JPS5855175B2 - Method for manufacturing ink-retaining porous material - Google Patents

Description

[Detailed description of the invention] The present invention relates to a novel method for manufacturing an ink-retaining porous body.

More specifically, the present invention relates to a method for producing ink-retaining porous bodies such as ink rolls and ink pads that are foamed and cured at room temperature and contain ink in continuous micropores.

Conventionally, methods for producing ink-retaining porous bodies such as ink rolls and ink pads have mainly involved sintering granular or powdered polymers, or molding polymers with water-soluble salts, and then eluting the salts. A method has been adopted in which a porous body having continuous fine pores is formed, and then ink is impregnated into the porous body.

However, in these methods, forming the porous body and impregnating the ink must be performed separately, which not only makes the process extremely complicated, but also makes it difficult to impregnate the porous body with the ink uniformly. This results in considerable variation in the ink content.

However, as a result of extensive research in order to eliminate the above-mentioned drawbacks, the present inventors have developed a liquid product in which a room temperature foamable liquid urethane prepolymer, a modifier for the prepolymer, and an ink are mixed and uniformly dispersed. When the ink is injected into a seventh field and foamed and cured at room temperature, the above-mentioned drawbacks are eliminated, and a predetermined amount of ink is contained in the continuous micropores, and the ink roll,
The present invention was completed based on the new discovery that it is possible to provide an ink-retaining porous body that can be suitably used as an ink pad.

That is, the present invention provides a completely new method for producing an ink-retaining rigid porous body, in which a liquid urethane prepolymer mixed with ink is foamed at room temperature during molding, and is then cured.

The room temperature foaming type liquid urethane prepolymer in the present invention usually includes a part A consisting of an isocyanate component and a polyether-type and/or polyester-type glycol component, a polyether-type and/or polyester-type glycol component, a blowing agent, Part B consists of a catalyst and a stabilizer.

Examples of the isocyanate component include tolylene diisocyanate (hereinafter referred to as TDI), diphenylmethane diisocyanate, bitolylene diisocyanate, and the like.

Further, the polyether type glycol component has a molecular weight of, for example, 2000 to 6000, more preferably 300.
0 to 4000 high molecular weight dipolyols or tripolyols (e.g. polypropylene glycol, polyoxypropylene glycol, trinotyrolpropane, 1,
2,6-hexane l-IJol, etc.).

Furthermore, the polyester type glycol component has a molecular weight of 2,000 to 6,000, for example. More preferably 30
Ethylene adipate and propylene saccharide, which are obtained by condensing acid components such as 00 to 4000 saturated polyester glycol C, such as adipic acid, maleic anhydride, and succinic acid, with glycols such as ethylene glycol, propylene glycol, diethylene glycol, and glycerin. etc.), and these can be used in combination with the polyether type glycol component as appropriate.

Examples of the blowing agent to be added to Part B include water and a fluorocarbon blowing agent, and it is particularly preferable to use water and a fluorocarbon blowing agent in combination. A solvent such as the following may be used in combination with water.

Such a blowing agent is blended in an approximately equal amount to the NCO content in the urethane prepolymer.

Further, as a catalyst, for example, a combination of a tertiary amine and a metal salt can be used.

Examples of tertiary amines include triethylenediamine, bis(2-dimethylamineethyl)ether, N-)f-rumorpholine, trialkylamine, N,N'-dimethylpiperidine, and examples of metal salts include dibutyltin dilaurate, Examples include stannous octanoate, but preferably a combination of triethylene diamine, bis(2-dimethylamine ethyl) ether and dibutyltin dilaurate, or N-methylmorpholine, N
, N'-dimethylpiperidine and stannath octanoate.

The amount of these catalysts used is
With respect to 100 mol% of O, the amount of tertiary amine is 0.3 to 3 mol φ, and the amount of metal salt is 0.01 to 0.07 mol%.

