JPH04183731A - Formed rubber product with high tackiness - Google Patents

Abstract

PURPOSE:To obtain a formed rubber product, preparable into complicated shapes and having high tackiness without any stickiness in processes by impregnating a crosslinked formed product composed of butyl rubber (derivative) with a tackifier and/or a mineral oil-based softener. CONSTITUTION:(A) A formed product obtained by using butyl rubber (derivative) as a main base rubber, blending a crosslinking agent or a filler in somewhat small amounts so as to readily impact tackiness, crosslinking and forming the resultant blend in an amount of 100 pts.wt. is dipped in (B) (B1) a tackifier (e.g. coumarone resin or a rosin derivative) and/or (B2) a mineral oil-based softener (e.g. process oil or paraffin wax) in an amount of 5-200 pts.wt. [the total amount of the components (B1) and (B2)] or a solution of the component (B) and allowed to stand at ambient temperature to 60 deg.C for 12-48hr. The solvent is then removed after completing the dipping when the solvent is used. Thereby, the objective formed rubber product having high tackiness is readily produced.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a highly adhesive rubber molded product that can be used to remove dirt from the soles of shoes and dirt from clothing, and can be used as toys.

(Prior art) There are products that have high adhesion, that is, are sticky, but can be peeled off without tearing, and are used for things such as rugs at the entrance of semiconductor clean rooms because they stick to fine dust and do not let go. Since rubber is easy to impart such properties, molded products are made using this as a base and adding a tackifier (tackifier) to suit the purpose.

These molded products use crosslinked polyurethane elastomer, vinyl chloride, butyl rubber, etc., which easily impart tackiness, as materials, and in all cases, a tackifier is added when the rolls are crossed. In addition, silicone rubber with a low crosslinking density is also used because of its high adhesiveness.

However, all of these have very poor workability because they stick during all the steps of ``crosstalk'', ``removal from the roll'', ``r-molding'', and ``removal from the mold''. Since the strength of the molded product decreases, it is easy to break when removing the molded product from the mold, especially for products with complicated shapes.
I can't create it because it's torn to pieces.

(Problems to be Solved by the Invention) An object of the present invention is to provide a highly adhesive rubber molded product that has no stickiness during the process and can be formed into a complicated shape.

(Means for Solving the Problems) The present invention uses butyl rubber or a butyl rubber derivative as the main base rubber: This is crosslinked and molded by a normal method, and the molded product is treated with a tackifier and/or a mineral oil softener. Impregnate the molding with the tackifier by immersing it in the mold itself or in a solution of the tackifier and/or mineral oil softener in a solvent: If a solvent is used, remove it: by It is a highly adhesive molded product that can be created.

Next, the creation method will be explained in detail.

Butyl rubber or a butyl rubber derivative (for example, halogenated butyl rubber, etc.) is used as the main base rubber, and the composition is designed to easily impart tackiness.

That is, in order to lower the crosslinking density, the amount of crosslinking agent and filler should be small. For example, when sulfur is used as a crosslinking agent, 0 parts of sulfur is added to 100 parts of base rubber.
．． The amount is 2 to 0.5 parts. When baked clay is used as a filler, the amount is 8 to 12 parts based on 100 parts of the base rubber. Typical formulation examples are shown in Table 1.

Table 1 Examples of formulations for highly adhesive rubbers Compounding agent Amount Polycer Bromobutyl X-2' 100 Magnesia
40 sulfur
03 Stearic acid 10
Titanium Oxide'' 1 3.0 Ultramarine
1 1.0□ Baked clay 1 10.0 Knead and mold this. The same molding conditions as usual may be used in each step.

The molded product is immersed in the tackifier or mineral oil softener itself, or in a solution of the tackifier or mineral oil softener dissolved in a solvent. In the present invention, commonly used tackifiers and mineral oil softeners that are compatible with butyl rubber or butyl rubber derivatives are used. Examples of the tackifier include mixtures of Maroturn resin, Kuhn resin, naphthenic process oil, etc., phenol, terpene resin, petroleum hydrocarbon resin, rosin derivatives, and the like. Examples of mineral oil softeners include petroleum softeners, process oils, paraffin wax, and the like. Among these,
One may be used, or two or more may be selected and used in combination.

Low molecular weight tackifiers and mineral oil softeners (molecular weight 6
00 or less), the molded product may be directly immersed. High-molecular weight tackifiers and mineral oil-based softeners can be used in a good solvent (e.g. toluene, trichloroethane, etc.) with approximately 30%
If about 60% is dissolved and the molded product is immersed in this solution,
Tackifiers and mineral oil softeners penetrate molded products more quickly. After the molded article has sufficiently absorbed the solution, the solvent is removed. Since the solvent has a lower boiling point than the tackifier or mineral oil softener, only the solvent can be selectively removed. This method of impregnating with a solvent allows controlling the amount of the tackifier or mineral oil softener impregnated into the molded product. That is, an appropriate amount of the tackifier or mineral oil softener may be dissolved in a solvent, and the molded article may be impregnated with the solution in the maximum amount. After the immersion is completed, only the solvent is removed using an appropriate method, so that the desired amount of tackifier and mineral oil softener remain in the molded product.

