JPH04175392A - Method for bonding seat - Google Patents

Abstract

PURPOSE:To make it possible to perform bonding which does not spoil the band of a seat material after reaction curing by using a hot-melt adhesive consisting of a specified blocked isocyanate group-contg. urethane prepolymer. CONSTITUTION:After a cushioning base material is spray-coated with a hot-melt adhesive consisting of a blocked isocyanate group-contg. urethane prepolymer with a block structure of formula A-B-A or A-(BA)n-A (wherein n is 1-10) prepd. by bonding (A) a polyethylene oxide block or a polyalkylene oxide block terminated with the above block and (B) a polyester block with a glass transition point of 0-100 deg.C through an excess amt. of a diisocyanate compd., a skin material is laminated thereon and hot pressing is performed for bonding. It is possible thereby to perform bonding providing properties (e.g. low modulus) which do not spoil the hand of a seat material (e.g. urethane foam) after reaction curing.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for adhering seating sheets, and more specifically, to adhesive processing of seating sheets by using a moisture-curable hot-melt adhesive having initial cohesive strength and low monocularity. The present invention relates to an adhesive processing method for seat sheets that maintains the texture of the sheet material and can achieve rapid curing, especially by using steam in combination with hot pressing.

Topics to be solved by conventional technology and inventions Due to the demand for higher quality and high design quality for automobile interior materials, a processing method with excellent design that adheres the skin material to the cushion base material has been developed, even for seat seats. It is widespread. Currently, solvent-based urethane adhesives are used in this adhesive processing method, but
There are problems with environmental health and safety, and for this reason there is a growing demand for solvent-free products.

Means for Solving the Problems In order to meet such demands, the present inventors conducted intensive studies and found that a polyethylene oxide block or a polyalkylene oxide block containing a polyethylene oxide block end and a glass transition point (Tg) were obtained through diisocyanate compounds. A block-type isocyanate group-containing urethane prepolymer having a structure in which polyester blocks with a high degree of oxidation are arranged in a specific manner produces initial cohesive force sensitively to temperature drops and is highly reactive to moisture. The inventors have discovered that even when used as a hot-melt adhesive, it has physical properties (low modulus) that do not impair the feel of seat material (e.g. urethane foam) after reaction curing, leading to the completion of the present invention.

That is, the present invention provides a polyethylene oxide block or a polyalkylene oxide block (A) having a polyethylene oxide block at the end, and
Polyester blocks (B) at 0°C are bonded via an excess amount of diisocyanate compound to form a block-type isoneanate having a block structure represented by the formula % formula %) [wherein n is 1 to 10] group-containing urethane prepolymer (hereinafter referred to as block NGO)
A moisture-curing hot-melt adhesive characterized by comprising a prepolymer (referred to as a prepolymer), and a method for processing a seat sheet comprising adhering a skin material to a cushion base material, the moisture-curing hot-melt adhesive described above The present invention provides an adhesive processing method for a seat notebook, which is characterized in that after spray-coating the cushioning material on a cushion base material, the skin material is superimposed and hot-pressed to adhere.

The above-mentioned block NGO prepolymer in the present invention is, for example, polyethylene glycol or a block type polyoxine ethylene-alkylene polyol having a polyethylene oxide block at the end (hereinafter referred to as block polyol) and an excess amount of a diisocyanate compound. The ratio is greater than 1 (preferably from 1.0 to
3.0) (usually 1 at 50 to 100°C)
~24 hours) to obtain a urethane prepolymer containing terminal isocyanate groups, and a polyester polyol having a TgO of ~100°C (preferably 5 to 50°C) is added to the terminal N-terminated urethane prepolymer.
COlo H increases by 1 (preferably 1.0 to 3°0)
It can be produced by reacting (usually at 50 to 120°C for 1 to 24 hours) so that

In addition, in the formula showing the above block structure, the polyethylene oxide block in A contributes to low modulus, and the polyester block in B contributes to the expression of initial cohesive force.

