JPS5849732A - Preparation of ink-holding porous material - Google Patents

Abstract

PURPOSE:To obtain the titled tough porous material having improved abrasion resistance and dimensional stability and good elasticity and porosity, by applying a powdery or liquid bonding organic elastomeric material to the surface of a structural powdery material, and packing the material in a mold, and hot- pressing the material. CONSTITUTION:A powdery or liquid bonding organic elastomeric material is applied to the surface of a structural powdery material consisting of an inorganic powder, e.g. carbon black, silica or talc, or thermoplastic elastomeric powder, e.g. polyurethane, and the resultant material is packed in a mold and hot-pressed to mold a porous material, which is then impregnated with an ink to afford an ink holding porous material, e.g. an ink roll or ink pad. A thermoplastic resin powder, molten thermoplastic resin or rubber, liquid thermosetting resin or reactive liquid rubber may be cited as the organic elastomeric material. EFFECT:The desired porosity can be obtained, and the quantity of energy to be used can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel method for producing an ink-retaining porous body. More specifically, the present invention relates to a method for producing ink-retaining porous bodies such as ink reels and ink pads that are strong, have excellent abrasion resistance and dimensional stability, and have good elasticity and porosity.

Traditionally, ink-retaining porous materials such as ink seals and ink pads have been manufactured using acrylic, ethyl-butadiene rubber, and polyurethane.

Polymer powder, such as polymer powder, is filled into a mold, heated and sintered at high temperature to form a porous body having fine pores, and then impregnated into the porous body. The so-called sintering method is well known.

However, just as mentioned above! - In the sintering method that integrates powders, sintering requires a large amount of heat, and achieving the desired porosity is achieved by dissociation, which achieves the desired inter-impregnation rate and excellent ink ejection properties. There is a drawback that it is not possible to produce a porous body that is strong and has appropriate elasticity.

The present invention was completed in order to eliminate the disadvantages in price, and its gist is to apply powdered or liquid bonding material to the surface of structural powder leaf material made of inorganic powder or thermoplastic elastomer powder. The gist of the present invention is a method for producing an ink-retaining porous body, which is characterized in that after an organic elastic material is attached, the porous body is formed by heating and impregnated with ink. .

That is, the method of the present invention applies a powdered or liquid material to the surface of a structural powder material that is strong, has excellent wear resistance, and dimensional stability, and is softened or hardened by heating to firmly bond adjacent powder materials. This method is characterized by thermoforming a composite material to which an organic elastic material is attached.

The structural powder material may be an inorganic powder, a thermoplastic elastomer powder, or a mixture thereof.

Inorganic powders include, for example, soft inorganic powders with excellent compression properties such as carbon platter and calcium carbonate% calcium sulfite, hard inorganic powders with excellent tensile strength such as silica, aluminum silicate, and clay, and titanium. Potassium acid.

Examples include materials that increase tensile strength and compressive properties, such as plastonite, tarta, and mica.

Examples of the thermoplastic elastomer powder include polyurethane and acryl ms-silyl-butadiene rubber.

Among the organic elastic materials for bonding in the present invention, powdery ones include, for example, thermoplastic resin powder, and liquid ones include, for example, molten thermoplastic resin, thermoplastic rubber, liquid thermosetting resin, or Examples include reactive liquid rubbers.

Examples of the thermoplastic resin powder and the molten thermoplastic resin include &') vinyl chloride, polyethylene, polyethylene terephthalate, and polybutylene terephthalate.

Melting and softening materials such as meliamide and laryamide copolymers are scorched. Further, examples of thermoplastic rubbers include polyurethane, Aku-9W Disilylubutadiengo-5, and the like.

Examples of liquid thermosetting resins include polyurethane, epoxy resin, unsaturated polyester, and diaryl 7-thalerate resin.

Furthermore, examples of the reactive liquid rubber include liquid urethane rubber, liquid butadiene-styrene rubber, liquid nitrile-butadiene rubber, and liquid prene rubber. These are mainly used for surface fitting of structural powder materials.Next, a method for surface treatment II (adhesion) of the structural powder materials using each of these bonding elastic materials and a molding method thereof will be described.

The thermoplastic resin powder, which is a powdered organic elastic material for bonding, is preferably mixed with the powder material so that it adheres entirely to the surface of the structural powder material or with some gaps. Yes. FIG. 1 is a schematic cross-sectional view showing an example of a state in which the thermoplastic resin powder* of the present invention is attached to a structural powder material, in which fine particulate thermoplastic resin powder ( 2) are attached to each other with gaps as shown in Fig. 1, the resulting porous body can have an extremely large porosity, and the amount of organic elastic material (z) mixed can be changed as appropriate. This has the excellent advantage that a porous body having a desired porosity can be obtained. The structural powder material (1) preferably has a particle size of 8 to 180p and is spherical or nearly spherical (for example, elliptical).

