JPH06262633A - Manufacture of foam composite body - Google Patents

Abstract

PURPOSE:To obtain composite body consisting of skin material and non-rigid foam in a short time by a method wherein polyurethane foaming mixture is applied on air-permeable and releasable sheet and, within the specified time on and after cream time, the skin material is laminated onto the mixture so as to be subjected to thermal curing treatment. CONSTITUTION:Polyurethane foaming mixture contains polyol, polyisocyanate, catalyst, developer and foam stabilizer as essential ingredients. The mixture is fed on release sheet 5 with a stirring coating gun 3 and brought into contact with skin material 4. The contact timing is set to be within the period of time, which is after cream time and before 20-50% of rise time. Next, the resultant mixture is thermally cured by heating plates 8 and 9 between conveyors 6 and 7 and finally, the release sheet 5 is peeled off. Further, when underside material is laminated, the release sheet 5 is peeled off in the midway of thermal curing treatment and the resultant mixture is brought into contact with the underside material within the period of time, which lies in 30-60% of tack-free time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a foam composite having improved cushioning properties and peel strength, which is suitable for use in furniture such as chairs and sofas and seats and interiors in vehicles.

[0002]

2. Description of the Related Art Conventionally, as a foam sheet material as described above, a cushioning property is provided between a skin material such as a woven fabric, a knitted fabric and a non-woven fabric and a backing material made of a lightweight material such as tricot half or non-woven fabric for providing surface smoothness. A material obtained by compounding a foam sheet having the above by a method such as adhesion or heat welding is widely used. When heat-sealing a foam material to a skin material, many types of cushioning materials that have become bulky by rolling a long foam sheet are handled and transported, and the expansion ratio, thickness, width, etc. differ for each application. Foam inventory,
Toxic cyanogen gas generated when fusing urethane foam to the frame has a serious effect on living things or the environment. Moreover, since the backing material is adhered after the skin material and the foam are adhered, the work process needs to be done twice. It can be mentioned as a problem.

Japanese Unexamined Patent Publication (Kokai) No. 48-58096 discloses a polyurethane-forming foam for carpet material which is directly applied to the back surface of a pre-tuffed carpet base material. In this case, a semi-rigid base material called a carpet and a polyol cross-linking base material are used. It is limited to the composite with semi-rigid foam obtained by adding MDI to the isocyanate used as, and when this method is carried out using a flexible base material, the polyurethane foam penetrates into the back surface of the base material and the base material itself. Of the flexible base material and the soft polyurethane foam raw material are mixed, the mixture permeates further into the back surface of the base material, and the composite itself is hard and the cushioning property is low. There was a problem that you could only get things that didn't work.

[0004]

SUMMARY OF THE INVENTION The present invention aims to solve the above-mentioned problems of the prior art, and in particular, has the same excellent properties as conventional products, such as cushioning property, flexibility, breathability and permeability. The purpose of the invention is to provide a method for manufacturing foam composites that has a function, improves the manufacturing environment and the stock space of raw materials, and is suitable for high-mix low-volume production.

[0005]

[Means for Solving the Problems] The present inventors have completed the present invention as a result of earnest research in order to achieve the above-mentioned object. That is, according to the present invention, a polyurethane foam-forming mixture containing a polyol, a polyisocyanate, a catalyst, a color-forming agent and a foam stabilizer as essential components is applied onto a sheet having air permeability and releasability, and then cream time is applied. This is a method for producing a foam composite, characterized in that after that, the surface of the coating layer is brought into contact with the back surface of the skin material to be laminated at a time before 20 to 50% of the rise time, and then heat-cured. In one aspect of the present invention, a breathable release sheet is peeled off after a heat curing treatment step, and in another aspect, the release sheet is peeled off in the same step and a backing material is brought into contact with the peeling surface to form a back surface. A foam composite with attached material is obtained. Here, the cream time is the time from the start of mixing the polyurethane foam-forming mixture, that is, the so-called resin solution, until the mixed solution becomes cloudy and rises in a creamy form due to the reaction, and the rise time is the mixing of the resin solution. It is the time from the start to the time when the mixed solution foams and reaches the maximum height, and the tack free time is the time from when the mixing of the resin solution is started to when the foam surface becomes tack-free. As a method to confirm the adhesiveness, use a glass rod with a smooth tip on the foam surface for 5-10
The contact shall be made for a second, and then the judgment shall be made based on the presence or absence of resistance when removing the glass rod. The polyurethane-forming mixture to be used in the present invention may be composed of well-known components as appropriate, but a mixture of a polyol, a catalyst, a foaming agent, a foam stabilizer and optionally other additives and a polyisocyanate are used in the present invention. It is preferable to mix and prepare in the step used for a method. The respective components used in the present invention are described below.

