JPS62176406A - Rubber latex puff - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a rubber latex puff, particularly a natural or synthetic rubber latex puff useful for oil cosmetics or contact lens polishing.

(Prior art) Conventionally, puffs for oil-based cosmetics have generally been made from NBR or NR-based synthetic rubber latex sponges or polyurethane foam, but these inherently lack durability and weather resistance. This has the disadvantage that the surface hardens and deteriorates during long-term use, and this deterioration is further accelerated by thermal history such as washing with hot water. There were drawbacks. In addition, when this kind of rubber latex puff or porous foaming agent such as polyurethane foam comes in contact with shallow areas of the skin such as the edges of the eyes or lips, it causes a tingling or stiff feeling, and this is due to its hardening and deterioration. It also had the disadvantage of getting worse as it progressed.

On the other hand, regarding this rubber latex puff, silicone rubber sponge puffs mainly made of organopolysiloxa are also known, and these have excellent heat resistance and weather resistance, and cosmetic puffs using them have a good feel when in contact with the human body. However, compared to the above-mentioned synthetic rubber latex and polyurethane, this has the advantage of being more expensive and less economical.

For this reason, for the above-mentioned natural rubber and synthetic rubber latex puffs, an organopolysiloxane hardened layer is formed on the inner and outer surfaces of the rubber latex puff, and this organopolysiloxane hardened layer adds heat resistance and weather resistance to the latex and gives it a silicone feel. The rubber latex puff obtained in this way is made of organopolysiloxane with excellent mold releasability and has good adhesion to other substances. Due to its poor properties, the organopolysiloxane cured layer peels off from the latex during use, which is a practical inconvenience, so that it has not always been possible to obtain a satisfactory product.

(Structure of the Invention) The present invention relates to a rubber latex puff that solves the above disadvantages, and the inner and outer surfaces of the natural rubber or synthetic rubber latex puff are pretreated with a primer or self-adhesive organopolymer. After being treated with siloxane, a non-self-adhesive cured organopolysiloxane layer is formed on the treated surface.

That is, as a result of various studies on methods for preventing the peeling of the organopolysiloxane cured layer in a rubber latex puff in which an organopolysiloxane cured layer is formed on a rubber latex puff, the present inventor has developed a rubber latex puff made by foam molding of natural rubber or synthetic rubber latex. If the inner and outer surfaces of the puff are treated with a known silicone primer or an organopolysiloxane which itself has self-adhesive properties, and a cured layer of non-self-adhesive organopolysiloxane is formed on this treated surface, this primer-treated layer Alternatively, self-adhesive organopolysiloxane treated layers adhere well to rubber latex, and these treated layers also adhere well to non-self-adhesive organopolysiloxane cured layers; They discovered that the cured siloxane layer does not peel off from the rubber latex, and conducted research on the primer to be used, the type of self-adhesive organopolysiloxane, the processing method, etc., and completed the present invention.

The rubber latex puff as the main material forming the rubber latex puff of the present invention is natural rubber or NBR, NR, SB.
Synthetic rubbers such as R, IR, and CR may be obtained by foaming and molding using a known method, but this material has a relatively fine and uniform cell structure in view of its use as a cosmetic puff. This material is often processed into a curved surface if necessary, and then used for the processing described later.

Primers for treating this rubber latex puff include, for example, 3-glycidoxypropyl-1-rimethoxysilane, 3-mercaptopropyl trime-1-xysilane, and 2-mercaptoethyl l-lymethoxysilane, which are commercially available as carbon functional silane. Ethoxysilane, 2-(
Examples include organosilanes such as 3,4-epoxycyclohexyl)ethyltrimethoxysilane;
Preferably, a composition is prepared by diluting with alcohol or a hydroalcoholic solvent a composition consisting of 25% by weight and 99 to 75% by weight of an alkoxytriazine obtained by etherifying methylol-1-heriazine with a monohydric alcohol having 1 to 4 carbon atoms. However, this also includes other types of silane coupling agents such as vinyltrichlorosilane, vinyltriethoxysilane, vinyltris(β-methoxyethoxy)silane, γ-methacryloxypropylmethoxysilane, N
-β(aminoethyl)γ-aminopropylmethoxysilane, N-β(aminoethyl)γ-aminopropylmethyldime-1-xysilane, γ-chloropropyl1-rimethoxysilane, γ-aminopropyltrimethoxysilane, etc. It may be used alone or as a mixture of two or more of these,
Also, various tetraalkyl titanates, such as tetra-2
- It may be a mixture in which 0.5 to 100 parts by weight of ethylhexyl titanate, tetraphenyl titanate, tetra (β-methoxyethoxy) titanate, tetrabutoxy titanate, etc. are added per 100 parts of heavy electric charge of the above-mentioned silane coupling agent. . The rubber latex puff may be treated with this primer by impregnating the puff with the primer, or by applying it to the surface of the puff by spraying or brushing, and then air-drying it at room temperature for about 30 minutes to remove the solvent.