Also thermoplastic resin powder 311! The particle size of (g) is preferably about 1 to 10 5 with respect to the particle size of the structural powder material (1).

Also, the amount of thermoplastic resin powder) to be mixed with the structural powder material (1) is thermoplastic elastomer as the powder material! - When using an inorganic powder, it is preferably 25% (wt%, the same applies hereinafter) or less of the total amount, especially 6 to 15%, and when using an inorganic powder, it is preferably 10 to 50% of the total amount. It is preferable that P<20 to 35 Ha. If the amount of the thermoplastic resin powder (8) mixed exceeds the above range, the resulting porous body will be soft and have poor wear resistance and dimensional stability; if it is less than the above range, the structure will deteriorate. Powder material (1) is undesirable because it has poor mutual strength and elasticity.

As a method for attaching the thermoplastic resin powder (2), for example, the thermoplastic resin powder (2) used for the structural powder material (1) may be
2) is heated to a temperature slightly lower than the melting point of the thermoplastic resin powder (2), and mixed with the thermoplastic resin powder (2) heated close to the melting point under an air flow until they fall, causing them to collide with each other.
There are several ways to attach it.

The structural powder material (1) that has been surface-treated in this manner is uniformly filled into the mold by a pressureless filling method using a vibrator, and a porous body sintered by heat treatment with hot air can be seen. Thus, the present invention has the advantage that the amount of heat required for sintering can be extremely reduced.

Note that as an organic elastic material for bonding, a polymer powder that is melted under pressure (for example, 7-Tsu-Tsu modified isobutylene, Gut-Tsu & quality isoprene rubber, etc.) can be used in place of the heat-melt resin powder.
may also be used. It takes a yellowtail! - The powder has the advantage that it does not need to be heated, since it adheres under pressure.

On the other hand, when the above-mentioned liquid materials are used as organic elastic materials for bonding, ``these liquid materials adhere to the surface of the structural powder materials so as to cover them, and the powder materials are bonded to each other by thermoforming. It imparts elasticity and is particularly suitable for use when inorganic powder is used as the structural powder material.

The liquid organic elastic material for bonding is mixed with the structural powder material in a liquid state in advance, and then filled into the mold, or each material is put into the mold.
Methods such as mixing and using are available. When a thermoplastic resin is used as the organic elastic material for bonding, the thermoplastic resin is mixed with the structural powder material in a heated and molten state, and then cooled and turned into a molten material in a mold. In addition, liquid thermosetting resins and resins are polycondensed and cured by heat molding in a mold, and flexible liquid rubbers are similarly crosslinked by heat treatment in a mold.

Hardened.

In order to attach these bonding organic elastic materials to the structural powder material, it is possible to completely cover the entire surface of the powder material, but for example, as shown in FIG. You can do it like this. In addition, in the case of complete coverage, the thickness of the organic elastic material for bonding is 1/2 of the material used.
If the structural powder material serving as the core material is an inorganic powder, the blending amount of the elastic material may be 10 to 50% of the total amount, especially if the structural powder material serving as the core material is an inorganic powder. It is preferably <20~6S, and thermoplastic elastomer! - In the case of powder, it is preferable that the amount of the powder be 5 to 15% of the total amount.

In order to improve the adhesion between the structural powder material and the organic elastic material for bonding, titanate coupling agents such as Isopfyo Bilt 9 (di-ctyl phosphate) titanate and isobutyl triisostearyl titanate are used. ,
Furthermore, it is preferable to use a coupling agent such as a silane coupling agent, a zirconate coupling agent, an altriolium coupling agent, or a calcium coupling agent. Such a coupling agent improves the surface adhesion of the inorganic powder, imparts strong adhesive strength, and when mixed with the thermoplastic resin powder, improves plasticization and lowers the softening temperature, Furthermore, it acts as a viscosity modifier for the liquid organic elastic material and also functions as a curing catalyst.

The shape of the structural powder material in the present invention is spherical.

- Various shapes such as fibrous shape and plate shape (flake shape) are preferably employed.

For example, if the structural powder material is approximately spherical, the powder material in the mold will be filled with the second! i
! ff, but if the thermoplastic resin powder (2) is arranged on the surface with appropriate gaps as shown in Fig. 1, the arrangement as shown in Fig. 6 is obtained. Therefore, the porosity can be made extremely large. By the way, in the arrangement shown in Figure 2, the porosity is about 25%, but in the case of the arrangement shown in Figure 6, it is possible to increase the porosity to 60-75%. be.