The molded product is immersed in a tackifier, a mineral oil softener, or a solution thereof, and left at room temperature to 60°C for 12 to 48 hours. If a solvent is used, after immersion, if the molded product that has absorbed the solution is left in a normal state, only the solvent will evaporate, or the molded product can be placed in a pressure container and heated to 40 to 70°C while the inside of the container is heated. The solvent may be removed by removing pressure. In either case, the amount of tackifier is 5 to 200 parts by weight per 100 parts by weight of the molded product.
It is impregnated in an amount of 10 to 100 parts by weight, preferably 10 to 100 parts by weight.

(Function) Using butyl rubber or its derivatives as a base rubber,
Molded products created using the same molding method as normal ones do not have adhesive properties. When this molded product is immersed in a tackifier, a mineral oil softener, or a solution containing these in a solvent,
The molded product is impregnated with a tackifier, a mineral oil softener, or a solution thereof, and the molded product swells. This is because it has good compatibility with the tackifier, mineral oil softener, or butyl rubber, and the rubber molded product absorbs the tackifier and mineral oil softener and swells considerably. Furthermore, since the compatibility is good, the tackifier and mineral oil softener once absorbed by the molded product will not ooze out from the molded product.

A molded product that absorbs a tackifier or mineral oil softener and swells becomes sticky. However, if a large amount of tackifier or mineral oil-based softener is absorbed, the strength of the molded product will decrease and it will become easier to break, so the amount of tackifier or mineral oil-based softener should be about 100 parts per 100 parts of the molded product. The amount is preferably 10 to 100 parts. In order to control the amount of the tackifier or mineral oil softener, the method of dissolving the tackifier or mineral oil softener in a solvent is used as described above. A molded product that has absorbed a tackifier or a mineral oil softener in this range has high tackiness, but is relatively difficult to tear.

Application examples include rugs that remove dirt from the soles of shoes, and toys because they can be made into complex shapes. In addition, since thin molded products can be made, it can also be used as double-sided tape, and it is possible that it could be used as an adhesive for masking materials when blasting glass.

(Example) Knead according to the formulation example shown in Table 1, and make a 1mm thick, 1c
Create a rectangular molded product measuring m x 5 cm.

The vulcanization conditions were approximately 1706C for 18 minutes. This molded product was impregnated with a tackifier, etc. as in Examples A, B, and C below to create a highly adhesive molded product. Example A) Polybutene (e.g. Nippon Petrochemical 8 stone polybutene HY-100
etc.) Dissolve 30 parts by volume in 70 parts by volume of trichloroethane. The above molded product is immersed in this solution and left at room temperature for 3 days to allow the molded product to absorb the solution. Subsequently, this molded product is placed in a pressure-resistant container, the pressure inside the container is reduced, and the solvent is removed.

Due to the immersion treatment, the volume of the molded product was approximately 1.8 times that before immersion.

Example B) 30 parts of paraffinic process oil to 7 parts of toluene
Dissolve in 0 parts. The molded article described above is immersed in this solution and left at room temperature for 3 days. The molded product that has sufficiently absorbed the solution is placed in a pressure-resistant container, the pressure inside is reduced, and only the solvent is removed.

Due to the immersion treatment, the molded product absorbed paraffinic process oil and approximately doubled in volume.

Example c) Ethylene/α-olefin copolymer oligomer (
30 parts of Mitsui Petrochemical (Lucan) HC-100) is dissolved in 70 parts of trichloroethane, and the molded article described above is immersed in this solution and left at room temperature for 3 days. After sufficient absorption of the solution, the solvent in the molding is removed in the same manner as in Example A.

This example takes advantage of the fact that ethylene/α-olefin copolymer oligomer has good weather resistance. ethylene·
The molded product that has absorbed the α-olefin copolymer oligomer has slightly less tackiness than Example A, but has excellent weather resistance and is less susceptible to deterioration due to light. This example can be applied to items used under direct sunlight or items related to sterile rooms that are irradiated with ultraviolet rays.

(Experiment) Each sample of Example A, Example B, and Example C had absorbed the tackifier and the like and had become large, so they were cut into 1 cm wide pieces. Place each cut sample on a glass plate and press lightly from above. Hook the sample 5 mm from one end onto the hook, and pull the hook vertically. Measure the force required to peel the sample from the glass plate. A sample before immersion treatment was used as a control.

The results are shown in Table 2. The peeling stress was about 5 times that of the control in Examples A and B, and about 4 times that of Example C, indicating that all the samples were imparted with tackiness.

Table 2 Peeling stress measurement results□ (Measurement results for n=5) (Effects) Conventional high-tack molded products add tackifiers from the roll wire rolling stage, so they do not sag during the entire process. Workability was very poor. The highly adhesive molded product of the present invention can be handled in the same way as conventional rubber molded products (i.e., no tackifier is added) without causing any sagging or large deformation. easy. In addition, the manufacturing method is simple because the molded product is simply immersed in the same way as in the past.

Conventional highly adhesive molded products were easily torn apart when removed from the mold, so they were only used for simple-shaped rugs and the like. However, according to the present invention, it can be made into a desired shape, such as a thin double-sided tape or a complicated toy, and the range of use can be expanded.

Claims (1)

[Claims] 1) Rubber molding characterized by using butyl rubber or a butyl rubber derivative as the main base rubber; impregnating the crosslinked molded product with a tackifier and/or a mineral oil softener; thing. 2) The total amount of the tackifier and/or mineral oil softener to be impregnated is 5 parts by weight per 100 parts by weight of the molded product.
The rubber molded product according to claim 1, wherein the amount is 200 parts by weight.