JPS5921991B2 - Dyeing method with good dye fastness for artificial leather - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dyeing method for providing artificial leather with excellent waxability in the dyeing room.

Conventionally, various artificial leathers have been proposed in which binder polymers such as polyurethane and acrylic resin are contained in fibrous entangled bodies such as nonwoven fabrics using polyester fibers.In particular, artificial leathers made of polyurethane with elastic properties have been proposed. It is well known that it has excellent flexibility and a favorable wrinkle formation pattern.

However, when dyeing artificial leather, since the constituent fibers of the artificial leather are polyethylene terephthalate fibers,
The actual situation is that disperse dyes commonly used for these fibers are used.

When dyed artificial leather is dyed with disperse dyes, the dye comes off during washing or dry cleaning, causing the color to fade or staining other items to be washed.

Also, when dyed artificial leather is exposed to sunlight for a long period of time,
It has the disadvantage that it may fade in color and has poor wax fastness over time.

The polyurethane constituting the artificial leather is extremely dyeable with disperse dyes compared to polyester fibers.

Therefore, in the case of dyeing with a disperse dye, the disperse dye is naturally distributed and dyed competitively between these two components, and as a result, a large amount of the disperse dye is dyed on the polyurethane blade.

However, it is well known that disperse dyes generally have a weak affinity for polyurethane, which causes a decrease in color fastness as described above.

This deterioration in color fastness is particularly noticeable in suede-like artificial leathers, especially in suede-like artificial leathers made of entangled polyester fibers of ultra-fine fineness that have recently been commercially available.

In other words, in the case of artificial leather made of ultra-fine fiber entanglement and a polyurethane polymer binder, the fibers are thin, so when dyeing a deep color, a higher concentration of dye is used than when dyeing ordinary fabric. Requires.

For this reason, the amount of distributed dyeing applied to polyurethane becomes even greater, and as a result, the dye fastness becomes worse.

The present inventors have conducted extensive research to improve these drawbacks, and as a result, have arrived at the present invention.

That is, the present invention provides a fiber entangled body made of polyester fibers,
When dyeing artificial leather composed of a binder made of a polyurethane polymer, the artificial leather dyed with a disperse dye is treated with an organic solvent that dissolves the disperse dye, and then dyed with an l:2 type complex salt dye. It is a dyeing method with excellent dyeing room wax properties.

The organic solvent used in the method of the present invention is an organic solvent having a solubility of the disperse dye at room temperature of 5 g/1 or more.

Preferably, the substance has a boiling point of about 150°C or less.

For example, perchlorene, trichlene, trichloroethane,
Examples include benzene, acetone, dioxane, methyl cellosolve, and the like.

Furthermore, it is also possible to mix and use any combination of these substances.

The organic solvent used in the method of the present invention preferably has an affinity for disperse dyes and has an appropriate swelling ability for polyurethane without degrading it.

Furthermore, it is preferable to use a material that does not deteriorate polyester.

Conventionally, the method for decolorizing artificial leather dyed with disperse dyes is as follows:
Decolorization was performed by treatment in water or hot water using a chemical reducing agent alone or in combination with an alkaline compound.

However, the problem with this method is that the polyurethane deteriorates, and the color-changing dyes desorbed by alkali reduction decomposition recontaminate the polyurethane, causing the hues of the fibers to appear separated in the artificial leather as a whole, lowering its commercial value. .

In the method of the present invention, the artificial leather dyed with disperse dyes is treated with an organic solvent to physically decolorize the disperse dyes attached to the polyurethane, thereby eliminating the conventional drawbacks and greatly improving the method.

The artificial leather obtained in this way is then dyed with l:2 type complex salt dye and further soaped, so that the polyester fiber and polyurethane are dyed to the same depth of hue, and the artificial leather as a whole is dyed. It has a deep hue, has excellent color fastness, and the dye does not come off during washing or dry cleaning, so the color does not fade or stain other items to be washed.

