JP2003342549A - Water-based matting and surface-treating agent of polyolefin sheet for vacuum molding, and polyolefin sheet for vacuum molding - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water-based matting and surface-treating agent for a thermoplastic polyolefin sheet for vacuum molding, containing water as a main solvent entirely or almost free from an organic solvent, and forming a film having excellent adhesiveness to a polyolefin sheet such as a TPO, excellent vacuum moldability and excellent abrasion resistance, and having excellent matte effects even after the vacuum molding. <P>SOLUTION: The water-based matting and surface-treating agent for the thermoplastic polyolefin sheet for the vacuum molding comprises an aqueous urethane-based resin obtained by using a polyol component containing a polyolefin polyol, and polyurethane fine particles as a matting agent. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyolefin sheet, and more particularly to a matte surface treating agent for a thermoplastic olefin sheet used for vehicle interior materials and a matte surface treated thermoplastic olefin sheet.

[0002]

2. Description of the Related Art Vehicle interior materials (instrument panels,
Vinyl chloride resin sheets have been mainly used for door trims, etc., but thermoplastic polyolefins such as
Conversion to a thermoplastic polyolefin-based elastomer (TPE) called TPO is being promoted.

However, TPO has extremely poor surface wear resistance and oil resistance as compared with conventional vinyl chloride resin sheets, and TPO has improved wear resistance and oil resistance and is designed as an interior material. In order to impart the property, it is surface-treated with a urethane resin surface treatment agent, and is molded into an interior material by vacuum molding. Also, since TPO has poor surface activity,
Although surface activation is performed by corona discharge treatment, there is no urethane resin surface treatment agent that can be directly adhered to the activated TPO, and a two-layer coat is generally used in which the treatment agent is applied after primer treatment. It is a processing system. This processing system is currently all solvent-based, and the primer used is mainly chlorinated polypropylene (although some 2-component urethane resin-based primers are also used), devinyl chloride The processing system is inconsistent with resinization.

On the other hand, vehicle interior materials dislike diffuse reflection of light in order to create a more calm atmosphere than before, and the surface treatment agent is full mat (matte). Generally, silica powder is used as the matting agent. The surface-treated TPO sheet is formed into a member by vacuum forming, but gloss extension occurs due to the extension of the forming at this time. In anticipation of this, we are trying to suppress the gloss after molding to the required range by increasing the blending amount of silica powder. However, if a matte feeling is strongly demanded, for example, when silica powder / urethane resin (weight ratio) exceeds 0.5, silica powder is often used. It becomes impossible to use. Under such circumstances, there is a strong demand for a matte surface treating agent having a high moldability and capable of retaining a high matte (high degree of matte) that gives a high-grade feeling even after vacuum forming.

Further, the current surface treatment systems as described above are all treatment systems using organic solvents, and in order to suppress VOC (volatile organic compound) emissions from the viewpoint of protecting the global environment. There is also a strong demand for the development of a water-based coating system containing water as a main component in which the use of an organic solvent is suppressed as much as possible, preferably using only water as a solvent.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to prepare a TPO containing water as a main solvent, which contains no or almost no organic solvent. Aqueous matte surface for polyolefin sheet for vacuum forming that forms a film that has excellent adhesion to polyolefin sheet, excellent vacuum formability, abrasion resistance, oil resistance, and excellent matteness even after vacuum forming. It is to provide a treating agent.

[0007]

In order to achieve the above object, the present inventors have developed a urethane resin having water-based adhesiveness to a TPO sheet and properties as a surface treatment agent and a matting agent excellent in moldability. As a result of earnest research for development, the present invention has been completed. According to the present invention, an aqueous matte surface treating agent for a polyolefin sheet for vacuum forming, which comprises an aqueous urethane resin using a polyol component containing a polyolefin polyol and polyurethane fine particles as a matting agent, and the matte surface described above. Provided is a polyolefin sheet for vacuum forming, which has a coating film formed of a treating agent.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail below. The polyolefin sheet targeted by the present invention is a low-density to high-density polyethylene (LDPE, LLDPE, H
Sheets of polyolefin resin such as DPE), polypropylene (PP), polyethylene-propylene copolymer, poly-4-methyl-pentene-1, etc., soft segment polyolefin rubber (mainly EPR, EPDM)
Etc.) and hard segment polyolefin resin (mainly PP etc.) TPO (thermoplast)
Examples include sheets of ic polyolefin), blends of polyolefin-based resins and olefin-based rubbers such as EPDM and EPR, and sheets of alloys, and sheets including polyolefins other than these are also included.
Of these, TPO sheets are preferred.