The polyol used in the method of the present invention has a terminal hydroxyl group. Polyether polyols, polyester polyols, polyether polyester polyols that are copolymers with polyester polyols, polyols such as so-called polymer polyols obtained by polymerizing acrylonitrile or styrene in the polyol, or a mixture of both, can be used. Preference is given to using polyether polyols. They have, for example, a molecular weight of 0 to 90% containing a primary hydroxyl group at the terminal, 3,000 or more and 7,000 or more.
Polyether polyols obtained by adding propylene oxide and ethylene oxide to glycerin are generally used, which are used in the production of the following general flexible polyurethane foams. Further, when elasticity is particularly required depending on the use part, it is preferable to use 5 to 50 parts by weight of the polymer polyol among 100 parts by weight of the polyol.

As the polyisocyanate used in the present invention, polyisocyanates generally used in the production of flexible urethane foam can be used. That is, TDI
(Tolylene diisocyanate) is preferable, and its isomers, that is, those having a mixing ratio of 2,4-isomer and 2,6-isomer of 80:20 or 65:35 (weight ratio) are low-priced and practical. It is preferable in terms. As tolylene diisocyanate, a purified pure product, a crude product or a mixture thereof is used. Further, if the flexibility and whiteness of the foam are required, it is preferable to use this TDI. In addition, a mixture of TDI and another polyisocyanate is used. Examples of other polyisocyanates to be mixed with TDI include pure or crude products of diphenylmethane diisocyanate or mixtures thereof, diphenyl diisocyanate, chlorophenyl-2,4-diisocyanate, P-phenylene diisocyanate, xylylene diisocyanate and polymethylene polyphenylene isocyanate. Used. Amount of polyisocyanate used based on the total amount of polyols and other compounds having active hydrogen, that is, isocyanate index (NCO index)
Is in the range of 80 to 130, but the range of 100 to 110 is particularly preferable in view of the general physical properties of the flexible polyurethane foam produced.

As the catalyst, known catalysts commonly used in this field can be used. General organometallic compounds such as dibutyltin dilaurate, tin octylate and other organotin compounds, octylzinc and other organozinc compounds, and amine compounds such as triethylamine, triethylenediamine, N-methylmorpholine and dimethylaminomethylphenol. Organic amines and the like. Further, a delayed active catalyst which exhibits catalytic ability after reaching a specific time after mixing the resin solution can also be used. These catalysts can be used alone or in combination. The amount of the catalyst used is not particularly limited and can be varied over a wide range, but is usually 0.1 to 5.0 parts, particularly 0.5 to 3.0 parts per 100 parts by weight of the polyol used in the production of polyurethane foam. preferable.

As the foaming agent, known water generally used for flexible urethane foam or a volatile liquid having a low boiling point is used. The volatile liquid having a low boiling point is, for example, trichloromonofluoromethane, dibromodifluoromethane, dichlorodifluoromethane, dichlorotetrafluoromethane, monochlorodifluoromethane, trifluoroethyl bromide, dichloromethane, etc., and these blowing agents are used alone or in a mixture. Can be used. As the foam stabilizer, a known silicone-based foam stabilizer used for foaming a polyurethane foam is preferable, and examples thereof include polydialkylsiloxane, or polysiloxane-
The silicone foam stabilizer is selected from polyalkylene oxide block copolymers, and the kind and the amount thereof are not limited as long as the object of the present invention is not impaired, but a single or combined silicone foam stabilizer mainly composed of polysiloxane-polyalkylene oxide block copolymer. Is preferably used. The amount used is in the range of 0.5 to 5.0 parts by weight, preferably 0.5 to 2.0 parts by weight, based on 100 parts by weight of the polyol.