The polyester constituting the artificial leather applied to the present invention refers to an aromatic polyester, which includes one or more acid components whose main components are aromatic dicarboxylic acids or lower alkyl esters thereof and one glycol. Or it is a polyester synthesized from two or more types.

Aromatic dicarboxylic acids are terephthalic acid, naphthalene-2
, 6-dicarboxylic acid, diphenyldicarboxylic acid, diphenyl etherdicarboxylic acid, ethylene-1,2-bis(
P-carboxyphenoxide) and P,P'-disulfonylbenzoic acid.

Glycols include polymethylene glycol having 2 to 10 carbon atoms, cyclohexane dimetatool, p-xylylene diol, benzene-1,4-bis(β-oxyethoxide), and the like.

In addition to the basic polyester components, isophthalic acid, phthalic acid, oxalic acid, adipic acid, cepatic acid, 6,
6'-disulfonylcaproic acid, triethyl alcohol, triethyl alcohol, polyethylene glycol,
It is also possible to add a small amount of neopentyl glycol, bisphenol-A1 pentaerythritol, etc. for copolymerization.

The fibers that are the constituent components of the artificial leather are produced by spinning them using a known melt spinning method.

That is, polyester is spun alone.

Polyester and other polymers are combined and spun into a multicomponent fiber with polyester as an island component (or core component or fine fiber component) and other polymers as a sea component (or sheath component).

For example, three polymers are spun, such as the above-mentioned aromatic polyester as an island component and polyethylene or polystyrene as a sea component, so as to be substantially continuous in the direction of the fiber axis.

For example, Special Publication No. 39-29636, Special Publication No. 44-183
A multicore-sheath type composite spinning method represented by No. 69, a spinning method in which three polymers are discharged from separate gear pumps, and a sea-island structure fiber is obtained by performing multilayering, joining, and division operations; A special mixed spinning method to obtain a sea-island structure fiber through a static mixer, and a so-called chip blend mixed spinning method in which the three polymers are aged in the form of chips and then spun, etc. can be adopted.

Examples of the method for producing the fiber entangled body include a method in which a fibrous nonwoven web is prepared by a known dry method or wet method, and the fibrous nonwoven web is punched by needle punching, air jet, or water jet.

Preferably, the entangled body is formed by needle punching.

Furthermore, the fiber may be a fabric obtained by knitting, weaving, etc., or a raised fabric thereof.

The polyurethane constituting the artificial leather applied to the present invention is a main chain formed by urethane bonds produced by reacting one or more diisocyanate components, one or more polymer diol components, and a chain extender. refers to a polymer composed of

Examples of the diisocyanate include tolylene diisocyanate, diphenylmethane diisocyanate, phenylene diisocyanate, naphthalene diisocyanate, biphenyl diisocyanate, hexane diisocyanate, and cyclohexane diisocyanate.

Polyester diol components include polyester diols formed from dicarboxylic acids and dihydric alcohols, such as polyester diols from adipic acid and ethylene glycol, polyester diols from adipic acid and butylene glycol, and polyester diols from adipic acid, ethylene glycol, and propylene glycol. Examples include polyester diols such as polyester diol, polyalkylene ether glycols such as polycaprolactone glycol, polyethylene ether glycol, polypropylene ether glycol, and polyifthylene ether glycol.

Chain extenders include compounds having two active hydrogen atoms, such as diamines such as aliphatic diamines, aromatic diamines, and alicyclic diamines, and glycols such as ethylene glycol, propylene glycol, and butylene glycol. One or more chain extenders are selected and reacted.

The obtained polyurethane can be used alone or in any combination of polyurethanes with different components to form a polymer blend.

Artificial leather can be manufactured by using the above-mentioned polyester fibers and polyurethane and applying a known method. For example, a nonwoven fabric of the above-mentioned polyester fibers is immersed in a polyurethane solution or a polyurethane emulsion, and then the polyurethane is wet-coagulated or dry-coagulated. The polyurethane is coagulated as a microporous elastic body and used as a binder for the fiber entangled body.

