JPH03240529A - Rubber laminate with designed film layer - Google Patents

Abstract

PURPOSE:To make a designed surface with much feelings and senses by interposing a specific composite adhesive layer between a rubber base material and a designed film layer, and mixing staple fibers and natural leather powders into a PVC gelled substance, and in consequence being made into a fabric-like or leather-like designed film layer. CONSTITUTION:A rubber laminate is of the type that designed film layer 3A, 3B are formed with a PVC gelled substance, on a rubber base material 1 made of EPDM and, between the rubber base material and the designed film layer 3A, 3B, an adhesive layer 7 is interposed which consists of blend rubber or the rubber compound thereof being of NBR : 40 - 80wt.%, EPDM : 20 - 60wt.%, and SBR : 0 - 35wt.%, and then the PVC gelled substance is mixed with staple fibers or natural leather powders, and in this fashion, the designed film layers 3A, 3B are made respectively into a fabric-like or leather-like one. In this manner, between the rubber base material and the designed film layer, an excellent adhesiveness can be insured, and a fabric-like or leather-like designed surface can be formed with a good productivity.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a rubber laminate in which a designed coating layer is formed of a PVC gelled product on a rubber substrate made of EPDM.

In addition to the weather strip shown in Figure 3, products to which the rubber laminate with a designed coating layer of the present invention can be applied include:
It can be applied to interior and exterior automotive products such as glass weather strips, side moldings, glass outerwear, and glass innerwear.

A list of polymer/plasticizer abbreviations used in this specification is shown below.

NBR...α,β-unsaturated nitrile-conjugated diene copolymer rubber represented by nitrile rubber, EPDM...
・Represented by ethylene propylene diene ternary rubber,
Ethylene-α-olefin non-conjugated diene copolymer rubber, SBR: Aromatic vinyl compound-conjugated diene copolymer rubber, typified by styrene-butadiene rubber.

pvc...polyvinyl chloride, DOP: Dioctyl phthalate.

<Prior Art> Here, explanation will be given by taking as an example a door fascia strip for an automobile as shown in FIG. 3, but the present invention is not limited to this.

The main bodies of weather strips used in automobiles and the like are usually made of EPDM from the viewpoint of weather resistance, ozone resistance, heat resistance, and the like.

In addition, due to the increasing demand for improved design of automobiles these days, there are cases where it is desired to finish the design surface of the weather strip in a 2♂ cloth tone or leather tone similar to the interior decoration. In such a case, there is a method of attaching cloth or leather to the designed surface (see Japanese Utility Model Publication No. 88655/1988, etc.).

<Problem to be solved by the invention> However, in the above method, the rubber base (Unisa strip)
In order to finish the designed surface of the vulcanized rubber base in a cloth-like manner, for example, many steps are required, such as puff finishing the designed surface of the rubber base after vulcanization, degreasing IA embedding, coating with brimer, applying adhesive, attaching cloth, and curing the adhesive. and productivity was not good.

In view of the above, the present invention provides a rubber laminate with a design (film layer) that can form a cloth-like or leather-like design surface with good productivity on an EPDM rubber substrate. The purpose is to

<Means for Solving the Problems> The design coating film Ffj (=J rubber laminate of the present invention) has the following configuration to solve the above problems.

A rubber laminate in which a design coating layer is formed of a PVC keloid on a rubber substrate made of EPDM, and between the rubber substrate and the design coating layer, NBR: 40 to 80% by weight, EPDM
- A contact agent layer consisting of a blended rubber or a rubber compound thereof having a composition of 20 to 60% by weight and SBR of 0 to 35% by weight is interposed, and the PVC keloid is coated with short fibers or natural It is characterized in that it contains leather powder to form a fabric-like or leather-like design coating layer, respectively.

<Detailed explanation of means> The means of the present invention will be explained in detail below.

In addition, in the following explanation, "%" and "1 part" indicating the compounding unit are as follows.
Units are by weight unless otherwise specified.

1 and 2 show model diagrams of a rubber laminate with a cloth-like or leather-like decorative coating layer according to the present invention.

(1) The rubber base 1 is made of EPDM.

Here, EPDM refers to ethylene, α-olefin (ex
, propylene) is added with a non-conjugated diene such as ethylidene norbornene, dicyclopentadiene, or 1.4 hexadiene as a third component, and copolymerized to introduce a double bond into the side chain, making it sulfur vulcanizable. This is what I did. The polymer is usually blended with auxiliary materials such as reinforcing fillers (carbon black or white carbon), plasticizers, lubricants, and vulcanizing agents. Table 1 shows E that can be used in this example.
The formulation of the PDM rubber compound (solid formulation) is shown.

(2) Then, on the designed surface of the rubber substrate 1, designed coating layers 3A and 3B are formed of a PC gelled product.