The above-mentioned block polyol refers to a low molecular weight active hydrogen compound having two or more active hydrogen atoms (for example, ethylene glycol, propylene glycol, butylene glycol, 1.
Diols such as 6-hexanediol, glycerin,
Alkylene oxide (propylene oxide, Butylene oxide, etc.) and ethylene oxide are combined into block copolymers obtained by ring-opening polymerization. molecule! 200-200
0 is used.

Examples of the diisocyanate compound include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 2°4.4- or 2,2.4-
Trimethylhexamethylene diisocyanate, dodecamethylene diisocyanate, 1.3-cyclopentane diisocyanate, 1.4-cyclohexane diisonanate, 1.3-cyclohexane diisonanate, 4.4
°-methylenebis(cyclohexylisonanate),
Methyl 2.4-cyclohexane neusonanate, methyl 2.6-cyclohexane diisocyanate, 1.4-
Bis(isocyanatomethyl)noclohexane, 1.3
-bis(isocyanatomethyl)cyclohexane, m-
Phenylene diisonoanate, p-phenylene diisonoanate, 4,4'-diphenyl diisonoanate, 1
．． 5-naphthalene diisonanate, 4,4°-diphenylmethane diisocyanate, crude diphenylmethane diisonanate, 2,4- or 2,6-dolylene diisonanate, 4,4°-toluidine noisocyanate, cyanidine diisocyanate, 4 .4°-diphenyl ether diisocyanate, 1.3- or 1.4
-xylylene diisocyanate, ω, ω゛-diisocyanate 1,4-diethylbenzene, etc., and one or more of these may be used. Particularly preferred in the present invention are 4,4°-diphenylmethane diisocyanate (MDI) and tolylene diisonanate.

The above polyester polyol refers to polybasic acids (e.g. phthalic acid, adipic acid, terephthalic acid, isophthalic acid,
sebacic acid, dimerized sulfuric acid, maleic acid, and their di-lower alkyl esters) and polyhydroxo compounds (such as the above-mentioned diols and triols, as well as diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol) The hydroxyl-terminated polyester obtained by reacting the hydroxyl group-terminated polyester (such as A material having a Tg of 0 to 100°C and a molecular weight of 500 to 30,000 is used.

The moisture-curable quick-melt adhesive according to the present invention is composed of the block NGO prepolymer described above, and further includes a tackifier resin (rosin resin, rosin ester resin, hydrogenated rosin ester resin, terpene resin, terpene resin, etc.) as necessary. (phenol resin, hydrogenated terpene resin, petroleum resin, etc.),
Fillers (silicic acid derivatives, talc, metal powder, calcium carbonate, clay, carbon black, etc.), plasticizers (dibutyl phthalate, dioctyl phthalate, dicyclohexyl phthalate, diisooctyl phthalate, dioctyl phthalate, dioctyl phthalate, butyl benzyl phthalate) , trioctyl phosphate, epoxy plasticizer, toluene-sulfamide, chloroparaffin, ampic acid ester, castor oil, etc.), thixotropic agents (bentone,
Appropriate amounts of silicic anhydride, silicic acid derivatives, urea derivatives, etc.), dyes and pigments, curing catalysts, ultraviolet absorbers, flame retardants, nolan compounds, dehydrating agents, etc. may be blended.

In order to perform the adhesive processing for seat sorting using the adhesive of the present invention, the following steps may be performed.

First, 10% of the adhesive of the present invention was applied to the surface of a cushion base material (for example, urethane foam, fabric, urethane foam with stockinette, etc.), which is one of the seat sheet materials.
After melting at 0-120℃, usually 30-100g
/a+', then the other skin material (e.g. urethane foam, fabric, stockinated urethane foam, etc.) is overlaid, usually 5
Hot pressing is performed under conditions of 0 to 100°C. In this case, since both the cushion base material and the skin material of the seat material have excellent heat insulation properties, by using steam together during hot pressing, curing can be accelerated by supplying moisture and heat. In this way, after hot pressing (and using steam together), moisture curing is performed by curing at room temperature and humidity, thereby making it possible to obtain a seat sheet with a low modulus and a good texture.