A more preferred embodiment of the present invention is suede-like artificial leather using ultrafine fibers, and this artificial leather is produced, for example, by the following method.

A polyurethane emulsion is impregnated into the entangled body of multicomponent fibers obtained by the above-described spinning method of the polyester component and other polymer components, and this is introduced into a suitable coagulation bath to wet-coagulate or dry-coagulate the polyurethane. Then, the fibers are treated in a solvent such as a sea-component solvent to dissolve and remove the sea-component polymer of the multi-component fibers, resulting in a fiber entanglement consisting of ultra-fine polyester fibers (preferably having an average fineness of 0.1 denier or less).

After removing the extraction solvent contained in the obtained sheet material and drying it, the surface is puffed to obtain artificial leather having a raised fiber layer.

In the case of the artificial leather made of the fiber bundle entangled body with ultrafine fineness obtained in this way, the improvement is particularly large, and the above-mentioned drawbacks are solved.

That is, in the case of dyeing by the method of the present invention, there is no disperse dye in the polyurethane constituting the artificial leather, and as a result, there is no disperse dye present in the polyurethane constituting the artificial leather, which is different from that seen in conventional disperse dye dyed products of artificial leather made of polyester fiber entanglement and polyurethane. It does not have such poor washing fastness.

In addition, the l:2 type complex salt dyes used in the present invention are S, D
-C and refers to dyes that belong to the color index co-edited by A, A, T, C, C as acidic dyes, and whose chemical structure is a 1:2 metal complex.

Further, dyeing with the dye and disperse dye can be carried out by a conventional method.

EXAMPLES The present invention will be specifically explained below with reference to Examples, but the present invention is not limited thereto.

In the examples, all parts indicating the amount added indicate parts by weight, and the intrinsic viscosity [η] of phenol and tetrachloroethane is 50:
This value was measured at 30°C in a solvent mixed at a weight ratio of 50%.

Example l 250 parts of dimethyl terephthalate, 240 parts of ethylene glycol, and 0.05 part of zinc acetate were charged into a reaction vessel.
After heating to 0°C and stirring, the transesterification reaction was carried out for 2 hours while removing by-product methanol, and then 0.06 part of trimethyl phosphate and 0.10 part of antimony oxide were charged, and the temperature was gradually increased and the pressure was reduced to 280°C. 0.2-0.5
The reaction was carried out at mmHg for 2 hours.

The obtained polymer was supplied to a pelletizer from a spinneret installed at the bottom of the reactor, and taken out as chips.

This polyester is a white polyester chip with an intrinsic viscosity of 0.72.

This chip was used as an island component, while polyethylene (M, 1.~
30) was melt-spun using a sea component at an island/sea component ratio of 50150 using a multi-filament composite spinning method, stretched approximately 4.5 times in a hot water bath to produce a fiber with a single fiber fineness of 6 dr, and mechanically crimped. After processing, the staples cut to 50 mm length were made into a random web using a card method using a standard method, and 70 mm per square centimeter was created at a depth of 11 mm using a No. 40 regular needle.
Needle punched under zero conditions, weight 1000g
A three-dimensional laminated nonwoven sheet with a thickness of /m was produced.

Next, the nonwoven sheet is heat-treated under hot air at 115°C to make it heat-set and densified, and the apparent density is about 0.30 g/Cr! , After binding, polyester polyurethane (average molecular weight 20
00 polyethylene propylene adipate glycol,
4. Completely impregnate a 13% dimethylformamide (hereinafter referred to as DMF) solution of a polyurethane (polyurethane whose inocyanate group has a nitrogen atomic weight of approximately 4%) obtained by reacting 4'-diphenylmethane diisocyanate and ethylene glycol, and then DMF.
Wet coagulation in a 40% aqueous solution.