Here, PVC paste refers to a particle size of several μm or less (7
) A plastisol or organosol made into a paste by dispersing ff&fine paste resin in a plasticizer or a dispersion medium in which a diluent is added to the plasticizer. ), and when used as a paint, there is no change in weight due to the film forming operation (100% at solid content concentration) compared to solvent-based paints, and the amount of adhesion is large after 2 coats. , there is almost no fire or sanitary danger (see "Plus Deck Processing Technology Handbook", Nikkan Kogyo Shimbun Materials, published December 20, 1978, pp. 485-486). This PVC paste usually contains auxiliary materials such as stabilizers, carbon black, or colorants (pigments, dyes).

(3) One feature of the present invention is that short fibers 4 or natural leather powder 5 are mixed into the PVC gelled product to form fabric-like or leather-like design coating layers 3A and 3B, respectively. shall be.

■For short fibers (pile), materials: nylon, polyester, rayon, etc. Thickness: 05-3. Od, length 0
Use one with a diameter of 5 to 2 mm. The blending amount of short fiber is PV
Add 4 to 100 parts of C paste resin, usually 50 to 1
00 copies.

(2) As the natural leather powder, it is possible to use cowhide, ragweed, horseweed, etc., which are ground into fine powder (1 to 100 um). Specifically, it is commercially available from companies such as Idemitsu Sekiku, etc. under the trade name of Protein Powder.

The blending amount of this natural leather powder is PVC paste resin 1
00 parts, it is usually 20 to 80 parts.

(4) In the present invention, the rubber base 1 and the decorative coating layers 3A and 3B
An adhesive layer (glue line) 7 made of the following Blend rubber or a rubber compound thereof is interposed between the two.

rNBR: 40-80iii%, EPDM: 2o
Bren 1-rubber consisting of ~60% by weight, SBR:O ~35% by weight. The blended rubber is the same as that disclosed in JP-A-62-172043, and is usually prepared by emulsion polymerization.

(2) If the NBR is less than 40%, the adhesion to the decorative coating layer (PVC gel layer) 3A, 3B is poor.

Moreover, if it exceeds 80%, the adhesion to the EPDM rubber substrate 1 will be poor, and the ozone resistance of the adhesive layer itself will also be poor.

■ If the EPDM content is less than 20%, the ozone resistance of the adhesive layer itself is poor, and if the EPDM content exceeds 60%, the decorative coating layer (PV
(c) Gelled layer) Adhesion with 3A and 3B deteriorates.

(2) If the SBR exceeds 35%, the adhesion to the decorative coating layers (PVC keled layers) 3A and 3B will deteriorate, and the ozone resistance of the adhesive layer itself will also deteriorate. Note that SBR is 0
%, or preferably 2% or more because the adhesion to the rubber substrate 1 is improved.

■The above Blen 1 rubber usually contains reinforcing fillers (carbon black or white carbon), plasticizers, lubricants,
Add auxiliary materials such as vulcanizing chemicals and coloring agents if necessary.

However, when the thickness of the adhesive layer is made to be a thin layer of less than 0.5 mm, it is not necessary if migration of auxiliary materials such as a vulcanizing agent from the rubber substrate 1 is expected.

(2) The thickness of the adhesive layer is 0.1 to 2 mm.

If the thickness is less than 0.1 mm, the adhesive layer will not work properly, and if the thickness is less than 2 m.
If it exceeds m, the material cost will increase and the properties of the rubber base will be lost, which is undesirable.

(5) The method of manufacturing a rubber laminate according to the present invention will be explained by taking as an example the case of manufacturing a weather strip as shown in FIG.

(2) Co-extrude the rubber base (unisa strip main body) 1 and adhesive layer 7 using each material. Note that only the adhesive layer 7 may be formed by other coating means such as a knife coating method.

Alternatively, the rubber substrate may be prepared by molding such as injection, transfer, compression, etc., and the adhesive layer may be formed from a common phase, a thin sheet, etc. by means of coating, pressing, etc.

■Subsequently, after heating and vulcanizing the rubber base 1 and adhesive layer 7,
A PVC paste mixed with short fibers or natural leather powder is applied to the designed surface of the rubber substrate 1 and heated to gel to form the designed coating layers 3A and 3B.

The above PVC paste can be applied by any of the general-purpose coating methods such as flow coating, brush coating, roller coating, dipping coating, spray coating, etc., or if the coating surface has an uneven shape. If the surface is easily deformed or deformed, flow painting is recommended.

The coating amount at this time is such that the coating thickness is 50 to 2000 μm depending on the desired design. The thickness of the decorative coating layers 3A and 3B after heating and gelling is 50 to 2000 μm, which is almost the same as the coating thickness before gelling.

In addition, two or more coating devices are prepared, and each coating device is filled with PvC paste with different specifications (for example, a different color, short fibers are mixed in one, and natural leather powder is mixed in the other), and the extrusion direction is By applying it in parallel or in predetermined lengths on the designed surface of the rubber substrate immediately after extrusion, a designed coating layer with a color pattern can be easily formed with good productivity.