In addition, as a stabilizer, for example, an appropriate amount of silicone oil, silicone resin, and an interface such as an alkyl compound such as polyoxyethylene alkyl ether or polyethylene alkyl ferrate, or an oleic compound such as ethoxylated oleic acid or triethanolamine monooleate are used. Examples include one or a mixture of two or more surfactants, preferably silicone surfactants such as dimethyl silicone and methylphenyl silicone, alone or in combination.

Furthermore, in the present invention, mechanical properties such as tensile strength and compressibility of the porous body obtained can be improved by adding a reinforcing agent to part B in addition to these blowing agents, catalysts, and stabilizers.

Examples of such reinforcing agents include inorganic fine powders and inorganic single crystal fibers coated with a camping agent having a reactive monofunctional group. Examples include fine powders of calcium carbonate, silica, calcium sulfate, etc. with a size of 1μ or less, or single crystal fibers such as potassium titanate.

The coupling agent is used to adjust the viscosity of the urethane prepolymer, as well as to bridge and cure the prepolymer and these inorganic substances. Examples of the coupling agent having such a reactive monofunctional group include titanate, system coupling agents [for example, isopropyl tri(dioctyl pyrophosphate) titanate (trade name: KR38S) manufactured by Kenritsu Petrochemical Co., Ltd., titanium (
Dioctyl pyrophosphate) oxyacetate (trade name: KR-1388), isopropyl triisostearoyl titanate (trade name: KR-TTS), and isoprobyl isostearoyl di4-aminobenzoyl titanate (trade name: KR-37BS), etc.) Furthermore, various silane coupling agents, zirconate coupling agents, chromium coupling agents, etc. can be suitably employed.

In addition to these blowing agents, catalysts, stabilizers, and reinforcing agents if necessary, part B requires a developing agent such as a phthalic acid plasticizer, a commercially available flame retardant, an antistatic agent, a coloring agent, etc. It can also be added as appropriate.

For example, when parts A and B are mixed at a weight ratio of 1:1, the incyanate fraction in part A and the glycol fraction in part A are the urethane fraction. 7 to 13 in NCO in polymer
It is preferable to mix NC010E (in a molar ratio of 1 to 2:1) so that the amount is mol %, preferably 11 to 12 mol %.

The modifier in the present invention is used as an adjusting agent for the volume ratio (ratio of the porous body to the total volume, the same applies hereinafter) of the porous body obtained by foaming and curing the urethane prepolymer, and is the same as described above. A porous body obtained by foaming and curing only a urethane prepolymer has a low volume ratio and is not suitable for use as an ink roll or an ink pad.

Modifiers for the urethane prepolymer in the present invention include, for example, thermoplastic elastomers, room temperature crosslinking solid rubbers, reactive liquid rubbers, and reactive monomers, which may be used alone or in combination of two or more. It may also be used.

The thermoplastic elastomer and room-temperature crosslinking solid rubber have a function as a polymer extender, and the reactive liquid rubber and reactive monomer are themselves liquids, so they increase the viscosity of the urethane prepolymer. Moreover, when the prepolymer is cured, it reacts with the prepolymer to cause a crosslinking reaction, and has the function of adjusting the volume ratio of the resulting porous body.

Examples of the thermoplastic elastomer include styrene-butadiene block copolymer, thermoplastic polyester elastomer, thermoplastic polyurethane elastomer, polyethylene-butylcomb graft polymer, ethylene propylene diene methylene (EPDM), polyolefin blend polymer, and plasticized polyvinyl chloride. More preferred are thermoplastic polyurethane elastomers and styrene-butadiene block copolymers.

Examples of the room temperature crosslinked solid rubber include crosslinked solid rubbers that can be used in an uncrosslinked state, such as butadiene rubber, nitrile rubber, and chloroprene rubber.

These thermoplastic nidistomers and room temperature cross-linked solid rubbers are in the form of fine powder, and have a ratio of about 5 to 10% compared to the rubber content of the prepolymer.
It is added to the prepolymer within a range of 0% (weight %, the same applies hereinafter).