The obtained sheet was extracted and removed with hot toluene to remove the sea component of polyethylene in the fibers, and after removing the toluene, it was sliced into two parts, and both sides were puffed with 120 mesh side paper, so that the thickness of the napped layer on both sides was 0. A raw artificial leather fabric of .8 mm was obtained.

This artificial leather was dyed with a disperse dye using the bath composition shown below at a bath ratio of 50:1, a bath temperature of 110°C, and a time of 90 minutes.
The treatment was repeated twice at room temperature for 2 minutes at a bath ratio of 50:1 at g/l.

Dye Dianix Red TB-8E (C, I-
Disperse Red 181) (manufactured by Mitsubishi Chemical Industries, Ltd.) Dye concentration 10% owf Dinure-TL l g/l (anionic surfactant, manufactured by Kaisei Kagaku Kogyo Co., Ltd.) This treated artificial leather was treated with the bath composition shown below. Bath ratio 50
:1: Dyeing with a 1=2 type complex salt dye was carried out at a bath temperature of 90° for 160 minutes.

Dye Irgalan Red 2BL (C, l-A
c1d &d 219) Dye concentration 3%owf.

Then, soaping was carried out for 30 minutes at a bath temperature of 60°C with a bath composition of ammonium bisulfate 3% owf and monogen xi/l and sodium carbonate 1g/l,
The dyed product obtained by thorough washing with water and drying had an S value (Kuber's force, calculated from Munk's formula) of 15.0, indicating excellent color development.

When its washing fastness was measured according to JIS-LO844, No. A-2, it was 4th to 5th grade for discoloration and fading, 4th to 5th grade for staining (attached white cloth, cotton), and 4th grade (attached white cloth, nylon). It showed excellent firmness.

Further, the light fastness was measured according to JIS-LO843 and was found to be grade 4.

Comparative Example 1 The artificial leather used in Example 1 was dyed with a disperse dye using the bath composition shown below at a bath ratio of 50:1, a bath temperature of 110°C, and a time of 90 minutes, and then dyed with 1 g of hydrosulfide.
/! l, caustic soda 19/11 amylazine (nonionic surfactant, manufactured by Daiichi Kogyo Seiyaku ■) 1g/11 bath ratio 50:
The dyed product obtained by performing reduction washing at a bath temperature of 80° C. for 30 minutes, thoroughly washing with water, and drying had a N/S value (Kuber's force, calculated from Munk's equation) of 10.2.

Dye Dianix &d TB-8E (C-IDi
sparse Red 181) (manufactured by Sankasei Industries ■) Dye concentration 10% owf Disper TL 1. ! 9/It When the washing fastness and light fastness were measured in the same manner as in Example 1, the washing resistance was 3rd grade for discoloration and fading, and 1st grade for staining (
Attached white cloth, cotton), Grade 1 (attached white cloth, nylon),
In addition, the light resistance was extremely poor at grade 1.

Example 2 227 parts of dimethyl terephthalate, 23 parts of dimethyl isophthalate, 240 parts of ethylene glycol, 0 parts of zinc acetate
．． 0.05 parts of trimethyl phosphate was charged into a reaction vessel, heated to 180°C with stirring, and transesterified for 2 hours while removing by-product methanol. After charging, the temperature was gradually raised and the pressure was reduced, and the reaction was carried out at 280° C. and 0.2 to 0.5 mmHg for 2 hours.

The obtained polymer was supplied to a pelletizer from a spinneret installed at the bottom of the reactor, and taken out as chips.

This polyester is a white polyester chip 0 with an intrinsic viscosity of 0.75.

This chip 0 was used as an island component and polyethylene as a sea component, and was spun using a special mixing spinneret so that the island/sea component ratio was 50150, and a 6 dr fiber was produced by a water bath drawing method.
After mechanical crimping, it was cut into a length of 50 mm to obtain a stable.

After creating a random web using this stable 4
A three-dimensional entangled nonwoven sheet with a weight of 1000 g/m'' was produced by needle punching using a No. 0 regular needle at a depth of 111 m and 700 times per square centimeter.