Next, the present invention will be explained in more detail with reference to Examples and Comparative Examples.

Example 1 MDI of 609 was added to 100 g of polyethylene oxide (manufactured by Asahi Glass Co., Ltd., Efsenol 550) (NCo10
After reacting at 80°C for 5 hours to obtain a urethane prepolymer containing terminal isocyanate groups, polyester polyol (manufactured by Nippon Gosei Kagaku Kogyo Co., Ltd., Polyester-LP-035, T820°C) 9309 was added. (terminal NCO10H=2.3) and further reacted at 120° C. for 4 hours to obtain a block NCO prepolymer.

Example 2 Polyethylene glycol (manufactured by Sanyo Chemical Industries, Ltd., pE
G400) Add MDI of 1459 to I O09 (NC
o10H=2.3), reacted at 80°C for 5 hours to obtain a urethane prepolymer containing a terminal isone anate group, and then added polyester polyol (manufactured by Nippon Gosei Kagaku Kogyo Co., Ltd., Polyester-LP-033, Tg 15°C) 22509. (terminal NGO10H = 2°3), and further heated at 120°C for 4
A block NCO prepolymer is obtained by reacting for a period of time.

Comparative Example 1 MDI of 3.759 was added to the polyester polyol (Polyester-t, P-035) I 009 used in Example 1 (NGO10H = 2.4) and reacted at 120°C for 4 hours to obtain terminal isocyanate group-containing Obtain a urethane prepolymer.

Dumbbell physical property test The target prepolymers obtained in Example 1.2 and Comparative Example 1 were made into a sheet with a thickness of 0.8 + n + 11, and heated at 20°C for 6
After curing for 168 hours at 5% RH, 50% modulus,
The degree of elongation and breaking strength were measured. The results are shown in Table 1 below.

Example 3 and Comparative Example 2 (Adhesive Processing Method) The target prepolymers of Examples 1 and 2 and Comparative Example 1 were respectively heated and melted at 120°C, and these were mixed into polyurethane foam (300X
300x30m) at a rate of 50g/m'. Next, a fabric (300 x 300 x 4 mm) is superimposed on the polyurethane foam coated surface and pressed using a press molding machine consisting of an upper plate and a lower plate. At the same time, the lower plate is heated to Blow in vacuum steam for 1 minute.

Thereafter, it was subjected to moisture curing by curing at 20° C. and 65% RH for 24 hours, and the following heat resistance creep test was conducted. The results are shown in Table 1 below.

Heat resistance creep test 300g load in 80℃ atmosphere, 180℃ after 24 hours
Measure the peeling length (+++a+).

In addition, instead of the steam press used in the above-mentioned pressing, the results were also shown when pressing was performed for 1 minute using an 80° C. hot press that does not allow steam to pass through.

Claims (1)

[Claims] 1. A polyethylene oxide block or a polyalkylene oxide block (A) having a polyethylene oxide block at the end and a polyester block (B) having a glass transition point of 0 to 100°C are combined via an excessive amount of a diisocyanate compound. consisting of a block-type isocyanate group-containing urethane prepolymer having a block structure shown by the formula: A-B-A or A-(BA)n-A [where n is 1 to 10] A moisture-curing hot melt adhesive. 2. In a method for manufacturing a seat comprising a skin material adhered to a cushion base material, the hot melt adhesive according to claim 1 is spray applied to the cushion base material, and then the skin materials are superimposed and hot pressed. An adhesive processing method for a seat sheet, which is characterized by adhering the seat sheet by performing the following steps. 3. The adhesive processing method according to claim 2, wherein steam is used in conjunction with hot pressing to accelerate heating and curing.