Further, pigments known as other additives,
As the dye, a flame retardant, an antistatic agent, an organic / inorganic filler, and the like, which are compounded at the time of foaming the urethane foam, can be used as necessary.

The skin material is preferably a cloth made of a knit (tricot, double russell), a woven fabric (moquette, plain weave), a non-woven fabric or the like, but is not limited to this and may be a resin sheet. When using cloth, the material is wool,
It may be a natural fiber such as cotton, a synthetic fiber such as polyamide, polyester or polyolefin, or a mixed spinning of the both. Further, the shape of the raw material fibers is not limited. Regarding the structure of the finished cloth or sheet, it is preferable that the back surface has a dense structure as much as possible in order to prevent the permeation of the foaming liquid. Other thickness and density are not particularly limited.

As the back material, a knit (tricot, etc.),
There is no particular limitation as long as it is lightweight and provides surface lubricity such as woven fabric (plain weave), non-woven fabric, resin sheet (vinyl chloride, polyamide, polyolefin, etc.). When a cloth is used, the material thereof may be wool, natural fibers such as cotton, synthetic fibers such as polyamide, polyester, polyolefin, and a mixed spinning of both. Further, the shape of the raw material fibers is not limited. Other thickness and density are not particularly limited.

The release sheet is required to be a release sheet having gas permeability so that gas can be released during foaming so as not to impair the smoothness of the surface of the polyurethane foam.
Breathable release paper is particularly preferable. As the release paper having air permeability, for example, paper impregnated with a silicone-based release liquid is used. A resin laminated on the surface of paper or a release sheet coated with a release liquid on a resin sheet does not have air permeability, so gas accumulation during foaming tends to occur and it may disturb the smoothness of the foam surface. .

The present invention will now be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing a mode in which the release sheet is peeled off after the foaming and curing treatment step. After the resin solution is supplied by the stirring coating gun 3 onto the surface of the releasable sheet 5 from the delivery drum 2, the resin solution is contacted with the skin material 4 from the delivery drum 1 to obtain a desired foam thickness. After being heated and cured by the heat plates 8 and 9 between the conveyors 6 and 7 having a gap taking the thickness of the base material into consideration, the releasable sheet 5 is peeled off and wound on the winding drum 12 to form a polyurethane foam. The skin composite sheet 10 is wound up by a winding drum 11. FIG. 2 is a schematic cross-sectional view showing an aspect in which a backing material is attached. The conveyor 7 is divided into two, the release sheet 5 is peeled off, and the winding drum 1
It is rolled up to 0, and the backside material 11 from the delivery drum 12 is immediately contacted from below and is heat-cured by the heat plates 8 and 13 between the conveyors 6 and 14, and the composite sheet 15 made of polyurethane foam, the base material and the backside material is It is wound up by the winding drum 16.

In the present invention, the timing from the application of the polyurethane foam-forming mixture onto the release sheet to the lamination of the skin material from above is after the cream time and before 20-50% of the rise time (preferably 20-).
40%). When it is laminated before the cream time, the liquid viscosity does not reach an appropriate viscosity and it is seen that it penetrates into the skin material, and when it is laminated after 50% of the rise time, cell destruction due to compression during foam formation occurs. There are phenomena such as non-uniform foaming and decrease in elasticity.

The timing for laminating the backing material on the foam layer must be within 30-60% of the tack free time (preferably 40-50%). When laminated before 30% of the tack free time, the viscosity of the foaming liquid does not reach an appropriate viscosity, and it is difficult to peel off from the release sheet due to too high adhesiveness, and also seeps into the backing material. . If the layers are laminated after 60% of the tack free time, the adhesiveness of the foaming liquid is too low and the adhesive strength with the backing material becomes weak.