The sheet was then heat-treated under hot air at 115°C to heat-set and densify it to an apparent density of about 0.30 g/i, and then polyether-based polyurethane (polytetramethylene ether glycol (90) with an average molecular weight of 2000) 13% of polyurethane obtained by reacting polyethylene ether glycol (io), 4,4'-diphenylmethane diisocyanate and 4,4'-diphenylmethane diamine)
The above nonwoven fabric sheet was impregnated with DMF solution, and DMF40
% aqueous solution.

Next, after extracting and removing the sea components in the fibers, the fibers were sliced into two and puffed on both sides with 120-mesh side paper to obtain an artificial leather raw fabric with a thickness of 0.2 mm and a nap layer formed thereon.

This artificial leather was washed with the bath composition shown below at a bath ratio of 50:1.

After dyeing with a disperse dye at a bath temperature of 105°C for 90 minutes, the dyeing was repeated twice at a bath ratio of 50:1 at room temperature for 10 minutes with Perculen (solubility of the following disperse dye at room temperature: 5 g/13). .

Dye Dian ix Brown GS-E(C
,I.

N, O unknown) (manufactured by Mitsubishi Chemical Corporation) Dye concentration lO%owf Disper TL 1f! /13 This treated artificial leather was heated to a bath ratio of 50 with the bath composition shown below.
:1. Dyeing with a complex salt dye was carried out at a bath temperature of 90° C. for 60 minutes.

Dye Vidlon Fast Brown R dye concentration 2% owf Ammonium sulfate 3% owf then monogen 1g/l and sodium carbonate 19/13
The washing fastness of the dyed artificial leather obtained by soaping for 30 minutes at a bath temperature of 60°C with a bath composition of Fading grade 5, staining grade 5 (attached white cloth, cotton), 4-5
grade (attached white cloth, nylon) and showed excellent firmness.

Comparative Example 2 The artificial leather used in Example 2 was dyed with a disperse dye using the bath composition shown below at a bath ratio of 50:1, a bath temperature of 110°C, and a time of 90 minutes, and then dyed with hydrosulfide 1.
g/L caustic soda 1g/11 amylazine 1g/11. The washing fastness of the dyed artificial leather obtained by performing reduction washing at a bath ratio of 50:1 and a bath temperature of 80°C for 30 minutes, thoroughly rinsing with water, and drying was measured in the same manner as in Example 2. Then,
Discoloration and fading were grade 3, staining was grade 2 to 3 (attached white cloth, cotton), and staining was grade 2 (attached white cloth, nylon), and it was poor.

r dye Dianix Brown GS-E
1 (C, 1, NO unknown) (manufactured by Mitsubishi Chemical Corporation) Dye concentration 10% o w f Deinushi-TL 1 g/l Example 3 Three-dimensionally laminated nonwoven sheet used in Example 1 and Example 2 An artificial leather original fabric was obtained by the conventional method of Example 1 using the polyurethane used in Example 1.

This artificial leather was dyed with a disperse dye using the bath composition shown below at a bath ratio of 50:1 and a bath temperature of 110°C for 90 minutes.
0150, solubility of the following disperse dye at room temperature 6g/13)
The bath ratio was 50:1. The treatment was repeated twice at room temperature for 2 minutes.

Dye &sol ine Blue FBL(C,1
, Disperse Blue 56) Dye concentration 10% off Di 5per TL 1,! 9/13 This treated artificial leather was washed with the following bath composition at a bath ratio of 50:
1. Dyeing with type 2 complex salt dye was carried out at a bath temperature of 90° C. for 60 minutes.

Dye Irgalan Blue GL (C-I-A
cid Blue 166) Dye concentration 3% owf Ammonium sulfate 3% owf Then monogen xg/13 and sodium carbonate lfl/
1 bath composition with a bath ratio of 50:1. The washing fastness of the dyed product obtained by soaping at a bath temperature of 60° C. for 30 minutes, washing thoroughly with water, and drying was as shown in Example 1.