The structural powder material is fibrous (e.g. potassium titanate,
7. Single crystal fiber such as Test Nye F with an aspect ratio of 1.
0 to 50 mushrooms and diameter of 15 to lsOμ), the strength can be increased uniaxially by blending them, but by filling them into the mold without orientation, it is possible to enlarge the voids. can. In addition, inorganic fibers include organic fibers (for example, aromatic boacetate fibers such as DuPont's Kepler fiber, carbon fibers, datephyte fibers,
It is preferable to use a mixture of ester fibers, etc., in order to increase toughness.

In addition, plate-like powder (for example, kaolin, talc, etc. 1) A typical example is squid, which has a width of 1.4 to 4P, a thickness of 40μ or less, 1 usually 2 to hp, and its flake aspect ratio. is 41 to 100; 1), it may be filled into the mold in a non-oriented or uniaxially oriented manner, as in the case of the fibrous material. Furthermore, by using structural powder materials having each of these shapes in combination, the porosity can be increased.

In the present invention, after filling a mold with a structural powder material and an organic elastic material for bonding, the organic elastic material for bonding is rapidly melted and sintered, and then cooled and hardened. In order to shorten the time, it is preferable to preheat by irradiating far infrared rays or the like.

After heat molding, the resulting porous body is immersed in a mixed solution of an organic elastic material, a solvent such as alcohol, acetone, benzene, xylene, dimethylformamide, etc., and a non-solvent such as water, preferably the vapor of these solvents. It is preferable to remove or shrink the thin film on the surface of the porous body by bringing it into contact with the porous body to form fine pores and to form a uniform l-lath. For impregnating the porous body with ink, an ink impregnation method employed in ordinary ink pads and ink W-rules can be suitably employed.

As described above, the present invention allows bonding organic elastic materials to be attached to the surface of structural powder materials having various shapes, and sintering under much lower temperature conditions than normal sintering conditions using inorganic powders. Structural powder materials are firmly bonded by short-time heat and pressure molding under the same conditions, and have the excellent properties of structural powder materials such as toughness, abrasion resistance, and dimensional stability. The ink-filled toe has the excellent advantage that a porous body having voids of a size suitable for use as an interpad can be easily manufactured.

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

Example 1 Almost spherical thermoplastic urethane elastomer with an average particle size of 1 Sμ
Strike! - Powder and almost spherical polyvinyl chloride powder with an average particle size of 2μ are mixed in a fluidized immersion bath so that the amount of polyvinyl chloride powder is 10% of the total amount to form a thermoplastic urethane eth-shimmer. Polyvinyl chloride powder was attached to the surface of the powder. That is, first, a predetermined amount (600 liters) of 19-vinyl chloride powder was put into a fluidized immersion tank, and 140~
120-150 while stirring under 16G'0 (F) hot air
A predetermined amount of thermoplastic urethane elastomer powder preheated to
Thermoplastic urethane elastomer powder! - and then cooled.

While warming the leaked product by irradiating it with far infrared rays, it was filled into a mold using a non-pressure filling method using a vibrator.
70'O (1, blowing mature hot air for 5 minutes, diameter 20cm
A cylindrical porous body with a diameter of 40 cm and a length of 40 cm was molded. After molding, the porous body was crushed in a mixture of 80 parts of dimethylformamide and 20 parts of water to remove the surface film, and after forming into Zetes, it was dried. Then, an ink-retaining porous body was obtained by impregnating it with oil-based ink.

Example 2 Example 1 except that the amount of 19-disintegrated vinyl powder mixed with thermoplastic urethane etsshimmer powder was 6 times the total amount.
An ink-retaining porous body was obtained in the same manner as described above.

Example Black surface of spherical calcium sulfite powder with average particle size top
*-τT8 (isopropylene titanate manufactured by Kenrich Beto Chemical Co.) was coated at a ratio of 0.5 parts of calcium sulfite powder.

Next, almost spherical thermoplastic urethane elastomer with an average particle size of 6p)! - Mix the granular powder with the calcium sulfite powder in a fluidized dipping bath in the same manner as in Example 1 so that the amount is 26% based on the total amount, and the thermoplastic medium urethane elastomer powder is uniformly adhered to the surface of the calcium sulfite powder. After that, the mold was filled and the ink was stored in the same manner as in Example 1. Example 4 On the surface of heavy calcium carbonate powder with an average particle size of 8p! j
-TTS was coated with the heavy calcium carbonate powder at a ratio of 0.5 arc.0 The method was carried out in which the obtained heavy calcium carbonate powder was mixed with thermoplastic urethane elastomer powder at a ratio of 40 arcs to the total amount. An ink-retaining porous body was obtained in the same manner as in Example 1.

