufficient adhesive strength will not be obtained. It is desirable that the content of this toluene-insoluble matter be higher when a polymer having a low glass transition temperature is used.

Examples of the aqueous latex include styrene-butadiene copolymer latex, methyl methacrylate-butadiene copolymer latex, styrene-butadiene-methyl methacrylate copolymer latex, styrene-butadiene-butyl acrylate copolymer latex, and styrene-butyl acrylate. Examples include copolymer latex, acrylonitrile-butadiene copolymer latex, and ethylene-vinyl acetate copolymer latex. Furthermore, a latex in which the copolymer contains a monomer unit having an active group such as a carpoxyl group, a glycidyl group, an amide group, a hydroxyl group, or an N-methylol group can also be used. Among these latex,
Particularly suitable are carboxy-modified styrene-butadiene copolymer latex and carboxy-modified styrene-butadiene-methyl methacrylate copolymer latex. These aqueous latexes may be used alone or in combination of two or more.

Among the aqueous latexes, examples of polymers whose glass transition temperature is in the range of -10 to +35°C include styrene-ptadiene copolymer latex.
Examples include copolymers containing about 25 to 45% by weight of butadiene units.

In the composition of the present invention, examples of the foaming agent used as the Iffi component (B) include sodium lauryl sulfate,
Alkyl sulfate salts such as potassium lauryl sulfate, ammonium lauryl sulfate, triethanolamine lauryl sulfate, sodium myristyl sulfate, sodium capryl sulfate, polyoxyethylene sodium lauryl sulfate, polyoxyethylene ammonium lauryl sulfate, polyoxyethylene lauryl triethanolamine, poly Alkyl ether sulfates such as sodium oxyethylene oleyl ether sulfate, polyoxyethylene myristyl ether sulfate triethanolamine, alkyl benzene sulfonates, alkylna-7-talene sulfonates,
Sulfonate salts such as alkyl sulfosuccinates and alkyldiphenyl ether disulfonates, fatty acid salts such as sodium stearate, ammonium stearate, sodium myristate, potassium olelyate, potassium balmitate, and ammonium laurate, or alkyl phosphates. Anionic surfactants such as salts,
Nonionic surfactants such as holoxyethylene nonylphenyl ether, polyoxyethylene dodecylphenyl ether, lauric acid monoethanolamide, stearic acid monoethanolamide, lauric acid impropanolamide, coconut oil fatty acid diethanolamide, and even betaine Examples include amphoteric surfactants such as amine-based surfactants and cationic surfactants such as amine-based surfactants. These foaming agents may be used alone or in combination of two or more. This foaming agent is used during the production of the aqueous latex of the component (A), and may be used as it is contained in the aqueous latex, or may be added when preparing the composition. It's okay.

Regarding the amount of foaming agent added, the more the inorganic filler (C) component is added, the more the amount of foaming agent adsorbed to the filler increases. , it is necessary to increase the amount of the foaming agent added. Furthermore, compared to the amount of foaming agent in adhesive compositions used in conventional foaming coating methods, the amount of foaming agent used in the composition of the present invention has a significant effect on foaming properties and foaming stability. It is advantageous to increase from the top.

In the composite of the present invention, examples of the inorganic filler used as component (C) include calcium carbonate, aluminum hydroxide, magnesium hydroxide, clay, titanium oxide, and barium sulfate. These inorganic fillers may be used alone or in combination of two or more.

Regarding the blending amount of this inorganic filler, it is desirable that the blending ratio with the aqueous latex of component (A) be close to the critical filler volume concentration (PVC), and the filler volume concentration will be in the range of 35 to 60%. It is preferable to mix them in such a manner. Amounts in this range can be used, for example, as an inorganic filler.
When using commonly used heavy calcium carbonate, it corresponds to 150 to 400 parts by weight per 100 parts by weight of aqueous latex.

If the volume concentration is less than 35%, the blister resistance will be poor and it will be economically disadvantageous, and if it exceeds 60%, the cohesive force of the adhesive composition will decrease, and the adhesive strength of Rikiichipet will decrease. Therefore, it is not desirable.

Further, in the composition of the present invention, examples of thickeners used as component (D) include sodium acrylate,
Examples include water-soluble polymer compounds such as canoleboxymethylcellulose, hydroxymethylcellulose, methylcellulose, polyacrylamide, polyvinyl alcohol, polyvinylpyrrolidone, and blocked alkyl polyether. These thickeners may be used singly or in combination of two or more.

In the composition of the present invention, a crosslinking agent may be added as desired for the purpose of increasing the maximum tensile strength of the dry film and improving adhesive strength. The addition of this crosslinking agent is particularly effective for aqueous latexes having active groups in their polymers, since the crosslinking agent reacts with and crosslinks the polymers of the aqueous latex.