By adding in advance to these solid polymer powders a coupling agent having the same reactive monofunctional group as used for the reinforcing agent, the viscosity of the prepolymer can be adjusted and the prepolymer and the coupling agent can be adjusted. The prepolymer can be crosslinked and cured by molecular entanglement.

Examples of the reactive liquid rubber include liquid materials having a reactive group at the end, such as 1,2-polybutadiene, 1゜4-polybutadiene, nitrilecomb, chloroprenecomb, and one-component polyurethane, but more preferably Preferably, a one-component polyurethane rubber is used.

Examples of the reactive monomer include liquid materials such as styrene and acrylic monomers.

These reactive liquid rubbers and reactive monomers cause crosslinking of the urethane prepolymer during curing, and can provide an ink-retaining porous body having a desired volume ratio or porosity.

The amount of these modifiers to be added is such that the ratio of the resulting porous body to the ink contained in the micropores is 25, approximately 5 to 5.
The ratio of urethane prepolymer to modifier is usually 80:20 by weight, although it is determined appropriately based on the volume ratio of the urethane prepolymer when it is in a liquid state and the volume ratio after foaming and curing. -95:5 as appropriate.

When the amount of the modifier added is greater than the above range, the resulting porous body becomes hard, which is not preferable.

The ink used in the present invention uses a vehicle of various oils and fats such as vegetable oil, animal oil, mineral oil, synthetic oil, etc., and a colorant (dye, etc.) and a dispersant are added to the vehicle to form a liquid or paste at room temperature. It is preferable to use ink adjusted to .

Each of the ink components such as oils and fats, colorants, and dispersants are either incompatible with each other or not compatible with the porous body forming components such as the urethane prepolymer components and modifier components described above. Even if they are compatible with each other, they become incompatible with each other upon curing, resulting in a pressure exudable ink that is uniformly contained within the micropores of the resulting porous body.

The oils and fats include, for example, vegetable oils such as rapeseed oil, castor oil, and soybean oil, animal oils such as whale oil and cow leg oil, mineral oils such as motor oil and spindle oil, and olefin polymerized oils (such as ethylene hydrocarbon oils). , butylene-based hydrocarbon oil, etc.), polyalkylene glycol oil (addition polymer of alkylene oxide such as ethylene oxide or propylene oxide and aliphatic monohydric alcohol, or a copolymer thereof, such as Union Carbide & Carbon) (trade name: Ucon) manufactured by Ucon, etc.], diester oils (e.g., bis(2-ethylhexyl) sebacate, bis(1-ethylpropyl sebacate))
, azelaic acid (2-ethylhexyl), bis(2-ethylhexyl) adipate, etc.], synthetic oils such as silicone oil (for example, low-viscosity linear dimethylpolysiloxane, etc.), and fatty acids such as isostearic acid and oleic acid. can be given.

Examples of the colorant include dyes such as oil black, oil blue, oil red, methyl violet base, and nigrosine base.

Further, examples of the dispersant include sorbitan fatty acid ester, polyoxyethylene sorbicun fatty acid ester, glycerin fatty acid ester, propylene glycol fatty acid ester, polyethylene glycol fatty acid ester, polyoxyethylene alkyl ether, hydrogenated castor oil derivative, polyoxyethylene castor oil etc.

These oils and fats, colorants and dispersants each have a weight of 75 to
It is blended at a ratio of 95 parts (by weight, the same applies hereinafter), 5 to 20 parts, and 5 parts or less, preferably 0.1 to 2 parts.

The thus obtained ink of the present invention is mixed in a ratio of 50 to 75 parts with respect to the total amount of the urethane prepolymer and modifier of 25 to 70 parts to form a liquid.

In the present invention, a coupling agent having a directly reactive monofunctional group may be added to the liquid obtained by mixing the urethane prepolymer, modifier, and ink as described above; This has the advantage of improving the flow characteristics of the liquid material and of bonding and adsorption at the interface between the cured polyurethane rubber and the modifier.

As the coupling agent having such a reactive monofunctional group, for example, the same coupling agent used for coating the above-mentioned reinforcing agent can be used as is.

These coupling agents impart fluidity to the liquid substance, and improve the reinforcing effect of the modifier and/or reinforcing agent on the resulting porous body body.

Therefore, in the present invention, the amount of the coupling agent having a reactive monofunctional group added to the liquid is 0.1 to 1%, preferably 0.2 to 0.4%, based on the rubber content in the compounding. It is preferable that the coupling agent is in the range of 1 to 1, and can be used in place of or in combination with the use of a coupling agent having a monofunctional group reactive with the reinforcing agent and/or modifier as described above.

As described above, in the method of the present invention, since the ink is mixed in advance with a pore-forming material such as a urethane prepolymer or a modifier, the ink uniformly contains a predetermined amount of ink. The retention porous body can be obtained in just one step, the ink content can be changed arbitrarily, and the foam molding of the porous body is carried out at room temperature without heating, which makes it more effective than ordinary heat molding. It is extremely advantageous in terms of cost as it can save a large amount of energy, and there is no fear of fire, and it does not contain decomposition residues of organic compounds, such as those found in foams obtained by ordinary heat molding. Never.

In addition, in the method of the present invention, since the urethane prepolymer and ink, which are the main components, are in liquid or paste form, even if a solid substance is used as a modifier or the reinforcing agent is used, the It has excellent miscibility,
Furthermore, since these modifiers or reinforcing agents are used by modifying the surface with a coupling agent having a reactive monofunctional group, it is possible to mix and disperse them uniformly, and therefore the resulting porous material also has a similar shape. The fine pores are uniform, and the flow characteristics are also excellent, making it possible to uniformly fill even the smallest details of the mold, which has the remarkable effect of allowing molded products to be changed exactly as they were molded.

However, the ink-retaining porous body obtained in the present invention has the same micropores (approximately 5 to 5
As described above, the ink is uniformly contained within the micropores, and the ink does not scatter even during use.

The urethane polymer (A part and B'1l) in the present invention
After the modifier and ink are uniformly mixed and dispersed using a regular dispenser, they are injected into a predetermined mold and foamed and hardened at room temperature. I will explain about it.

The above-mentioned components can be mixed, for example: (1) urethane prepolymer A part to which a modifier has been added in advance, 8 parts of urethane prepolymer, and ink are placed in a dispenser, or (2) urethane prepolymer A part and urethane prepolymer part A and urethane prepolymer A part are mixed together. Either mix 8 parts of the polymer in advance and add the modifier and ink to the dispenser, or mix the urethane prepolymer A part, B part and the modifier in advance, then add the ink and put it in the dispenser. or (2) Add a modifier to the urethane prepolymer part B in advance, then add this, the urethane prepolymer part A, and the ink to a dispenser, and then mix them with the dispenser and inject a certain amount into the mold.

It is necessary to separate the A liquid and the B liquid in advance so that they do not react with each other.

In addition, when solid rubber is used as a modifier, it is preferable to mix it with liquid B and dissolve or disperse it in advance.

When a reactive liquid rubber or a reactive monomer is used as a modifier, it is referred to as liquid C.

Combine ingredients that do not react chemically into liquid B.

Inorganic powders and single crystal fibers treated with Naori Tubbling Agent (
When using a reinforcing agent), it is preferable to mainly use liquid rubber as the modifier and blend it to form Liquid C.

The ink is mixed with liquid B, alone in liquid C, or mixed or dissolved in reactive liquid rubber or reactive monomer.

The foaming effect of the liquid material consisting of each of these components is completed in about 5 to 15 minutes at room temperature.

In this way, an ink-retaining porous body containing a predetermined amount of ink uniformly within its continuous fine pores is obtained, which can be suitably used as an ink roll or an ink pad.

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

Example 1 The following formulations were used as parts A and B of a room-temperature foamable polyurethane polymer.