The aqueous matte surface treatment agent for a vacuum forming polyolefin sheet of the present invention (hereinafter sometimes referred to as an aqueous surface treatment agent) is used for adhesion to a polyolefin sheet with little or no organic solvent. Excellent in
It is an excellent water-based matte surface treating agent which forms a film having excellent abrasion resistance and oil resistance on a polyolefin sheet, has excellent vacuum formability, and retains a high degree of matteness even after vacuum forming.

In order to exhibit such excellent effects, the aqueous surface treatment agent of the present invention is an aqueous solution comprising an aqueous urethane resin using a polyol component containing a polyolefin polyol as a film forming component and polyurethane fine particles as a matting agent. The feature is that a surface treatment agent is used.

The polyolefin polyol used in the production of the aqueous urethane resin of the present invention (meaning an aqueous urethane resin dispersion) is obtained by saturating the double bond of 1,2- or 1,4-polybutadiene polyol with hydrogen. Polybutadiene, which is a modified polyolefin polyol, includes homopolymers of butadiene and monomers copolymerizable with polybutadiene, such as ethylene, styrene, vinyl acetate, (meth) acrylic acid ester, and acrylonitrile. Be done.
The content of butadiene units in the copolymer is preferably 50% by weight or more from the viewpoint of adhesiveness with the polyolefin sheet. The average molecular weight of the polyolefin polyol is not particularly limited, but the average molecular weight is preferably 500 to 4000. Such polyolefin polyols are commercially available products (such as Polytail H and HA manufactured by Mitsubishi Chemical Corporation) and are available.

The polyolefin polyol is 20 to 8 out of all the polyol components used in the production of the aqueous urethane resin.
It is used in a proportion of 0% by weight, preferably 30 to 70% by weight. If the amount is too small, the adhesion to the polyolefin sheet is not sufficient, and if the amount is too large, abrasion resistant and oil resistant coatings cannot be obtained.

As the polyol used together with the above-mentioned polyolefin polyol in the production of the aqueous urethane resin used in the present invention, any polyol conventionally used in the production of urethane resins such as polyester polyol and polyether polyol is used. Although it can be used and is not particularly limited, a polycarbonate polyol such as polyhexamethylene carbonate polyol is particularly preferable in order to satisfy the performance required for the vehicle interior material. Polycarbonate polyol has an average molecular weight of 500 to 400.
0 is preferable.

Examples of the polyisocyanate compound used for producing the aqueous urethane resin of the present invention include tolylene diisocyanate, diphenylmethane diisocyanate (MDI) and xylylene diisocyanate (XD).
I), aromatic diisocyanates such as naphthylene diisocyanate; aliphatic diisocyanates such as 1,6-hexane diisocyanate; conventionally known polyisocyanates such as isophorone diisocyanate (IPDI), alicyclic isocyanates such as hydrogenated MDI and hydrogenated XDI. In consideration of the performance required for the vehicle interior material, an alicyclic or aliphatic diisocyanate having excellent weather resistance is preferable.

The method for producing the aqueous urethane resin used in the present invention is not particularly limited, and a polyurethane prepolymer produced by reacting a polyol and a polyisocyanate in the presence or absence of a solvent is used with a surfactant. To mechanically disperse in water (if a solvent is used, disperse the solvent and then remove the solvent), the above-mentioned polyurethane prepolymer (terminal NCO group) and 2,2-dimethylol-
Propionic acid, 2,2-dimethylol-lactic acid, 2,2-
Known methods such as a method of reacting with an active hydrogen-containing compound having an anionic salt-forming group such as dimethylol-butanoic acid, adding the reaction product to an aqueous solution of a neutralizing agent to emulsify and disperse, and, if necessary, extend the chain with polyamine Any of the water-based urethane-based resin production methods of can be used.