It is preferable that the surface material and / or the back surface material be subjected to permeation prevention treatment in advance. As a method for preventing the permeation of the treatment liquid into the cloth, which is preferable as the pretreatment, a treatment with a fluorine-based agent, a silicone-based agent, a paraffin-based agent or the like which is usually used as a water-repellent agent for the cloth is suitable. Furthermore, a method of preventing permeation by backing the cloth is also effective. Thus, a foam composite sheet is obtained, but the back surface of the composite sheet on which the back material is not attached can be provided with a back material separately by means such as sewing, if necessary.

[0018]

【Example】

Example 1 EXCENOL 828 (polyether polyol having a molecular weight of 5000 by adding propylene oxide and ethylene oxide to glycerin, OH value 34.1, manufactured by Asahi Glass Co., Ltd.) 80 parts EXCENOL 940 (polyol containing acrylonitrile and styrene 1: 1) Polymer polyol polymerized at a ratio of 1; OH value 26.4; manufactured by Asahi Glass Co., Ltd.) 20 parts TDI-80 (2,4-body / 2,6-body = 80/20 product, NC0% = 48.2) %, Manufactured by Sumitomo Bayer Urethane Co., Ltd. 35.8 parts SF-2962 (silicone foam stabilizer, manufactured by Toray Dow Corning Silicone Co., Ltd.) 1 part water 3 parts triethanolamine 2 parts Kaurizer No. 1 (tetramethylhexamethylenediamine, manufactured by Kao Corporation) 0.8 part Niax A-1 (mixed catalyst, manufactured by Union Carbide Co., Ltd.) 0.1 part was used as a resin solution component. It was previously confirmed by a foaming experiment that the cream time was 5 seconds, the rise time was 50 seconds, and the tack free time was 7 minutes. The apparatus shown in FIG. 1 was used. A resin solution having the above composition was rapidly stirred at 2000 rpm for 3 seconds on a breathable silicone release paper, and then applied as a layer having a thickness of substantially 1 mm, and 20 seconds after the start of mixing (40% of the rise time). ) Was previously impregnated with a 5% aqueous solution of a fluororesin SNW-15 (Asahi Glass Co., Ltd.) from above the coating layer, squeezed, pre-dried at 90 ° C for 5 minutes, and then heat-treated at 170 ° C for 1 minute. Russell knitted fabric (material PET, 2 single twisted 30 single yarns, density 40c / 20w, thickness 2mm) was laminated from the back so as to be in contact with the coating liquid, and the temperature was controlled to 70 ° C with a gap of 12mm. After the zone was run for 7 minutes to heat and cure it, the release paper was peeled off. The obtained composite was a soft and highly cushioned composite having a 10 mm thick flexible and smooth urethane foam layer on the back surface of the knitted fabric.

Example 2 Exenol 3030 (polyether polyol having a molecular weight of 3000 by adding propylene oxide to glycerin, OH value 56.0, manufactured by Asahi Glass Co., Ltd.) 100 parts Coronate 1021 (TDI-80 / polymeric MDI = 80) / 20 mixture, NC0% = 44.7%, manufactured by Nippon Polyurethane Co., Ltd.) 53.7 parts SH-194 (silicone foam stabilizer, manufactured by Toray Dow Corning Silicone Co., Ltd.) 1 part Water 4 parts Dabco-33LV (33% DPG solution of triethylenediamine, manufactured by AirProduct & Chemical Co.) 0.3 part Stanoct T-90 (tin octylate, manufactured by Furutomi Pharmaceutical Co., Ltd.) 0.3 part was used as a resin solution component. It was previously confirmed by a foaming experiment that the cream time was 9 seconds, the rise time was 78 seconds, and the tack free time was 43 minutes. The apparatus shown in FIG. 1 was used. A resin solution having the above composition was rapidly stirred at 2000 rpm for 3 seconds on a breathable silicone release paper, and then applied as a layer having a thickness of substantially 1 mm, and 16 seconds after the start of mixing (20% of the rise time). ) Was previously impregnated with a 5% aqueous solution of a fluororesin SNW-15 (Asahi Glass Co., Ltd.) from above the coating layer, squeezed, pre-dried at 90 ° C for 5 minutes, and then heat-treated at 170 ° C for 1 minute. Russell knitted fabric (material PET, 2 single twisted 30 single yarns, density 40c / 20w, thickness 2mm) was laminated from the back so as to be in contact with the coating liquid, and the temperature was controlled to 70 ° C with a gap of 12mm. After traveling in the zone for 43 minutes to heat and cure, the release paper was peeled off. The obtained composite was a soft and highly cushioned composite having a 10 mm thick flexible and smooth urethane foam layer on the back surface of the knitted fabric.

