1. Amphiphilic core-shell latex particles, said core comprising hydrophobic vinylic grafted copolymer and hydrophobic vinylic polymer, and said shell to which said hydrophobic vinylic polymer is grafted is a hydrophilic, nitrogen-containing polymer.
2. The core-shell latex particles of claim 1, wherein nitrogen of said nitrogen-containing hydrophilic polymer is present as an amino group.
3. The core-shell particles of claim 1 wherein said hydrophilic polymer is selected from natural and synthetic polymers.
4. The core-shell particles of claim 3 wherein said nitrogen-containing polymer is selected from the group consisting of polyethyleneimine and other synthetic amino polymers; chitosan and other N-acetyl sugars; and casein, gelatine, bovine serum albumin and other proteins.
5. The core-shell particles of claim 1 wherein said vinylic polymer is prepared using a vinylic monomer selected from the group consisting of a vinyl monomer, an acrylate monomer and an acrylamide monomer.
6. The core-shell particles of claim 5 wherein said vinylic monomer is of formula R1R2CCH, where R1 is hydrogen or alkyl, and where R2 is alky, aryl, heteroaryl, halo, cyano, or other suitable hydrophobic group.
7. The core-shell particles of claim 5 wherein said vinylic monomer is of formula CH2C(R1)C(R2)CH2 where R1 is hydrogen or halogen or alkyl, and where R2 is hydrogen or alkyl.
8. The core-shell particles of claim 5 wherein said vinylic monomer is of formula CH2CR3COOR4, where R3 is hydrogen or alkyl, and where R4 is alkyl or substituted alkyl, or other suitable hydrophobic group.
9. The core-shell particles of claim 5 wherein said vinylic monomer is of formula CH2CR3COONHR4, where R3 is hydrogen or alkyl, and where R4 is alkyl or substituted alkyl, or other suitable hydrophobic group.
10. The core-shell particles of claim 1, which have a particle size of less than 200 nm, measured as Dn, the number average diameter.
11. The core-shell particles of claim 1, which have a narrow size distribution is narrow, where DnDv is in the range of about 1.1 or 1.2.
12. The core-shell particles of claim 1, which have a polydispersity, MwMn, of the polymerized vinylic monomer in the range 1.5 to 3.
13. A process for the manufacture of particles comprising a core and a shell, said process comprising graft copolymerisation in an aqueous system of a vinylic monomer onto a nitrogen-containing, water-soluble polymer.
14. The process of claim 13, which involves generating radicals on the nitrogen atoms of said hydrophilic polymer, and then initiating free-radical polymerisation of said vinylic monomer, hydrophobic vinylic polymer separating to form latexes of monodisperse core-shell particles with the hydrophobic polymer as the core and said hydrophilic polymer as the shell.
15. The process of claim 14, wherein the weight ratio of monomer to nitrogen-containing polymer is in the range of 1:1 to 10:1.
16. The process of claim 15, wherein said weight ratio is 2:1 to 6:1.
17. The process of claim 14, wherein there is 0.5 to 2 wtwt % nitrogen-containing polymer, and 2 to 10 wtwt % vinylic monomer.
18. The process of claim 14, wherein a radical initiating catalyst is employed.
19. The process of claim 18, wherein the catalyst is a hydroperoxide.
20. The process of claim 18, wherein the amount of vinylic monomer to catalyst is more than 500:1
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A nail gun for driving a nail into a workpiece, comprising:
a body having a lower portion;
a nosepiece through which the nail is ejected, the nosepiece being provided on the lower portion of the body;
a striking mechanism that strikes the nail disposed in the nosepiece;
a switch for activating the striking mechanism;
a trigger member supported pivotably on the body; and
a safety mechanism having a first member, a second member and a third member, the first member being capable of moving downward when the trigger member is pivoted, the second member extending toward the workpiece, and the third member being disposed between the first member and the second member to connect therebetween when the second member is in contact with the workpiece and to disconnect the first member from the second member when the second member is out of contact from the workpiece, and the switch being activated in response to the downward movement of the first member.
2. A nail gun as claimed in claim 1, wherein when the third member connects the first member to the second member, the switch is activated for activating the striking mechanism.
3. A nail gun as claimed in claim 1, wherein when the third member disconnects the first member from the second member, the switch is deactivated.
4. A nail gun for driving a nail into a workpiece, comprising:
a body having a lower portion;
a nosepiece through which the nail is ejected, the nosepiece being provided on the lower portion of the body;
a striking mechanism that strikes the nail disposed in the nosepiece;
a switch for activating the striking mechanism;
a trigger member supported pivotably on the body; and
a safety mechanism having a first member, a second member and a third member, the first member being capable of moving downward when the trigger member is pivoted, the second member extending toward the workpiece, and the third member being disposed between the first member and the second member to connect therebetween;
the safety mechanism including separation mechanism to separate connection between the first member and the second member when the second member is out of contact from the workpiece, and the switch being activated when the first member is connected to the second member.
5. A nail gun as claimed in claim 4, wherein when the separation mechanism separates the connection between the first member and the second member, the switch for the striking mechanism is deactivated.
6. A nail gun for driving a nail into a workpiece, comprising:
a body having a lower portion;
a nosepiece through which the nail is ejected, the nosepiece being provided on the lower portion of the body;
a striking mechanism that strikes the nail disposed in the nosepiece;
a switch for activating the striking mechanism;
a trigger member supported pivotably on the body; and
a safety mechanism having a first member, a second member, a third member, and a shaft disposed between the first member and the second member, the first member being disposed capable of moving downward when the trigger member is pivoted, the second member being disposed in parallel with the first member and extending toward the workpiece, and the third member being pivotably supported on the shaft to convey the movement of the first member to the second member;
wherein when the downward movement of the second member is obstructed, the switch is activated for activating the striking mechanism; and
wherein when downward movement of the second member is unobstructed, the switch is deactivated.
7. A nail gun for driving a nail into a workpiece, comprising:
a body having a lower portion;
a nosepiece through which the nail is ejected, the nosepiece being provided on the lower portion of the body;
a striking mechanism that strikes the nail disposed in the nosepiece;
a switch for activating the striking mechanism;
a trigger member supported pivotably on the body; and
a safety mechanism having a first member, a second member, a third member, and a shaft provided to the first member, the first member being disposed capable of moving downward when the trigger member is pivoted, the second member extending in parallel with the first member toward the workpiece and being formed with a recessed portion, and the third member being pivotably supported on the shaft and having a protrusion engageable with the recessed portion;
wherein when the protrusion is engaged with the recessed portion, the switch is activated for activating the striking mechanism.
8. A nail gun as claimed in claim 7, wherein when the first member is moved downward so that the third member is moved pivotably, the protrusion becomes out of engagement from the recessed portion so that the switch for the striking mechanism is deactivated.