In addition, the self-adhesive silicone rubber for treating this rubber latex puff is a curable one-component or two-component organopolysiloxane composition containing, for example, a silane coupling agent, tetraalkyl titanate-1, etc. KE66, KE67, KE68, KEI
, 800- KEL, 801 [all Shin-Etsu Chemical ■
This treatment involves adding a vulcanizing agent to the self-adhesive silicone rubber compound, applying it onto the puff, and then curing it at room temperature or by heating with steam. All you have to do is let it sulfurize.

A rubber latex puff treated with this primer or self-adhesive silicone rubber is said to have this treated layer on its inner and outer surfaces; By forming the desired rubber latex puff. A liquid composition is applied to this non-self-adhesive organopolysiloxane cured layer, and this can be either a composition mainly composed of diorganopolysoloxane with a linear structure or a composition mainly composed of organopolysiloxane with a varnish structure. However, it is preferable to use a so-called silicone rubber composition that becomes a silicone rubber elastic body upon curing. This material is made by adding various fillers and catalysts to polysiloxane such as dimethylpolysiloxane, dimethylvinylpolysiloxane, dimethylvinylphenylpolysiloxane, and γ-trifluoropropylmethylvinylpolysiloxane. It may also contain pigments, property-imparting agents such as conductivity-imparting agents, heat-conducting agents, foaming agents, and the like, as well as a fungicide, as required. RTV rubber called vulcanized type (-molded or two-component type) or heat vulcanized rubber commercially available is used. Note that this polysiloxane is one in which an olefin monomer such as an acrylic acid monomer, its ester, or styrene is radically polymerized in its molecular chain;
Furthermore, compositions based on modified organopolysiloxanes, such as those into which polyoxyalkylene groups are introduced as hydrophilic groups, may also be used. However, from the viewpoint of resource saving and pollution problems such as environmental pollution, it is preferable to use the rubber composition without a solvent, and for this reason, it is preferable to form the RTV rubber composition with a low viscosity. Its viscosity is such that it can be applied or impregnated onto a synthetic rubber latex sponge in a solvent-free state, i.e., at 25°C.
is preferably 10,000 centipoise or less. If it is diluted in a solvent, the concentration of the active ingredient is at least 5% by weight or more, preferably 20% by weight or more, and the viscosity at 25°C is 100,000 centiboise or less, preferably 10% by weight or more.
,000 centivoise or less.

A method for impregnating a synthetic rubber latex sponge with a curable organopolysiloxane liquid composition is to immerse the synthetic rubber latex sponge in the liquid composition, fully impregnate it, and then pull it out.

Synthetic rubber latex can be made by squeezing out the excess with a roll, or by sufficiently applying the liquid composition to one or both sides of the sponge using a roll coater, knife coater, etc. (the inside is impregnated by application). A desired amount of organopolysiloxane material is uniformly impregnated on the inner and outer surfaces of the sponge. Thereafter, this is dried and cured at room temperature or under heating to obtain the desired cosmetic puff based on a synthetic rubber latex sponge on which a cured layer of organopolysiloxane is formed.

Note that this puff may be made by treating the entire synthetic rubber latex sponge with a liquid composition of curable organopolysiloxane, but this puff may also be made by treating the entire synthetic rubber latex sponge with a liquid composition of curable organopolysiloxane. Only one side of the sponge may be treated with a liquid composition of curable organopolysiloxane, and the opposite side left untreated, whereby the silicone-treated side has lipophilic properties and A so-called amphoteric cosmetic puff whose treated surface has hydrophilic properties is obtained. Yet again.

