JPS61285268A - Coating composition for suede-like surface finishing - Google Patents

Abstract

PURPOSE:To obtain a surface-finishing coating composition free of surface stickiness and capable of easily imparting slimy feeling and suede-like feeling, by compounding a specific polyurethane resin with polybutylene and silica at specific ratios. CONSTITUTION:The objective composition can be produced by compounding (A) 100pts.(wt.) of a polyurethane resin having a 100% tensile strength of 20-40kg/cm<2> in the form of a film (preferably a polymer having an average molecular weight of 1,000-3,000 and produced by reacting 1mol of a polyol component with 1-2mol of diisocyanate component and 0-1mol of chain- extender component) with (B) 5-50pts. of a polybutylene (preferably having a molecular weight of 350-1,500) and (C) 7-40pts. of silica. The obtained composition is used preferably by adjusting the solid resin content to 10-30wt%.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Application of the Invention) The present invention relates to a coating composition for finishing suede-like surfaces on artificial leather, synthetic leather, and the like.

(Prior Art) Conventionally, various coating materials have been proposed as surface finishing coating materials for artificial leather, synthetic leather, and the like. Among these methods, there is a method to give a suede feel, for example, by blending an anionic or nonionic surfactant with polyurethane resin, polyvinyl chloride resin-acrylic resin, etc. to give the coating layer a slimy feel. It has been implemented.

However, this method has drawbacks such as the oil component bleeds onto the surface of the coating layer, making it sticky when touched by hand, and leaving finger squeeze marks.

(Problems to be Solved by the Invention) An object of the present invention is to provide a surface finishing coating composition that can easily impart a slimy feel and suede feel that cannot be achieved with the conventional surface finishing coatings. It's about doing.

(Means for solving the problem) To summarize the present invention, the main component is polyurethane resin,
In a coating composition formed by blending this with polybutylene and silica, the polyurethane resin is contained in one part of the film.
00% elongation tensile strength is 20 to 40 tcg/cri,
And the blending ratio of each component is 100 parts by weight of polyurethane resin, 5 to 50 parts by weight of polybutylene, and 7 to 40 parts by weight of silica.
Parts by weight of a coating composition for finishing a smooth-grained surface.

The present invention solves the drawbacks of the conventional surface finishing coatings, and the 100% elongation tensile strength of the film is 20 to 40 KI/c, which is usually considered unsuitable for use as a surface coating.
We succeeded in solving this problem by using polyurethane resin with a low rA range and adding polybutylene and silica to it in a specific concavity.As a result, the surface is not sticky and does not have a slimy feel, just like natural suede. It was successfully granted.

The polyurethane resin used in the present invention is
It has a tensile strength at 0% elongation of 20 to 40 kg/cm. The reason for this is that for less than 20KFJ/ci,
High surface tackiness and poor blocking resistance;
This is because if it exceeds 40 KI/ctA, the ability to impart a slimy feeling will be significantly reduced.

Such a polyurethane resin varies depending on the molecular weight of the polyol component, but is generally obtained by reacting 1 to 2 moles of a diisocyanate compound and 0 to 1 mole of a chain extension component to 1 mole of the polyol component.

In addition, the 100% elongation tensile strength in the present invention is JIS
This is a value measured according to the contents described in the tensile test method of K-6301.

The components constituting the polyurethane resin used in the present invention are as shown below.

(a) Polyol component This polyol component has an average molecular weight of 500 to 4000, preferably 1000 to 300, regardless of the molecular weight distribution.
Preferably, a value in the range 0 is used. This is because if the average molecular weight is less than 500, the film will lose its flexibility and its flexibility will be poor, whereas if it exceeds 4000, it will become soft and lose its elasticity, which is undesirable.

Polyol components include polyesters, polyethers, polyester ethers, etc. having hydroxyl groups, and polyesters include polyhydric alcohols such as ethylene glycol, propylene glycol, 1,6-
Condensation products of hexanediol, trimethylolpropane, sorbitan, etc., and polyhydric carboxylic acids, such as succinic acid, adipic acid, fumaric acid, glutaric acid, isophthalic acid, pyromellitic acid, etc., and condensation products of hydroxycarboxylic acids and polyhydric alcohols. and lactone polymers.

As the polyether, for example, polypropylene glycol, polytetramethylene glycol, etc. can be used.

Further, as the polyester polyether, those obtained by adding alkylene oxide to the above polyester, those obtained by condensing polyether and polycarboxylic acid and having a hydroxyl group at the terminal, etc. can be used.

(b) Organic diisocyanate compound The organic diisocyanate compound to be reacted with the polyol component includes aliphatic diisocyanates such as hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, 2,6-lysine diisocyanate, 4
, 4'-diphenylmethane diisocyanate, 2,4-
Also usable are aromatic diisocyanates such as 2,6-dolylene diisocyanate and m-xylylene diisocyanate, and alicyclic diisocyanates such as isophorone diisocyanate and hydrogenated compounds of aromatic diisocyanates.

(C) Chain extender consisting of diol component and/or amine component The diol component used in the chain extender has a carbon number of 1
~6 diols are used. When a diol having 7 or more carbon atoms is used, blocking resistance decreases, which is not preferable.

Specifically, diols include ethylene glycol, propylene glycol, trimethylene glycol, and 1,4-
Butanediol, 1,5-bentanediol, 1,6-
Suitable examples include hexanediol, cyclopencune-1,2-diol, cyclohexane-1,2-diol, and cyclohexane-1,4-diol.