Polyurethane fine particles as a matting agent which is another essential component in the present invention are oils and fats obtained by esterifying a hydroxyl group-containing fatty acid (ricinoleic acid, 12-hydroxystearic acid, etc.) with glycol in a non-aqueous solvent. Polyurea colloidal particles obtained by a method of reacting a prepolymer obtained by reacting a modified polyol with a polyisocyanate at a specific NCO / OH equivalent ratio and a polyamine are used as an emulsifier with a conventionally known polyol in an inert solvent. Polyurethane fine particles whose surface is produced by the method described in JP-A-7-97425 in which polyisocyanate is reacted are coated with polyurea colloid particles. Although there are commercially available polyurethane beads, all of them have insufficient heat discoloration resistance and cannot be used as matting agents for vehicle interior materials. The average particle diameter of the urethane particles coated with polyurea colloidal particles is usually about 0.5 to 100 [mu] m, full matte polyolefin sheet for a vehicle interior material ^(60. Specular gloss than 1.2) Is required, it is preferably 5 μm or less.

The water-based matte surface treating agent of the present invention includes silica, polycarbonate beads, acrylic resin beads, which have been conventionally used together with the above-mentioned polyurethane fine particles.
A matting agent such as silicone resin beads can be used in combination. In order to obtain an aqueous surface treatment agent having excellent vacuum formability, the content of the above-mentioned polyurethane fine particles in all matting agents must be 50% by weight or more, preferably 70% by weight or more. Matting agent is urethane resin non-volatile (solid content)
It is usually used in a proportion of 60 to 120 parts by weight per 100 parts by weight.

The aqueous matting surface treating agent of the present invention can be obtained by mixing an aqueous urethane resin and a matting agent, but if necessary, a crosslinking agent, a coloring agent, a defoaming agent, a leveling agent and the like are blended in necessary amounts. can do. Aqueous matte surface treatment agent
Usually, it is used as an aqueous dispersion having a nonvolatile content of 5 to 20% by weight. The water-based matte surface treating agent of the present invention has a viscosity adjusted using a thickener, and is applied onto a polyolefin sheet by a coating means such as gravure or spray so that the dry thickness is about 2 to 5 μm. After drying, usually 50 to 120
A film is formed by heat treatment at a temperature of about ℃. The polyolefin sheet on which the aqueous matte surface treatment agent coating of the present invention is formed in this manner is processed into a predetermined shape by vacuum forming.

[0019]

EXAMPLES The present invention will be specifically described below with reference to production examples, examples and comparative examples. The parts in the following text are parts by weight.

Production Example 1 Olefin polyol (Polytail HA manufactured by Mitsubishi Chemical Corporation:
Average molecular weight 2000, OH number 56.1) 1000 parts and D
Charge 74 parts of MBA (dimethylolbutanoic acid),
After heating to 0 ° C., 393 parts of hydrogenated MDI was added and reacted at 90 ° C. for 5 hours under a nitrogen stream to obtain a carboxyl group-containing terminal isocyanate prepolymer. This is TE
An emulsion was obtained by pouring into 255 parts of ion-exchanged water at 25 ° C. containing 51 parts of A (triethylamine) while vigorously stirring with a homomixer. Further, ion-exchanged water 810 having 81 parts of IPDA (isophoronediamine) dissolved therein
Of the semi-transparent milky white non-volatile content 30.2%, and the viscosity at 20 ° C. is 88 mPa · s.
A polyurethane dispersion of (88 cps) was obtained. Hereinafter, this dispersion is abbreviated as an aqueous polyurethane (a).

Production Examples 2 to 7 In the same manner as in Production Example 1, the raw material components shown in Table 1 and the amounts (parts) used were 6 types of aqueous polyurethanes (b) to (g).
Was synthesized. Table 1 also shows the properties of these aqueous polyurethanes.

[0022]

The aqueous polyurethanes (a) to (g) obtained in Production Examples 1 to 7 were applied to a TPO sheet, and the adhesion with the TPO sheet and the surface abrasion resistance were evaluated by the following methods. A TPO sheet treated by corona discharge was coated with each of the water-based polyurethanes (a) / (b) having different blend ratios and the water-based polyurethanes (c) to (g) (dry thickness: 3).
μm) and 90 ° C. to give a polyurethane coating and T
The adhesion with the PO sheet and the abrasion resistance were evaluated. The results are shown in Tables 2 and 3.

