Silicone Mold Production Process

The choice of mold opening form and the selection of mold line are very important. First, it is convenient for mold taking. Second, the mold line should be selected without affecting the overall effect of the product. Third, it does not affect the product quality. For example, the mold line position of the water series product is too High, when the mold line is required, the product is likely to be cracked; the fourth is to reduce the process operation, such as opening half of the mold.

In order to prevent the flow of the silica gel, the mold is fixed in a regular range with wood or wood. When the mold is opened, the first part of the mold is separated by the wood and the sludge, and there is no gap between the sludge and the mold, and the surface of the sludge is smooth and flat.

After the above work is completed, the plaster or mold is coated with Vaseline or sprayed with a release agent. The smooth product is required to be coated with Vaseline on a clean cotton cloth and evenly applied to the mold for 30 minutes. The species is fully absorbed with Vaseline, and the surface of the mold is wiped clean with a clean cotton cloth, and the surface is required to be bright; while the product with texture is uniformly coated with Vaseline, the silica gel can be adjusted according to the formula. When the silica gel is formulated, it should be stirred in an irregular direction, so that the curing agent and the silica gel are thoroughly mixed to minimize the mixing of air into the rubber. The smooth product is preferably vacuumed when the first layer of glue is applied, and the vacuum degree is required to be maintained at -0.1 Mpa. 7-8 seconds.

After the silica gel is prepared, it should be molded in time. Pour the glue into the highest part of the mold by trickling, let it flow naturally, and use the oil brush to put it in place. If it is a piece of mold silicone, not only the whole product but also the glue should be evenly brushed. Each product is brushed at least three layers of silica gel. The thickness of each layer of silica gel is 1mm. In the process of brushing silica gel, each layer is required to be cured before brushing another layer. When brushing the third layer, add one layer to the second layer. Layer gauze to increase the strength of the silica gel. The entire mold silicone part is controlled to a thickness of 3-4 mm according to the size of the product, and the width is not more than 60 mm of the product width. The silicone gel began to set for 20 minutes.

1. Wash and dry the master mold for smoothing (use a layer of release wax or apply a mold release agent)

2, 500-1000 grams of mold silicone rubber (mold silicone, mold glue, silicone rubber, silicone) as a plastic basin spare;

3. The hardener is weighed according to the weight ratio (generally 1.5-2.5%), then added to the container for mixing, and fully stirred;

4. Add a certain amount of silica thinner depending on the situation (especially the first layer). Until the mixing is uniform, usually 3-5 minutes.

5. After mixing the mold silicone rubber (mold silicone, mold glue, silicone rubber, silica gel) with the hardener, the reaction is carried out at room temperature, and the low molecular alcohol is released. In order to remove the alcohol molecules from the colloid, it is necessary to discharge the bubbles under negative pressure. minute. It can also be done without equipment (mainly depending on the molder's operating experience)

6, multi-layer brushing die, should follow the internal, intermediate and external curing at the same time. When the amount of the curing agent is relatively small, the reaction time is lengthened, the reaction is sufficient, and the colloid is good, so the amount of the curing agent is preferably less in the interior. When the brush is applied, the first layer (the inner layer) is dried and then the second layer is brushed. The operation time is 30-50 minutes, and the demoulding time is 10-15 hours. Curing time is 24 hours. Note that after the first and second layers are applied, it is better to add the mold cloth, which can greatly improve the service life of the mold (but the glass fiber cloth can not be used, otherwise it will easily cause delamination and the whole mold will be scrapped)

7, three-dimensional perfusion mold, generally 10-15 hours of curing as well.

8. After the soft mold is finished, make a plaster or FRP jacket to support the soft silicone mold. Note: 1. Mould line selection: choose the position that does not affect the appearance of the product; choose the position that is easy to process after grouting; select the mold itself is easy to dismantle The position of the mold; select the position where the product is not easily deformed. 2. Do not blindly increase the amount of hardener for the production schedule, otherwise the service life of the silicone mold will be greatly reduced.