Example 3 In Example 1, the base material was a plain weave fabric (material PET, 1
000 denier, weave density 40c / 30w, thickness 1m
A composite was prepared under the same conditions as in m). The obtained composite was a soft and highly cushioned composite having a urethane foam layer having a thickness of 11 mm and having a smooth surface on the back surface of the woven fabric.

Example 4 In Example 1, the heating zone was changed to a gap of 7 mm,
A composite was prepared under other similar conditions. The obtained composite was a soft and highly cushioned composite having a urethane foam layer having a thickness of 5 mm, which was rich in flexibility and had a smooth surface on the back surface of the knitted fabric.

Comparative Example 1 In the same manner as in Example 1, the time for laminating the cloth was 4 seconds before the cream time (5 seconds after mixing) and 30 seconds after 50% of the rise time (50 seconds). A composite was prepared under the same conditions except that the same skin material as in Example 1 was used for each setting. When the laminating time was before the cream time, penetration of the foam into the base fabric was observed. At 30 seconds after 50% of the rise time (50 seconds after mixing), a foam having independent cells was obtained, but a composite having poor cushioning properties was obtained.

Comparative Example 2 Polyurethane foam sliced into 11 mm using the same base material as in Example 1 was compounded by a frame fusion (heating fusion) method. The obtained composite was a soft and highly cushioned composite having a 10 mm thick urethane foam layer on the back surface of the knitted fabric, but cyan-based gas generation was confirmed during fusion.

[0024]

[Table 1]

Example 5 The apparatus of FIG. 2 was used and operated using the same materials as in Example 1. However, the conditions after the heating zone are as follows. 1
After traveling for 3 minutes (43% of tack free time) in a heating zone whose temperature was adjusted to 70 ° C. having a gap of 3 mm to cure by heating, the release sheet was peeled off. Immediately, a tricot half (material Nylon, 30 denier, thickness 1 mm) is brought into contact with the lower surface of the foam layer as a back material,
The mixture was heated in the second heating zone for the remaining tack free time to obtain a composite which is a three-layer laminate of a soft and highly cushionable double Russell knitted fabric, a 10 mm thick urethane foam, and a tricot half. The foam had good flexibility and a smooth surface.

Example 6 A cloth which is laminated in the same manner as in Example 5 is a plain weave (material PE).
T, 1000 denier, weaving density 40c / 30w, thickness 2 mm) were used for the experiment.

Example 7 An experiment was conducted by changing the backing material laminated in the same manner as in Example 5 to a spunbonded nonwoven fabric (material Nylon, 50 g, thickness 1 mm).

Example 8 In the same manner as in Example 5, the gap was set to 8 mm in order to change the foam thickness to 5 mm.

Comparative Example 3 A urethane foam sliced to a thickness of 10 mm using the same skin material as in Example 5 was bonded by a frame fusion method, and then a tricot half was bonded to the foam surface with an adhesive. The obtained composite was soft and had a high cushioning property, but it was confirmed that cyan-based gas was generated during fusion.