(1) The 180 ° peeling force is measured by adhering the adhesive surfaces. The results are shown below. X: less than 1 kg / cm. Δ: 1.0 to 1.5 kg / cm. ◯: Over 1.5 kg / cm. (2) Surface abrasion resistance Using a plane abrasion tester, No. 6 canvas is rubbed with a load of 1 Kgf, and the number of times until scratches are generated is measured. The results are shown below. X: 100 times. Δ: 2000 times. ◯: 5000 times.

[0025]

[0026]

From the above evaluation, as the polyol component used in the production of the aqueous polyurethane, the mixing ratio of the polyol is (a) olefin polyol / (b) polycarbonate polyol = 30/70 to 70/30 (weight ratio).
Is preferred.

Examples 1 to 6 and Comparative Examples 1 to 5 A mixture of aqueous polyurethane (a) / (b) = 50/50 (nonvolatile content weight ratio) and aqueous polyurethane (e) were used as vehicles, and Table 4 An aqueous surface treating agent was prepared with the formulation described in 1 above, and the suitability for the surface treating agent was evaluated by the following method.
The results are shown in Tables 4 and 5.

(1) Preparation of Samples Each surface treatment agent was applied onto a TPO raw fabric that had been subjected to corona discharge treatment so that the film thickness after drying was about 3 μm, and dried for 2 minutes in a dryer at 80 ° C., Leave it for 1 day at room temperature and ripen, then 160 ℃
And 180 ° C. vacuum forming machine respectively. (2) Evaluation method Moldability evaluation: The surface of the sample before and after vacuum forming is visually and visually observed with a magnifying glass (100 times) to confirm the occurrence of a whitening phenomenon and a cracking. If there is no occurrence of these, ○, if there is even a little ×. Gloss value: Measured with a gloss meter according to JIS K5600, and a gloss value of 1.2 or less (a standard value required by the industry) is regarded as acceptable. Scratch resistance: When scratches with a nail, scratches or whitening do not occur, it is indicated by ○, and when these occur, it is indicated by ×.

[0030]

[0031]

(Note) (1) Dainichiseika Kogyo Co., Ltd. Dymic beads UCN-5030 (2) Dainichiseika Co., Ltd. Dymic beads UCN-510
0 (3) Nipseal E220A manufactured by Nippon Silica Industry Co., Ltd. (4) Mechanical crushing prototype

[0033]

According to the present invention, VO containing no organic solvent is used.
It is water-based with C countermeasures taken, and can be applied directly (without primer coating) to a polyolefin sheet such as a TPO sheet to obtain a coating having excellent adhesion, and the coating exhibits excellent vacuum forming performance, Provided is an aqueous matte surface treatment agent that retains excellent matteness even after vacuum forming. Therefore, the aqueous matte surface treatment agent of the present invention is useful as an aqueous surface treatment agent that can supplement the drawbacks of polyolefin sheets such as TPO sheets, which will be the mainstay of future vehicle interior materials.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Katsuyuki Fukui             1-7-6 Nihonbashi Bakurocho, Chuo-ku, Tokyo               Dainichi Seika Kogyo Co., Ltd. (72) Inventor Tetsuya Tako             1-7-6 Nihonbashi Bakurocho, Chuo-ku, Tokyo               Dainichi Seika Kogyo Co., Ltd. F-term (reference) 4F006 AA12 AB37 BA14 CA04 DA02                       EA03                 4F100 AK03B AK51A BA02 BA07                       BA15 DE01A GB33 JB05A                       JL01 JL11

Claims (5)

[Claims] 1. An aqueous matte surface treating agent for a vacuum forming polyolefin sheet, comprising an aqueous urethane resin using a polyol component containing a polyolefin polyol and polyurethane fine particles as a matting agent. 2. The aqueous matte surface treating agent for a vacuum forming polyolefin sheet according to claim 1, wherein the content of the polyolefin polyol in the polyol component is 20 to 80% by weight. 3. The aqueous matte surface treating agent for a vacuum forming polyolefin sheet according to claim 1, wherein the polyolefin polyol is a hydrogenated product of polybutadiene polyol. 4. The matte surface treating agent for a vacuum forming polyolefin sheet according to claim 1, wherein the surface of the polyurethane fine particles is coated with polyurea colloid particles. 5. A polyolefin sheet for vacuum forming, which has a coating formed on the surface thereof with the water-based matte surface treating agent according to claim 1.