This heat kelization process of the PVC paste may be performed after the completion of vulcanization of the rubber base 1 and adhesive layer 7, but from the viewpoint of thermal efficiency and productivity, the process of heating and kelizing the rubber base 1 and adhesive layer 7 It is desirable that the vulcanization conditions for the EPDM rubber and the heat gelling conditions for the PC paste be between the two.

〉. In this case, each step of extruding the rubber laminate, covering the adhesive layer, forming the PVC paste layer, and vulcanizing or heating and gelling them can be performed continuously. That is, after the rubber substrate 1, adhesive layer 7, and decorative coating layers 3A and 3B are continuously extruded or coated, the rubber substrate 1, the adhesive layer 7, and the decorative coating layers 3A and 3B may be continuously extruded or coated, and then transferred to a vulcanization (heat gelling) step.

<Actions and Effects of the Invention> The rubber laminate with a designed coating layer of the present invention has the above-mentioned
A rubber laminate in which a design coating layer made of PVC gel is formed on a rubber base made of DM, and between the rubber base and the design coating layer, 40 to 80% by weight of NBR and EPDM.
An adhesive layer consisting of a blended rubber or a rubber compound thereof having a composition of 20 to 60% by weight and SBR of 0 to 35% by weight is interposed, and short fibers or natural leather powder are interposed in the PVC keloid. Since they are mixed to form a fabric-like or leather-like design coating layer, the following actions and effects are achieved.

Conventionally, in order to finish the designed surface of the rubber base (Unisa strip) in a Japanese style, for example, the designed surface of the rubber base after vulcanization was puff finished, degreased, coated with brimer, coated with adhesive, etc.
It required a lot of man-hours such as attaching the cloth and curing the adhesive. On the other hand, the rubber laminate with a designed coating layer of the present invention does not require such a time-consuming pre-treatment, but can be made by simply interposing an adhesive layer with a specific blended rubber or its rubber compound. Good adhesion can be ensured between the rubber base and the decorative coating layer. Also, there is no need to attach cloth or leather. Therefore, a cloth-like or leather-like design surface can be formed with good productivity on the EPDM rubber substrate.

<Examples/Comparative Examples> Examples conducted to confirm the effects of the present invention will be described below.

Crosshead type extruder (specification cylinder diameter 60mmφ
, compression ratio 1.5), the rubber materials for the rubber substrate shown in Table 1 and for the adhesive layer shown in Table 2 were used to form an adhesive layer (adhesive layer thickness + 0. 4mm
) (width 35mm x thickness 4m)
mt) was extruded (conditions: extrusion speed 5 m/min). Next, the top surface of the extrudate (rubber base) was coated with a PVC paste (after vacuum degassing) mixed with short fibers having the formulation shown in Table 3 to a film thickness of 1 mm using a shower coating method. A design coating layer (PVC paste layer) is formed, and the extrudate is carried into a hot air tank, and the paste layer is heated to gel on the vulcanized mold of the rubber base 1 and adhesive layer under the conditions of 200°C x 1O min. It was done at the same time.

After leaving the example thus prepared at room temperature for 24 hours,
The adhesive strengths between the adhesive layer and the rubber substrate, and between the adhesive layer, the decorative coating layer, and the adhesive layer were measured by a 180° peel test (tensile speed: 10 cm/min).

From the test results shown in Table 4, it was found that the adhesive layer of each example had good adhesion to both the rubber substrate and the decorative coating layer, and when the three-component system containing SBR was used, furthermore, It can be seen that the adhesion of the adhesive layer to the rubber substrate is improved.

Table 4 also shows the rubber physical properties of the adhesive layer measured according to JIS K-1i301. Excessive SBR indicates that the ozone resistance is poor.

In addition, all of the design coating layers had a fabric-like texture with a rich texture.

(unit parts by weight) *Shiraki synthetic rubber■Manufacturing Table 3 *Manufactured by Sumitomo Chemical Co., Ltd. 6

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of a model of a rubber laminate according to the present invention in which the design coating layer has a fabric-like appearance. Figure 2 is a cross-sectional view of a model of a rubber laminate in which the design coating layer has a leather-like appearance. FIG. 1 is a cross-sectional perspective view of a door weather strip that is an example of a fabricated molded product of the present invention. 1...Rubber base, 3A, 3B...Design coating layer, 7...Adhesive layer, D...Design surface. Patent application Toyoda Gosei Co., Ltd.

Claims (1)

[Scope of Claims] A rubber laminate in which a designed coating layer is formed of a gelled product of PVC paste (hereinafter referred to as "PVC gelled product") on a rubber base made of EPDM, wherein the rubber base and the designed Between the coating layer, NBR: 40 to 80% by weight, EPDM: 20
-60% by weight, SBR: 0-35% by weight, an adhesive layer made of a blended rubber or a rubber compound thereof is interposed, and short fibers or natural leather powder are mixed in the PVC gelled product. A rubber laminate with a design coating layer, characterized in that the design coating layer has a fabric-like or leather-like design coating layer.