Examples of such crosslinking agents include ethylene glycol diglycidyl ether, brobylene glycol diglycidyl ether, glycerin diglycidyl ether, N,
Compounds with two or more glycidyl groups such as N,N',N'-tetraglycidyl m-xylene diamine, ■,3-bis(N,N-diglycidylaminomethyl)cyclohexane, di7enylmethane bis-4 .4'-N. N'-
Compounds having an ethyleneimine group such as diethylene urea, p-7 22lenebis-N,N'-ethyleneurea, m-tolylenebis-N,N'-ethyleneurea, and compounds having an incyanate group such as blocked isocyanate, modified Examples include polyamide resins, oxazoline compounds, and compounds having a methylol group. One type of these crosslinking agents may be used, or two or more types may be used in combination.

In the highly foaming water-based adhesive composition of the present invention, the maximum tensile strength of the dry film obtained by defoaming treatment is 25 kg/cm.
It is necessary that it is above. The maximum tensile strength of the dried film of the water-based adhesive composition conventionally used for carpets is usually about 10 to 20 k9/cra", and 25 ke/cm.
``The above materials were rarely used because the texture was too hard due to the amount of coating applied.

In the present invention, the maximum tensile strength of the dry film is 25 kg/cm.
``If this is the case, even if the foam is foamed at a high foaming ratio, the cohesive force of the adhesive layer of the carpet will be maintained, and the amount of coating can be significantly reduced without reducing the adhesive strength. The texture of the film can also maintain appropriate softness.The method for measuring the maximum tensile strength of the dry film will be explained later.

If the maximum tensile strength of this dry film is less than 25 kg/cry, when it is applied to raw carpet material in a highly foamed state, the cohesive force of the adhesive layer after drying will be low and sufficient adhesive strength will not be obtained, making it impractical for practical use. Not.

The composition of the present invention needs to be foamed so that the foaming ratio is in the range of 2.0 to 4.0 times, preferably 2.5 to 3.5 times. If this foaming ratio is less than 2.0 times, it is easy to increase the adhesive strength of the carpet, but the effect of reducing carpet costs and improving productivity will not be fully demonstrated, and if it exceeds 4.0 times, the adhesive strength of the carpet will be increased. There is a tendency for the cohesive force of the adhesive layer to decrease and the adhesive strength to decrease.

When the foaming ratio is increased from 2.0 to 4.0 times, the coating weight will be relatively 2/2 of the normal amount even when coating uneven carpet raw material.
As a result, the drying speed can be reduced by 1.3 to 1/3.
It can be increased by 5 to 3.0 times. The reason why the coating weight is not inversely proportional to the foaming ratio is that when coating raw carpet material,
This is because foaming of the aqueous adhesive occurs, resulting in a decrease in capacity.

There are no particular restrictions on the method of foaming the composite, and any method conventionally used for foaming water-based adhesives can be used, such as using a so-called 7-loss machine.
The ratio of the supply capacity of the composite to the air capacity may be appropriately selected so that the foaming ratio is in the range of 2.0 to 4.0 times, and air may be mechanically mixed to foam the foam. .

The highly foaming water-based adhesive composition for carpets of the present invention may contain, as necessary, a dispersant, an antifoaming agent, a flame retardant, an anti-aging agent, an antistatic agent, etc., as long as the object of the present invention is not impaired. agent,
Antibacterial/antifungal agents, pHI adjusters, chelating agents, anti-blister agents, waterproofing agents, etc. may be added. However, it is desirable to avoid using antifoaming agents as much as possible. If the amount added is too large, foaming properties may be impaired. Regarding the anti-blister agent, since the composition of the present invention has a high foaming ratio, it is not necessary so much, but in the case of a low solid content and a low foaming ratio, it is better to add it to prevent the occurrence of blistering,
This is advantageous because productivity can be increased.

In the composite of the present invention, the viscosity before foaming at room temperature is 1
5000" 40000cps1 preferably 20000
It is desirable to be in the range of ~35,000. If the viscosity before foaming is less than 15,000 cps, the penetration into the raw carpet material will be large and the foaming property will be poor;
If it exceeds s, the fluidity decreases and uneven coating tends to occur, and the air pressure supplied to the foaming device becomes too high, making it difficult to achieve the desired foaming ratio.

Further, the solid content in the composition is usually selected in the range of 60 to 85% by weight, preferably 65 to 83% by weight.

If the solids content is less than 60% by weight, there will be too much moisture, resulting in low drying efficiency and poor carpet productivity; if it exceeds 85% by weight, it will be difficult to adjust the viscosity, and in some cases the composition will thicken. This is undesirable since foaming is not possible due to the foaming process and stiffness and uneven coating are likely to occur.

By applying such a highly foaming water-based adhesive composition to raw carpet material, the carpet of the present invention with high adhesive strength can be obtained.

There are no particular restrictions on the method of coating the composite, and any method conventionally used for coating raw carpet materials can be used. For example, it may be applied using a normal roll coater, it may be applied directly to the raw carpet material, and any of the methods such as single coating method, double coating method, double separation coating method, etc. can be used. .