On the other hand, diamines used in combination with the above diol or used alone include aliphatic diamines such as ethylene diamine, hexamethylene diamine, trimethylhexamethylene diamine, isophorone diamine, piperazine, aminoethyl piperazine, 2,5-dimethyl piperazine,
3,9-bis-(3-aminopropyl)-2,4,8,
Alicyclic and heterocyclic diamines such as 10-tetraxaspiro[5,5]undecane, Zara, m-phenylenediamine, p-phenylenediamine, 2,4-tolylenediamine, m-xylylenediamine, p -Aromatic diamines such as xylylene diamine and 4,4-diaminodiphenylmethane are used.

Solvents used in producing polyurethane resins from the three components (a) to (C) include dimethylformamide, diethylformamide, dimethylacetamide, acetone, methyl ethyl ketone, dimethyl sulfoxide, etc. Any combination of these agents may be selected from those used as resin solubilizers.

The number average molecular weight of the polyurethane resin is adjusted by the number average molecular weight of the polyol component and the molar amount of the chain extender used in polyurethane production.

An example of the polyurethane resin used in the present invention is that 1 mol to 2 mol of a diisocyanate component is added to 1 mol of polyester polyol or polyether polyol having a molecular weight of 500 to 4000 at 50 to 100'C.
The resulting urethane prepolymer having terminal isocyanate groups was diluted with an organic solvent and further reacted for 2 to 12 hours at 40 to 100°C using 0 to 1 mol of a chain extender.
Obtained by reacting for 50 hours.

Polybutylene preferably has a molecular ff of 1350 to 1500, and is added in an amount of 5 to 50 parts by weight per 100 parts by weight of the polyurethane resin. This is an essential component for imparting a slimy feel to the surface of the base material, and if the amount is less than 5 parts by weight, the effect cannot be obtained;
If it exceeds 0 parts by weight, tackiness will increase, which is undesirable.

Silica is an essential component for suppressing surface tackiness, and also has the effect of imparting a sweaty appearance and feel.

In the present invention, silica is added in an amount of 7 to 40 parts by weight per 100 parts by weight of the polyurethane resin. This is because if the amount added is less than 7 parts by weight, the tackiness suppressing effect and the sweaty appearance cannot be improved, whereas if it exceeds 40 parts by weight, the slimy feeling becomes undesirable.

The coating composition of the present invention is used after adjusting the resin solid content to 10 to 30% by weight.

Materials to which the coating composition of the present invention can be applied include woven fabric,
Examples include nonwoven fabrics, synthetic leather, artificial leather, paper, wallpaper, synthetic resin sheets, and the like.

As a coating method, a spray method, a gravure printer method, a roll coater method, a reverse coater method, a doctor knife method, a coating, etc. can be used.

(Example) In order to explain the present invention more specifically, Examples will be shown below. However, the present invention is not limited to the scope of these examples. All parts in the examples are by weight unless otherwise specified.

[Preparation of polyurethane resin solution A] 100 parts of polyester having an average molecular weight of 2,000, 4.4
16.25 parts of '-diphenylmethane diisocyanate was added, and the reaction was carried out at 70 to 80'C for 4 hours. Next, 81.3 parts of dimethylformamide and 190.265 parts of methyl ethyl ketone were added, followed by 0.135 parts of 1,4-butanediol, and the reaction was carried out at 60 to 80'C for 4 hours to prepare a polyurethane resin solution. The tensile strength at 100% elongation of this polyurethane resin film was measured and found to be 20'j/cri.

Preparation of Polyurethane Resin Solution In the preparation of copolyurethane resin solution 1, a polyurethane resin solution was prepared by the same method except for changing the contents shown in Table 1.

Experimental Example 1 4333 parts by weight of a polyurethane resin solution was added with polybutylene (trade name: Polybutene 5, manufactured by Idemitsu Petrochemical Co., Ltd., with a molecular weight of 4.
00) 15 parts by weight and fine silica powder (product name TS-1
After thoroughly mixing, 1/1 of methyl ethyl ketone/dimethyl formamide was added as a mixed solvent to adjust the resin solid content to 15% by weight, and a surface finishing coating composition was prepared. I got it.

Examples 2 to 5 and Comparative Examples 1 to 2 Surface finishing coating compositions were prepared in the same manner as in Example 1, except that the type of polyurethane resin solution used was changed as shown in Table 2. did.

Table 2 Examples 6-7 and Comparative Examples 3-4 Surface finishing coating compositions were prepared in the same manner as in Example 1 except that the polybutylene was changed to one having the molecular weight shown in Table 3.

Examples 8 to 9 and Comparative Examples 5 to 7 In the method of Example 1, the amount of polybutylene added was
The surface finish coating compositions were prepared in the same manner with all the variations shown in the table.

Table 4 Examples 10 to 11 and Comparative Examples 8 to 10 In the method of Example 1, the amount of silica fine powder added was
The surface finishing coating compositions were prepared in the same manner with all the variations shown in the table.

Table 5 Experimental Examples Using each of the coating compositions prepared in Examples 1 to 11 and Comparative Examples 1 to 10, the surface of urethane synthetic leather was coated with a gravure printer (100 meshes) and then heated to 80°C.
The surface was finished by drying for 1 minute. The coating was 2-3μ.

The condition of the obtained coating film was as shown in Table 6.

Claims (1)

[Claims] 1. In a coating composition comprising a polyurethane resin as a main component and blended with polybutylene and silica, the polyurethane resin has a 100% elongation tensile strength of 20 to 40 kg/cm^2, and each A coating composition for finishing a suede-like surface, characterized in that the blending ratio of the components is 5 to 50 parts by weight of polybutylene and 7 to 40 parts by weight of silica to 100 parts by weight of polyurethane resin.