A lipophilic organopolysiloxane rubber layer is formed on the inner and outer surfaces of one side of a synthetic rubber latex sponge that has been previously processed into the shape of a makeup puff, and a hydrophilic modified organopolysiloxane rubber is formed on the inner and outer surfaces of the opposite side. It is also possible to form a layered puff, which provides a cosmetic puff that has the excellent texture and weather resistance of silicone on both sides and can be used for both water-based and oil-based products. The lipophilic organopolysiloxane rubber layer uses a composition mainly composed of the above-mentioned ordinary diorganopolysiloxane, and the hydrophilic modified organopolysiloxane rubber layer uses the above-mentioned modified organopolysiloxane into which the polyoxyalkylene group is introduced. It is sufficient to use a composition mainly consisting of.

The puff of the present invention not only has the above-mentioned excellent properties, but also has the advantage that it does not involve any difficulty in processing the curved surface, and can also be made into a water-based or oil-based amphoteric puff.

Although this synthetic rubber latex puff was mainly described above as a cosmetic puff, it is also said to be useful as a contact lens polishing puff, for example, and has improved polishing workability due to the presence of an organopolysiloxane hardened layer. , polish hardening is improved.

Next, examples of the present invention will be given.

Example 1 10 g of 3-glycidoxypropyltrimethoxysilane was added to an NBR latex sponge (specific gravity 0.13) with a thickness of 10 mm, vertical loom, and width 100 I using hexamethoxymethylmelamine Cymel (Cymel, ) 301.
(trade name manufactured by American Thiazid) 50g, immersed in a primer composition prepared by diluting this Log with methanol 90%, air-dried at 25°C for 24 hours, and then applying the wavy cold-curing silicone. Rubber composition/K
E-42TS [Shin-Etsu Chemical Co., Ltd. (trade name: Ili12)] immersed in a 20% toluene solution and air-dried at 25°C for 72 hours to form a cured organopolysiloxane layer on the inner and outer surfaces of the latex sponge, with a specific gravity of 0. A synthetic rubber latex puff of No. 20 was made.

Next, we tested the synthetic rubber latex puff obtained in this way on oil-based cosmetics, and found that it had good ``adhesion'' and texture and feel.

The cured organopolysiloxane film was pleasant to the touch and showed excellent weather resistance, and the cured organopolysiloxane film did not peel off from the surface of the puff, and when it was forcibly removed, the surface of the puff was destroyed.

Example 2 The NBR latex sponge used in Example 1 was replaced with self-adhesive low-temperature curing silicone rubber KEL, 80OLTV.
After immersing it in a 10% toluene solution of (Part name manufactured by Shin-Etsu Chemical Co., Ltd.) and air-drying it at 25℃ for 24 hours, the two-component low-temperature curing silicone rubber KE-106LTV
(Part name manufactured by Shin-Etsu Chemical Co., Ltd.) Immersed in 10% toluene solution, air-dried for 24 hours, heated at 100'C for 1 hour to harden it, and coated the inner and outer surfaces of the latex sponge body with a hardened organopolysiloxane layer. A synthetic rubber latex sponge body having a specific gravity of 0.23 was prepared by forming a synthetic rubber latex sponge body, which was then punched out into a room+φ shape to make a puff.

Next, we conducted a test on the synthetic rubber latex puff obtained in this way for use in oil-based cosmetics, and found that this product had good "adhesion" of cosmetics, and had excellent texture, touch, texture, and weather resistance. When the cured organopolysiloxane layer of this product was peeled off with fingers, it did not peel off from the puff surface, and when it was forcibly peeled off, the puff surface was destroyed.

Comparative Example The NBR rubber latex sponge used in the above-mentioned Examples was used in Example 1 without being subjected to primer treatment or treatment with self-adhesive organopolysiloxane - liquid type room temperature curable silicone rubber composition/KE -4
Immerse in a 20% toluene solution of 2TS (mentioned above) or a 10% toluene solution of two-component low temperature curing silicone rubber KE-106LTV (part name manufactured by Shin-Etsu Chemical Co., Ltd.).
The latex sponge was air-dried for 24 hours at 5° C. to form cured organopolysiloxane layers on the inner and outer surfaces of the latex sponge.

Next, when the organopolysiloxane cured layer was peeled off from the thus obtained sponge body with fingers, it was easily peeled off, so when this product was used as a cosmetic puff, the organopolysiloxane It was confirmed that the cured layer was likely to peel off.

Claims (1)

[Claims] The inner and outer surfaces of a natural rubber or synthetic rubber latex sponge are pretreated with a primer or with a self-adhesive organopolysiloxane, and then a non-self-adhesive organopolysiloxane cured layer is formed on the treated surface. A rubber latex puff characterized by: