JPS6354479A - Adhesive for knife handle and blade - Google Patents

Abstract

PURPOSE:To obtain the title adhesive which can be easily fed to a narrow recessed part of a knife handle and does not damage the appearance of the knife, by using a thermosetting resin which is curable and solid in an uncured state as a component. CONSTITUTION:An adhesive comprises a thermosetting resin which is curable and solid in an uncured state. Examples of the thermosetting resin are epoxy resins, unsaturated polyester resins, phenolic resins, polyurethane resins, etc., among which the epoxy resins are proferred from the viewpoints of excellent boiling resistance and adhesion to metals for a knife. Epoxy resins having a number-average MW of 500-50,000 and an epoxy equivalent of 120-5,000 are preferred. When the epoxy resin is used as the thermosetting resin, a curing agent is used in an amount of 0.7-1.2 equivalents per equivalent of epoxy group.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an adhesive used for joining the handle and blade of a knife.

(Prior Art) Conventionally, knives, especially knives used as Western tableware, have a side channel that joins the handle and the sword. This joining is usually done by welding metals, but the welding technique is difficult and only a particularly skilled person can successfully join them. In other words, it is necessary to provide the blade with adhesive strength without subjecting it to excessive heat history, and to give it a beautiful appearance.

On the other hand, attempts have been made to use liquid thermosetting resins, which are easy to bond with, and have a bonding strength of 14 pairs. However, liquid adhesives have high viscosity at room temperature,
It is sticky, and during processes such as pouring into details,
Work is difficult due to overflowing and adhesion to unnecessary areas,
This has new disadvantages in that it not only spoils the appearance of the knife but also creates a poor working environment.

As a method to improve these problems, it has been proposed to mix a large amount of filler into the liquid adhesive and make it into a putty form to make it easier to work with, but new problems such as decreased adhesive strength and flowability have been proposed. It is occurring in

(Problems to be Solved by the Invention) An object of the present invention is to provide a knife that is solid at room temperature, that allows easy supply of adhesive to the four narrow parts of the handle of the knife, and that does not damage the appearance of the knife. Our goal is to provide adhesive for the handle and sword.

Another object of the present invention is to provide an adhesive for knife handles and blades that is not sticky and provides a significantly improved working environment compared to conventional liquid adhesives.

Another object of the present invention is to provide an adhesive for knife handles and blades that has high adhesive strength, is solid, and therefore easy to measure and supply, and allows for complete automation of the adhesive process.

(Means for Solving the Problems) The present invention relates to a knife handle and blade adhesive made of a curable thermosetting resin that is solid at room temperature in a substantially uncured state.

Examples of curable thermosetting resins that are solid at room temperature and used in the present invention include epoxy resins, unsaturated polyester i resins, phenol resins, noaryl 7-thalerate resins, polyurethane U (fats, polyimide resins), etc. Epoxy resins can be used alone or in combination, and epoxy resins are particularly preferred because they have excellent adhesion to various metals for knives and boiling resistance.

Thermosetting of the present invention? Epoxy-based fj that is suitably used as Jf fat (Jffi has a number average molecular weight of 500
~50.000, and the epoxy equivalent is 120~5,
000 is given as an example. If the number average molecular weight of the epoxy resin is less than 500, the strength in a substantially uncured state will be weak, and if it exceeds <, so, or ooo, the melting temperature of the resin will be in the high temperature range (200° C. or higher), which is not preferable. If the epoxy equivalent is less than 120, the reactivity will be too high and synthesis will be difficult, and the resin will harden before it melts in the bonding process. If it exceeds 120, the crosslinking density of the cured product will be low. Therefore, the heat resistance of the cured product cannot be expected.

As such an epoxy resin, for example, Japanese Patent Application Laid-open No. 60-
92320, which has at least two active hydrogens on nitrogen in one molecule and has a molecular weight of 1000 to 50
000 long-chain amine and an epoxy resin having at least three or more epoxy groups in one molecule, active hydrogen (A)
The equivalent ratio of (B) and epoxy group (B) is (B)/(A) = 3 to 3
Examples include epoxy resins obtained by addition reaction at 0.

Another example is an epoxy resin obtained by reacting a phenolic hydroxyl group-terminated prepolymer with an epoxy having a trifunctional or more functional epoxy group. Examples of the above prepolymers include those obtained by reacting bisphenol A with Epicote 828, ESB-400, etc.; examples of epoxies having trifunctional or higher functional epoxy groups include 0-cresol/borac type epoxy, phenol novolac type epoxy, ELM- 120, E L M
-434 can be listed as 4. Also, screw 7E/-
Examples include high-molecular weight type epoxies and high-molecular weight novolac type epoxies.

Thermosetting resin other than the epoxy resin of the present invention is 0 (as an unsaturated polyester resin used as a resin, for example, 3% styrene is added to isophthalic acid type unsaturated polyester resin).
Examples of phenolic resins include phenol novolac resins mixed with hexamine as a curing agent, and examples of 7lyl 7-talate resins such as noaryl 7. Examples of polyurethane resins include those made by mixing benzoyl peroxide as a curing agent with tallate prepolymer, such as Pylon I'? UX(
For polyimide resins, such as a system in which 1,4-butanol is mixed with an incyanate-terminated prepolymer obtained by extending the aromatic polyol with incyanate (manufactured by Toyobo Co., Ltd.), for example, pyromellitic anhydride and aromatic The polyimide compound is reacted with a polyimide noamine in a room temperature solvent, separated and dried, and when heated, it melts and becomes a cured polyimide product.

The curing agent used in the present invention is not particularly limited as long as it crosslinks the functional groups of the thermosetting resin, but for example, hardening agents for epoxy resins include amines, acid anhydrides, 7-el/- etc. can be used. Specific examples of amines include quethylenetriamine, triethylenetetramine, trimethylhexamethylenediamine, isophoronecyamine, noami7nophenylmethane, noaminodiphenylsulfone, quizylenzamine, meta722diamine, 4,4° -7 tyrene bis(2-chloroaniline) and 7 ducts of these and epoxy υ (fat), etc. Specific examples of l'i2 anhydrides include 7-talic anhydride, tetrahydro-7-talic anhydride, hexahydro-7-talic anhydride, Tetrachlor 7-talic anhydride, methyl nanotullic anhydride, trimellitic anhydride, pyromellitic anhydride, maleic anhydride W
Specific examples of phenols include 7-dinol resins such as 0-cresol novolak and phenol novolak. When an epoxy resin is used as the thermosetting resin, the amount of the curing agent is preferably in the range of 0.7 to 1.2 in terms of equivalent ratio to the epoxy group.

When preparing the adhesive of the present invention, other resins may be used in addition to the thermosetting U(m) as long as they do not impair the purpose of the present invention. For example, phenoxy resin, polyamide #
I resin, polycarbonate) If resin, saturated polyester resin, polyolefin resin, vinyl chloride resin, vinylidene chloride resin, vinyl acetate resin, polyvinyl alcohol resin, and other thermoplastic resins alone, in combination, or in combination with copolymer resins You can also.

In addition, various known additives such as curing accelerators, catalysts (dicyandiamide, tertiary amines, imidazole, Lewis acid amine complexes, etc.), fillers (mica, glass 7 lake, glass powder, glass am, carbon Fibers, inorganic fillers such as silica, talc, and calcium carbonate; organic fillers such as aramid fibers), pigments (benzene, titanium white, etc.), lubricants (zinc stearate, wax, etc.), and other silane couplings. Agents and the like can be added as necessary. It is also possible to add conductivity imparting agents such as gold, silver, copper, aluminum, carbon, conductive calcium carbonate powder, and silver-coated lath beads, glass fibers, carbon fibers, graphite, and the like.

In the present invention, the term "substantially uncured state" means a state in which crosslinking has partially progressed but has not been completed.

Next, the bonding process in the present invention will be explained. In the present invention, the above-mentioned thermosetting resin, curing agent, additives, etc. are mixed, kneaded, cooled, coarsely pulverized, and classified into particle sizes of about 1 to 3. By doing so, it is possible to easily obtain a curable thermosetting resin adhesive that is in a granule-like substantially uncured state and solid at room temperature.

It is also possible to use this granule-like adhesive by further crushing it into powder. Further, a molded article in a substantially uncured state can also be made from the granule-like material by molding means such as injection molding, extrusion molding, transfer molding, compression molding, and casting.

The shape of the molded product can be any arbitrary shape, such as a rod, ring, branched pipe, cup, sheet, film, hollow pipe, pellet, semicircular donut, etc. I can give an example.

The powder, granule, or molded adhesive created in this way is solid at room temperature and retains its shape, but it melts when heated above the melting point of the adhesive. Further, curing and crosslinking reactions proceed, and the bonded object can be bonded in a reinforced manner.

A specific example will be explained below with reference to the drawings.

The IjSI diagram shows a knife for Western tableware used as an embodiment of the present invention, which is obtained by joining a blade 1 and a handle 2 as shown in FIG. In the present invention, as shown in FIG. 3 or 4, the granule-like or powder-like 4I of the present invention is ground 3 or the rod-like molded body 4 is applied to the four parts of the handle 2 of the knife.
When the knife blade 1 is inserted and fitted, and the blade 1 is heated downward to a temperature above the melting point of the adhesive as shown in FIG. The material flows to fill the space at the joint, adhering and hardening.

It is also possible to supply sand, iron powder, or a putty-like substance containing these to the four parts of the knife handle in advance.
This gives the knife a sense of weight.

(Effects of the Invention) The adhesive of the present invention can be used for quantitative management (=volume) of #C adhesive, positioning (=shape) of objects to be adhered, and adaptation to automation such as robots (solid, high strength), making assembly by adhesive very easy. Furthermore, since the main component is a thermosetting resin, it has excellent heat resistance and boiling resistance.

Further, according to the present invention, the adhesive can be easily supplied to the four narrow parts of the handle of the knife, and compared to conventional liquid adhesives, there is no stickiness, and the working environment is significantly improved. In addition, it was also possible to completely eliminate problems such as rash caused by liquid adhesive adhering to the hands.

(Example) Reference examples and examples will be described below. Note that "parts" simply means parts by weight.

Reference Example 1 500 g of Ebiko 828 (bisphenol A type epoxy resin, epoxy equivalent: 189, manufactured by Yuka Shell Epoxy Co., Ltd.) was placed in a reactor, the temperature was raised to 150'C, and 141.7 g of aniline was added to the reactor while stirring. After the addition was completed, the mixture was heated and stirred for an additional 0.5 hours.The temperature was maintained at 150 to 190°C during the 1.5 hours required for the addition reaction, and the completion of the reaction was confirmed by infrared absorption spectrum. (Disappearance of absorption at 910 cm-' by epoxy groups) The amine equivalent of this amine-terminated prepolymer was 2700. This was ground to a size that could pass through a 3 mm mesh.

Reaction 'J'i-1: ESCN-2201111 (cresol novolac type epoxy resin, epoxy equivalent weight 22
0, produced by Sumima Chemical Industry Co., Ltd.], 300g, 180g
Amine-terminated prepolymer 283 heated to °C and ground
．． Add 2g and keep the temperature at 180-190℃, 1.5
The addition reaction was carried out by stirring for a period of time. Completion of the reaction was confirmed when the amine equivalent weight became virtually zero. The epoxy equivalent of the obtained epoxy resin [Epoxy 4J (referred to as fat (A))] was 465.The number average molecular weight was 7500.0 Molecular weight measurement was performed using Waters GPC.

Epoxy resin (A) 50 parts epoxy 43fllTt 1007 (Yuka Shell Epoxy Co., Ltd.*
>50 parts silica powder (325 mesh or less) 50 parts or more 1
After kneading for 40 minutes in a Ni-Goo set at 50°C, 8.2 parts of diaminodiphenylsulfone was added and kneaded for 1 minute.The mixture was rapidly cooled to room temperature using a cooling roll, and then coarsely ground to a size of 31 mm to form granules. A solid adhesive was obtained.

Example 1 The solid adhesive prepared in Reference Example 1 was further ground in a ball mill to obtain a powder with an average particle size of 100 μm. This was designated as adhesive A.

4F1 of adhesive A was supplied to the four parts of the handle 2 of the knife, and the blade 1 of the knife was fitted (FIG. 3). When this was heated in an oven at 180"C for 5 hours with the blade 1 facing downward as shown in Figure 5, the blade 1 and handle 2 were strongly bonded and
Even when dropped from a height onto a concrete floor, blade 1 and handle 2 did not come off.

Example 2 The solid adhesive prepared in Reference Example 1 was heated to a temperature of 125 shillings.
Make a rod-shaped extruded product with a diameter of 31 using an extruder set at ℃ Q50
It was cut to +am length. This was designated as adhesive B.

One bottle of adhesive B was supplied to the four parts of the handle 2 of the knife, and the blade 1 of the knife was fitted (FIG. 4).

After adhesion was carried out in the same manner as in Example 1, sword 1
The blade 1 and the handle 2 were strongly bonded, and the blade 1 and the handle 2 did not come off even when dropped from a height of ll11 onto a concrete floor.

Further, even when the knife bonded using these methods was dropped onto a concrete floor from a height of 11 immediately after being boiled for 50 hours, the sword 1 and handle 2 did not come off.

[Brief explanation of the drawing]

FIG. 1 shows a knife for Western tableware used as an embodiment of the present invention, which is obtained by joining a sword 1 and a handle 2 as shown in FIG. Figures 3 and 4 are schematic diagrams in which the powdered or rod-shaped adhesive of the present invention is inserted into the four parts of the handle of a knife, and the blade of the knife is inserted and fitted. A schematic diagram of the adhesive heated above its melting point is shown. (Above) Patent applicant Toyo Rubber Industries Co., Ltd. Agent Patent attorney 1) Iwao Mura No. 1
Figure 2 Figure 3 Figure 4 Procedural amendment (method) 1. Indication of the case 1985 Patent Order No. 1056 (No. 15 2. Name of the invention Adhesive for knife handle and blade 3. Person making the amendment) Relationship with the Koba matter Patent applicant (:114) Toyo Rubber Industries Co., Ltd. 4, Agent Maru Building, 1-2-8 Shunesaki, Kita-ku, Osaka 530 Tel: 06 (:'165) 0170 '', -1
(8153) Patent Attorney 1) Iwao Mura. 5. Date of amendment order: September 2, 1985 (Shipping date: September 220, 1988)
It is a knife, and...The resulting - is corrected to ``This is a diagram showing a knife, and Figure 2 is a diagram showing it separated into sword 1 and handle 2.''(that's all)

Claims (1)

[Claims] (1) An adhesive for knife handles and blades made of a curable thermosetting resin that is solid at room temperature in a substantially uncured state.