[0030]

[Table 2]

[0031]

Industrial Applicability The composite obtained by the method of the present invention is a soft and highly cushioned composite having a urethane foam layer which is highly flexible and has a smooth surface. In this manufacturing method, the raw materials are in liquid form. Since it can be transported and stored in a room temperature, there is an advantage that these materials can be mixed when necessary to produce a composite composed of a base material and a flexible foam in a short time. Therefore, in the case of producing the composite, inconvenience of transportation of rolls in which a long foam sheet is rolled up and becoming bulky and handling during production, and various types of foams having different thickness, width, and expansion ratio depending on use Inventories of body sheet rolls are eliminated, and the problem of cyan gas generated in the conventional bonding process by fusion is eliminated. Further, the skin material and the back surface material can be attached in one step, which simplifies the steps.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing an apparatus used in the present invention, in which a release sheet is peeled off after a foaming treatment step.

FIG. 2 is a schematic cross-sectional view showing a mode of attaching a backing material.

[Explanation of symbols]

 1: Delivery drum (skin material) 2: Delivery drum (releasing sheet) 3: Stirring coating gun 4: Base material 5: Releasing sheet 6: Upper surface conveyor 7: Lower surface conveyor 8: Heat plate 9: Heat plate 10: Composite sheet 11: Winding drum (composite sheet) 12: Winding drum (releasing sheet) 13: Foam 14: Sending drum (lining material)

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[Procedure amendment]

[Submission date] August 10, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0014

[Correction method] Change

[Correction content]

The present invention will now be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing a mode in which the release sheet is peeled off after the foaming and curing treatment step. After the resin solution is supplied by the stirring coating gun 3 onto the surface of the releasable sheet 5 from the delivery drum 2, the resin solution is contacted with the skin material 4 from the delivery drum 1 to obtain a desired foam thickness. After being heated and cured by the heat plates 8 and 9 between the conveyors 6 and 7 having a gap taking the thickness of the base material into consideration, the releasable sheet 5 is peeled off and wound on the winding drum 12 to form a polyurethane foam. The skin composite sheet 10 is wound up by a winding drum 11. FIG. 2 is a schematic cross-sectional view showing an aspect in which a backing material is attached. The lower surface conveyor is divided into two (7 , 16) , the release sheet 5 is peeled off and wound on the winding drum 12 , and immediately the lower surface material 15 from the feeding drum 14 is contacted from below and the conveyors 6, 16
A composite sheet 10 made of polyurethane foam, a skin material and a back material is heated and hardened by the heat plates 8 and 17 between them and is wound by a winding drum 11 .

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] Explanation of code

[Correction method] Change

[Correction content]

[Explanation of Codes] 1: Delivery drum (skin material) 2: Delivery drum (releasing sheet) 3: Stirring coating gun 4: Skin material 5: Releasable sheet 6: Upper surface conveyor 7: Lower surface conveyor 8: Heat Plate 9: Heat plate 10: Composite sheet 11: Winding drum ( composite sheet) 12: Winding drum (releasing sheet) 13: Foam 14: Sending drum ( backside material) 15: Backside material 16: Bottom conveyor 17: Heat plate

[Procedure 3]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 2

[Correction method] Change

[Correction content]

[Fig. 2]

Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display area B29L 9:00 4F

Claims (5)

[Claims] 1. A polyurethane foam-forming mixture containing a polyol, a polyisocyanate, a catalyst, a color former and a foam stabilizer as essential components is coated on a sheet having air permeability and releasability, and after cream time. A method for producing a foam composite, characterized in that the surface of the coating layer is brought into contact with the back surface of the skin material for lamination at 20 to 50% or less of the rise time, followed by heat curing treatment. 2. The method according to claim 1, wherein the sheet is peeled off after the heat curing treatment step. 3. The sheet is peeled off and the backing material is brought into contact with the peeled surface during the heat curing treatment step.
The method described. 4. The contact of the backside material is tack free time 3
The method according to claim 3, wherein the method is performed within 0 to 60% of the time. 5. The method according to any one of claims 1 to 4, wherein all steps are carried out continuously while being sent.