Ingredients Part by weight Part A TDI 382.8 Polypropylene glycol 1500.0 (molecular weight 30
00) Part B polypropylene glycol 1850.0 (molecular weight 38
00) Water 32.0 Carbon fluoride 20.0 Silicone oil
0.2bis(2-dimethylaluminum)
1.2 Noethyl) Ether dibutyltin laurate 0.45 total
3786.65 However, the NCO content in the bulk of the prepolymer was 7.25 mol.

When these urethane prepolymers A part and B part were mixed in a weight ratio of 1:1 and foamed and cured at room temperature, the resulting porous body had a volume ratio of 0.03.

On the other hand, an ink was prepared by mixing 0.2 parts of KR-388 with 10 parts of thermoplastic polyester elastomer as a modifier for 100 parts of component B of these urethane prepolymers, and an ink with the following composition. An ink consisting of was prepared.

Parts by weight Oil black 10 Nigejishin base 5 Methyl violet base
1 isostearic acid
40 mineral oil 44
Part A of the urethane prepolymer and the modified part B are the first component and the second component, respectively, in a weight ratio of 1:1), and the modified part 200 parts of the above ink was used as the three components.

These 1st to 3rd precepts were mixed with a dispenser, and the resulting liquid was discharged into a mold, with a rise time of 4 minutes and a gel time of 7 minutes (however, gelation was performed under heating at 40°C). A foaming effect was performed using the ink roll, and an ink roll having a volume ratio of 0.40 was obtained.

Example 2 The following formulations were used as polyurethane prepolymers A part and B part.

Part by weight Part A TDI Polyethylene glycol (molecular weight 3000) Part B 382.8 750.0 Polyethylene glycol (molecular weight 3975) 993.7 Castor oil 95.0 Water
26.07 carbon fluoride
10.0 silicone oil
0.2 triethylenediamine 1.
0 dibutyltin dilaurate 0.35 total
2493.05 However, the NCO content in the prepolymer hole is 12.58
It is a moru-kema.

When these urethane prepolymers A part and B part were mixed in a weight ratio of 1:1 and encapsulated and cured at room temperature, the volume ratio of the porous body obtained was 0.04.

On the other hand, the urethane prepolymer A part was used as the first component, and the same ink used in Example 1 was added to the urethane prepolymer B-HIIS in a total amount of 100 parts of the urethane prepolymer A and B parts and the following modifier. The second precept is a mixture of 150 parts of 150 parts of oligoester acrylate, which is a reactive liquid rubber, as a modifier [trade name: Aronix M-570 (manufactured by Toagosei Chemical Industry Co., Ltd.)].
The total amount of urethane prepolymers in parts A and B is 100
This was used at a ratio of 8 parts to 1 part, and this was used as the third component.

The weight ratio of part A and part B of the urethane prepolymer is 1.
: The first to third components were mixed in a dispenser at a ratio of 1, and the resulting liquid was discharged into a mold to gel with a rise time of 6 minutes and a gel time of 12 minutes. The gelation was completed by heating at ℃ for 30 minutes, and an ink pad having a volume ratio of 0642 was obtained.

Example 3 The following formulations were used as parts A and B of a urethane prepolymer.

Part by weight Part A TDI 382.8 Propylene adipate 750.0 (molecular weight 3'
000) B part polyethylene glycol 993.7 (molecular weight 39
75) Castor oil 95.0 water
26.0 fufu carbon
10.0 silicone oil
0.2bis(2-dimethylamino 0.2
Ethyl) ether 1.0 dibutyltin laurate 0.35 total
2259.05 However, the NCO content in the prepolymer hole is 12.58
The mole is φ.

When these urethane prepolymers A part and B part were mixed in a weight ratio of 1=1 and foamed and cured at room temperature, the resulting porous body had a volume ratio of about 0.04.

On the other hand, the urethane prepolymer part A was used as the first component, and 5 parts of polyvinyl chloride, 1 part of dioctyl phthalate, and KR
- A mixture of 0.2 parts of 1388 is the second precept,
These were mixed in a dispenser such that the weight ratio of Part A and Part B was 1:1, and then the same ink used in Example 1 was added to the mixture in the total amount of urethane prepolymer and modifier. 230 copies out of 100 copies will be the third precept;
A liquid product was obtained by mixing and dispersing.