Furthermore, regarding the coating weight, the type of raw carpet material (
Since the degree of unevenness of the coated surface varies depending on the gauge number, pile height, basis weight, etc., it cannot be determined unconditionally, but when comparing the same raw carpet material, the high foaming water-based adhesive of the present invention The composition is 2/2 compared to the composition before foaming.
You only need about 3 to 1/3 of the amount.

Effects of the Invention The highly foaming water-based adhesive composition for carpets of the present invention has high adhesive strength and greatly increases foaming properties, reducing the weight of coating on carpets. It has the characteristics that it can improve the handling and productivity of the carpet, and can significantly reduce the cost. has high commercial value as it is lightweight and has high adhesive strength.

EXAMPLES Next, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples in any way.

In addition, each characteristic in an Example and a comparative example was calculated|required according to the method shown below.

(+) Maximum tensile strength of dry film After depressurizing the water-based adhesive composition to -730m+II}Ig or less and degassing, the clearance on the Teflon plate is 1m.
It was cast with a 23 m applicator at a temperature of 23°C and a relative humidity of 6.
Dry for 1 day or more under 0% conditions. This dried film was heat-treated at 90°C for 15 minutes, and then further heated at 23°C.
After being left for one day or more under the conditions of ℃ and 60% relative humidity, it is subjected to measurement.

The dried film was made into a tanzak shape with a width of io+++m, and was set in a tensile tester, with a distance between chucks of 50 mm, and a tensile speed of 1.
Measurement is carried out under conditions of 00 mm/minS, temperature of 23° C., and relative humidity of 60%.

(2) Foaming ratio This is the value obtained by dividing the specific gravity of the composite material after foaming by the specific gravity of the composite material before foaming.

(3) Peeling strength, pile pull-out strength After leaving the carpet sample in a constant temperature room at 23°01 60% RH for more than 24 hours, the carpet sample was tested using the carpet test method (JIS
L-1021).

(4) Texture A test piece 10×20C++1 was cut out from the carpet sample, and the long direction of this test piece was bent to create a distance of lOc+i between both ends in the short direction.The bending stress of the carpet was used as a measure of the texture. The larger this value, the
Kazekai means hard.

(5) Viscosity of the composite before foaming (room temperature) Using a Brook 7 yield type rotational viscometer (BM type),
No. The measurement was performed using 4 rotors at a rotation speed of 12 rpm.

Examples 1 to 7, Comparative Examples 1 to 6 To 100 parts by weight of various aqueous latexes obtained from the heptanomer combinations shown in Table 1, foaming agents of the type and amount shown in Table 2 were added, and After adding 1 part by weight of sodium tripolyphosphate as a dispersant, a second layer of heavy calcium carbonate (SS-30, manufactured by Nitto Funka) as an inorganic filler was added.
The amount shown in the table was added.

Then, after the heavy calcium carbonate is sufficiently dispersed,
Add sodium polyacrylate as a thickener in the amount shown in Table 2 to increase the viscosity (room temperature) to 30,000 ± 1,000 cp.
A water-based adhesive composition having the solid content shown in Table 2 was prepared. In addition, 1 part by weight of an anti-aging agent was added to all of the examples, and 1 part by weight of glycerin diglycidyl ether as a crosslinking agent was added to Examples 4 and 5 and Comparative Example 5. Next, using 300 g of the water-based adhesive obtained in this way, air was mechanically mixed and stirred at a rotation speed of 22 Orpm using a tabletop Hobart mixer Model 5SS (manufactured by Hobard, equipped with a whip blade). By adjusting the time, foaming water-based adhesive compositions having foaming ratios shown in Table 2 were obtained.

This foaming water-based adhesive composition was uniformly applied to a raw carpet material made of a primary base fabric of polypropylene tufted with BCF nylon to a coating weight shown in Table 2, and then 7 oz. The secondary base fabric is pasted together, dried at 130°C using a hot air circulation dryer, and dried until the moisture content of the composite becomes 5% by weight or less. I made a curved carpet by coating a paraboloid. In addition, the drying time at this time was determined.

The thus obtained carpet was evaluated for peel strength, pile pull-out strength, and texture. These results are shown in Table 2.

f Type of foaming agent: Sodium lauryl sulfate: Triethanolamine lauryl sulfate: Sodium dodecylbenzenesulfonate: Sodium polyoxyethylene lauryl ether sulfate: Polyoxyethylene lauryl ether sulfate triethanolamine: Polyoxyethylene nonyl phenyl ether

Claims (1)

[Scope of Claims] 1. A dry film containing (A) aqueous latex, (B) a foaming agent, (C) an inorganic filler, and (D) a thickener as essential components and obtained by defoaming treatment. The maximum tensile strength of is 25kg/c
A highly foaming aqueous adhesive composition for carpets, which is foamed to have a foaming ratio of m^2 or more and a foaming ratio of 2.0 to 4.0 times. 2. A carpet obtained by coating raw carpet material with the composition according to claim 1.