Comparative Example Naidan 6 powder with an average particle size of 6 Sμ was filled into a mold, preheated and molded under pressure at 160 oo for 10 minutes, and then fired for 6 minutes in a hot atmosphere of 26 G'O. The porous body was cooled and dried, and then impregnated with oil-based ink to obtain an ink-retaining porous body.

The toughness, abrasion resistance, and porosity of each ink-retaining porous body obtained in Examples 1 to 4 and Comparative Example were examined. The results are shown in Table 1. The test conditions for each test item in Table 1 are as follows.

(1) Toughness Tensile strength and elongation were measured according to the tensile test method described in 718 K 6301. Tensile stress was measured using a test piece (outer diameter 44.6 mm, inner diameter &6.
The tensile load was determined by measuring the tensile load when an elongation of 50 arcs was applied to the specimen (6mφ, length 57.5M).

(2) Wear rate The degree of wear was measured in accordance with the British standard ya890iS% Rem 90 method.

That is, the sample (thickness 10cm,
The wear rate of 1-4 kg (S bond) was determined for the width (14 cm).

(3) Porosity The porosity was determined using the following formula.

W! Table 1 Example 5 While stirring spherical calcium sulfite powder with an average particle size of 5 μm in a high shear stirrer, melted Naidan 66 was added to the total amount of porous body aS without ink. The surface of the calcium sulfite powder was coated by spraying it in a mist at a rate of 20 times.

Then it was cooled.

The resulting coated calcium sulfite powder was struck and vibrated with a ribbon blender to sufficiently loosen the agglomerated powder, and then a predetermined amount was filled into a mold with a gap of 20 mm in diameter and 40 mm in length. After heating and forming under pressure at 200° O for 5 minutes, the porous body was left to cool. This material was impregnated with oil-based ink to obtain an inter-porous material.

Example 6 While stirring spherical calcium sulfite powder with an average particle size of 10 μm in a high shear stirrer, a curing agent (liquid The surface of the calcium sulfite powder was coated by pouring 3 parts by weight of liquid urethane) into a thread at a rate of 15% of the total amount. After sufficiently loosening the agglomerated powder by applying blows and vibrations, the amount of the powder was filled into a mold with a gap of 25-1 in diameter and 50 m in length, and heated at 100 ° 0 for 5 minutes to form a porous body. I got it. This material was impregnated with oil-based ink to obtain an ink-retaining porous material.

Example A While stirring spherical calcium sulfite powder with an average particle diameter of tzp in a high shear stirrer, a reactive liquid rubber composition (Heika-Atyaw 1300 ) 143 parts by weight, 24 parts by weight of bisphenol (M extender), 100 μl of resin Rk (manufactured by EiiWA + Michal) 100
Inject a composition containing 100 parts by weight of the resin curing agent RM 10B (manufactured by Country 11 Cal) at a rate of 10% of the total amount using a fixed metal dispensing machine, The surface of calcium sulfite powder was coated.

The obtained coated calcium sulfite powder was blended with a ribbon blender in the same manner as in Example 5, filled into a mold, and blended at 40'O for 7.5 minutes, and further blended at room temperature for 6 minutes.
A porous body was obtained by curing for 0 minutes.

This material was impregnated with oil-based ink to obtain an ink-retaining porous material.

The toughness, abrasion resistance, and porosity of each of the ink-retaining porous bodies obtained in Practical Examples 6 and 7 were examined in the same manner as in Examples 1 to 4 above. The results are shown in Table 2.

No. 2511 In addition, the ink-retaining porous bodies obtained in Examples 1 to 7 were excellent in oozing out of the ink contained in the fine pores, and in particular, were excellent in ink extrusion under slight pressure.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-section WBWJ showing an example of the state in which the thermoplastic resin powder of the present invention is attached to the structural powder material;
The figure is a schematic explanatory diagram showing the arrangement of spherical structural powder materials in the mold, and FIG. 3 is a cross-sectional view showing the arrangement of the structural powder materials shown in FIG. 1 in the mold. (Drawing code) (1): Structural powder material (2): Thermoplastic resin powder

Claims (1)

[Scope of Claims] 1. A powdered or liquid organic elastic material for welding is adhered to the surface of a structural powder material made of inorganic powder or thermoplastic elaszimer powder, and then filled in a four-fold,
A method for producing an ink-retaining porous body, which comprises molding the porous body by heating and pressurizing it, and then impregnating it with an interlayer. 2. The method according to claim 1, wherein the powdery organic elastic material for welding is a thermoplastic resin powder. 6. The liquid organic elastic material for welding is a molten thermoplastic resin, thermoplastic rubber, or liquid. 2. The method according to claim 1, wherein the resin is a thermosetting resin or a reactive liquid rubber.