Next, discharge this liquid into the mold and rise time 5
The volume ratio is 0.3 after foaming and curing with gel time of 8 minutes.
Got an ink roll of 8.

Example 4 A urethane prepolymer having the following formulation was used.

Precepts Weight part Part A D.I. propylene adipate (molecular weight 3000) Part B polyethylene glycol (Molecular weight 3800) water 382.8 1500.0 1850.0 Fluoride carbon dioxide silicone oil Bis(2-dimethylamine ethyl) ether dibutyltin dilaurate Total 32° 20° 0.

1.

, 45 3786.65 However, the NCO content in the bulk of the prepolymer is 7.52 mol.

When these urethane prepolymers A part and B part were mixed in a weight ratio of 1=1 and foamed and cured at room temperature, the resulting porous body had a volume ratio of 0.03.

On the other hand, the urethane prepolymer part A is used as the first component and the particles coated with KR-TTS as a reinforcing agent have a particle size of 0.05 to 0.
Using calcium carbonate in the range of 1μ, this was mixed with 8 parts of urethane prepolymer at a ratio of 4 parts to 100 parts of urethane prepolymer as the second component, and the same ink used in Example 1 was added. 12 parts per 100 parts of the total amount of the urethane prepolymer and the reinforcing agent, respectively.
A ratio of 0 parts was used as the third component.

Note that the calcium carbonate coated with KR-TTS is a surface-untreated calcium carbonate powder 10051 coated with KR-TTS.
It was obtained by mixing with 3 g of S and 3 g of isopropyl alcohol in a ball mill at room temperature for 4 hours, and then evaporating the solvent.

The first to third components were mixed with a dispenser, discharged into a mold, and foamed and hardened with a quiz time of 4 minutes and a gel time of 5 minutes to obtain a liquid with a volume ratio of 0.40.

Each of the ink rolls and ink pads obtained in Examples 1 to 4 had appropriate hardness, and the ink was uniformly contained in the micropores.

Claims (1)

[Claims] 1. A liquid urethane prepolymer of room temperature foaming type. A liquid material in which a modifier for the prepolymer and an ink are mixed and uniformly dispersed is injected into a mold and foamed and cured at room temperature. A method for producing an ink-retaining porous body containing ink in its continuous micropores. 2 The liquid urethane prepolymer has a part A consisting of an isocyanate component and a polyether type and/or polyester type glycol component, and a polyether type and ()
or) part B consisting of a polyester type glycol component, a blowing agent, a catalyst, and a stabilizer. 3. The method according to claim 1, wherein the modifier is at least one selected from the group consisting of thermoplastic elastomers, room temperature crosslinkable solid rubbers, reactive liquid rubbers, and reactive monomers. 4. The method according to claim 3, wherein a coupling agent having a reactive monofunctional group is added to a liquid urethane prepolymer, a thermoplastic elastomer, a room temperature crosslinkable solid rubber, or a liquid rubber. 5. The method according to claim 1, wherein the ink uses an oil or fat as a vehicle and is prepared into a liquid or paste form at room temperature by adding a colorant and a dispersant to the ink. 6. The method according to claim 1, wherein a coupling agent having a reactive monofunctional group is added to the liquid material obtained by mixing a liquid urethane prepolymer, a modifier, and an ink. 3. A method according to claim 2, characterized in that a reinforcing agent is added to part B consisting of a polyether-type and/or polyester-type glycol component, a blowing agent, a catalyst and a stabilizer. 8. The method according to claim 7, wherein the reinforcing agent is an inorganic fine powder or an inorganic single crystal fiber coated with a coupling agent having a reactive monofunctional group. 9. The method according to claim 1, wherein the ink-retaining porous body is an ink roll. 10. The method according to claim 1, wherein the ink retaining porous body is an ink pad.