When measured using the same method, it was grade 5 for discoloration and fading, and grade 4 to 5 for staining (
It was grade 4 to 5 (attached white cloth, cotton) and 4 to 5 grade (attached white cloth, nylon), and showed excellent fastness.

Furthermore, when the light resistance was measured by the same method as in Example 1, the light fastness waxiness was excellent at grade 5 to 6.

Comparative Example 3 The artificial leather used in Example 3 was dyed with a disperse dye using the bath composition shown below at a bath ratio of 50:1, a bath temperature of 110° C., and a time of 90 minutes.

Dye Re5oline Blue FBL (C,1
, Disperse Blue 56) Dye concentration 101% o w f Di 5per TL 1 g/13 Then, the artificial leather was treated with hydrosulfide 1 so/l, caustic soda 1 g/11 and amylazine 1 g/l.

Reduction washing was carried out at a bath ratio of 50:1 and a bath temperature of 80°C for 30 minutes, and the wash fastness and light fastness of the dyed product obtained by thorough washing with water and drying were measured in the same manner as in Example 3. Measured to be 3rd grade discoloration and fading, 1st to 2nd grade contamination (attached white cloth, cotton),
It was grade 1 (attached white cloth, nylon) and extremely poor.

Example 4 50 parts of the polyester chips with an intrinsic viscosity of 0.75 obtained in Example 2 and 50 parts of polyethylene were spun using a chip blend spinning method, and a multicomponent fiber obtained by stretching the fiber by approximately 3.5 times in hot water was obtained. A polyurethane 15% DMF was prepared by mixing 90 parts of polyester polyurethane and 10 parts of polyethylene ether polyurethane with an entangled nonwoven fabric having a weight of 750 g/rn obtained by needle punching and cross-wrapping the web.
After impregnation with the solution and wet coagulation, the polyethylene in the fibers was dissolved and removed and dried.

The obtained sheet-like material was sliced into two parts using a band machine knife and puffed with emery paper to obtain suede-like artificial leather with a raised layer formed on both sides.

This artificial leather was dyed and treated in the same manner as in Example 2.

That is, with the bath composition shown below, the bath ratio is 5Q:11 and the bath temperature is 1.
After dyeing with a disperse dye at 05°C for 90 minutes, perchloren solution (disperse dye solubility 5 below at room temperature)
The treatment was repeated twice at a bath ratio of 50:1 and room temperature for 10 minutes.

Dye Dianix Brown GS-E (C,1
, NO unknown) (manufactured by Mitsubishi Chemical Industries, Ltd.) Dye concentration 10% owf Disper TL li/l This treated artificial leather was washed with the bath composition shown below at a bath ratio of 50.
:1. Dyeing with a complex salt dye was carried out at a bath temperature of 90° C. for 60 minutes.

Dye: Irgalan Brown GRL] Dye concentration: 2% owf Next, soaping was carried out for 30 minutes at a bath temperature of 60°C with a bath composition of 1 g/l of monogen and 1&/l of sodium carbonate, and the dyed artificial leather was obtained by thoroughly washing with water and drying. The washing fastness was measured according to JIS-LO844゜A-2, and it was 5th grade for discoloration and fading, 5th grade for staining (attached white cloth, cotton), 4-5
grade (attached white cloth, nylon) and showed excellent firmness.

It also has excellent light resistance and is made of calf suede-like artificial leather with a textured texture.

Claims (1)

[Claims] 1. When dyeing artificial leather composed of a fiber entanglement consisting of polyester fibers and a binder consisting of a polyurethane polymer, the artificial leather dyed with a disperse dye is treated with an organic solvent that dissolves the disperse dye at a ratio of 59/1 or more at room temperature. A dyeing method with good wax property in a dyeing room, which is characterized in that the dyeing process is carried out with a 1:2 type complex salt dye.